Multilocus sequence data reveal dozens of putative cryptic species in a radiation of endemic Californian mygalomorph spiders (Araneae, Mygalomorphae, Nemesiidae).

PubMed

Leavitt, Dean H; Starrett, James; Westphal, Michael F; Hedin, Marshal

2015-10-01

We use mitochondrial and multi-locus nuclear DNA sequence data to infer both species boundaries and species relationships within California nemesiid spiders. Higher-level phylogenetic data show that the California radiation is monophyletic and distantly related to European members of the genus Brachythele. As such, we consider all California nemesiid taxa to belong to the genus Calisoga Chamberlin, 1937. Rather than find support for one or two taxa as previously hypothesized, genetic data reveal Calisoga to be a species-rich radiation of spiders, including perhaps dozens of species. This conclusion is supported by multiple mitochondrial barcoding analyses, and also independent analyses of nuclear data that reveal general genealogical congruence. We discovered three instances of sympatry, and genetic data indicate reproductive isolation when in sympatry. An examination of female reproductive morphology does not reveal species-specific characters, and observed male morphological differences for a subset of putative species are subtle. Our coalescent species tree analysis of putative species lays the groundwork for future research on the taxonomy and biogeographic history of this remarkable endemic radiation. Copyright © 2015 Elsevier Inc. All rights reserved.

Molecular Predictors of 3D Morphogenesis by Breast Cancer Cell Lines in 3D Culture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Han, Ju; Chang, Hang; Giricz, Orsi

Correlative analysis of molecular markers with phenotypic signatures is the simplest model for hypothesis generation. In this paper, a panel of 24 breast cell lines was grown in 3D culture, their morphology was imaged through phase contrast microscopy, and computational methods were developed to segment and represent each colony at multiple dimensions. Subsequently, subpopulations from these morphological responses were identified through consensus clustering to reveal three clusters of round, grape-like, and stellate phenotypes. In some cases, cell lines with particular pathobiological phenotypes clustered together (e.g., ERBB2 amplified cell lines sharing the same morphometric properties as the grape-like phenotype). Next, associationsmore » with molecular features were realized through (i) differential analysis within each morphological cluster, and (ii) regression analysis across the entire panel of cell lines. In both cases, the dominant genes that are predictive of the morphological signatures were identified. Specifically, PPAR? has been associated with the invasive stellate morphological phenotype, which corresponds to triple-negative pathobiology. PPAR? has been validated through two supporting biological assays.« less

Developmental changes in the skull morphology of common minke whales Balaenoptera acutorostrata.

PubMed

Nakamura, Gen; Kato, Hidehiro

2014-10-01

We investigated growth-related and sex-related morphological changes in the skulls of 144 North Pacific common minke whales Balaenoptera acutorostrata. Measurement was conducted at 39 points on the skull and mandible to extract individual allometric equations relating the length and zygomatic width of the skull. The results revealed no significant differences in skull morphology by sex except for width of occipital bone. The size relative to the skull of the anatomical parts involved in feeding, such as the rostrum and mandible, increased after birth. In contrast, the sensory organs and the anatomical regions involved in neurological function, such as the orbit, tympanic bullae, and foramen magnum, were fully developed at birth, and their relative size reduced over the course of development. This is the first study to investigate developmental changes in the skull morphology using more than 100 baleen whale specimens, and we believe the results of this study will contribute greatly to multiple areas of baleen whale research, including taxonomy and paleontology. © 2014 Wiley Periodicals, Inc.

Evidence for triple-junction rifting focussed on local magmatic centres along Parga Chasma, Venus

NASA Astrophysics Data System (ADS)

Graff, J. R.; Ernst, R. E.; Samson, C.

2018-05-01

Parga Chasma is a discontinuous rift system marking the southern boundary of the Beta-Atla-Themis (BAT) region on Venus. Along a 1500 km section of Parga Chasma, detailed mapping of Magellan Synthetic Aperture Radar images has revealed 5 coronae, 11 local rift zones distinct from a regional extension pattern, and 47 graben-fissure systems with radiating (28), linear (12) and circumferential (7) geometries. The magmatic centres of these graben-fissure systems typically coincide with coronae or large volcanoes, although a few lack any central magmatic or tectonic feature (i.e. are cryptic). Some of the magmatic centres are interpreted as the foci of triple-junction rifting that form the 11 local rift zones. Cross-cutting relationships between graben-fissure systems and local rift faults reveal synchronous formation, implying a genetic association. Additionally, cross-cutting relationships show that local rifting events postdate the regional extension along Parga Chasma, further indicating multiple stages of rifting. Evidence for multiple centres of younger magmatism and local rifting against a background of regional extension provides an explanation for the discontinuous morphology of Parga Chasma. Examination of the Atlantic Rift System (prior to ocean opening) on Earth provides an analogue to the rift morphologies observed on Venus.

The Pleurobemini (Bivalvia: Unionida) revisited: Molecular species delineation using a mitochondrial DNA gene reveals multiple conspecifics and undescribed species

USGS Publications Warehouse

Inoue, Kentaro; Hayes, David M.; Harris, John L.; Johnson, Nathan A.; Morrison, Cheryl L.; Eackles, Michael S.; King, Tim; Jones, Jess W.; Hallerman, Eric M.; Christian, Alan D.; Randklev, Charles R.

2018-01-01

The Pleurobemini (Bivalvia: Unionida) represent approximately one-third of freshwater mussel diversity in North America. Species identification within this group is challenging due to morphological convergence and phenotypic plasticity. Accurate species identification, including characterization of currently unrecognized taxa, is required to develop effective conservation strategies because many species in the group are imperiled. We examined 573 cox1 sequences from 110 currently recognized species (including 13 Fusconaia and 21 Pleurobema species) to understand phylogenetic relationships among pleurobemine species (mainly Fusconaia and Pleurobema) and to delineate species boundaries. The results of phylogenetic analyses showed no geographic structure within widespread species and illustrated a close relationship between Elliptio lanceolata and Parvaspina collina. Constraint tests supported monophyly of the genera Fusconaia and Pleurobema, including the subgenus P. (Sintoxia). Furthermore, results revealed multiple conspecifics, including P. hanleyianum and P. troschelianum, P. chattanoogaense and P. decisum, P. clava and P. oviforme, P. rubrum and P. sintoxia, F. askewi and F. lananensis, and F. cerina and F. flava. Species delimitation analyses identified three currently unrecognized taxa (two in Fusconaia and one in Pleurobema). Further investigation using additional genetic markers and other lines of evidence (e.g., morphology, life history, ecology) are necessary before any taxonomic changes are formalized.

On Dorsal Prothoracic Appendages in Treehoppers (Hemiptera: Membracidae) and the Nature of Morphological Evidence

PubMed Central

Mikó, István; Friedrich, Frank; Yoder, Matthew J.; Hines, Heather M.; Deitz, Lewis L.; Bertone, Matthew A.; Seltmann, Katja C.; Wallace, Matthew S.; Deans, Andrew R.

2012-01-01

A spectacular hypothesis was published recently, which suggested that the “helmet” (a dorsal thoracic sclerite that obscures most of the body) of treehoppers (Insecta: Hemiptera: Membracidae) is connected to the 1st thoracic segment (T1; prothorax) via a jointed articulation and therefore was a true appendage. Furthermore, the “helmet” was interpreted to share multiple characteristics with wings, which in extant pterygote insects are present only on the 2nd (T2) and 3rd (T3) thoracic segments. In this context, the “helmet” could be considered an evolutionary novelty. Although multiple lines of morphological evidence putatively supported the “helmet”-wing homology, the relationship of the “helmet” to other thoracic sclerites and muscles remained unclear. Our observations of exemplar thoraces of 10 hemipteran families reveal multiple misinterpretations relevant to the “helmet”-wing homology hypothesis as originally conceived: 1) the “helmet” actually represents T1 (excluding the fore legs); 2) the “T1 tergum” is actually the anterior dorsal area of T2; 3) the putative articulation between the “helmet” and T1 is actually the articulation between T1 and T2. We conclude that there is no dorsal, articulated appendage on the membracid T1. Although the posterior, flattened, cuticular evagination (PFE) of the membracid T1 does share structural and genetic attributes with wings, the PFE is actually widely distributed across Hemiptera. Hence, the presence of this structure in Membracidae is not an evolutionary novelty for this clade. We discuss this new interpretation of the membracid T1 and the challenges of interpreting and representing morphological data more broadly. We acknowledge that the lack of data standards for morphology is a contributing factor to misinterpreted results and offer an example for how one can reduce ambiguity in morphology by referencing anatomical concepts in published ontologies. PMID:22272287

Ancestral State Reconstruction Reveals Rampant Homoplasy of Diagnostic Morphological Characters in Urticaceae, Conflicting with Current Classification Schemes

PubMed Central

Wu, Zeng-Yuan; Milne, Richard I.; Chen, Chia-Jui; Liu, Jie; Wang, Hong; Li, De-Zhu

2015-01-01

Urticaceae is a family with more than 2000 species, which contains remarkable morphological diversity. It has undergone many taxonomic reorganizations, and is currently the subject of further systematic studies. To gain more resolution in systematic studies and to better understand the general patterns of character evolution in Urticaceae, based on our previous phylogeny including 169 accessions comprising 122 species across 47 Urticaceae genera, we examined 19 diagnostic characters, and analysed these employing both maximum-parsimony and maximum-likelihood approaches. Our results revealed that 16 characters exhibited multiple state changes within the family, with ten exhibiting >eight changes and three exhibiting between 28 and 40. Morphological synapomorphies were identified for many clades, but the diagnostic value of these was often limited due to reversals within the clade and/or homoplasies elsewhere. Recognition of the four clades comprising the family at subfamily level can be supported by a small number carefully chosen defining traits for each. Several non-monophyletic genera appear to be defined only by characters that are plesiomorphic within their clades, and more detailed work would be valuable to find defining traits for monophyletic clades within these. Some character evolution may be attributed to adaptive evolution in Urticaceae due to shifts in habitat or vegetation type. This study demonstrated the value of using phylogeny to trace character evolution, and determine the relative importance of morphological traits for classification. PMID:26529598

Nanoscale morphological and chemical changes of high voltage lithium-manganese rich NMC composite cathodes with cycling.

PubMed

Yang, Feifei; Liu, Yijin; Martha, Surendra K; Wu, Ziyu; Andrews, Joy C; Ice, Gene E; Pianetta, Piero; Nanda, Jagjit

2014-08-13

Understanding the evolution of chemical composition and morphology of battery materials during electrochemical cycling is fundamental to extending battery cycle life and ensuring safety. This is particularly true for the much debated high energy density (high voltage) lithium-manganese rich cathode material of composition Li(1 + x)M(1 - x)O2 (M = Mn, Co, Ni). In this study we combine full-field transmission X-ray microscopy (TXM) with X-ray absorption near edge structure (XANES) to spatially resolve changes in chemical phase, oxidation state, and morphology within a high voltage cathode having nominal composition Li1.2Mn0.525Ni0.175Co0.1O2. Nanoscale microscopy with chemical/elemental sensitivity provides direct quantitative visualization of the cathode, and insights into failure. Single-pixel (∼ 30 nm) TXM XANES revealed changes in Mn chemistry with cycling, possibly to a spinel conformation and likely including some Mn(II), starting at the particle surface and proceeding inward. Morphological analysis of the particles revealed, with high resolution and statistical sampling, that the majority of particles adopted nonspherical shapes after 200 cycles. Multiple-energy tomography showed a more homogeneous association of transition metals in the pristine particle, which segregate significantly with cycling. Depletion of transition metals at the cathode surface occurs after just one cycle, likely driven by electrochemical reactions at the surface.

Nanoscale Morphological and Chemical Changes of High Voltage Lithium–Manganese Rich NMC Composite Cathodes with Cycling

PubMed Central

2015-01-01

Understanding the evolution of chemical composition and morphology of battery materials during electrochemical cycling is fundamental to extending battery cycle life and ensuring safety. This is particularly true for the much debated high energy density (high voltage) lithium–manganese rich cathode material of composition Li1 + xM1 – xO2 (M = Mn, Co, Ni). In this study we combine full-field transmission X-ray microscopy (TXM) with X-ray absorption near edge structure (XANES) to spatially resolve changes in chemical phase, oxidation state, and morphology within a high voltage cathode having nominal composition Li1.2Mn0.525Ni0.175Co0.1O2. Nanoscale microscopy with chemical/elemental sensitivity provides direct quantitative visualization of the cathode, and insights into failure. Single-pixel (∼30 nm) TXM XANES revealed changes in Mn chemistry with cycling, possibly to a spinel conformation and likely including some Mn(II), starting at the particle surface and proceeding inward. Morphological analysis of the particles revealed, with high resolution and statistical sampling, that the majority of particles adopted nonspherical shapes after 200 cycles. Multiple-energy tomography showed a more homogeneous association of transition metals in the pristine particle, which segregate significantly with cycling. Depletion of transition metals at the cathode surface occurs after just one cycle, likely driven by electrochemical reactions at the surface. PMID:25054780

Surface morphology of caldera-forming eruption deposits revealed by lidar mapping of Crater Lake National Park, Oregon- Implications for emplacement and surface modification

USGS Publications Warehouse

Robinson, Joel E.; Bacon, Charles R.; Major, Jon J.; Wright, Heather M.; Vallance, James W.

2017-01-01

Large explosive eruptions of silicic magma can produce widespread pumice fall, extensive ignimbrite sheets, and collapse calderas. The surfaces of voluminous ignimbrites are rarely preserved or documented because most terrestrial examples are heavily vegetated, or severely modified by post-depositional processes. Much research addresses the internal sedimentary characteristics, flow processes, and depositional mechanisms of ignimbrites, however, surface features of ignimbrites are less well documented and understood, except for comparatively small-volume deposits of historical eruptions. The ~7,700 calendar year B.P. climactic eruption of Mount Mazama, USA vented ~50 km3 of magma, deposited first as rhyodacite pumice fall and then as a zoned rhyodacite-to-andesite ignimbrite as Crater Lake caldera collapsed. Lidar collected during summer 2010 reveals the remarkably well-preserved surface of the Mazama ignimbrite and related deposits surrounding Crater Lake caldera in unprecedented detail despite forest cover. The ±1 m lateral and ±4 cm vertical resolution lidar allows surface morphologies to be classified. Surface morphologies are created by internal depositional processes and can point to the processes at work when pyroclastic flows come to rest. We describe nine surface features including furrow-ridge sets and wedge-shaped mounds in pumice fall eroded by high-energy pyroclastic surges, flow- parallel ridges that record the passage of multiple pyroclastic flows, perched benches of marginal deposits stranded by more-mobile pyroclastic-flow cores, hummocks of dense clasts interpreted as lag deposit, transverse ridges that mark the compression and imbrication of flows as they came to rest, scarps indicating ignimbrite remobilization, fields of pit craters caused by phreatic explosions, fractures and cracks caused by extensional processes resulting from ignimbrite volume loss, and stream channels eroded in the newly formed surface. The nine morphologies presented here illustrate a dynamic depositional environment that varied spatially and with time during the eruption, and show that multiple processes modified the ignimbrite after deposition, both during and after the eruption.

Surface morphology of caldera-forming eruption deposits revealed by lidar mapping of Crater Lake National Park, Oregon - Implications for deposition and surface modification

NASA Astrophysics Data System (ADS)

Robinson, Joel E.; Bacon, Charles R.; Major, Jon J.; Wright, Heather M.; Vallance, James W.

2017-08-01

Large explosive eruptions of silicic magma can produce widespread pumice fall, extensive ignimbrite sheets, and collapse calderas. The surfaces of voluminous ignimbrites are rarely preserved or documented because most terrestrial examples are heavily vegetated, or severely modified by post-depositional processes. Much research addresses the internal sedimentary characteristics, flow processes, and depositional mechanisms of ignimbrites, however, surface features of ignimbrites are less well documented and understood, except for comparatively small-volume deposits of historical eruptions. The 7700 calendar year B.P. climactic eruption of Mount Manama, USA, vented 50 km3 of magma, deposited first as rhyodacite pumice fall and then as a zoned rhyodacite-to-andesite ignimbrite as Crater Lake caldera collapsed. Lidar collected during summer 2010 reveals the remarkably well-preserved surface of the Manama ignimbrite and related deposits surrounding Crater Lake caldera in unprecedented detail despite forest cover. The ± 1 m lateral and ± 4 cm vertical resolution lidar allows surface morphologies to be classified. Surface morphologies are created by internal depositional processes and can point to the processes at work when pyroclastic flows come to rest. We describe nine surface features including furrow-ridge sets and wedge-shaped mounds in pumice fall eroded by high-energy pyroclastic surges, flow-parallel ridges that record the passage of multiple pyroclastic flows, perched benches of marginal deposits stranded by more-mobile pyroclastic-flow cores, hummocks of dense clasts interpreted as lag deposit, transverse ridges that mark the compression and imbrication of flows as they came to rest, scarps indicating ignimbrite remobilization, fields of closely spaced pits caused by phreatic explosions, fractures and cracks due to extensional processes resulting from ignimbrite volume loss, and stream channels eroded in the newly formed surface. The nine morphologies presented here illustrate a dynamic depositional environment that varied spatially and with time during the eruption, and show that multiple processes modified the ignimbrite after deposition, both during and after the eruption.

Biogeography, phylogeny, and morphological evolution of central Texas cave and spring salamanders

PubMed Central

2013-01-01

Background Subterranean faunal radiations can result in complex patterns of morphological divergence involving both convergent or parallel phenotypic evolution and cryptic species diversity. Salamanders of the genus Eurycea in central Texas provide a particularly challenging example with respect to phylogeny reconstruction, biogeography and taxonomy. These predominantly aquatic species inhabit karst limestone aquifers and spring outflows, and exhibit a wide range of morphological and genetic variation. We extensively sampled spring and cave populations of six Eurycea species within this group (eastern Blepsimolge clade), to reconstruct their phylogenetic and biogeographic history using mtDNA and examine patterns and origins of cave- and surface-associated morphological variation. Results Genetic divergence is generally low, and many populations share ancestral haplotypes and/or show evidence of introgression. This pattern likely indicates a recent radiation coupled with a complex history of intermittent connections within the aquatic karst system. Cave populations that exhibit the most extreme troglobitic morphologies show no or very low divergence from surface populations and are geographically interspersed among them, suggesting multiple instances of rapid, parallel phenotypic evolution. Morphological variation is diffuse among cave populations; this is in contrast to surface populations, which form a tight cluster in morphospace. Unexpectedly, our analyses reveal two distinct and previously unrecognized morphological groups encompassing multiple species that are not correlated with spring or cave habitat, phylogeny or geography, and may be due to developmental plasticity. Conclusions The evolutionary history of this group of spring- and cave-dwelling salamanders reflects patterns of intermittent isolation and gene flow influenced by complex hydrogeologic dynamics that are characteristic of karst regions. Shallow genetic divergences among several species, evidence of genetic exchange, and nested relationships across morphologically disparate cave and spring forms suggests that cave invasion was recent and many troglobitic morphologies arose independently. These patterns are consistent with an adaptive-shift hypothesis of divergence, which has been proposed to explain diversification in other karst fauna. While cave and surface forms often do not appear to be genetically isolated, morphological diversity within and among populations may be maintained by developmental plasticity, selection, or a combination thereof. PMID:24044519

Spatially Directed Proteomics of the Human Lens Outer Cortex Reveals an Intermediate Filament Switch Associated With the Remodeling Zone

PubMed Central

Wenke, Jamie L.; McDonald, W. Hayes; Schey, Kevin L.

2016-01-01

Purpose To quantify protein changes in the morphologically distinct remodeling zone (RZ) and adjacent regions of the human lens outer cortex using spatially directed quantitative proteomics. Methods Lightly fixed human lens sections were deparaffinized and membranes labeled with fluorescent wheat germ agglutinin (WGA-TRITC). Morphology directed laser capture microdissection (LCM) was used to isolate tissue from four distinct regions of human lens outer cortex: differentiating zone (DF), RZ, transition zone (TZ), and inner cortex (IC). Liquid chromatography-tandem mass spectrometry (LC-MS/MS) of the plasma membrane fraction from three lenses (21-, 22-, and 27-year) revealed changes in major cytoskeletal proteins including vimentin, filensin, and phakinin. Peptides from proteins of interest were quantified using multiple reaction monitoring (MRM) mass spectrometry and isotopically-labeled internal peptide standards. Results Results revealed an intermediate filament switch from vimentin to beaded filament proteins filensin and phakinin that occurred at the RZ. Several other cytoskeletal proteins showed significant changes between regions, while most crystallins remained unchanged. Targeted proteomics provided accurate, absolute quantification of these proteins and confirmed vimentin, periplakin, and periaxin decrease from the DF to the IC, while filensin, phakinin, and brain acid soluble protein 1 (BASP1) increase significantly at the RZ. Conclusions Mass spectrometry-compatible fixation and morphology directed laser capture enabled proteomic analysis of narrow regions in the human lens outer cortex. Results reveal dramatic cytoskeletal protein changes associated with the RZ, suggesting that one role of these proteins is in membrane deformation and/or the establishment of ball and socket joints in the human RZ. PMID:27537260

A Quantile Regression Approach to Understanding the Relations Between Morphological Awareness, Vocabulary, and Reading Comprehension in Adult Basic Education Students

PubMed Central

Tighe, Elizabeth L.; Schatschneider, Christopher

2015-01-01

The purpose of this study was to investigate the joint and unique contributions of morphological awareness and vocabulary knowledge at five reading comprehension levels in Adult Basic Education (ABE) students. We introduce the statistical technique of multiple quantile regression, which enabled us to assess the predictive utility of morphological awareness and vocabulary knowledge at multiple points (quantiles) along the continuous distribution of reading comprehension. To demonstrate the efficacy of our multiple quantile regression analysis, we compared and contrasted our results with a traditional multiple regression analytic approach. Our results indicated that morphological awareness and vocabulary knowledge accounted for a large portion of the variance (82-95%) in reading comprehension skills across all quantiles. Morphological awareness exhibited the greatest unique predictive ability at lower levels of reading comprehension whereas vocabulary knowledge exhibited the greatest unique predictive ability at higher levels of reading comprehension. These results indicate the utility of using multiple quantile regression to assess trajectories of component skills across multiple levels of reading comprehension. The implications of our findings for ABE programs are discussed. PMID:25351773

The Interior Olivary Complex of Guinea Pig: Cytoarchitecture and Cellular Morphology

DTIC Science & Technology

1986-01-01

The oscillatory phenomenon ap- dye -coupling [471 between 1.0. cells might have been pre- peared in a sampling of neurons from all of the...information derived from injections of the ing of multiple cells from the Lucifer yellow injection into fluorescent dye Lucifer yellow revealed that...aggregates of only one 1.0. neuron [41. The early Golgi analyses also rv- inferior olive neurons are dye -coupled, presumably through vealed at least two

An integrative framework to reevaluate the Neotropical catfish genus Guyanancistrus (Siluriformes: Loricariidae) with particular emphasis on the Guyanancistrus brevispinis complex.

PubMed

Fisch-Muller, Sonia; Mol, Jan H A; Covain, Raphaël

2018-01-01

Characterizing and naming species becomes more and more challenging due to the increasing difficulty of accurately delineating specific bounderies. In this context, integrative taxonomy aims to delimit taxonomic units by leveraging the complementarity of multiple data sources (geography, morphology, genetics, etc.). However, while the theoretical framework of integrative taxonomy has been explicitly stated, methods for the simultaneous analysis of multiple data sets are poorly developed and in many cases different information sources are still explored successively. Multi-table methods developed in the field of community ecology provide such an intregrative framework. In particular, multiple co-inertia analysis is flexible enough to allow the integration of morphological, distributional, and genetic data in the same analysis. We have applied this powerfull approach to delimit species boundaries in a group of poorly differentiated catfishes belonging to the genus Guyanancistrus from the Guianas region of northeastern South America. Because the species G. brevispinis has been claimed to be a species complex consisting of five species, particular attention was paid to taxon. Separate analyses indicated the presence of eight distinct species of Guyanancistrus, including five new species and one new genus. However, none of the preliminary analyses revealed different lineages within G. brevispinis, and the multi-table analysis revealed three intraspecific lineages. After taxonomic clarifications and description of the new genus, species and subspecies, a reappraisal of the biogeography of Guyanancistrus members was performed. This analysis revealed three distinct dispersals from the Upper reaches of Amazonian tributaries toward coastal rivers of the Eastern Guianas Ecoregion. The central role played by the Maroni River, as gateway from the Amazon basin, was confirmed. The Maroni River was also found to be a center of speciation for Guyanancistrus (with three species and two subspecies), as well as a source of dispersal of G. brevispinis toward the other main basins of the Eastern Guianas.

An integrative framework to reevaluate the Neotropical catfish genus Guyanancistrus (Siluriformes: Loricariidae) with particular emphasis on the Guyanancistrus brevispinis complex

PubMed Central

Fisch-Muller, Sonia; Mol, Jan H. A.

2018-01-01

Characterizing and naming species becomes more and more challenging due to the increasing difficulty of accurately delineating specific bounderies. In this context, integrative taxonomy aims to delimit taxonomic units by leveraging the complementarity of multiple data sources (geography, morphology, genetics, etc.). However, while the theoretical framework of integrative taxonomy has been explicitly stated, methods for the simultaneous analysis of multiple data sets are poorly developed and in many cases different information sources are still explored successively. Multi-table methods developed in the field of community ecology provide such an intregrative framework. In particular, multiple co-inertia analysis is flexible enough to allow the integration of morphological, distributional, and genetic data in the same analysis. We have applied this powerfull approach to delimit species boundaries in a group of poorly differentiated catfishes belonging to the genus Guyanancistrus from the Guianas region of northeastern South America. Because the species G. brevispinis has been claimed to be a species complex consisting of five species, particular attention was paid to taxon. Separate analyses indicated the presence of eight distinct species of Guyanancistrus, including five new species and one new genus. However, none of the preliminary analyses revealed different lineages within G. brevispinis, and the multi-table analysis revealed three intraspecific lineages. After taxonomic clarifications and description of the new genus, species and subspecies, a reappraisal of the biogeography of Guyanancistrus members was performed. This analysis revealed three distinct dispersals from the Upper reaches of Amazonian tributaries toward coastal rivers of the Eastern Guianas Ecoregion. The central role played by the Maroni River, as gateway from the Amazon basin, was confirmed. The Maroni River was also found to be a center of speciation for Guyanancistrus (with three species and two subspecies), as well as a source of dispersal of G. brevispinis toward the other main basins of the Eastern Guianas. PMID:29298344

Predicting age from cortical structure across the lifespan.

PubMed

Madan, Christopher R; Kensinger, Elizabeth A

2018-03-01

Despite interindividual differences in cortical structure, cross-sectional and longitudinal studies have demonstrated a large degree of population-level consistency in age-related differences in brain morphology. This study assessed how accurately an individual's age could be predicted by estimates of cortical morphology, comparing a variety of structural measures, including thickness, gyrification and fractal dimensionality. Structural measures were calculated across up to seven different parcellation approaches, ranging from one region to 1000 regions. The age prediction framework was trained using morphological measures obtained from T1-weighted MRI volumes collected from multiple sites, yielding a training dataset of 1056 healthy adults, aged 18-97. Age predictions were calculated using a machine-learning approach that incorporated nonlinear differences over the lifespan. In two independent, held-out test samples, age predictions had a median error of 6-7 years. Age predictions were best when using a combination of cortical metrics, both thickness and fractal dimensionality. Overall, the results reveal that age-related differences in brain structure are systematic enough to enable reliable age prediction based on metrics of cortical morphology. © 2018 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

HIGH-REDSHIFT DUST OBSCURED GALAXIES: A MORPHOLOGY-SPECTRAL ENERGY DISTRIBUTION CONNECTION REVEALED BY KECK ADAPTIVE OPTICS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Melbourne, J.; Matthews, K.; Soifer, B. T.

A simple optical to mid-IR color selection, R - [24]>14, i.e., f {sub {nu}}(24 {mu}m)/f {sub {nu}}(R) {approx}> 1000, identifies highly dust obscured galaxies (DOGs) with typical redshifts of z {approx} 2 {+-} 0.5. Extreme mid-IR luminosities (L {sub IR} > 10{sup 12-14}) suggest that DOGs are powered by a combination of active galactic nuclei (AGNs) and star formation, possibly driven by mergers. In an effort to compare their photometric properties with their rest-frame optical morphologies, we obtained high-spatial resolution (0.''05-0.''1) Keck Adaptive Optics K'-band images of 15 DOGs. The images reveal a wide range of morphologies, including small exponentialmore » disks (eight of 15), small ellipticals (four of 15), and unresolved sources (two of 15). One particularly diffuse source could not be classified because of low signal-to-noise ratio. We find a statistically significant correlation between galaxy concentration and mid-IR luminosity, with the most luminous DOGs exhibiting higher concentration and smaller physical size. DOGs with high concentration also tend to have spectral energy distributions (SEDs) suggestive of AGN activity. Thus, central AGN light may be biasing the morphologies of the more luminous DOGs to higher concentration. Conversely, more diffuse DOGs tend to show an SED shape suggestive of star formation. Two of 15 in the sample show multiple resolved components with separations of {approx}1 kpc, circumstantial evidence for ongoing mergers.« less

Morphology, development, and evolution of fetal membranes and placentation in squamate reptiles.

PubMed

Blackburn, Daniel G; Flemming, Alexander F

2009-09-15

Current studies on fetal membranes of reptiles are providing insight into three major historical transformations: evolution of the amniote egg, evolution of viviparity, and evolution of placentotrophy. Squamates (lizards and snakes) are ideal for such studies because their fetal membranes sustain embryos in oviparous species and contribute to placentas in viviparous species. Ultrastructure of the fetal membranes in oviparous corn snakes (Pituophis guttatus) shows that the chorioallantois is specialized for gas exchange and the omphalopleure, for water absorption. Transmission and scanning electron microscopic studies of viviparous thamnophine snakes (Thamnophis, Storeria) have revealed morphological specializations for gas exchange and absorption in the intra-uterine environment that represent modifications of features found in oviparous species. Thus, fetal membranes in oviparous species show morphological differentiation for distinct functions that have been recruited and enhanced under viviparous conditions. The ultimate in specialization of fetal membranes is found in viviparous skinks of South America (Mabuya) and Africa (Trachylepis, Eumecia), in which placentotrophy accounts for nearly all of the nutrients for development. Ongoing research on these lizards has revealed morphological specializations of the chorioallantoic placenta through which nutrient transfer is accomplished. In addition, African Trachylepis show an invasive form of implantation, in which uterine epithelium is replaced by invading chorionic cells. Ongoing analysis of these lizards shows how integration of multiple lines of evidence can provide insight into the evolution of developmental and reproductive specializations once thought to be confined to eutherian mammals.

A Quantile Regression Approach to Understanding the Relations Among Morphological Awareness, Vocabulary, and Reading Comprehension in Adult Basic Education Students.

PubMed

Tighe, Elizabeth L; Schatschneider, Christopher

2016-07-01

The purpose of this study was to investigate the joint and unique contributions of morphological awareness and vocabulary knowledge at five reading comprehension levels in adult basic education (ABE) students. We introduce the statistical technique of multiple quantile regression, which enabled us to assess the predictive utility of morphological awareness and vocabulary knowledge at multiple points (quantiles) along the continuous distribution of reading comprehension. To demonstrate the efficacy of our multiple quantile regression analysis, we compared and contrasted our results with a traditional multiple regression analytic approach. Our results indicated that morphological awareness and vocabulary knowledge accounted for a large portion of the variance (82%-95%) in reading comprehension skills across all quantiles. Morphological awareness exhibited the greatest unique predictive ability at lower levels of reading comprehension whereas vocabulary knowledge exhibited the greatest unique predictive ability at higher levels of reading comprehension. These results indicate the utility of using multiple quantile regression to assess trajectories of component skills across multiple levels of reading comprehension. The implications of our findings for ABE programs are discussed. © Hammill Institute on Disabilities 2014.

Variations in the morphology of Rhizomucor pusillus in granulomatous lesions of a Magellanic penguin (Spheniscus magellanicus).

PubMed

Suzuta, Fumiko; Kimura, Kumiko; Urakawa, Ryo; Kusuda, Yukio; Tanaka, Shogo; Hanafusa, Yasuko; Haritani, Makoto

2015-08-01

This report presents a new case of mucormycosis encountered in penguin characterized by morphological variation of hyphae and presence of sporangia with numerous sporangiospores. A 4.5-year-old Magellanic penguin (Spheniscus magellanicus) died after exhibiting anorexia, poor nutritional condition and dyspnea. Multiple nodular lesions were observed in the thoracic and abdominal regions. Histopathologically, hyphae of various sizes were seen in the lungs, air sac and nodular lesions. Myriad sporangiospores and several sporangia were observed in/around the bronchi or parabronchi. The very narrow and short hyphae in the nodules were not consistent with the characteristics of Mucorales. However, for most hyphae, including those in the nodules, sporangiospores and sporangia, immunohistochemistry revealed Mucorales-positive reactions. In addition, these fungi were identified as Rhizomucor pusillus by gene analysis.

Morphology evolution in strain-compensated multiple quantum well structures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ledentsov, N. N., E-mail: nikolay.ledentsov@v-i-systems.com; Shchukin, V. A.; Rouvimov, S.

2014-01-20

Morphology evolution in (In,Ga)As-Ga(As,P) strain-compensated multilayer structures is studied. The effects of nanoscale interface corrugation and phase separation are evident after the third period of the multilayer structure and become more pronounced with each new stack until the sixth period. Then, the interface stabilizes pointing to the formation of strain-balanced equilibrium interface structure. The epitaxial structure remains defect-free up to the maximum number (twenty) of periods studied. In a structure with a high lattice mismatch between the neighboring layers, In{sub 0.40}Ga{sub 0.60}As/GaAs{sub 0.85}P{sub 0.15}, clusters of dislocations are revealed already in the third period. The observed phenomena are critical formore » proper engineering of optoelectronic devices.« less

Change in Tongue Morphology in Response to Expiratory Resistance Loading Investigated by Magnetic Resonance Imaging

PubMed Central

Yanagisawa, Yukio; Matsuo, Yoshimi; Shuntoh, Hisato; Mitamura, Masaaki; Horiuchi, Noriaki

2013-01-01

[Purpose] The purpose of this study was to investigate the effect of expiratory resistance load on the tongue area encompassing the suprahyoid and genioglossus muscles. [Subjects] The subjects were 30 healthy individuals (15 males, 15 females, mean age: 28.9 years). [Methods] Magnetic resonance imaging was used to investigate morphological changes in response to resistive expiratory pressure loading in the area encompassing the suprahyoid and genioglossus muscles. Images were taken when water pressure was sustained at 0%, 10%, 30%, and 50% of maximum resistive expiratory pressure. We then measured tongue area using image analysis software, and the morphological changes were analyzed using repeated measures analysis of variance followed by post hoc comparisons. [Results] A significant change in the tongue area was detected in both sexes upon loading. Multiple comparison analysis revealed further significant differences in tongue area as well as changes in tongue area in response to the different expiratory pressures. [Conclusion] The findings demonstrate that higher expiratory pressure facilitates greater reduction in tongue area. PMID:24259824

Multiple regression analysis of anthropometric measurements influencing the cephalic index of male Japanese university students.

PubMed

Hossain, Md Golam; Saw, Aik; Alam, Rashidul; Ohtsuki, Fumio; Kamarul, Tunku

2013-09-01

Cephalic index (CI), the ratio of head breadth to head length, is widely used to categorise human populations. The aim of this study was to access the impact of anthropometric measurements on the CI of male Japanese university students. This study included 1,215 male university students from Tokyo and Kyoto, selected using convenient sampling. Multiple regression analysis was used to determine the effect of anthropometric measurements on CI. The variance inflation factor (VIF) showed no evidence of a multicollinearity problem among independent variables. The coefficients of the regression line demonstrated a significant positive relationship between CI and minimum frontal breadth (p < 0.01), bizygomatic breadth (p < 0.01) and head height (p < 0.05), and a negative relationship between CI and morphological facial height (p < 0.01) and head circumference (p < 0.01). Moreover, the coefficient and odds ratio of logistic regression analysis showed a greater likelihood for minimum frontal breadth (p < 0.01) and bizygomatic breadth (p < 0.01) to predict round-headedness, and morphological facial height (p < 0.05) and head circumference (p < 0.01) to predict long-headedness. Stepwise regression analysis revealed bizygomatic breadth, head circumference, minimum frontal breadth, head height and morphological facial height to be the best predictor craniofacial measurements with respect to CI. The results suggest that most of the variables considered in this study appear to influence the CI of adult male Japanese students.

Non-monophyly and intricate morphological evolution within the avian family Cettiidae revealed by multilocus analysis of a taxonomically densely sampled dataset

PubMed Central

2011-01-01

Background The avian family Cettiidae, including the genera Cettia, Urosphena, Tesia, Abroscopus and Tickellia and Orthotomus cucullatus, has recently been proposed based on analysis of a small number of loci and species. The close relationship of most of these taxa was unexpected, and called for a comprehensive study based on multiple loci and dense taxon sampling. In the present study, we infer the relationships of all except one of the species in this family using one mitochondrial and three nuclear loci. We use traditional gene tree methods (Bayesian inference, maximum likelihood bootstrapping, parsimony bootstrapping), as well as a recently developed Bayesian species tree approach (*BEAST) that accounts for lineage sorting processes that might produce discordance between gene trees. We also analyse mitochondrial DNA for a larger sample, comprising multiple individuals and a large number of subspecies of polytypic species. Results There are many topological incongruences among the single-locus trees, although none of these is strongly supported. The multi-locus tree inferred using concatenated sequences and the species tree agree well with each other, and are overall well resolved and well supported by the data. The main discrepancy between these trees concerns the most basal split. Both methods infer the genus Cettia to be highly non-monophyletic, as it is scattered across the entire family tree. Deep intraspecific divergences are revealed, and one or two species and one subspecies are inferred to be non-monophyletic (differences between methods). Conclusions The molecular phylogeny presented here is strongly inconsistent with the traditional, morphology-based classification. The remarkably high degree of non-monophyly in the genus Cettia is likely to be one of the most extraordinary examples of misconceived relationships in an avian genus. The phylogeny suggests instances of parallel evolution, as well as highly unequal rates of morphological divergence in different lineages. This complex morphological evolution apparently misled earlier taxonomists. These results underscore the well-known but still often neglected problem of basing classifications on overall morphological similarity. Based on the molecular data, a revised taxonomy is proposed. Although the traditional and species tree methods inferred much the same tree in the present study, the assumption by species tree methods that all species are monophyletic is a limitation in these methods, as some currently recognized species might have more complex histories. PMID:22142197

Molecular Testing in Multiple Synchronous Lung Adenocarcinomas: Case Report and Literature Review.

PubMed

Rafael, Oana C; Lazzaro, Richard; Hasanovic, Adnan

2016-02-01

Discovery of driver mutations in pulmonary adenocarcinoma has revolutionized the field of thoracic oncology with major impact on therapy and diagnosis. Testing for EGFR, ALK, and KRAS mutations has become part of everyday practice. We report a case with multiple synchronous primary pulmonary adenocarcinomas in a 72-year-old female with previous history of smoking. The patient presented with cough and bilateral lung ground glass opacities. A positron emission tomography/computed tomography scan showed no activity in mediastinal lymph nodes. She underwent a left upper lobe biopsy and a right upper lobe wedge resection. Pathology revealed 4 morphologically distinct adenocarcinoma foci, suggestive of synchronous primary lung tumors. Molecular testing demonstrated no mutation in the left tumor. Three different driver mutations were present in the right lung tumors: KRAS codon 12 G12D and G12V and EGFR exon 21 L858R mutation, confirming the initial histologic impression. Subsequently, left upper lobe lobectomy showed 3 additional foci of adenocarcinoma with different morphologies, suggestive of synchronous primaries as well. No additional molecular testing was performed. Synchronous pulmonary adenocarcinomas are not uncommon; however, 4 or more synchronous tumors are rare. Distinguishing multiple primary tumors from intrapulmonary metastases is a common problem in thoracic oncology with major implications for staging, prognosis, and treatment. Lung adenocarcinoma subclassification based on predominant and coexisting histologic patterns can greatly facilitate differentiation between intrapulmonary metastases and multiple synchronous tumors. Use of molecular profiling is recommended since it further increases confidence in the diagnostic workup of multiple pulmonary adenocarcinomas and helps guiding therapy. © The Author(s) 2015.

The Impact of Morphological Awareness on Word Reading and Dictation in Chinese Early Adolescent Readers With and Without Dyslexia.

PubMed

Kalindi, Sylvia Chanda; Chung, Kevin Kien Hoa

2018-01-01

This study investigated the role of morphological awareness in understanding Chinese word reading and dictation among Chinese-speaking adolescent readers in Hong Kong as well as the cognitive-linguistic profile of early adolescent readers with dyslexia. Fifty-four readers with dyslexia in Grades 5 and 6 were compared with 54 chronological age-matched (CA) typical readers on the following measures of cognitive-linguistic and literacy skills: morphological awareness, phonological awareness, visual-orthographic knowledge, rapid naming, vocabulary knowledge, verbal short-term memory (STM), Chinese word reading, and dictation (or spelling). The results indicated that early adolescent readers with dyslexia performed less well than the typical readers on all cognitive-linguistic and literacy measures except the phonological measures. Both groups' scores showed substantial correlations between morphological awareness and Chinese word reading and dictation. Visual-orthographic knowledge and rapid naming were also associated with dictation in early adolescent readers with and without dyslexia, respectively. Moderated multiple regression analyses further revealed that morphological awareness and rapid naming explained unique variance in word reading and dictation for the readers with dyslexia and typical readers separately after controlling readers' age and group effect. These results highlight the potential importance of morphological awareness and rapid naming in Chinese word reading and writing in Chinese early adolescents' literacy development and impairment.

The Pleurobemini (Bivalvia: Unionida) revisited: Molecular species delineation using a mitochondrial DNA gene reveals multiple conspecifics and undescribed species

USGS Publications Warehouse

Inoue, Kentaro; Hayes, David M.; Harris, John L.; Johnson, Nathan A.; Morrison, Cheryl L.; Eackles, Michael S.; King, Tim; Jones, Jess W.; Hallerman, Eric M.; Christian, Alan D.; Randklev, Charles R.

2018-01-01

The Pleurobemini (Bivalvia: Unionida) represent approximately one-third of freshwater mussel diversity in North America. Species identification within this group is challenging due to morphological convergence and phenotypic plasticity. Accurate species identification, including characterisation of currently unrecognised taxa, is required to develop effective conservation strategies because many species in the group are imperiled. We examined 575 cox1 sequences from 110 currently recognised species (including 13 Fusconaia and 21 Pleurobema species) to understand phylogenetic relationships among pleurobemine species (mainly Fusconaia and Pleurobema) and to delineate species boundaries. The results of phylogenetic analyses showed no geographic structure within widespread species and illustrated a close relationship between Elliptio lanceolata and Parvaspina collina. Constraint tests supported monophyly of the genera Fusconaia and Pleurobema, including the subgenus P. (Sintoxia). Furthermore, results revealed multiple conspecifics, including P. hanleyianum and P. troschelianum, P. chattanoogaense and P. decisum, P. clava and P. oviforme, P. rubrum and P. sintoxia, F. askewi and F. lananensis, and F. cerina and F. flava. Species delimitation analyses identified three currently unrecognised taxa (two in Fusconaia and one in Pleurobema). Further investigation using additional genetic markers and other lines of evidence (e.g. morphology, life history, ecology) are necessary before any taxonomic changes are formalised.

Isolation and characterization of T7-like lytic bacteriophages infecting multidrug resistant Pseudomonas aeruginosa isolated from Egypt.

PubMed

El Didamony, Gamal; Askora, Ahmed; Shehata, Aya A

2015-06-01

In this study, two lytic phages designated as ϕPSZ1 and ϕPSZ2 infecting multidrug resistant Pseudomonas aeruginosa were isolated from sewage samples collected in Zagazig, Egypt. Morphological analysis by transmission electron microscopy revealed that both phages belong to the podoviridae family and resembles typical T7-like phages. ϕPSZ1 has a head of about 60 ± 5 nm in diameter with a short tail of 19 ± 2 nm in length, while ϕPSZ2 has a head of about 57 ± 5 nm in diameter with a short tail of 14 ± 2 nm in length. Both phages were shown to be able to infect 13 different P. aeruginosa strains and has no effect on other tested bacteria. In spite of morphological similarity, these phages showed diverged genomic sequences revealed by restriction enzyme digestion analysis. One-step growth curves of bacteriophages revealed eclipse and latent periods of 12 min for ϕPSZ1 and 15 min for ϕPSZ2, respectively, with burst sizes of about 100 per infected cell. Phage treatment prevented the growth of P. aeruginosa for up to 18 h with multiplicity of infection ratios of 1. These results suggest that both phages have a high potential for phage application to control P. aeruginosa.

Resolving Recent Plant Radiations: Power and Robustness of Genotyping-by-Sequencing.

PubMed

Fernández-Mazuecos, Mario; Mellers, Greg; Vigalondo, Beatriz; Sáez, Llorenç; Vargas, Pablo; Glover, Beverley J

2018-03-01

Disentangling species boundaries and phylogenetic relationships within recent evolutionary radiations is a challenge due to the poor morphological differentiation and low genetic divergence between species, frequently accompanied by phenotypic convergence, interspecific gene flow and incomplete lineage sorting. Here we employed a genotyping-by-sequencing (GBS) approach, in combination with morphometric analyses, to investigate a small western Mediterranean clade in the flowering plant genus Linaria that radiated in the Quaternary. After confirming the morphological and genetic distinctness of eight species, we evaluated the relative performances of concatenation and coalescent methods to resolve phylogenetic relationships. Specifically, we focused on assessing the robustness of both approaches to variations in the parameter used to estimate sequence homology (clustering threshold). Concatenation analyses suffered from strong systematic bias, as revealed by the high statistical support for multiple alternative topologies depending on clustering threshold values. By contrast, topologies produced by two coalescent-based methods (NJ$_{\\mathrm{st}}$, SVDquartets) were robust to variations in the clustering threshold. Reticulate evolution may partly explain incongruences between NJ$_{\\mathrm{st}}$, SVDquartets and concatenated trees. Integration of morphometric and coalescent-based phylogenetic results revealed (i) extensive morphological divergence associated with recent splits between geographically close or sympatric sister species and (ii) morphological convergence in geographically disjunct species. These patterns are particularly true for floral traits related to pollinator specialization, including nectar spur length, tube width and corolla color, suggesting pollinator-driven diversification. Given its relatively simple and inexpensive implementation, GBS is a promising technique for the phylogenetic and systematic study of recent radiations, but care must be taken to evaluate the robustness of results to variation of data assembly parameters.

Prevalence of cryptic species in morphologically uniform taxa - fast speciation and evolutionary radiation in Asian toads.

PubMed

Liu, Zuyao; Chen, Guoling; Zhu, Tianqi; Zeng, Zhaochi; Lyu, Zhitong; Wang, Jian; Messenger, Kevin; Greenberg, Anthony J; Guo, Zixiao; Yang, Ziheng; Shi, Suhua; Wang, Yingyong

2018-06-16

Diversity and distributions of cryptic species have long been a vexing issue. Identification of species boundaries is made difficult by the lack of obvious morphological differences. Here, we investigate the cryptic diversity and evolutionary history of an underappreciated group of Asian frog species (Megophrys) to explore the pattern and dynamic of amphibian cryptic species. We sequenced four mitochondrial genes and five nuclear genes and delineated species using multiple approaches, combining DNA and mating-call data. A Bayesian species tree was generated to estimate divergence times and to reconstruct ancestral ranges. Macroevolutionary analyses and hybridization tests were conducted to explore the evolutionary dynamics of this cryptic group. Our phylogenies support the current subgenera. We revealed 43 cryptic species, 158% higher than previously thought. The species-delimitation results were further confirmed by mating-call data and morphological divergence. We found that these Asian frogss entered China from the Sunda Shelf 48 Mya, followed by an ancient radiation event during middle Miocene. We confirmed the efficiency of the multispecies coalescent model for delimitation of species with low morphological diversity. Species diversity of Megophrys is severely underappreciated, and species distributions have been misestimated as a result. Copyright © 2018. Published by Elsevier Inc.

Combining morphometrics with molecular taxonomy: how different are similar foliose keratose sponges from the Australian tropics?

PubMed

Abdul Wahab, M A; Fromont, J; Whalan, S; Webster, N; Andreakis, N

2014-04-01

Sponge taxonomy can be challenging as many groups exhibit extreme morphological plasticity induced by local environmental conditions. Foliose keratose sponges of the sub-family Phyllospongiinae (Dictyoceratida, Thorectidae: Strepsichordaia, Phyllospongia and Carteriospongia) are commonly found in intertidal and subtidal habitats of the Indo-Pacific. Lacking spicules, these sponges can be difficult to differentiate due to the lack of reliable morphological characters for species delineation. We use molecular phylogenies inferred from the nuclear Internal Transcribed Spacer 2 region (ITS2) and morphometrics (19 characters; 52 character states) to identify evolutionarily significant units (ESUs; sensu Moritz) within foliose Phyllosponginiids collected from seven geographic locations across tropical eastern and Western Australia. The ITS2 topology was congruent with the tree derived from Bayesian inference of discrete morphological characters supporting expected taxonomic relationships at the genus level and the identification of five ESUs. However, phylogenies inferred from the ITS2 marker revealed multiple sequence clusters, some of which were characterised by distinct morphological features and specific geographic ranges. Our results are discussed in light of taxonomic incongruences within this study, hidden sponge diversity and the role of vicariant events in influencing present day distribution patterns. Copyright © 2014 Elsevier Inc. All rights reserved.

Morphology Instruction in the Science Classroom for Students Who Are Deaf: A Multiple Probe Across Content Analysis.

PubMed

Trussell, Jessica W; Nordhaus, Jason; Brusehaber, Alison; Amari, Brittany

2018-04-17

Deaf and hard-of-hearing (DHH) students have exhibited a morphological knowledge delay that begins in preschool and persists through college. Morphological knowledge is critical to vocabulary understanding and text comprehension in the science classroom. We investigated the effects of morphological instruction, commonly referred to as Word Detectives, on the morphological knowledge of college-age DHH students in a science course. We implemented a multiple probe across behaviors single-case experimental design study with nine student participants. The student participants attended the National Technical Institute for the Deaf. A functional relation was found between the morphological instruction and the student participants' improvement of morphological knowledge regarding the morphemes taught during instruction. These findings indicate that DHH students benefit from morphological instruction to build their vocabulary knowledge in content-area classrooms, such as science courses.

Shaping sound in space: the regulation of inner ear patterning.

PubMed

Groves, Andrew K; Fekete, Donna M

2012-01-01

The inner ear is one of the most morphologically elaborate tissues in vertebrates, containing a group of mechanosensitive sensory organs that mediate hearing and balance. These organs are arranged precisely in space and contain intricately patterned sensory epithelia. Here, we review recent studies of inner ear development and patterning which reveal that multiple stages of ear development - ranging from its early induction from the embryonic ectoderm to the establishment of the three cardinal axes and the fine-grained arrangement of sensory cells - are orchestrated by gradients of signaling molecules.

Shaping sound in space: the regulation of inner ear patterning

PubMed Central

Groves, Andrew K.; Fekete, Donna M.

2012-01-01

The inner ear is one of the most morphologically elaborate tissues in vertebrates, containing a group of mechanosensitive sensory organs that mediate hearing and balance. These organs are arranged precisely in space and contain intricately patterned sensory epithelia. Here, we review recent studies of inner ear development and patterning which reveal that multiple stages of ear development – ranging from its early induction from the embryonic ectoderm to the establishment of the three cardinal axes and the fine-grained arrangement of sensory cells – are orchestrated by gradients of signaling molecules. PMID:22186725

Three-dimensional multifunctional optical coherence tomography for skin imaging

NASA Astrophysics Data System (ADS)

Li, En; Makita, Shuichi; Hong, Young-Joo; Kasaragod, Deepa; Sasaoka, Tomoko; Yamanari, Masahiro; Sugiyama, Satoshi; Yasuno, Yoshiaki

2016-02-01

Optical coherence tomography (OCT) visualizes cross-sectional microstructures of biological tissues. Recent developments of multifunctional OCT (MF-OCT) provides multiple optical contrasts which can reveal currently unknown tissue properties. In this contribution we demonstrate multifunctional OCT specially designed for dermatological investigation. And by utilizing it to measure four different body parts of in vivo human skin, three-dimensional scattering OCT, OCT angiography, polarization uniformity tomography, and local birefringence tomography images were obtained by a single scan. They respectively contrast the structure and morphology, vasculature, melanin content and collagen traits of the tissue.

Parallel genetic origins of pelvic reduction in vertebrates

PubMed Central

Shapiro, Michael D.; Bell, Michael A.; Kingsley, David M.

2006-01-01

Despite longstanding interest in parallel evolution, little is known about the genes that control similar traits in different lineages of vertebrates. Pelvic reduction in stickleback fish (family Gasterosteidae) provides a striking example of parallel evolution in a genetically tractable system. Previous studies suggest that cis-acting regulatory changes at the Pitx1 locus control pelvic reduction in a population of threespine sticklebacks (Gasterosteus aculeatus). In this study, progeny from intergeneric crosses between pelvic-reduced threespine and ninespine (Pungitius pungitius) sticklebacks also showed severe pelvic reduction, implicating a similar genetic origin for this trait in both genera. Comparative sequencing studies in complete and pelvic-reduced Pungitius revealed no differences in the Pitx1 coding sequences, but Pitx1 expression was absent from the prospective pelvic region of larvae from pelvic-reduced parents. A much more phylogenetically distant example of pelvic reduction, loss of hindlimbs in manatees, shows a similar left–right size bias that is a morphological signature of Pitx1-mediated pelvic reduction in both sticklebacks and mice. These multiple lines of evidence suggest that changes in Pitx1 may represent a key mechanism of morphological evolution in multiple populations, species, and genera of sticklebacks, as well as in distantly related vertebrate lineages. PMID:16945911

Hemodynamic and morphological characteristics of unruptured posterior communicating artery aneurysms with oculomotor nerve palsy.

PubMed

Lv, Nan; Yu, Ying; Xu, Jinyu; Karmonik, Christof; Liu, Jianmin; Huang, Qinghai

2016-08-01

OBJECT Unruptured posterior communicating artery (PCoA) aneurysms with oculomotor nerve palsy (ONP) have a very high risk of rupture. This study investigated the hemodynamic and morphological characteristics of intracranial aneurysms with high rupture risk by analyzing PCoA aneurysms with ONP. METHODS Fourteen unruptured PCoA aneurysms with ONP, 33 ruptured PCoA aneurysms, and 21 asymptomatic unruptured PCoA aneurysms were included in this study. The clinical, morphological, and hemodynamic characteristics were compared among the different groups. RESULTS The clinical characteristics did not differ among the 3 groups (p > 0.05), whereas the morphological and hemodynamic analyses showed that size, aspect ratio, size ratio, undulation index, nonsphericity index, ellipticity index, normalized wall shear stress (WSS), and percentage of low WSS area differed significantly (p < 0.05) among the 3 groups. Furthermore, multiple comparisons revealed that these parameters differed significantly between the ONP group and the asymptomatic unruptured group and between the ruptured group and the asymptomatic unruptured group, except for size, which differed significantly only between the ONP group and the asymptomatic unruptured group (p = 0.0005). No morphological or hemodynamic parameters differed between the ONP group and the ruptured group. CONCLUSIONS Unruptured PCoA aneurysms with ONP demonstrated a distinctive morphological-hemodynamic pattern that was significantly different compared with asymptomatic unruptured PCoA aneurysms and was similar to ruptured PCoA aneurysms. The larger size, more irregular shape, and lower WSS might be related to the high rupture risk of PCoA aneurysms.

Sperm Associated Antigen 6 (SPAG6) Regulates Fibroblast Cell Growth, Morphology, Migration and Ciliogenesis

PubMed Central

Li, Wei; Mukherjee, Abir; Wu, Jinhua; Zhang, Ling; Teves, Maria E.; Li, Hongfei; Nambiar, Shanti; Henderson, Scott C.; Horwitz, Alan R.; Strauss III, Jerome F.; Fang, Xianjun; Zhang, Zhibing

2015-01-01

Mammalian Spag6 is the orthologue of Chlamydomonas PF16, which encodes a protein localized in the axoneme central apparatus, and regulates flagella/cilia motility. Most Spag6-deficient mice are smaller in size than their littermates. Because SPAG6 decorates microtubules, we hypothesized that SPAG6 has other roles related to microtubule function besides regulating flagellar/cilia motility. Mouse embryonic fibroblasts (MEFs) were isolated from Spag6-deficient and wild-type embryos for these studies. Both primary and immortalized Spag6-deficient MEFs proliferated at a much slower rate than the wild-type MEFs, and they had a larger surface area. Re-expression of SPAG6 in the Spag6-deficient MEFs rescued the abnormal cell morphology. Spag6-deficient MEFs were less motile than wild-type MEFs, as shown by both chemotactic analysis and wound-healing assays. Spag6-deficient MEFs also showed reduced adhesion associated with a non-polarized F-actin distribution. Multiple centrosomes were observed in the Spag6-deficient MEF cultures. The percentage of cells with primary cilia was significantly reduced compared to the wild-type MEFs, and some Spag6-deficient MEFs developed multiple cilia. Furthermore, SPAG6 selectively increased expression of acetylated tubulin, a microtubule stability marker. The Spag6-deficient MEFs were more sensitive to paclitaxel, a microtubule stabilizer. Our studies reveal new roles for SPAG6 in modulation of cell morphology, proliferation, migration, and ciliogenesis. PMID:26585507

Innervation of taste buds revealed with Brainbow-labeling in mouse.

PubMed

Zaidi, Faisal N; Cicchini, Vanessa; Kaufman, Daniel; Ko, Elizabeth; Ko, Abraham; Van Tassel, Heather; Whitehead, Mark C

2016-12-01

Nerve fibers that surround and innervate the taste bud were visualized with inherent fluorescence using Brainbow transgenic mice that were generated by mating the founder line L with nestin-cre mice. Multicolor fluorescence revealed perigemmal fibers as branched within the non-taste epithelium and ending in clusters of multiple rounded swellings surrounding the taste pore. Brainbow-labeling also revealed the morphology and branching pattern of single intragemmal fibers. These taste bud fibers frequently innervated both the peripheral bud, where immature gemmal cells are located, and the central bud, where mature, differentiated cells are located. The fibers typically bore preterminal and terminal swellings, growth cones with filopodia, swellings, and rounded retraction bulbs. These results establish an anatomical substrate for taste nerve fibers to contact and remodel among receptor cells at all stages of their differentiation, an interpretation that was supported by staining with GAP-43, a marker for growing fibers and growth cones. © 2016 Anatomical Society.

Three-dimensional multispectral optoacoustic mesoscopy reveals melanin and blood oxygenation in human skin in vivo.

PubMed

Schwarz, Mathias; Buehler, Andreas; Aguirre, Juan; Ntziachristos, Vasilis

2016-01-01

Optical imaging plays a major role in disease detection in dermatology. However, current optical methods are limited by lack of three-dimensional detection of pathophysiological parameters within skin. It was recently shown that single-wavelength optoacoustic (photoacoustic) mesoscopy resolves skin morphology, i.e. melanin and blood vessels within epidermis and dermis. In this work we employed illumination at multiple wavelengths for enabling three-dimensional multispectral optoacoustic mesoscopy (MSOM) of natural chromophores in human skin in vivo operating at 15-125 MHz. We employ a per-pulse tunable laser to inherently co-register spectral datasets, and reveal previously undisclosed insights of melanin, and blood oxygenation in human skin. We further reveal broadband absorption spectra of specific skin compartments. We discuss the potential of MSOM for label-free visualization of physiological biomarkers in skin in vivo. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Impact craters on Venus - Initial analysis from Magellan

NASA Technical Reports Server (NTRS)

Phillips, Roger J.; Arvidson, Raymond E.; Boyce, Joseph M.; Campbell, Donald B.; Guest, John E.

1991-01-01

The general features of impact craters are described emphasizing two aspects: the effect of the atmosphere on crater and ejecta morphology and the implications of the distribution and appearance of the craters for the volcanic and tectonic resurfacing history of Venus. Magellan radar images reveal 135 craters about 15 km in diameter containing central peaks, multiple central peaks, and peak rings. Craters smaller than 15 km exhibit multiple floors or appear in clusters. Surface flows of material initially entrained in the atmosphere are characterized. Zones of low radar albedo originated from deformation of the surface by the shock or pressure wave associated with the incoming meteoroid surround many craters. A spectrum of surface ages on Venus ranging from 0 to 800 million years indicates that Venus must be a geologically active planet.

Investigating lithium-ion battery materials during overcharge-induced thermal runaway: an operando and multi-scale X-ray CT study.

PubMed

Finegan, Donal P; Scheel, Mario; Robinson, James B; Tjaden, Bernhard; Di Michiel, Marco; Hinds, Gareth; Brett, Dan J L; Shearing, Paul R

2016-11-16

Catastrophic failure of lithium-ion batteries occurs across multiple length scales and over very short time periods. A combination of high-speed operando tomography, thermal imaging and electrochemical measurements is used to probe the degradation mechanisms leading up to overcharge-induced thermal runaway of a LiCoO 2 pouch cell, through its interrelated dynamic structural, thermal and electrical responses. Failure mechanisms across multiple length scales are explored using a post-mortem multi-scale tomography approach, revealing significant morphological and phase changes in the LiCoO 2 electrode microstructure and location dependent degradation. This combined operando and multi-scale X-ray computed tomography (CT) technique is demonstrated as a comprehensive approach to understanding battery degradation and failure.

[Clinical value of MRI united-sequences examination in diagnosis and differentiation of morphological sub-type of hilar and extrahepatic big bile duct cholangiocarcinoma].

PubMed

Yin, Long-Lin; Song, Bin; Guan, Ying; Li, Ying-Chun; Chen, Guang-Wen; Zhao, Li-Ming; Lai, Li

2014-09-01

To investigate MRI features and associated histological and pathological changes of hilar and extrahepatic big bile duct cholangiocarcinoma with different morphological sub-types, and its value in differentiating between nodular cholangiocarcinoma (NCC) and intraductal growing cholangiocarcinoma (IDCC). Imaging data of 152 patients with pathologically confirmed hilar and extrahepatic big bile duct cholangiocarcinoma were reviewed, which included 86 periductal infiltrating cholangiocarcinoma (PDCC), 55 NCC, and 11 IDCC. Imaging features of the three morphological sub-types were compared. Each of the subtypes demonstrated its unique imaging features. Significant differences (P < 0.05) were found between NCC and IDCC in tumor shape, dynamic enhanced pattern, enhancement degree during equilibrium phase, multiplicity or singleness of tumor, changes in wall and lumen of bile duct at the tumor-bearing segment, dilatation of tumor upstream or downstream bile duct, and invasion of adjacent organs. Imaging features reveal tumor growth patterns of hilar and extrahepatic big bile duct cholangiocarcinoma. MRI united-sequences examination can accurately describe those imaging features for differentiation diagnosis.

Global Gene Expression Analysis in PKCα-/- Mouse Skin Reveals Structural Changes in the Dermis and Defective Wound Granulation Tissue.

PubMed

Cooper, Nichola H; Balachandra, Jeya P; Hardman, Matthew J

2015-12-01

The skin's mechanical integrity is maintained by an organized and robust dermal extracellular matrix (ECM). Resistance to mechanical disruption hinges primarily on homeostasis of the dermal collagen fibril architecture, which is regulated, at least in part, by members of the small leucine-rich proteoglycan (SLRP) family. Here we present data linking protein kinase C alpha (PKCα) to the regulated expression of multiple ECM components including SLRPs. Global microarray profiling reveals deficiencies in ECM gene expression in PKCα-/- skin correlating with abnormal collagen fibril morphology, disorganized dermal architecture, and reduced skin strength. Detailed analysis of the skin and wounds from wild-type and PKCα-/- mice reveals a failure to upregulate collagen and other ECM components in response to injury, resulting in delayed granulation tissue deposition in PKCα-/- wounds. Thus, our data reveal a previously unappreciated role for PKCα in the regulation of ECM structure and deposition during skin wound healing.

Molecular and morphological data of the freshwater fish Glandulocauda melanopleura (Characiformes: Characidae) provide evidences of river captures and local differentiation in the Brazilian Atlantic Forest

PubMed Central

Menezes, Naércio Aquino; Costa-Silva, Guilherme José; Oliveira, Claudio

2018-01-01

The current distribution of freshwater fishes across multiple basins along Eastern Brazil can be associated to two main events: river captures or temporary paleoconnections. Apparently, river captures had a more significant role on distribution and structuring of species from upland areas, such as Glandulocauda melanopleura. Populations of this species are found in contiguous drainages in presently isolated upper parts of Rio Tietê and the coastal basins of Guaratuba, Itatinga, Itanháem, and Ribeira de Iguape, in the Atlantic Forest domain. The allopatric and disjoint distribution of G. melanopleura associated with variation of morphological characters detected among geographically isolated populations stimulated this study. Thus, an integrative approach was undertaken, including morphological and molecular data, to better understand the evolutionary history of the species and the area where it occurs. Molecular analyses based on two mitochondrial markers revealed a strong genetic structure within G. melanopleura, that allowed recognition of two lineages, one distributed in both the upper Tietê and Itanhaém and the other in the Guaratuba. Overall, morphological data revealed some intraspecific overlapping variation, indicating that all samples are conspecific. Phylogenetic and phylogeographic analyses allied to divergence times and geomorphological information indicate that the current distribution of G. melanopleura is a result of relatively recent river captures involving the Tietê and some other coastal drainages. Although of recent origin, they occurred long enough to completely isolate these populations, since there are no haplotypes sharing between them. The conservation status of this species is also discussed, and our results corroborate the need to understand population structure for conservation planning. PMID:29579069

Whole mount nuclear fluorescent imaging: convenient documentation of embryo morphology

PubMed Central

Sandell, Lisa L.; Kurosaka, Hiroshi; Trainor, Paul A.

2012-01-01

Here we describe a relatively inexpensive and easy method to produce high quality images that reveal fine topological details of vertebrate embryonic structures. The method relies on nuclear staining of whole mount embryos in combination with confocal microscopy or conventional widefield fluorescent microscopy. In cases where confocal microscopy is used in combination with whole mount nuclear staining, the resulting embryo images can rival the clarity and resolution of images of similar specimens produced by Scanning Electron Microscopy (SEM). The fluorescent nuclear staining may be performed with a variety of cell permeable nuclear dyes, enabling the technique to be performed with multiple standard microscope/illumination or confocal/laser systems. The method may be used to document morphology of embryos of a variety of organisms, as well as individual organs and tissues. Nuclear stain imaging imposes minimal impact on embryonic specimens, enabling imaged specimens to be utilized for additional assays. PMID:22930523

Whole mount nuclear fluorescent imaging: convenient documentation of embryo morphology.

PubMed

Sandell, Lisa L; Kurosaka, Hiroshi; Trainor, Paul A

2012-11-01

Here, we describe a relatively inexpensive and easy method to produce high quality images that reveal fine topological details of vertebrate embryonic structures. The method relies on nuclear staining of whole mount embryos in combination with confocal microscopy or conventional wide field fluorescent microscopy. In cases where confocal microscopy is used in combination with whole mount nuclear staining, the resulting embryo images can rival the clarity and resolution of images produced by scanning electron microscopy (SEM). The fluorescent nuclear staining may be performed with a variety of cell permeable nuclear dyes, enabling the technique to be performed with multiple standard microscope/illumination or confocal/laser systems. The method may be used to document morphology of embryos of a variety of organisms, as well as individual organs and tissues. Nuclear stain imaging imposes minimal impact on embryonic specimens, enabling imaged specimens to be utilized for additional assays. Copyright © 2012 Wiley Periodicals, Inc.

Multiple markers and multiple individuals refine true seal phylogeny and bring molecules and morphology back in line.

PubMed

Fulton, Tara Lynn; Strobeck, Curtis

2010-04-07

Despite decades of study, some aspects of Phocidae (Pinnipedia, Carnivora) phylogeny still remain unresolved. Using the largest novel dataset to date, including all extant phocids and comprising 15 nuclear and 13 mitochondrial genes, we illustrate the utility of including multiple individuals per species in resolving rapid radiations, and provide new insight into phocid phylogeny. In line with longstanding morphological views, Pusa is recovered as monophyletic for the first time with genetic data. The data are also used to explore the relationship between genetic distance and taxonomic rank. Intraspecific sampling also highlights the discrepancy between molecular and morphological rates of evolution within Phocidae.

Analysis of the genetic phylogeny of multifocal prostate cancer identifies multiple independent clonal expansions in neoplastic and morphologically normal prostate tissue.

PubMed

Cooper, Colin S; Eeles, Rosalind; Wedge, David C; Van Loo, Peter; Gundem, Gunes; Alexandrov, Ludmil B; Kremeyer, Barbara; Butler, Adam; Lynch, Andrew G; Camacho, Niedzica; Massie, Charlie E; Kay, Jonathan; Luxton, Hayley J; Edwards, Sandra; Kote-Jarai, ZSofia; Dennis, Nening; Merson, Sue; Leongamornlert, Daniel; Zamora, Jorge; Corbishley, Cathy; Thomas, Sarah; Nik-Zainal, Serena; O'Meara, Sarah; Matthews, Lucy; Clark, Jeremy; Hurst, Rachel; Mithen, Richard; Bristow, Robert G; Boutros, Paul C; Fraser, Michael; Cooke, Susanna; Raine, Keiran; Jones, David; Menzies, Andrew; Stebbings, Lucy; Hinton, Jon; Teague, Jon; McLaren, Stuart; Mudie, Laura; Hardy, Claire; Anderson, Elizabeth; Joseph, Olivia; Goody, Victoria; Robinson, Ben; Maddison, Mark; Gamble, Stephen; Greenman, Christopher; Berney, Dan; Hazell, Steven; Livni, Naomi; Fisher, Cyril; Ogden, Christopher; Kumar, Pardeep; Thompson, Alan; Woodhouse, Christopher; Nicol, David; Mayer, Erik; Dudderidge, Tim; Shah, Nimish C; Gnanapragasam, Vincent; Voet, Thierry; Campbell, Peter; Futreal, Andrew; Easton, Douglas; Warren, Anne Y; Foster, Christopher S; Stratton, Michael R; Whitaker, Hayley C; McDermott, Ultan; Brewer, Daniel S; Neal, David E

2015-04-01

Genome-wide DNA sequencing was used to decrypt the phylogeny of multiple samples from distinct areas of cancer and morphologically normal tissue taken from the prostates of three men. Mutations were present at high levels in morphologically normal tissue distant from the cancer, reflecting clonal expansions, and the underlying mutational processes at work in morphologically normal tissue were also at work in cancer. Our observations demonstrate the existence of ongoing abnormal mutational processes, consistent with field effects, underlying carcinogenesis. This mechanism gives rise to extensive branching evolution and cancer clone mixing, as exemplified by the coexistence of multiple cancer lineages harboring distinct ERG fusions within a single cancer nodule. Subsets of mutations were shared either by morphologically normal and malignant tissues or between different ERG lineages, indicating earlier or separate clonal cell expansions. Our observations inform on the origin of multifocal disease and have implications for prostate cancer therapy in individual cases.

Alterations in blood-brain barrier function following acute hypertension: comparison of the blood-to-brain transfer of horseradish peroxidase with that of alpha-aminisobutyric acid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ellison, M.D.B.

The blood-brain barrier (BBB) selectively restricts the blood-to-brain passage of many solutes owing to unique properties of cerebrovascular endothelial cell membranes. To date, experimental study of the BBB has been accomplished primarily through the use of two different methodological approaches. Morphological studies have mostly employed large molecular weight (MW) tracers to detect morphological alterations underlying increased permeability. Physiological studies, employing smaller, more physiologic tracers have successfully described, quantitatively, certain functional aspects of blood-to-brain transfer. The current work attempts to merge these two approaches and to consider barrier function/dysfunction from both a morphological and a functional perspective. Specifically, the study comparesmore » in rats, following acute hypertension, the cerebrovascular passage of /sup 14/C-alpha-aminoisobutyric acid (AIB) and that of horseradish peroxidase (HRP). The blood-to-brain passage of AIB and HRP were compared following acute hypertension, with regard to both the distributions of the tracer extravasation patterns and the magnitude of tracer extravasation. The results of this study suggest that traditional morphological barrier studies alone do not reveal all aspects of altered barrier status and that multiple mechanisms underlying increased BBB permeability may operate simultaneously during BBB dysfunction.« less

Is floral specialization an evolutionary dead-end? Pollination system transitions in Ruellia (Acanthaceae).

PubMed

Tripp, Erin A; Manos, Paul S

2008-07-01

Pollination systems frequently reflect adaptations to particular groups of pollinators. Such systems are indicative of evolutionary specialization and have been important in angiosperm diversification. We studied the evolution of pollination systems in the large genus Ruellia. Phylogenetic analyses, morphological ordinations, ancestral state reconstructions, and a character mapping simulation were conducted to reveal key patterns in the direction and lability of floral characters associated with pollination. We found significant floral morphological differences among species that were generally associated with different groups of floral visitors. Floral evolution has been highly labile and also directional. Some specialized systems such as hawkmoth or bat pollination are likely evolutionary dead-ends. In contrast, specialized pollination by hummingbirds is clearly not a dead-end. We found evidence for multiple reverse transitions from presumed ancestral hummingbird pollination to more derived bee or insect pollination. These repeated origins of insect pollination from hummingbird-pollinated ancestors have not evolved without historical baggage. Flowers of insect-pollinated species derived from hummingbird-pollinated ancestors are morphologically more similar to hummingbird flowers than they are to other more distantly related insect-pollinated flowers. Finally, some pollinator switches were concomitant with changes in floral morphology that are associated with those pollinators. These observations are consistent with the hypothesis that some transitions have been adaptive in the evolution of Ruellia.

Loss of YABBY2-Like Gene Expression May Underlie the Evolution of the Laminar Style in Canna and Contribute to Floral Morphological Diversity in the Zingiberales.

PubMed

Morioka, Kelsie; Yockteng, Roxana; Almeida, Ana M R; Specht, Chelsea D

2015-01-01

The Zingiberales is an order of tropical monocots that exhibits diverse floral morphologies. The evolution of petaloid, laminar stamens, staminodes, and styles contributes to this diversity. The laminar style is a derived trait in the family Cannaceae and plays an important role in pollination as its surface is used for secondary pollen presentation. Previous work in the Zingiberales has implicated YABBY2-like genes, which function in promoting laminar outgrowth, in the evolution of stamen morphology. Here, we investigate the evolution and expression of Zingiberales YABBY2-like genes in order to understand the evolution of the laminar style in Canna. Phylogenetic analyses show that multiple duplication events have occurred in this gene lineage prior to the diversification of the Zingiberales. Reverse transcription-PCR in Canna, Costus, and Musa reveals differential expression across floral organs, taxa, and gene copies, and a role for YABBY2-like genes in the evolution of the laminar style is proposed. Selection tests indicate that almost all sites in conserved domains are under purifying selection, consistent with their functional relevance, and a motif unique to monocot YABBY2-like genes is identified. These results contribute to our understanding of the molecular mechanisms underlying the evolution of floral morphologies.

Loss of YABBY2-Like Gene Expression May Underlie the Evolution of the Laminar Style in Canna and Contribute to Floral Morphological Diversity in the Zingiberales

PubMed Central

Morioka, Kelsie; Yockteng, Roxana; Almeida, Ana M. R.; Specht, Chelsea D.

2015-01-01

The Zingiberales is an order of tropical monocots that exhibits diverse floral morphologies. The evolution of petaloid, laminar stamens, staminodes, and styles contributes to this diversity. The laminar style is a derived trait in the family Cannaceae and plays an important role in pollination as its surface is used for secondary pollen presentation. Previous work in the Zingiberales has implicated YABBY2-like genes, which function in promoting laminar outgrowth, in the evolution of stamen morphology. Here, we investigate the evolution and expression of Zingiberales YABBY2-like genes in order to understand the evolution of the laminar style in Canna. Phylogenetic analyses show that multiple duplication events have occurred in this gene lineage prior to the diversification of the Zingiberales. Reverse transcription-PCR in Canna, Costus, and Musa reveals differential expression across floral organs, taxa, and gene copies, and a role for YABBY2-like genes in the evolution of the laminar style is proposed. Selection tests indicate that almost all sites in conserved domains are under purifying selection, consistent with their functional relevance, and a motif unique to monocot YABBY2-like genes is identified. These results contribute to our understanding of the molecular mechanisms underlying the evolution of floral morphologies. PMID:26734021

Inherent interfacial mechanical gradients in 3D hydrogels influence tumor cell behaviors.

PubMed

Rao, Shreyas S; Bentil, Sarah; DeJesus, Jessica; Larison, John; Hissong, Alex; Dupaix, Rebecca; Sarkar, Atom; Winter, Jessica O

2012-01-01

Cells sense and respond to the rigidity of their microenvironment by altering their morphology and migration behavior. To examine this response, hydrogels with a range of moduli or mechanical gradients have been developed. Here, we show that edge effects inherent in hydrogels supported on rigid substrates also influence cell behavior. A Matrigel hydrogel was supported on a rigid glass substrate, an interface which computational techniques revealed to yield relative stiffening close to the rigid substrate support. To explore the influence of these gradients in 3D, hydrogels of varying Matrigel content were synthesized and the morphology, spreading, actin organization, and migration of glioblastoma multiforme (GBM) tumor cells were examined at the lowest (<50 µm) and highest (>500 µm) gel positions. GBMs adopted bipolar morphologies, displayed actin stress fiber formation, and evidenced fast, mesenchymal migration close to the substrate, whereas away from the interface, they adopted more rounded or ellipsoid morphologies, displayed poor actin architecture, and evidenced slow migration with some amoeboid characteristics. Mechanical gradients produced via edge effects could be observed with other hydrogels and substrates and permit observation of responses to multiple mechanical environments in a single hydrogel. Thus, hydrogel-support edge effects could be used to explore mechanosensitivity in a single 3D hydrogel system and should be considered in 3D hydrogel cell culture systems.

Co-infections of the cestode Echinococcus vogeli and the nematode Calodium hepaticum in the hystricomorphic rodent Agouti paca from a forest reserve in Acre, Brazil.

PubMed

Almeida, F; Caldas, R; Corrêa, C; Rodrigues-Silva, R; Siqueira, N; Machado-Silva, J R

2013-12-01

The helminth fauna of Agouti paca (Linnaeus, 1766) has seldom been studied. In this paper, we report an unusual mixed infection of Echinococcus vogeli Rausch & Bernstein, 1972 and Calodium hepaticum (syn. Capillaria hepatica Bancroft, 1863) in free-ranging paca from a forested region in Acre (Brazil). Gross morphological examination revealed that paca liver contained multiple spherical to subspherical white or translucent lesions, which were isolated or frequently contiguous and partially covered by Glisson's capsule. Microscopic examination revealed unilocular cystic structures that contained abundant brood capsules in which numerous protoscolices budded from the inner surface. The protoscolices possessed rostellar hooks (33-41 μm in length), a morphological characteristic of the blade and calcareous corpuscles that is consistent with the metacestode E. vogeli. The diagnosis of C. hepaticum infection was based on the morphology and morphometry of the egg-shaped ellipsoids with bipolar plugs (44.8 ± 1.9 μm (length) × 24.4 ± 2.0 μm (width)) and liver histopathology. This finding expands the known range of C. hepaticum hosts in South America and, to the best of our knowledge, it is the first case of a mixed infection of E. vogeli and C. hepaticum. Furthermore, our data provide evidence that wild animal meat may be a source of C. hepaticum infection.

Integrating multiple evidences in taxonomy: species diversity and phylogeny of mustached bats (Mormoopidae: Pteronotus).

PubMed

Pavan, Ana Carolina; Marroig, Gabriel

2016-10-01

A phylogenetic systematic perspective is instrumental in recovering new species and their evolutionary relationships. The advent of new technologies for molecular and morphological data acquisition and analysis, allied to the integration of knowledge from different areas, such as ecology and population genetics, allows for the emergence of more rigorous, accurate and complete scientific hypothesis on species diversity. Mustached bats (genus Pteronotus) are a good model for the application of this integrative approach. They are a widely distributed and a morphologically homogeneous group, but comprising species with remarkable differences in their echolocation strategy and feeding behavior. The latest systematic review suggested six species with 17 subspecies in Pteronotus. Subsequent studies using discrete morphological characters supported the same arrangement. However, recent papers reported high levels of genetic divergence among conspecific taxa followed by bioacoustic and geographic agreement, suggesting an underestimated diversity in the genus. To date, no study merging genetic evidences and morphometric variation along the entire geographic range of this group has been attempted. Based on a comprehensive sampling including representatives of all current taxonomic units, we attempt to delimit species in Pteronotus through the application of multiple methodologies and hierarchically distinct datasets. The molecular approach includes six molecular markers from three genetic transmission systems; morphological investigations used 41 euclidean distances estimated through three-dimensional landmarks collected from 1628 skulls. The phylogenetic analysis reveals a greater diversity than previously reported, with a high correspondence among the genetic lineages and the currently recognized subspecies in the genus. Discriminant analysis of variables describing size and shape of cranial bones support the rising of the genetic groups to the specific status. Based on multiples evidences, we present an updated taxonomic arrangement composed by 16 extant species and a new and more robust phylogenetic hypothesis for the species included in the genus Pteronotus. Studies developed under such integrative taxonomic approach are timely for a deeper and wider comprehension of Neotropical diversity, representing the first step for answering broader questions on evolutionary and ecological aspects of Neotropical life history. Copyright © 2016 Elsevier Inc. All rights reserved.

COI haplotype groups in Mesocriconema (Nematoda: Criconematidae) and their morphospecies associations.

PubMed

Powers, T O; Bernard, E C; Harris, T; Higgins, R; Olson, M; Lodema, M; Mullin, P; Sutton, L; Powers, K S

2014-07-03

Without applying an a priori bias for species boundaries, specimen identities in the plant-parasitic nematode genus Mesocriconema were evaluated by examining mitochondrial COI nucleotide sequences, morphology, and biogeography. A total of 242 specimens that morphologically conformed to the genus were individually photographed, measured, and amplified by a PCR primer set to preserve the linkage between specimen morphology and a specific DNA barcode sequence. Specimens were extracted from soil samples representing 45 locations across 23 ecoregions in North America. Dendrograms constructed by neighbor-joining, maximum likelihood, and Bayesian Inference using a 721-bp COI barcode were used to group COI haplotypes. Each tree-building approach resulted in 24 major haplotype groups within the dataset. The distinctiveness of these groups was evaluated by node support, genetic distance, absence of intermediates, and several measures of distinctiveness included in software used for the exploration of species boundaries. Five of the 24 COI haplotype groups corresponded to morphologically characterized, Linnaean species. Morphospecies conforming to M. discus, Discocriconemella inarata, M. rusticum, M. onoense, and M. kirjanovae were represented by groups composed of multiple closely related or identical COI haplotypes. In other cases, morphospecies names could be equally applied to multiple haplotype groups that were genetically distant from each other. Identification based on morphology alone resulted in M. curvatum and M. ornatum species designations applied to seven and three groups, respectively. Morphological characters typically used for species level identification were demonstrably variable within haplotype groups, suggesting caution in assigning species names based on published compendia that solely consider morphological characters. Morphospecies classified as M. xenoplax formed a monophyletic group composed of seven genetically distinct COI subgroups. The species Discocriconemella inarata is transferred to Mesocriconema inaratum based on its phylogenetic position on the COI tree as well as previous phylogenetic analyses using 18S, ITS1, and cytochrome b nucleotide sequences. This study indicates that some of the species considered cosmopolitan in their distribution are actually multispecies polyphyletic groupings and an accurate assessment of Mesocriconema species distributions will benefit from molecular determination of haplotype relationships. The groups revealed by COI analysis should provide a useful framework for the evaluation of additional Mesocriconema species and will improve the reliability of designating taxonomic units in studies of nematode biodiversity. 

Phylogenetics of Australasian gall flies (Diptera: Fergusoninidae): Evolutionary patterns of host-shifting and gall morphology.

PubMed

Scheffer, S J; Davies, K A; Taylor, G S; Thornhill, A H; Lewis, M L; Winkler, I S; Yeates, D K; Purcell, M F; Makinson, J; Giblin-Davis, R M

2017-10-01

This study investigated host-specificity and phylogenetic relationships in Australian galling flies, Fergusonina Malloch (Diptera: Fergusoninidae), in order to assess diversity and explore the evolutionary history of host plant affiliation and gall morphology. A DNA barcoding approach using COI data from 203 Fergusonina specimens from 5gall types on 56 host plant species indicated 85 presumptive fly species. These exhibited a high degree of host specificity; of the 40 species with multiple representatives, each fed only on a single host genus, 29 (72.5%) were strictly monophagous, and 11 (27.5%) were reared from multiple closely related hosts. COI variation within species was not correlated with either sample size or geographic distance. However variation was greater within oligophagous species, consistent with expectations of the initial stages of host-associated divergence during speciation. Phylogenetic analysis using both nuclear and mitochondrial genes revealed host genus-restricted clades but also clear evidence of multiple colonizations of both host plant genus and host species. With the exception of unilocular peagalls, evolution of gall type was somewhat constrained, but to a lesser degree than host plant association. Unilocular peagalls arose more often than any other gall type, were primarily located at the tips of the phylogeny, and did not form clades comprising more than a few species. For ecological reasons, species of this gall type are predicted to harbor substantially less genetic variation than others, possibly reducing evolutionary flexibility resulting in reduced diversification in unilocular gallers. Published by Elsevier Inc.

Quaternary organic solar cells enhanced by cocrystalline squaraines with power conversion efficiencies >10%

DOE PAGES

Goh, Tenghooi; Huang, Jing -Shun; Yager, Kevin G.; ...

2016-08-11

The incorporation of multiple donors into the bulk-heterojunction layer of organic polymer solar cells (PSCs) has been demonstrated as a practical and elegant strategy to improve photovoltaics performance. However, it is challenging to successfully design and blend multiple donors, while minimizing unfavorable interactions (e.g., morphological traps, recombination centers, etc.). Here, a new Förster resonance energy transfer-based design is shown utilizing the synergistic nature of three light active donors (two small molecules and a high-performance donor–acceptor polymer) with a fullerene acceptor to create highly efficient quaternary PSCs with power conversion efficiencies (PCEs) of up to 10.7%. Within this quaternary architecture, itmore » is revealed that the addition of small molecules in low concentrations broadens the absorption bandwidth, induces cocrystalline molecular conformations, and promotes rapid (picosecond) energy transfer processes. Finally, these results provide guidance for the design of multiple-donor systems using simple processing techniques to realize single-junction PSC designs with unprecedented PCEs.« less

Refractory Cushing's disease caused by multinodular ACTH-cell hyperplasia.

PubMed

McKeever, P E; Koppelman, M C; Metcalf, D; Quindlen, E; Kornblith, P L; Strott, C A; Howard, R; Smith, B H

1982-09-01

A patient with pituitary-dependent hypercortisolism, unresponsive to resection of nodules in the anterior lobe, is described. Histochemical stains of the nodules showed multiple, focal, cellular expansions of the fibrovascular stroma. Transitions between normal and expanded adenohypophysial acini were present. Immunoperoxidase stains for ACTH and other pituitary hormones revealed that these multiple foci contained an excess of ACTH-positive cells. Less than 10% of the cells in these foci were negative for ACTH and positive for other hormones. Serial sections showed that these foci of predominantly ACTH-producing acini were not connected. Clinical, morphological, and immunohistochemical data indicated that ACTH-cell hyperplasia caused Crushing's disease in this patient. Pathologic study of individual cases should concentrate on determining whether hyperplasia or adenoma exist at the time of surgical exploration of the pituitary gland, since this determination is important to proper treatment. Tentative criteria to recognize ACTH-cell hyperplasia are: 1. Multiple foci of ACTH laden cells. 2. A minor subpopulation of cells of alternate hormone series. 3. Expansion without destruction of acini in the adenohypophysis.

2.8 {mu}m emission from type-I quantum wells grown on InAs{sub x}P{sub 1-x}/InP metamorphic graded buffers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jung, Daehwan; Song, Yuncheng; Larry Lee, Minjoo

We report 2.8 {mu}m emission from compressively strained type-I quantum wells (QWs) grown on InP-based metamorphic InAs{sub x}P{sub 1-x} step-graded buffers. High quality metamorphic graded buffers showed smooth surface morphology and low threading dislocation densities of approximately 2.5 Multiplication-Sign 10{sup 6} cm{sup -2}. High-resolution x-ray diffraction scans showed strong satellites from multiple quantum wells grown on metamorphic buffers, and cross-sectional transmission electron microscopy revealed smooth and coherent quantum well interfaces. Room-temperature photoluminescence emission at 2.8 {mu}m with a narrow linewidth ({approx}50 meV) shows the promise of metamorphic growth for mid-infrared laser diodes on InP.

Morphology and Efficiency of a Specialized Foraging Behavior, Sediment Sifting, in Neotropical Cichlid Fishes

PubMed Central

Willis, Stuart; Watkins, Crystal; Honeycutt, Rodney L.; Winemiller, Kirk O.

2014-01-01

Understanding of relationships between morphology and ecological performance can help to reveal how natural selection drives biological diversification. We investigate relationships between feeding behavior, foraging performance and morphology within a diverse group of teleost fishes, and examine the extent to which associations can be explained by evolutionary relatedness. Morphological adaptation associated with sediment sifting was examined using a phylogenetic linear discriminant analysis on a set of ecomorphological traits from 27 species of Neotropical cichlids. For most sifting taxa, feeding behavior could be effectively predicted by a linear discriminant function of ecomorphology across multiple clades of sediment sifters, and this pattern could not be explained by shared evolutionary history alone. Additionally, we tested foraging efficiency in seven Neotropical cichlid species, five of which are specialized benthic feeders with differing head morphology. Efficiency was evaluated based on the degree to which invertebrate prey could be retrieved at different depths of sediment. Feeding performance was compared both with respect to feeding mode and species using a phylogenetic ANCOVA, with substrate depth as a covariate. Benthic foraging performance was constant across sediment depths in non-sifters but declined with depth in sifters. The non-sifting Hypsophrys used sweeping motions of the body and fins to excavate large pits to uncover prey; this tactic was more efficient for consuming deeply buried invertebrates than observed among sediment sifters. Findings indicate that similar feeding performance among sediment-sifting cichlids extracting invertebrate prey from shallow sediment layers reflects constraints associated with functional morphology and, to a lesser extent, phylogeny. PMID:24603485

Morphology and efficiency of a specialized foraging behavior, sediment sifting, in neotropical cichlid fishes.

PubMed

López-Fernández, Hernán; Arbour, Jessica; Willis, Stuart; Watkins, Crystal; Honeycutt, Rodney L; Winemiller, Kirk O

2014-01-01

Understanding of relationships between morphology and ecological performance can help to reveal how natural selection drives biological diversification. We investigate relationships between feeding behavior, foraging performance and morphology within a diverse group of teleost fishes, and examine the extent to which associations can be explained by evolutionary relatedness. Morphological adaptation associated with sediment sifting was examined using a phylogenetic linear discriminant analysis on a set of ecomorphological traits from 27 species of Neotropical cichlids. For most sifting taxa, feeding behavior could be effectively predicted by a linear discriminant function of ecomorphology across multiple clades of sediment sifters, and this pattern could not be explained by shared evolutionary history alone. Additionally, we tested foraging efficiency in seven Neotropical cichlid species, five of which are specialized benthic feeders with differing head morphology. Efficiency was evaluated based on the degree to which invertebrate prey could be retrieved at different depths of sediment. Feeding performance was compared both with respect to feeding mode and species using a phylogenetic ANCOVA, with substrate depth as a covariate. Benthic foraging performance was constant across sediment depths in non-sifters but declined with depth in sifters. The non-sifting Hypsophrys used sweeping motions of the body and fins to excavate large pits to uncover prey; this tactic was more efficient for consuming deeply buried invertebrates than observed among sediment sifters. Findings indicate that similar feeding performance among sediment-sifting cichlids extracting invertebrate prey from shallow sediment layers reflects constraints associated with functional morphology and, to a lesser extent, phylogeny.

Examining the Underlying Dimensions of Morphological Awareness and Vocabulary Knowledge

ERIC Educational Resources Information Center

Spencer, Mercedes; Muse, Andrea; Wagner, Richard K.; Foorman, Barbara; Petscher, Yaacov; Schatschneider, Christopher; Tighe, Elizabeth L.; Bishop, M. Denise

2015-01-01

We report results from two studies on the underlying dimensions of morphological awareness and vocabulary knowledge in elementary-aged children. In Study 1, 99 fourth-grade students were given multiple measures of morphological awareness and vocabulary. A single factor accounted for individual differences in all morphology and vocabulary…

Phylogenetic Diversity, Distribution, and Cophylogeny of Giant Bacteria (Epulopiscium) with their Surgeonfish Hosts in the Red Sea

PubMed Central

Miyake, Sou; Ngugi, David K.; Stingl, Ulrich

2016-01-01

Epulopiscium is a group of giant bacteria found in high abundance in intestinal tracts of herbivorous surgeonfish. Despite their peculiarly large cell size (can be up to 600 μm), extreme polyploidy (some with over 100,000 genome copies per cell) and viviparity (whereby mother cells produce live offspring), details about their diversity, distribution or their role in the host gut are lacking. Previous studies have highlighted the existence of morphologically distinct Epulopiscium cell types (defined as morphotypes A to J) in some surgeonfish genera, but the corresponding genetic diversity and distribution among other surgeonfishes remain mostly unknown. Therefore, we investigated the phylogenetic diversity of Epulopiscium, distribution and co-occurrence in multiple hosts. Here, we identified eleven new phylogenetic clades, six of which were also morphologically characterized. Three of these novel clades were phylogenetically and morphologically similar to cigar-shaped type A1 cells, found in a wide range of surgeonfishes including Acanthurus nigrofuscus, while three were similar to smaller, rod-shaped type E that has not been phylogenetically classified thus far. Our results also confirmed that biogeography appears to have relatively little influence on Epulopiscium diversity, as clades found in the Great Barrier Reef and Hawaii were also recovered from the Red Sea. Although multiple symbiont clades inhabited a given species of host surgeonfish and multiple host species possessed a given symbiont clade, statistical analysis of host and symbiont phylogenies indicated significant cophylogeny, which in turn suggests co-evolutionary relationships. A cluster analysis of Epulopiscium sequences from previously published amplicon sequencing dataset revealed a similar pattern, where specific clades were consistently found in high abundance amongst closely related surgeonfishes. Differences in abundance may indicate specialization of clades to certain gut environments reflected by inferred differences in the host diets. Overall, our analysis identified a large phylogenetic diversity of Epulopiscium (up to 10% sequence divergence of 16S rRNA genes), which lets us hypothesize that there are multiple species that are spread across guts of different host species. PMID:27014209

Supertoughened renewable PLA reactive multiphase blends system: phase morphology and performance.

PubMed

Zhang, Kunyu; Nagarajan, Vidhya; Misra, Manjusri; Mohanty, Amar K

2014-08-13

Multiphase blends of poly(lactic acid) (PLA), ethylene-methyl acrylate-glycidyl methacrylate (EMA-GMA) terpolymer, and a series of renewable poly(ether-b-amide) elastomeric copolymer (PEBA) were fabricated through reactive melt blending in an effort to improve the toughness of the PLA. Supertoughened PLA blend showing impact strength of ∼500 J/m with partial break impact behavior was achieved at an optimized blending ratio of 70 wt % PLA, 20 wt % EMA-GMA, and 10 wt % PEBA. Miscibility and thermal behavior of the binary blends PLA/PEBA and PLA/EMA-GMA, and the multiphase blends were also investigated through differential scanning calorimetric (DSC) and dynamic mechanical analysis (DMA). Phase morphology and fracture surface morphology of the blends were studied through scanning electron microscopy (SEM) and atomic force microscopy (AFM) to understand the strong corelation between the morphology and its significant effect on imparting tremendous improvement in toughness. A unique "multiple stacked structure" with partial encapsulation of EMA-GMA and PEBA minor phases was observed for the PLA/EMA-GMA/PEBA (70/20/10) revealing the importance of particular blend composition in enhancing the toughness. Toughening mechanism behind the supertoughened PLA blends have been established by studying the impact fractured surface morphology at different zones of fracture. Synergistic effect of good interfacial adhesion and interfacial cavitations followed by massive shear yielding of the matrix was believed to contribute to the enormous toughening effect observed in these multiphase blends.

Numerical Simulations of Silverpit Crater Collapse

NASA Technical Reports Server (NTRS)

Collins, G. S.; Turtle, E. P.; Melosh, H. J.

2003-01-01

The Silverpit crater is a recently discovered, 60-65 Myr old complex crater, which lies buried beneath the North Sea, about 150 km east of Britain. High-resolution images of Silverpit's subsurface structure, provided by three-dimensional seismic reflection data, reveal an inner-crater morphology similar to that expected for a 5-8 km diameter terrestrial crater. The crater walls show evidence of terracestyle slumping and there is a distinct central uplift, which may have produced a central peak in the pristine crater morphology. However, Silverpit is not a typical 5-km diameter terrestrial crater, because it exhibits multiple, concentric rings outside the main cavity. External concentric rings are normally associated with much larger impact structures, for example Chicxulub on Earth, or Orientale on the Moon. Furthermore, external rings associated with large impacts on the terrestrial planets and moons are widely-spaced, predominantly inwardly-facing, asymmetric scarps. However, the seismic data show that the external rings at Silverpit represent closely-spaced, concentric fault-bound graben, with both inwardly and outwardly facing faults-carps. This type of multi-ring structure is directly analogous to the Valhalla-type multi-ring basins found on the icy satellites. Thus, the presence and style of the multiple rings at Silverpit is surprising given both the size of the crater and its planetary setting.

[MRT of the liver in Wilson's disease].

PubMed

Vogl, T J; Steiner, S; Hammerstingl, R; Schwarz, S; Kraft, E; Weinzierl, M; Felix, R

1994-01-01

To show that Wilson's disease is one likely cause of multiple low-intensity nodules of the liver we obtained MR images in 16 patients with clinically and histopathologically confirmed Wilson's disease. Corresponding to morphological changes MRI enabled the subdivision of the patients into two groups. Using a T2-weighted spin-echo sequence (TR/TE = 2000/45-90) liver parenchyma showed multiple tiny low-intensity-nodules surrounded by high-intensity septa in 10 out of 16 patients. 5 patients had also low-intensity nodules in T1-weighted images (TR/TE = 600/20). In patients of this group histopathology revealed liver cirrhosis (n = 7) and fibrosis (n = 2). Common feature of this patient group was marked inflammatory cell infiltration into fibrous septa, increase of copper concentration in liver parenchyma and distinct pathological changes of laboratory data. In the remaining 6 patients no pathological change of liver morphology was demonstrated by MRI corresponding to slight histopathological changes of parenchyma and normal laboratory data. As low-intensity nodules surrounded by high intensity septa can be demonstrated in patients with marked inflammatory infiltration of liver parenchyma MRI may help to define Wilson patients with poorer prognosis. In patients with low-intensity nodules of the liver and unknown cause of liver cirrhosis laboratory data and histopathology should be checked when searching for disorders of copper metabolism.

Mapping quantitative trait loci for yield, yield components and morphological traits in an advanced backcross population between Oryza rufipogon and the Oryza sativa cultivar Jefferson.

PubMed

Thomson, M J; Tai, T H; McClung, A M; Lai, X-H; Hinga, M E; Lobos, K B; Xu, Y; Martinez, C P; McCouch, S R

2003-08-01

An advanced backcross population between an accession of Oryza rufipogon (IRGC 105491) and the U.S. cultivar Jefferson (Oryza sativa ssp. japonica) was developed to identify quantitative trait loci (QTLs) for yield, yield components and morphological traits. The genetic linkage map generated for this population consisted of 153 SSR and RFLP markers with an average interval size of 10.3 cM. Thirteen traits were examined, nine of which were measured in multiple environments. Seventy-six QTLs above an experiment-wise significance threshold of P<0.01 (corresponding to an interval mapping LOD>3.6 or a composite interval mapping LOD>3.9) were identified. For the traits measured in multiple environments, 47% of the QTLs were detected in at least two environments. The O. rufipogon allele was favorable for 53% of the yield and yield component QTLs, including loci for yield, grains per panicle, panicle length, and grain weight. Morphological traits related to the domestication process and/or weedy characteristics, including plant height, shattering, tiller type and awns, were found clustered on chromosomes 1 and 4. Comparisons to previous studies involving wild x cultivated crosses revealed O. rufipogon alleles with stable effects in multiple genetic backgrounds and environments, several of which have not been detected in studies between Oryza sativa cultivars, indicating potentially novel alleles from O. rufipogon. Some O. rufipogon-derived QTLs, however, were in similar regions as previously reported QTLs from Oryza sativa cultivars, providing evidence for conservation of these QTLs across the Oryza genus. In addition, several QTLs for grain weight, plant height, and flowering time were localized to putative homeologous regions in maize where QTLs for these traits have been previously reported, supporting the hypothesis of functional conservation of QTLs across the grasses.

Complex within a Complex: Integrative Taxonomy Reveals Hidden Diversity in Cicadetta brevipennis (Hemiptera: Cicadidae) and Unexpected Relationships with a Song Divergent Relative.

PubMed

Hertach, Thomas; Puissant, Stéphane; Gogala, Matija; Trilar, Tomi; Hagmann, Reto; Baur, Hannes; Kunz, Gernot; Wade, Elizabeth J; Loader, Simon P; Simon, Chris; Nagel, Peter

2016-01-01

Multiple sources of data in combination are essential for species delimitation and classification of difficult taxonomic groups. Here we investigate a cicada taxon with unusual cryptic diversity and we attempt to resolve seemingly contradictory data sets. Cicada songs act as species-specific premating barriers and have been used extensively to reveal hidden taxonomic diversity in morphologically similar species. The Palaearctic Cicadetta montana species complex is an excellent example where distinct song patterns have disclosed multiple recently described species. Indeed, two taxa turned out to be especially diverse in that they form a "complex within the complex": the Cicadetta cerdaniensis song group (four species studied previously) and Cicadetta brevipennis (examined in details here). Based on acoustic, morphological, molecular, ecological and spatial data sampled throughout their broad European distribution, we find that Cicadetta brevipennis s. l. comprises five lineages. The most distinct lineage is identified as Cicadetta petryi Schumacher, 1924, which we re-assign to the species level. Cicadetta brevipennis litoralis Puissant & Hertach ssp. n. and Cicadetta brevipennis hippolaidica Hertach ssp. n. are new to science. The latter hybridizes with Cicadetta brevipennis brevipennis Fieber, 1876 at a zone inferred from intermediate song patterns. The fifth lineage requires additional investigation. The C. cerdaniensis and the C. brevipennis song groups exhibit characteristic, clearly distinct basic song patterns that act as reproductive barriers. However, they remain completely intermixed in the Bayesian and maximum likelihood COI and COII mitochondrial DNA phylogenies. The closest relative of each of the four cerdaniensis group species is a brevipennis group taxon. In our favoured scenario the phylogenetic pairs originated in common Pleistocene glacial refuges where the taxa speciated and experienced sporadic inter-group hybridization leading to extensive introgression and mitochondrial capture.

Phylogeographic study of Chinese seabuckthorn (Hippophae rhamnoides subsp. sinensis Rousi) reveals two distinct haplotype groups and multiple microrefugia on the Qinghai-Tibet Plateau

PubMed Central

Wang, Hongfang; Liu, Han; Yang, Mingbo; Bao, Lei; Ge, Jianping

2014-01-01

Historical climate change can shape the genetic pattern of a species. Studies on this phenomenon provide great advantage in predicting the response of species to current and future global climate change. Chinese seabuckthorn (Hippophae rhamnoides subsp. sinensis) is one of the most important cultivated plants in Northwest China. However, the subspecies history and the potential genetic resources within the subspecies range remain unclear. In this study, we utilized two intergenic chloroplast regions to characterize the spatial genetic distribution of the species. We found 19 haplotypes in total, 12 of which were unique to the Chinese seabuckthorn. The populations observed on the Qinghai-Tibet Plateau (QTP) consisted of most of the haplotypes, while in the northeast of the range of the subspecies, an area not on the QTP, only four haplotypes were detected. Our study also revealed two distinct haplotype groups of the subspecies with a sharp transition region located in the south of the Zoige Basin. 89.96% of the genetic variation located between the regions. Mismatch analysis indicated old expansions of these two haplotype groups, approximately around the early stage of Pleistocene. Additional morphological proofs from existing studies and habitat differentiation supported a long independent colonization history among the two regions. Potential adaptation probably occurred but needs more genome and morphology data in future. Chinese seabuckthorn have an older population expansion compared with subspecies in Europe. The lack of large land ice sheets and the heterogeneous landscape of the QTP could have provided extensive microrefugia for Chinese seabuckthorn during the glaciation period. Multiple localities sustaining high-frequency private haplotypes support this hypothesis. Our study gives clear insight into the distribution of genetic resources and the evolutionary history of Chinese seabuckthorn. PMID:25540697

Complex within a Complex: Integrative Taxonomy Reveals Hidden Diversity in Cicadetta brevipennis (Hemiptera: Cicadidae) and Unexpected Relationships with a Song Divergent Relative

PubMed Central

Hertach, Thomas; Puissant, Stéphane; Gogala, Matija; Trilar, Tomi; Hagmann, Reto; Baur, Hannes; Kunz, Gernot; Wade, Elizabeth J.; Loader, Simon P.; Simon, Chris; Nagel, Peter

2016-01-01

Multiple sources of data in combination are essential for species delimitation and classification of difficult taxonomic groups. Here we investigate a cicada taxon with unusual cryptic diversity and we attempt to resolve seemingly contradictory data sets. Cicada songs act as species-specific premating barriers and have been used extensively to reveal hidden taxonomic diversity in morphologically similar species. The Palaearctic Cicadetta montana species complex is an excellent example where distinct song patterns have disclosed multiple recently described species. Indeed, two taxa turned out to be especially diverse in that they form a “complex within the complex”: the Cicadetta cerdaniensis song group (four species studied previously) and Cicadetta brevipennis (examined in details here). Based on acoustic, morphological, molecular, ecological and spatial data sampled throughout their broad European distribution, we find that Cicadetta brevipennis s. l. comprises five lineages. The most distinct lineage is identified as Cicadetta petryi Schumacher, 1924, which we re-assign to the species level. Cicadetta brevipennis litoralis Puissant & Hertach ssp. n. and Cicadetta brevipennis hippolaidica Hertach ssp. n. are new to science. The latter hybridizes with Cicadetta brevipennis brevipennis Fieber, 1876 at a zone inferred from intermediate song patterns. The fifth lineage requires additional investigation. The C. cerdaniensis and the C. brevipennis song groups exhibit characteristic, clearly distinct basic song patterns that act as reproductive barriers. However, they remain completely intermixed in the Bayesian and maximum likelihood COI and COII mitochondrial DNA phylogenies. The closest relative of each of the four cerdaniensis group species is a brevipennis group taxon. In our favoured scenario the phylogenetic pairs originated in common Pleistocene glacial refuges where the taxa speciated and experienced sporadic inter-group hybridization leading to extensive introgression and mitochondrial capture. PMID:27851754

Rates of molecular evolution in tree ferns are associated with body size, environmental temperature, and biological productivity.

PubMed

Barrera-Redondo, Josué; Ramírez-Barahona, Santiago; Eguiarte, Luis E

2018-05-01

Variation in rates of molecular evolution (heterotachy) is a common phenomenon among plants. Although multiple theoretical models have been proposed, fundamental questions remain regarding the combined effects of ecological and morphological traits on rate heterogeneity. Here, we used tree ferns to explore the correlation between rates of molecular evolution in chloroplast DNA sequences and several morphological and environmental factors within a Bayesian framework. We revealed direct and indirect effects of body size, biological productivity, and temperature on substitution rates, where smaller tree ferns living in warmer and less productive environments tend to have faster rates of molecular evolution. In addition, we found that variation in the ratio of nonsynonymous to synonymous substitution rates (dN/dS) in the chloroplast rbcL gene was significantly correlated with ecological and morphological variables. Heterotachy in tree ferns may be influenced by effective population size associated with variation in body size and productivity. Macroevolutionary hypotheses should go beyond explaining heterotachy in terms of mutation rates and instead, should integrate population-level factors to better understand the processes affecting the tempo of evolution at the molecular level. © 2018 The Author(s). Evolution © 2018 The Society for the Study of Evolution.

Microchannel fabrication on cyclic olefin polymer substrates via 1064 nm Nd:YAG laser ablation

NASA Astrophysics Data System (ADS)

McCann, Ronán; Bagga, Komal; Groarke, Robert; Stalcup, Apryll; Vázquez, Mercedes; Brabazon, Dermot

2016-11-01

This paper presents a method for fabrication of microchannels on cyclic olefin polymer films that have application in the field of microfluidics and chemical sensing. Continuous microchannels were fabricated on 188-μm-thick cyclic olefin polymer substrates using a picosecond pulsed 1064 nm Nd:YAG laser. The effect of laser fluence on the microchannel morphology and dimensions was analysed via scanning electron microscopy and optical profilometry. Single laser passes were found to produce v-shaped microchannels with depths ranging from 12 μm to 47 μm and widths from 44 μm to 154 μm. The ablation rate during processing was lower than predicted theoretically. Multiple laser passes were applied to examine the ability for finer control over microchannel morphology with channel depths ranging from 22 μm to 77 μm and channel widths from 59 μm to 155 μm. For up to five repeat passes, acceptable reproducibility was found in the produced microchannel morphology. Infrared spectroscopy revealed oxidation and dehydrogenation of the polymer surface following laser ablation. These results were compared to other work conducted on cyclic olefin polymers.

The taming of the neural crest: a developmental perspective on the origins of morphological covariation in domesticated mammals

NASA Astrophysics Data System (ADS)

Sánchez-Villagra, Marcelo R.; Geiger, Madeleine; Schneider, Richard A.

2016-06-01

Studies on domestication are blooming, but the developmental bases for the generation of domestication traits and breed diversity remain largely unexplored. Some phenotypic patterns of human neurocristopathies are suggestive of those reported for domesticated mammals and disrupting neural crest developmental programmes have been argued to be the source of traits deemed the `domestication syndrome'. These character changes span multiple organ systems and morphological structures. But an in-depth examination within the phylogenetic framework of mammals including domesticated forms reveals that the distribution of such traits is not universal, with canids being the only group showing a large set of predicted features. Modularity of traits tied to phylogeny characterizes domesticated mammals: through selective breeding, individual behavioural and morphological traits can be reordered, truncated, augmented or deleted. Similarly, mammalian evolution on islands has resulted in suites of phenotypic changes like those of some domesticated forms. Many domesticated mammals can serve as valuable models for conducting comparative studies on the evolutionary developmental biology of the neural crest, given that series of their embryos are readily available and that their phylogenetic histories and genomes are well characterized.

Atypical nucleus accumbens morphology in psychopathy: another limbic piece in the puzzle.

PubMed

Boccardi, Marina; Bocchetta, Martina; Aronen, Hannu J; Repo-Tiihonen, Eila; Vaurio, Olli; Thompson, Paul M; Tiihonen, Jari; Frisoni, Giovanni B

2013-01-01

Psychopathy has been associated with increased putamen and striatum volumes. The nucleus accumbens - a key structure in reversal learning, less effective in psychopathy - has not yet received specific attention. Moreover, basal ganglia morphology has never been explored. We examined the morphology of the caudate, putamen and accumbens, manually segmented from magnetic resonance images of 26 offenders (age: 32.5 ± 8.4) with medium-high psychopathy (mean PCL-R=30 ± 5) and 25 healthy controls (age: 34.6 ± 10.8). Local differences were statistically modeled using a surface-based radial distance mapping method (p<0.05; multiple comparisons correction through permutation tests). In psychopathy, the caudate and putamen had normal global volume, but different morphology, significant after correction for multiple comparisons, for the right dorsal putamen (permutation test: p=0.02). The volume of the nucleus accumbens was 13% smaller in psychopathy (p corrected for multiple comparisons <0.006). The atypical morphology consisted of predominant anterior hypotrophy bilaterally (10-30%). Caudate and putamen local morphology displayed negative correlation with the lifestyle factor of the PCL-R (permutation test: p=0.05 and 0.03). From these data, psychopathy appears to be associated with an atypical striatal morphology, with highly significant global and local differences of the accumbens. This is consistent with the clinical syndrome and with theories of limbic involvement. Copyright © 2013 Elsevier Ltd. All rights reserved.

Computational Nonlinear Morphology with Emphasis on Semitic Languages. Studies in Natural Language Processing.

ERIC Educational Resources Information Center

Kiraz, George Anton

This book presents a tractable computational model that can cope with complex morphological operations, especially in Semitic languages, and less complex morphological systems present in Western languages. It outlines a new generalized regular rewrite rule system that uses multiple finite-state automata to cater to root-and-pattern morphology,…

Seafloor Structural Geomorphic Evolution in Response to Seamount Subduction, Poverty Bay Indentation, New Zealand

NASA Astrophysics Data System (ADS)

Bodger, K. L.; Pettinga, J. R.; Barnes, P. M.

2006-12-01

More than 4000 km2 of high quality bathymetric and backscatter imaging of the Poverty Bay Indentation across the northern part of the Hikurangi subduction zone provide new insights into the relationship between seafloor morphology and active structures. The swath bathymetry extends from the edge of the continental shelf to the abyssal plain, at depths of between 100 to 3500 metres. The origin of the slope re-entrant is inferred to be related to multiple seamount impacts, and these collisions have initiated numerous large-scale gravitational collapse structures, multiple debris flow and avalanche deposits, which range in down-slope length from a few hundred metres to more than 40 km. The Poverty Bay Indentation has been simultaneously eroded by canyon systems that exhibit many of the features of incised river systems onshore. The swath images are complemented by the availability of excellent high-quality processed multi-channel seismic reflection data, single channel high-resolution 3.5 kHz seismic reflection data, as well as a limited number of core samples. Seismic reflection profiles and seafloor morphology are used to provide three morpho-structural sections. The comparison of these sections highlights the different effects of seamount subduction on the evolution of the margin and the re-entrant. The northern two sections are located to the north side of the re-entrant and reveal the role of seamount impact on the interrelationship between the structural evolution with respect to seafloor morphology. Here the development of an over-steepened margin with fault reactivation, inversion and over- printing leads to very complex structural styles of deformation and geometry in both seismic reflection profiles and seafloor morphology. There is evidence of an older, inactive thrust front buried beneath the upper and mid- slope basins. Beneath the mid-slope a subducted seamount is revealed by the presence of relief on the subduction interface and associated structural complexity in the over-riding wedge. The Poverty Bay canyon represents a structural transition zone coinciding with the re-entrant. The accretionary slope south of the re- entrant conforms more closely to the classic accretionary slope style of deformation. Backthrusts in this section propagate from a much shallower level than in the northern sections. Inversion is commonly observed in the mid slope and continental shelf basins, particularly to the south. Initial interpretations indicate that: i) seamount impact significantly influences the structural evolution, and submarine geomorphology of the inboard slope of the Hikurangi subduction zone, including the generation of large-scale gravitational collapse features; ii) the large gully systems located at the upper shelf slope boundary represent the most likely source areas for the multiple mega debris flows recognised from seafloor morphology and in seismic sections; iii) there exists a complex interaction between the evolving thrust-driven submarine ridges, ponded slope basins and the structural geometry and evolution of the near-surface fault zones (imbrication); iv) the submarine canyons may initiate complex patterns of fault zone segmentation and displacement transfer within the accretionary slope; and v) seamount subduction and subsequent instability of the margin may directly result in tsunami generation.

Variable and complex food web structures revealed by exploring missing trophic links between birds and biofilm.

PubMed

Kuwae, Tomohiro; Miyoshi, Eiichi; Hosokawa, Shinya; Ichimi, Kazuhiko; Hosoya, Jun; Amano, Tatsuya; Moriya, Toshifumi; Kondoh, Michio; Ydenberg, Ronald C; Elner, Robert W

2012-04-01

Food webs are comprised of a network of trophic interactions and are essential to elucidating ecosystem processes and functions. However, the presence of unknown, but critical networks hampers understanding of complex and dynamic food webs in nature. Here, we empirically demonstrate a missing link, both critical and variable, by revealing that direct predator-prey relationships between shorebirds and biofilm are widespread and mediated by multiple ecological and evolutionary determinants. Food source mixing models and energy budget estimates indicate that the strength of the missing linkage is dependent on predator traits (body mass and foraging action rate) and the environment that determines food density. Morphological analyses, showing that smaller bodied species possess more developed feeding apparatus to consume biofilm, suggest that the linkage is also phylogenetically dependent and affords a compelling re-interpretation of niche differentiation. We contend that exploring missing links is a necessity for revealing true network structure and dynamics. © 2012 Blackwell Publishing Ltd/CNRS.

The mushroom family Psathyrellaceae: evidence for large-scale polyphyly of the genus Psathyrella.

PubMed

Padamsee, Mahajabeen; Matheny, P Brandon; Dentinger, Bryn T M; McLaughlin, David J

2008-02-01

Psathyrella is the archetypal little brown mushroom genus with few easily discernable characters causing it to be considered a "clean-up" genus for other small brown-spored saprotrophic species found worldwide. While molecular studies have demonstrated that mushroom genera based on homoplastic morphological characters are artificial, the degree of phylogenetic heterogeneity contained within Psathyrella and Psathyrellaceae has never been appropriately addressed. For this study, 132 ribosomal sequences from approximately one-tenth of the known Psathyrella species worldwide, including representatives of most subgeneric subdivisions, and three closely related coprinoid genera (Parasola, Coprinopsis, Coprinellus) were evaluated using multiple phylogenetic methods, including likelihood, with Agaricaceae as the outgroup. Our results indicated that Psathyrella was polyphyletic. Conservatively, the genus can be separated into 11 clades of which five can be raised to generic status. Most species of Psathyrella, including its type species P. gracilis, formed a large clade with Coprinellus, which appeared to be derived from within Psathyrella. Generic limits of Parasola, Lacrymaria, and Coprinopsis should be reevaluated. Several taxa previously synonymized based on morphological features were phylogenetically distinct. Morphological features traditionally used to subdivide Psathyrella appeared to be mostly convergent (homoplasious) when traced upon the resulting phylogenies, although several had high RI values. These results were interpreted in light of the two major taxonomic treatments of Psathyrella and revealed substantial inconsistencies between the molecular- and morphology-derived inferences of relationships.

Sinuosity of Martian rampart ejecta deposits

NASA Technical Reports Server (NTRS)

Barlow, Nadine G.

1994-01-01

The sinuosities of 2213 Martian rampart ejecta craters are quantified through measurement of the ejecta flow front perimeter and ejecta area. This quantity, called lobateness, was computed for each complete lobe of the 1582 single lobe (SL), 251 double lobe (DL), and 380 multiple lobe (ML) craters included in this study. A lobateness value of 1 indicates a circular ejecta blanket, whereas more sinuous ejecta perimeters have lobateness values greater than 1. Although resolution does have an effect on the absolute values of lobateness, the general relationships between lobateness and morphology exist regardless of resolution. Evaluation of the lobateness values reveals that the outer lobes of DL and ML craters have higher median lobateness values (i.e., are more sinuous) than the inner lobes. The outermost lobe of ML craters displays higher lobateness values than the outer lobe of DL craters or the single lobe of SL craters. Previous reports of lobateness-diameter, lobateness-latitude, and lobateness-terrain relationships for rampart craters are not supported by this study. Many of the differences between the results of this study and the previous lobateness analyses can be attributed to the inclusion of resolution effects and the distinction between different ejecta morphologies in this study. The results of this study taken together with a previous analysis of the distribution and diameter dependence of different ejecta morphologies are most consistent with the theory that Martian lobate ejecta morphologies form from impact into subsurface volatiles.

Phylogenetic estimation and morphological evolution of Arundinarieae (Bambusoideae: Poaceae) based on plastome phylogenomic analysis.

PubMed

Attigala, Lakshmi; Wysocki, William P; Duvall, Melvin R; Clark, Lynn G

2016-08-01

We explored phylogenetic relationships among the twelve lineages of the temperate woody bamboo clade (tribe Arundinarieae) based on plastid genome (plastome) sequence data. A representative sample of 28 taxa was used and maximum parsimony, maximum likelihood and Bayesian inference analyses were conducted to estimate the Arundinarieae phylogeny. All the previously recognized clades of Arundinarieae were supported, with Ampelocalamus calcareus (Clade XI) as sister to the rest of the temperate woody bamboos. Well supported sister relationships between Bergbambos tessellata (Clade I) and Thamnocalamus spathiflorus (Clade VII) and between Kuruna (Clade XII) and Chimonocalmus (Clade III) were revealed by the current study. The plastome topology was tested by taxon removal experiments and alternative hypothesis testing and the results supported the current plastome phylogeny as robust. Neighbor-net analyses showed few phylogenetic signal conflicts, but suggested some potentially complex relationships among these taxa. Analyses of morphological character evolution of rhizomes and reproductive structures revealed that pachymorph rhizomes were most likely the ancestral state in Arundinarieae. In contrast leptomorph rhizomes either evolved once with reversions to the pachymorph condition or multiple times in Arundinarieae. Further, pseudospikelets evolved independently at least twice in the Arundinarieae, but the ancestral state is ambiguous. Copyright © 2016 Elsevier Inc. All rights reserved.

Multiple microscopic approaches demonstrate linkage between chromoplast architecture and carotenoid composition in diverse Capsicum annuum fruit.

PubMed

Kilcrease, James; Collins, Aaron M; Richins, Richard D; Timlin, Jerilyn A; O'Connell, Mary A

2013-12-01

Increased accumulation of specific carotenoids in plastids through plant breeding or genetic engineering requires an understanding of the limitations that storage sites for these compounds may impose on that accumulation. Here, using Capsicum annuum L. fruit, we demonstrate directly the unique sub-organellar accumulation sites of specific carotenoids using live cell hyperspectral confocal Raman microscopy. Further, we show that chromoplasts from specific cultivars vary in shape and size, and these structural variations are associated with carotenoid compositional differences. Live-cell imaging utilizing laser scanning confocal (LSCM) and confocal Raman microscopy, as well as fixed tissue imaging by scanning and transmission electron microscopy (SEM and TEM), all demonstrated morphological differences with high concordance for the measurements across the multiple imaging modalities. These results reveal additional opportunities for genetic controls on fruit color and carotenoid-based phenotypes. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

Mitochondrial phylogenomics of Hemiptera reveals adaptive innovations driving the diversification of true bugs

PubMed Central

Li, Hu; Leavengood, John M.; Chapman, Eric G.; Burkhardt, Daniel; Song, Fan; Jiang, Pei; Liu, Jinpeng; Cai, Wanzhi

2017-01-01

Hemiptera, the largest non-holometabolous order of insects, represents approximately 7% of metazoan diversity. With extraordinary life histories and highly specialized morphological adaptations, hemipterans have exploited diverse habitats and food sources through approximately 300 Myr of evolution. To elucidate the phylogeny and evolutionary history of Hemiptera, we carried out the most comprehensive mitogenomics analysis on the richest taxon sampling to date covering all the suborders and infraorders, including 34 newly sequenced and 94 published mitogenomes. With optimized branch length and sequence heterogeneity, Bayesian analyses using a site-heterogeneous mixture model resolved the higher-level hemipteran phylogeny as (Sternorrhyncha, (Auchenorrhyncha, (Coleorrhyncha, Heteroptera))). Ancestral character state reconstruction and divergence time estimation suggest that the success of true bugs (Heteroptera) is probably due to angiosperm coevolution, but key adaptive innovations (e.g. prognathous mouthpart, predatory behaviour, and haemelytron) facilitated multiple independent shifts among diverse feeding habits and multiple independent colonizations of aquatic habitats. PMID:28878063

Characteristics of a cell line established from a patient with multiple osteosarcoma, appearing 13 years after treatment for bilateral retinoblastoma.

PubMed

Fodstad, O; Brøgger, A; Bruland, O; Solheim, O P; Nesland, J M; Pihl, A

1986-07-15

An osteosarcoma cell line, OHS, was established from a patient with multiple skeletal manifestations of osteosarcoma, developing after bilateral retinoblastoma. The tumor cells expressed sarcoma-associated antigens and showed rapid growth in monolayers and as multicellular spheroids. They formed distinct colonies in soft agar, and subcutaneous tumors in nude mice. Morphological studies indicated that OHS cells had retained important characteristics of the cells of origin. No deletion of the retinoblastoma genes on chromosome 13q14 could be demonstrated with the banding techniques used. However, cytogenetic studies revealed double minute chromosomes, as evidence of gene amplification, as well as translocations involving chromosomes 1,6,11 and 13. The OHS line can be used to study the genetic basis of tumor initiation and growth, and to elucidate factors predisposing for second primary cancers in retinoblastoma patients.

One-step formation of multiple Pickering emulsions stabilized by self-assembled poly(dodecyl acrylate-co-acrylic acid) nanoparticles.

PubMed

Zhu, Ye; Sun, Jianhua; Yi, Chenglin; Wei, Wei; Liu, Xiaoya

2016-09-13

In this study, a one-step generation of stable multiple Pickering emulsions using pH-responsive polymeric nanoparticles as the only emulsifier was reported. The polymeric nanoparticles were self-assembled from an amphiphilic random copolymer poly(dodecyl acrylate-co-acrylic acid) (PDAA), and the effect of the copolymer content on the size and morphology of PDAA nanoparticles was determined by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The emulsification study of PDAA nanoparticles revealed that multiple Pickering emulsions could be generated through a one-step phase inversion process by using PDAA nanoparticles as the stabilizer. Moreover, the emulsification performance of PDAA nanoparticles at different pH values demonstrated that multiple emulsions with long-time stability could only be stabilized by PDAA nanoparticles at pH 5.5, indicating that the surface wettability of PDAA nanoparticles plays a crucial role in determining the type and stability of the prepared Pickering emulsions. Additionally, the polarity of oil does not affect the emulsification performance of PDAA nanoparticles, and a wide range of oils could be used as the oil phase to prepare multiple emulsions. These results demonstrated that multiple Pickering emulsions could be generated via the one-step emulsification process using self-assembled polymeric nanoparticles as the stabilizer, and the prepared multiple emulsions have promising potential to be applied in the cosmetic, medical, and food industries.

Relating hyporheic fluxes, residence times, and redox-sensitive biogeochemical processes upstream of beaver dams

USGS Publications Warehouse

Briggs, Martin A.; Lautz, Laura; Hare, Danielle K.

2013-01-01

¨hler number seemed to overestimate the actual transition as indicated by multiple secondary electron acceptors, illustrating the gradient nature of anaerobic transition. Temporal flux variability in low-flux morphologies generated a much greater range in hyporheic redox conditions compared to high-flux zones, and chemical responses to changing flux rates were consistent with those predicted from the empirical relationship between redox condition and residence time. The Raz tracer revealed that hyporheic flow paths have strong net aerobic respiration, particularly at higher residence time, but this reactive exchange did not affect the net stream signal at the reach scale.

Deep conservation of cis-regulatory elements in metazoans

PubMed Central

Maeso, Ignacio; Irimia, Manuel; Tena, Juan J.; Casares, Fernando; Gómez-Skarmeta, José Luis

2013-01-01

Despite the vast morphological variation observed across phyla, animals share multiple basic developmental processes orchestrated by a common ancestral gene toolkit. These genes interact with each other building complex gene regulatory networks (GRNs), which are encoded in the genome by cis-regulatory elements (CREs) that serve as computational units of the network. Although GRN subcircuits involved in ancient developmental processes are expected to be at least partially conserved, identification of CREs that are conserved across phyla has remained elusive. Here, we review recent studies that revealed such deeply conserved CREs do exist, discuss the difficulties associated with their identification and describe new approaches that will facilitate this search. PMID:24218633

Investigations of the historic textiles excavated from Ancient Ainos (Enez - Turkey) by multiple analytical techniques

NASA Astrophysics Data System (ADS)

Akyuz, Sevim; Akyuz, Tanil; Cakan, Banu; Basaran, Sait

2014-09-01

Some metal ornamented textile specimens and a textile button, excavated from Ancient Ainos (Enez - Turkey), have been investigated using FTIR and EDXRF spectrometry, for the purpose of material identification. FTIR spectral results indicated that textiles were made from partially degummed Bombyx mori silk. The IR spectral investigation of the textile button revealed that some cellulose fillings were used inside the button. The EDXRF analysis of the metal ornaments showed that they were silver plated copper. Surface morphology of the textiles and the metal ornaments were investigated by SEM images. It was shown that textile fibers were highly degraded.

Taxonomy and species boundaries in the coral genus Favia Milne Edwards and Haime, 1857 (Cnidaria: Scleractinia) from Thailand revealed by morphological and genetic data

NASA Astrophysics Data System (ADS)

Kongjandtre, N.; Ridgway, T.; Cook, L. G.; Huelsken, T.; Budd, A. F.; Hoegh-Guldberg, O.

2012-06-01

While Faviidae is a widely and uniformly distributed coral family throughout the Indo-Pacific, the extensive phenotypic plasticity of colony surface and corallite features often confounds the use of macromorphological characters in species identification, and contributes to conflict between traditional classification and molecular analyses of the group. Recent advances in morphological and molecular techniques now provide a suite of methods to re-address coral taxonomy in complex groups, such as that represented by the Faviidae. This study combines morphologic measurements including "3D coordinates landmarks" data with phylogenetic assessments of nuclear (ITS) and mitochondrial (COI-trnM) DNA to assess species boundaries in nine species of Faviidae with para-septothecal walls from Thailand. Strong concordance was found between morphological features and a priori groupings based on both morphospecies and genetically defined groups (ITS and COI-trnM). Favia truncatus was the most well-defined species based on morphological analyses, and it was also shown to be monophyletic using phylogenetic analyses. Besides F. truncatus, the only other species that was found to be monophyletic in analyses of both genes was F. cf. helianthoides, but its skeletal morphology overlapped with the F. favus species complex (comprised of F. favus, F. speciosa, F. matthaii and F. rotumana). Although not genetically monophyletic, the F. favus species complex and F. pallida were fairly well delineated morphologically. Morphospecies within the F. favus species complex are therefore possibly a result of genetic drift and/or stable polymorphisms driven by divergent selection. These results represent a first step toward a taxonomic revision of the Indo-Pacific Favia, which will integrate morphological methods with the study of type material, genetic information, reproductive data, and tests of phenotypic plasticity—given that multiple lines of evidence are needed to resolve ambiguous species and assign species names.

Whole-organ cell shape analysis reveals the developmental basis of ascidian notochord taper.

PubMed

Veeman, Michael T; Smith, William C

2013-01-15

Here we use in toto imaging together with computational segmentation and analysis methods to quantify the shape of every cell at multiple stages in the development of a simple organ: the notochord of the ascidian Ciona savignyi. We find that cell shape in the intercalated notochord depends strongly on anterior-posterior (AP) position, with cells in the middle of the notochord consistently wider than cells at the anterior or posterior. This morphological feature of having a tapered notochord is present in many chordates. We find that ascidian notochord taper involves three main mechanisms: Planar Cell Polarity (PCP) pathway-independent sibling cell volume asymmetries that precede notochord cell intercalation; the developmental timing of intercalation, which proceeds from the anterior and posterior towards the middle; and the differential rates of notochord cell narrowing after intercalation. A quantitative model shows how the morphology of an entire developing organ can be controlled by this small set of cellular mechanisms. Copyright © 2012 Elsevier Inc. All rights reserved.

Enrichment of dynamic chromosomal crosslinks drive phase separation of the nucleolus

PubMed Central

Hult, Caitlin; Adalsteinsson, David; Vasquez, Paula A.; Lawrimore, Josh; Bennett, Maggie; York, Alyssa; Cook, Diana; Yeh, Elaine; Forest, Mark Gregory

2017-01-01

Abstract Regions of highly repetitive DNA, such as those found in the nucleolus, show a self-organization that is marked by spatial segregation and frequent self-interaction. The mechanisms that underlie the sequestration of these sub-domains are largely unknown. Using a stochastic, bead-spring representation of chromatin in budding yeast, we find enrichment of protein-mediated, dynamic chromosomal cross-links recapitulates the segregation, morphology and self-interaction of the nucleolus. Rates and enrichment of dynamic crosslinking have profound consequences on domain morphology. Our model demonstrates the nucleolus is phase separated from other chromatin in the nucleus and predicts that multiple rDNA loci will form a single nucleolus independent of their location within the genome. Fluorescent labeling of budding yeast nucleoli with CDC14-GFP revealed that a split rDNA locus indeed forms a single nucleolus. We propose that nuclear sub-domains, such as the nucleolus, result from phase separations within the nucleus, which are driven by the enrichment of protein-mediated, dynamic chromosomal crosslinks. PMID:28977453

Whole-organ cell shape analysis reveals the developmental basis of ascidian notochord taper

PubMed Central

Veeman, Michael T.; Smith, William C.

2012-01-01

Here we use in toto imaging together with computational segmentation and analysis methods to quantify the shape of every cell at multiple stages in the development of a simple organ: the notochord of the ascidian Ciona savignyi. We find that cell shape in the intercalated notochord depends strongly on anterior-posterior (AP) position, with cells in the middle of the notochord consistently wider than cells at the anterior or posterior. This morphological feature of having a tapered notochord is present in many chordates. We find that ascidian notochord taper involves three main mechanisms: Planar Cell Polarity (PCP) pathway-independent sibling cell volume asymmetries that precede notochord cell intercalation; the developmental timing of intercalation, which proceeds from the anterior and posterior towards the middle; and the differential rates of notochord cell narrowing after intercalation. A quantitative model shows how the morphology of an entire developing organ can be controlled by this small set of cellular mechanisms. PMID:23165294

Characterization of single spore isolates of Agaricus bisporus (Lange) Imbach using conventional and molecular methods.

PubMed

Sharma, Manju; Suman, B C; Gupta, Dharmesh

2014-10-01

Strains A-15, S11, S-140, and U3 of Agaricus bisporus (Lange) Imbach, were used as parent strains for raising single spore homokaryotic isolates. Out of total 1,642 single spore isolates, only 36 single spore isolates were homokaryons and exhibited slow mycelial growth rate (≤2.0 mm/day) and appressed colony morphology. All these SSIs failed to produce pinheads in Petri plates even after 65 days of incubation, whereas the strandy slow growing SSIs along with parent strains were able to form the fructification in petriplates after 30 days. Out of 24, six ISSR primers, exhibited scorable bands. In the ISSR fingerprints, single spore isolates, homokaryons, lacked amplification products at multiple loci; they grow slowly and all of them had appressed types of colony morphology. The study revealed losses of ISSR polymorphic patterns in non-fertile homokaryotic single spore isolates compared to the parental control or fertile heterokaryotic single spore isolates.

Patterns of specificity and diversity in species of Paraorygmatobothrium Ruhnke, 1994 (Cestoda: Phyllobothriidae) in Moreton Bay, Queensland, Australia, with the description of four new species.

PubMed

Cutmore, Scott C; Bennett, Michael B; Miller, Terrence L; Cribb, Thomas H

2017-11-01

A survey of tapeworms of galeomorph sharks from Moreton Bay (Queensland, Australia) identified a complex of species of Paraorygmatobothrium Ruhnke, 1994 infecting 11 carcharhiniform and two orectolobiform species. Combined morphological and multi-locus molecular analyses (based on the 28S nuclear ribosomal RNA and partial mitochondrial NADH dehydrogenase subunit 1 genes) revealed the presence of 12 species of Paraorygmatobothrium; four species (Paraorygmatobothrium christopheri n. sp., P. harti n. sp., P. sinclairtaylori n. sp. and P. ullmanni n. sp.) are considered to be new to science and are formally described, four represent known species, and four lack sufficient morphological data to allow definitive identification. In contrast to previous records for the genus, four of the species found in this study exhibited low host specificity [P. orectolobi (Butler, 1987) Ruhnke, 2011, P. sinclairtaylori, P. ullmanni and Paraorygmatobothrium sp. 3], three stenoxenic species were each found in two closely-related sharks (P. orectolobi, P. ullmanni and Paraorygmatobothrium sp. 3) and one euryxenic species was found in five species from two shark families (P. sinclairtaylori). One species was found to exhibit mild morphologically plasticity (P. orectolobi), with size range being associated with different shark species. Conversely, collections of almost morphologically indistinguishable specimens from single shark species were found to represent multiple species of Paraorygmatobothrium. The findings of this study indicate that the description of species of this genus on the basis of morphological data alone is problematic and that the inclusion of multi-locus molecular data is essential for future work on Paraorygmatobothrium. Host specificity, morphology and phylogenetic relatedness of species of Paraorygmatobothrium are explored.

Comparative assessment of genetic and morphological variation at an extensive hybrid zone between two wild cats in southern Brazil.

PubMed

Trigo, Tatiane C; Tirelli, Flávia P; de Freitas, Thales R O; Eizirik, Eduardo

2014-01-01

Increased attention towards the Neotropical cats Leopardus guttulus and L. geoffroyi was prompted after genetic studies identified the occurrence of extensive hybridization between them at their geographic contact zone in southern Brazil. This is a region where two biomes intersect, each of which is associated with one of the hybridizing species (Atlantic Forest with L. guttulus and Pampas with L. geoffroyi). In this study, we conducted in-depth analyses of multiple molecular markers aiming to characterize the magnitude and spatial structure of this hybrid zone. We also performed a morphological assessment of these species, aiming to test their phenotypic differentiation at the contact zone, as well as the correlation between morphological features and the admixture status of the individuals. We found strong evidence for extensive and complex hybridization, with at least 40% of the individuals sampled in Rio Grande do Sul state (southernmost Brazil) identified as hybrids resulting from post-F1 generations. Despite such a high level of hybridization, samples collected in this state still comprised two recognizable clusters (genetically and morphologically). Genetically pure individuals were sampled mainly in regions farther from the contact zone, while hybrids concentrated in a central region (exactly at the interface between the two biomes). The morphological data set also revealed a strong spatial structure, which was correlated with the molecular results but displayed an even more marked separation between the clusters. Hybrids often did not present intermediate body sizes and could not be clearly distinguished morphologically from the parental forms. This observation suggests that some selective pressure may be acting on the hybrids, limiting their dispersal away from the hybrid zone and perhaps favoring genomic combinations that maintain adaptive phenotypic features of one or the other parental species.

Comparative Assessment of Genetic and Morphological Variation at an Extensive Hybrid Zone between Two Wild Cats in Southern Brazil

PubMed Central

Trigo, Tatiane C.; Tirelli, Flávia P.; de Freitas, Thales R. O.; Eizirik, Eduardo

2014-01-01

Increased attention towards the Neotropical cats Leopardus guttulus and L. geoffroyi was prompted after genetic studies identified the occurrence of extensive hybridization between them at their geographic contact zone in southern Brazil. This is a region where two biomes intersect, each of which is associated with one of the hybridizing species (Atlantic Forest with L. guttulus and Pampas with L. geoffroyi). In this study, we conducted in-depth analyses of multiple molecular markers aiming to characterize the magnitude and spatial structure of this hybrid zone. We also performed a morphological assessment of these species, aiming to test their phenotypic differentiation at the contact zone, as well as the correlation between morphological features and the admixture status of the individuals. We found strong evidence for extensive and complex hybridization, with at least 40% of the individuals sampled in Rio Grande do Sul state (southernmost Brazil) identified as hybrids resulting from post-F1 generations. Despite such a high level of hybridization, samples collected in this state still comprised two recognizable clusters (genetically and morphologically). Genetically pure individuals were sampled mainly in regions farther from the contact zone, while hybrids concentrated in a central region (exactly at the interface between the two biomes). The morphological data set also revealed a strong spatial structure, which was correlated with the molecular results but displayed an even more marked separation between the clusters. Hybrids often did not present intermediate body sizes and could not be clearly distinguished morphologically from the parental forms. This observation suggests that some selective pressure may be acting on the hybrids, limiting their dispersal away from the hybrid zone and perhaps favoring genomic combinations that maintain adaptive phenotypic features of one or the other parental species. PMID:25250657

Multiple roles of filopodial dynamics in particle capture and phagocytosis and phenotypes of Cdc42 and Myo10 deletion

PubMed Central

Horsthemke, Markus; Bachg, Anne C.; Groll, Katharina; Moyzio, Sven; Müther, Barbara; Hemkemeyer, Sandra A.; Wedlich-Söldner, Roland; Sixt, Michael; Tacke, Sebastian; Bähler, Martin; Hanley, Peter J.

2017-01-01

Macrophage filopodia, finger-like membrane protrusions, were first implicated in phagocytosis more than 100 years ago, but little is still known about the involvement of these actin-dependent structures in particle clearance. Using spinning disk confocal microscopy to image filopodial dynamics in mouse resident Lifeact-EGFP macrophages, we show that filopodia, or filopodia-like structures, support pathogen clearance by multiple means. Filopodia supported the phagocytic uptake of bacterial (Escherichia coli) particles by (i) capturing along the filopodial shaft and surfing toward the cell body, the most common mode of capture; (ii) capturing via the tip followed by retraction; (iii) combinations of surfing and retraction; or (iv) sweeping actions. In addition, filopodia supported the uptake of zymosan (Saccharomyces cerevisiae) particles by (i) providing fixation, (ii) capturing at the tip and filopodia-guided actin anterograde flow with phagocytic cup formation, and (iii) the rapid growth of new protrusions. To explore the role of filopodia-inducing Cdc42, we generated myeloid-restricted Cdc42 knock-out mice. Cdc42-deficient macrophages exhibited rapid phagocytic cup kinetics, but reduced particle clearance, which could be explained by the marked rounded-up morphology of these cells. Macrophages lacking Myo10, thought to act downstream of Cdc42, had normal morphology, motility, and phagocytic cup formation, but displayed markedly reduced filopodia formation. In conclusion, live-cell imaging revealed multiple mechanisms involving macrophage filopodia in particle capture and engulfment. Cdc42 is not critical for filopodia or phagocytic cup formation, but plays a key role in driving macrophage lamellipodial spreading. PMID:28289096

Quadriplegic areflexic ICU illness: selective thick filament loss and normal nerve histology.

PubMed

Sander, Howard W; Golden, Marianna; Danon, Moris J

2002-10-01

Areflexic quadriplegia that occurs in the intensive care unit (ICU) is commonly ascribed to critical illness polyneuropathy based upon electrophysiology or muscle light microscopy. However, electron microscopy often documents a selective thick filament loss myopathy. Eight ICU patients who developed areflexic quadriplegia underwent biopsy. Seven patients had received steroids, and 2 had also received paralytic agents. Electrodiagnostic studies revealed absent or low-amplitude motor responses in 7. Sensory responses were normal in 5 of 6 and absent in 1. Initial electromyography revealed absent (n = 3), small (n = 3), or polyphasic (n = 1) motor unit potentials, and diffuse fibrillation potentials (n = 5). In all 8, light microscopy of muscle revealed numerous atrophic-angulated fibers and corelike lesions, and electron microscopy revealed extensive thick filament loss. Morphology of sural and intramuscular nerves, and, in one autopsied case, of the obturator nerve and multiple nerve roots, was normal. Although clinical, electrodiagnostic, and light microscopic features mimicked denervating disease, muscle electron microscopy revealed thick filament loss, and nerve histology was normal. This suggests that areflexic ICU quadriplegia is a primary myopathy and not an axonal polyneuropathy. Copyright 2002 Wiley Periodicals, Inc. Muscle Nerve 26: 499-505, 2002

Theory of multiple quantum dot formation in strained-layer heteroepitaxy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Du, Lin; Maroudas, Dimitrios, E-mail: maroudas@ecs.umass.edu

2016-07-11

We develop a theory for the experimentally observed formation of multiple quantum dots (QDs) in strained-layer heteroepitaxy based on surface morphological stability analysis of a coherently strained epitaxial thin film on a crystalline substrate. Using a fully nonlinear model of surface morphological evolution that accounts for a wetting potential contribution to the epitaxial film's free energy as well as surface diffusional anisotropy, we demonstrate the formation of multiple QD patterns in self-consistent dynamical simulations of the evolution of the epitaxial film surface perturbed from its planar state. The simulation predictions are supported by weakly nonlinear analysis of the epitaxial filmmore » surface morphological stability. We find that, in addition to the Stranski-Krastanow instability, long-wavelength perturbations from the planar film surface morphology can trigger a nonlinear instability, resulting in the splitting of a single QD into multiple QDs of smaller sizes, and predict the critical wavelength of the film surface perturbation for the onset of the nonlinear tip-splitting instability. The theory provides a fundamental interpretation for the observations of “QD pairs” or “double QDs” and other multiple QDs reported in experimental studies of epitaxial growth of semiconductor strained layers and sets the stage for precise engineering of tunable-size nanoscale surface features in strained-layer heteroepitaxy by exploiting film surface nonlinear, pattern forming phenomena.« less

Monitoring the Attack Incidences and Damage Caused by the Almond Bark Beetle, Scolytus amygdali, in Almond Orchards

PubMed Central

Cuthbertson, Andrew G. S.; Braham, Mohamed

2018-01-01

The almond bark beetle, Scolytus amygdali Geurin-Meneville, is responsible for significant loss of fruit production in almond orchards throughout the world. Here, we studied the damage and the incidences of S. amygdali attack on two different scales: (1) at the level of a single tree; and (2) in an entire orchard. Our results revealed no differences in attack level among four orientations (east, west, south and north sides) for the whole tree. However, the bark that was facing west side in the direction of the prevailing wind was found to be the most suitable for females to initiate attack in Stratum S2. Attack distribution remains the same among different strata (strata is vertical divisions of the tree from the ground to the uppermost twigs with ~40 cm intervals). More than 50% of attack was observed in the trunk of the tree and upper strata. However, multiplication rate (number of emerged adults/maternal gallery) varies significantly between strata. In addition, we studied attack intensity (holes produced by beetle per tree) comparing it to tree morphology (flowers, leaves and circumferences) and gum deposit. Our results revealed a positive correlation between attack intensity and gum deposits, and a negative correlation between attack intensity and tree morphology. This revealed that gum on the tree was an indicator for attack intensity. A positive correlation between attack intensity and the circumference of the tree revealed that older trees were more susceptible to S. amygdali attack. These results, while preliminary, aim to help in the monitoring of S. amygdali populations before deciding to apply any control measures. PMID:29301271

Individual Morphological Brain Network Construction Based on Multivariate Euclidean Distances Between Brain Regions.

PubMed

Yu, Kaixin; Wang, Xuetong; Li, Qiongling; Zhang, Xiaohui; Li, Xinwei; Li, Shuyu

2018-01-01

Morphological brain network plays a key role in investigating abnormalities in neurological diseases such as mild cognitive impairment (MCI) and Alzheimer's disease (AD). However, most of the morphological brain network construction methods only considered a single morphological feature. Each type of morphological feature has specific neurological and genetic underpinnings. A combination of morphological features has been proven to have better diagnostic performance compared with a single feature, which suggests that an individual morphological brain network based on multiple morphological features would be beneficial in disease diagnosis. Here, we proposed a novel method to construct individual morphological brain networks for two datasets by calculating the exponential function of multivariate Euclidean distance as the evaluation of similarity between two regions. The first dataset included 24 healthy subjects who were scanned twice within a 3-month period. The topological properties of these brain networks were analyzed and compared with previous studies that used different methods and modalities. Small world property was observed in all of the subjects, and the high reproducibility indicated the robustness of our method. The second dataset included 170 patients with MCI (86 stable MCI and 84 progressive MCI cases) and 169 normal controls (NC). The edge features extracted from the individual morphological brain networks were used to distinguish MCI from NC and separate MCI subgroups (progressive vs. stable) through the support vector machine in order to validate our method. The results showed that our method achieved an accuracy of 79.65% (MCI vs. NC) and 70.59% (stable MCI vs. progressive MCI) in a one-dimension situation. In a multiple-dimension situation, our method improved the classification performance with an accuracy of 80.53% (MCI vs. NC) and 77.06% (stable MCI vs. progressive MCI) compared with the method using a single feature. The results indicated that our method could effectively construct an individual morphological brain network based on multiple morphological features and could accurately discriminate MCI from NC and stable MCI from progressive MCI, and may provide a valuable tool for the investigation of individual morphological brain networks.

Linking offshore morphology and interplate kinematics along the Chilean subduction margin

NASA Astrophysics Data System (ADS)

Urrutia, I.; Oncken, O.; Moreno, M.; Cesca, S.

2016-12-01

The coastal morphology along subduction zones is understood to result from the interaction of the megathrust seismic cycle deformation with erosion and sedimentation. The variation of this interplay creates some areas that remain stable and other areas that accumulate permanent deformation over long time scales. However, the link between plate interface kinematics and geomorphology has not been fully explored and therefore a potentially valuable constraint on the long-term seismotectonic segmentation has been neglected. Here, by combining morphometric and statistic analysis with numerical modeling of the transient kinematics (constrained by GPS data along the Chilean margin), we validate that the morphological domains exhibiting conditional stability spatially correlate with locked areas and the rupture extents of recent great earthquakes, and that these domains are primarily related to forearc basins and marine terraces. This correlation, that likely integrates over a time window of several 103 to several 105 years, corroborates that earthquake cycle deformation has a strong imprint on the coastal morphology and that the instrumentally inferred locking has a long term memory across multiple seismic cycles. From this interrelationship we suggest that areas with gentle slopes and that have been identified geodetically as being locked indicate a quiescence process, which can be interpreted as the expression of spatial variations in friction that control the sizes and recurrence intervals of megathrust earthquakes. Our findings reveal that the width of the seismogenic zone is linked to both long and short-term deformations, opening up new avenues for inferring seismic scenarios of a margin by analysing its morphological domains.

The myeloproliferative neoplasms, unclassifiable: clinical and pathological considerations.

PubMed

Gianelli, Umberto; Cattaneo, Daniele; Bossi, Anna; Cortinovis, Ivan; Boiocchi, Leonardo; Liu, Yen-Chun; Augello, Claudia; Bonometti, Arturo; Fiori, Stefano; Orofino, Nicola; Guidotti, Francesca; Orazi, Attilio; Iurlo, Alessandra

2017-02-01

In this study, we investigate in detail the morphological, clinical and molecular features of 71 consecutive patients with a diagnosis of myeloproliferative neoplasms, unclassifiable. We performed a meticulous morphological analysis and found that most of the cases displayed a hypercellular bone marrow (70%) with normal erythropoiesis without left-shifting (59%), increased granulopoiesis with left-shifting (73%) and increased megakaryocytes with loose clustering (96%). Megakaryocytes displayed frequent giant forms with hyperlobulated or bulbous nuclei and/or other maturation defects. Interestingly, more than half of the cases displayed severe bone marrow fibrosis (59%). Median values of hemoglobin level and white blood cells count were all within the normal range; in contrast, median platelets count and lactate dehydrogenase were increased. Little less than half of the patients (44%) showed splenomegaly. JAK2V617F mutation was detected in 72% of all patients. Among the JAK2-negative cases, MPLW515L mutation was found in 17% and CALR mutations in 67% of the investigated cases, respectively. Finally, by multiple correspondence analysis of the morphological profiles, we found that all but four of the cases could be grouped in three morphological clusters with some features similar to those of the classic BCR-ABL1-negative myeloproliferative neoplasms. Analysis of the clinical parameters in these three clusters revealed discrepancies with the morphological profile in about 55% of the patients. In conclusion, we found that the category of myeloproliferative neoplasm, unclassifiable is heterogeneous but identification of different subgroups is possible and should be recommended for a better management of these patients.

Integrative taxonomy of root-knot nematodes reveals multiple independent origins of mitotic parthenogenesis

PubMed Central

Janssen, Toon; Karssen, Gerrit; Topalović, Olivera; Coyne, Danny; Bert, Wim

2017-01-01

During sampling of several Coffea arabica plantations in Tanzania severe root galling, caused by a root-knot nematode was observed. From pure cultures, morphology and morphometrics of juveniles and females matched perfectly with Meloidogyne africana, whereas morphology of the males matched identically with those of Meloidogyne decalineata. Based on their Cox1 sequence, however, the recovered juveniles, females and males were confirmed to belong to the same species, creating a taxonomic conundrum. Adding further to this puzzle, re-examination of M. oteifae type material showed insufficient morphological evidence to maintain its status as a separate species. Consequently, M. decalineata and M. oteifae are synonymized with M. africana, which is herewith redescribed based on results of light and scanning electron microscopy, ribosomal and mitochondrial DNA sequences, isozyme electrophoresis, along with bionomic and cytogenetic features. Multi-gene phylogenetic analysis placed M. africana outside of the three major clades, together with M. coffeicola, M. ichinohei and M. camelliae. This phylogenetic position was confirmed by several morphological features, including cellular structure of the spermatheca, egg mass position, perineal pattern and head shape. Moreover, M. africana was found to be a polyphagous species, demonstrating that “early-branching” Meloidogyne spp. are not as oligophagous as had previously been assumed. Cytogenetic information indicates M. africana (2n = 21) and M. ardenensis (2n = 51–54) to be a triploid mitotic parthenogenetic species, revealing at least four independent origins of mitotic parthenogenesis within the genus Meloidogyne. Furthermore, M. mali (n = 12) was found to reproduce by amphimixis, indicating that amphimictic species with a limited number of chromosomes are widespread in the genus, potentially reflecting the ancestral state of the genus. The wide variation in chromosome numbers and associated changes in reproduction modes indicate that cytogenetic evolution played a crucial role in the speciation of root-knot nematodes and plant-parasitic nematodes in general. PMID:28257464

Complete volumetric decomposition of individual trabecular plates and rods and its morphological correlations with anisotropic elastic moduli in human trabecular bone.

PubMed

Liu, X Sherry; Sajda, Paul; Saha, Punam K; Wehrli, Felix W; Bevill, Grant; Keaveny, Tony M; Guo, X Edward

2008-02-01

Trabecular plates and rods are important microarchitectural features in determining mechanical properties of trabecular bone. A complete volumetric decomposition of individual trabecular plates and rods was used to assess the orientation and morphology of 71 human trabecular bone samples. The ITS-based morphological analyses better characterize microarchitecture and help predict anisotropic mechanical properties of trabecular bone. Standard morphological analyses of trabecular architecture lack explicit segmentations of individual trabecular plates and rods. In this study, a complete volumetric decomposition technique was developed to segment trabecular bone microstructure into individual plates and rods. Contributions of trabecular type-associated morphological parameters to the anisotropic elastic moduli of trabecular bone were studied. Seventy-one human trabecular bone samples from the femoral neck (FN), tibia, and vertebral body (VB) were imaged using muCT or serial milling. Complete volumetric decomposition was applied to segment trabecular bone microstructure into individual plates and rods. The orientation of each individual trabecula was determined, and the axial bone volume fractions (aBV/TV), axially aligned bone volume fraction along each orthotropic axis, were correlated with the elastic moduli. The microstructural type-associated morphological parameters were derived and compared with standard morphological parameters. Their contributions to the anisotropic elastic moduli, calculated by finite element analysis (FEA), were evaluated and compared. The distribution of trabecular orientation suggested that longitudinal plates and transverse rods dominate at all three anatomic sites. aBV/TV along each axis, in general, showed a better correlation with the axial elastic modulus (r(2) = 0.95 approximately 0.99) compared with BV/TV (r(2) = 0.93 approximately 0.94). The plate-associated morphological parameters generally showed higher correlations with the corresponding standard morphological parameters than the rod-associated parameters. Multiple linear regression models of six elastic moduli with individual trabeculae segmentation (ITS)-based morphological parameters (adjusted r(2) = 0.95 approximately 0.98) performed equally well as those with standard morphological parameters (adjusted r(2) = 0.94 approximately 0.97) but revealed specific contributions from individual trabecular plates or rods. The ITS-based morphological analyses provide a better characterization of the morphology and trabecular orientation of trabecular bone. The axial loading of trabecular bone is mainly sustained by the axially aligned trabecular bone volume. Results suggest that trabecular plates dominate the overall elastic properties of trabecular bone.

How does a planet excite multiple spiral arms?

NASA Astrophysics Data System (ADS)

Bae, Jaehan; Zhu, Zhaohuan

2018-01-01

Protoplanetary disk simulations show that a single planet excites multiple spiral arms in the background disk, potentially supported by the multi-armed spirals revealed with recent high-resolution observations in some disks. The existence of multiple spiral arms is of importance in many aspects. It is empirically found that the arm-to-arm separation increases as a function of the planetary mass, so one can use the morphology of observed spiral arms to infer the mass of unseen planets. In addition, a spiral arm opens a radial gap as it steepens into a shock, so when a planet excites multiple spiral arms it can open multiple gaps in the disk. Despite the important implications, however, the formation mechanism of multiple spiral arms has not been fully understood by far.In this talk, we explain how a planet excites multiple spiral arms. The gravitational potential of a planet can be decomposed into a Fourier series, a sum of individual azimuthal modes having different azimuthal wavenumbers. Using a linear wave theory, we first demonstrate that appropriate sets of Fourier decomposed waves can be in phase, raising a possibility that constructive interference among the waves can produce coherent structures - spiral arms. More than one spiral arm can form since such constructive interference can occur at different positions in the disk for different sets of waves. We then verify this hypothesis using a suite of two-dimensional hydrodynamic simulations. Finally, we present non-linear behavior in the formation of multiple spiral arms.

Nuclear markers reveal that inter-lake cichlids' similar morphologies do not reflect similar genealogy.

PubMed

Kassam, Daud; Seki, Shingo; Horic, Michio; Yamaoka, Kosaku

2006-08-01

The apparent inter-lake morphological similarity among East African Great Lakes' cichlid species/genera has left evolutionary biologists asking whether such similarity is due to sharing of common ancestor or mere convergent evolution. In order to answer such question, we first used Geometric Morphometrics, GM, to quantify morphological similarity and then subsequently used Amplified Fragment Length Polymorphism, AFLP, to determine if similar morphologies imply shared ancestry or convergent evolution. GM revealed that not all presumed morphological similar pairs were indeed similar, and the dendrogram generated from AFLP data indicated distinct clusters corresponding to each lake and not inter-lake morphological similar pairs. Such results imply that the morphological similarity is due to convergent evolution and not shared ancestry. The congruency of GM and AFLP generated dendrograms imply that GM is capable of picking up phylogenetic signal, and thus GM can be potential tool in phylogenetic systematics.

A Recipe for Soft Fluidic Elastomer Robots

PubMed Central

Marchese, Andrew D.; Katzschmann, Robert K.

2015-01-01

Abstract This work provides approaches to designing and fabricating soft fluidic elastomer robots. That is, three viable actuator morphologies composed entirely from soft silicone rubber are explored, and these morphologies are differentiated by their internal channel structure, namely, ribbed, cylindrical, and pleated. Additionally, three distinct casting-based fabrication processes are explored: lamination-based casting, retractable-pin-based casting, and lost-wax-based casting. Furthermore, two ways of fabricating a multiple DOF robot are explored: casting the complete robot as a whole and casting single degree of freedom (DOF) segments with subsequent concatenation. We experimentally validate each soft actuator morphology and fabrication process by creating multiple physical soft robot prototypes. PMID:27625913

A Recipe for Soft Fluidic Elastomer Robots.

PubMed

Marchese, Andrew D; Katzschmann, Robert K; Rus, Daniela

2015-03-01

This work provides approaches to designing and fabricating soft fluidic elastomer robots. That is, three viable actuator morphologies composed entirely from soft silicone rubber are explored, and these morphologies are differentiated by their internal channel structure, namely, ribbed, cylindrical, and pleated. Additionally, three distinct casting-based fabrication processes are explored: lamination-based casting, retractable-pin-based casting, and lost-wax-based casting. Furthermore, two ways of fabricating a multiple DOF robot are explored: casting the complete robot as a whole and casting single degree of freedom (DOF) segments with subsequent concatenation. We experimentally validate each soft actuator morphology and fabrication process by creating multiple physical soft robot prototypes.

Subduction-Related Structure in the Mw 9.2, 1964 Megathrust Rupture Area Offshore Kodiak Island, Alaska

NASA Astrophysics Data System (ADS)

Krabbenhoeft, A.; von Huene, R.; Klaeschen, D.; Miller, J. J.

2016-12-01

Some of the largest earthquakes worldwide, including the 1964 9.2 Mw megathrust earthquake, occurred in Alaskan subduction zones. To better understand rupture processes and their mechanisms, we relate seafloor morphology from multibeam and regional bathymetric compilations with sub-seafloor images and seismic P-wave velocity structures. We re-processed legacy multichannel seismic (MCS) data including shot- and intra-shotgather interpolation, multiple removal and Kirchhoff depth migration. These images even reveal the shallow structure of the subducting oceanic crust. Traveltime tomography of a coincident vintage (1994) wide angle dataset reveals the P-wave velocity distribution as well as the deep structure of the subducting plate to the ocean crust Moho. The subducting oceanic crust morphology is rough and partly hidden by a thick sediment cover that reaches 3 km depth at the trench axis. Bathymetry shows two major contrasting upper plate morphologies: the shallow dipping lower slope consists of trench-parallel ridges that form the accreted prism whereas the steep rough middle and upper slopes are composed of competent older rock.Thrust faults are distributed across the entire slope, some of which connect with the subducted plate interface. A subtle change in seafloor gradient from the lower to the middle slope coincides with a thrust fault zone marking the boundary between the margin framework and the frontal prism. It corresponds to the most prominent lateral increase in seismic P-wave velocities, 25 km landward of the trench axis.Major thrusts in several MCS-lines are correlated with bathymetric data, showing their > 100 km lateral extent, which might also be tsunamigenic paths of earthquake rupture from the seismogenic zone to the seafloor.

Three routes to crypsis: Stasis, convergence, and parallelism in the Mastigias species complex (Scyphozoa, Rhizostomeae).

PubMed

Swift, H F; Gómez Daglio, L; Dawson, M N

2016-06-01

Evolutionary inference can be complicated by morphological crypsis, particularly in open marine systems that may rapidly dissipate signals of evolutionary processes. These complications may be alleviated by studying systems with simpler histories and clearer boundaries, such as marine lakes-small bodies of seawater entirely surrounded by land. As an example, we consider the jellyfish Mastigias spp. which occurs in two ecotypes, one in marine lakes and one in coastal oceanic habitats, throughout the Indo-West Pacific (IWP). We tested three evolutionary hypotheses to explain the current distribution of the ecotypes: (H1) the ecotypes originated from an ancient divergence; (H2) the lake ecotype was derived recently from the ocean ecotype during a single divergence event; and (H3) the lake ecotype was derived from multiple, recent, independent, divergences. We collected specimens from 21 locations throughout the IWP, reconstructed multilocus phylogenetic and intraspecific relationships, and measured variation in up to 40 morphological characters. The species tree reveals three reciprocally monophyletic regional clades, two of which contain ocean and lake ecotypes, suggesting repeated, independent evolution of coastal ancestors into marine lake ecotypes, consistent with H3; hypothesis testing and an intraspecific haplotype network analysis of samples from Palau reaffirms this result. Phylogenetic character mapping strongly correlates morphology to environment rather than lineage (r=0.7512, p<0.00001). Considering also the deeper relationships among regional clades, morphological similarity in Mastigias spp. clearly results from three separate patterns of evolution: morphological stasis in ocean medusae, convergence of lake morphology across distinct species and parallelism between lake morphologies within species. That three evolutionary routes each result in crypsis illustrates the challenges of interpreting evolutionary processes from patterns of biogeography and diversity in the seas. Identifying cryptic species is only the first step in understanding these processes; an equally important second step is exploring and understanding the processes and patterns that create crypsis. Copyright © 2016 Elsevier Inc. All rights reserved.

Phenotype classification of single cells using SRS microscopy, RNA sequencing, and microfluidics (Conference Presentation)

NASA Astrophysics Data System (ADS)

Streets, Aaron M.; Cao, Chen; Zhang, Xiannian; Huang, Yanyi

2016-03-01

Phenotype classification of single cells reveals biological variation that is masked in ensemble measurement. This heterogeneity is found in gene and protein expression as well as in cell morphology. Many techniques are available to probe phenotypic heterogeneity at the single cell level, for example quantitative imaging and single-cell RNA sequencing, but it is difficult to perform multiple assays on the same single cell. In order to directly track correlation between morphology and gene expression at the single cell level, we developed a microfluidic platform for quantitative coherent Raman imaging and immediate RNA sequencing (RNA-Seq) of single cells. With this device we actively sort and trap cells for analysis with stimulated Raman scattering microscopy (SRS). The cells are then processed in parallel pipelines for lysis, and preparation of cDNA for high-throughput transcriptome sequencing. SRS microscopy offers three-dimensional imaging with chemical specificity for quantitative analysis of protein and lipid distribution in single cells. Meanwhile, the microfluidic platform facilitates single-cell manipulation, minimizes contamination, and furthermore, provides improved RNA-Seq detection sensitivity and measurement precision, which is necessary for differentiating biological variability from technical noise. By combining coherent Raman microscopy with RNA sequencing, we can better understand the relationship between cellular morphology and gene expression at the single-cell level.

Origin of the hungry caterpillar: Evolution of fasting in slug moths (Insecta: Lepidoptera: Limacodidae).

PubMed

Zaspel, J M; Weller, S J; Epstein, M E

2016-01-01

Studies of caterpillar defense strategy evolution typically focus on aposematic coloration, gregarious behavior, and/or chemical defense. In the slug moth family Limacodidae, the evolution of chemical defense is coupled to the life history trait of first instar feeding behaviors. In nettle caterpillars, the first instars fast and molt into a second instar that feeds. In contrast, gelatines and monkey slug larval forms feed in the first instar. This study focused on whether the evolution of fasting associated with the nettle morphology was a derived trait of single or multiple origins. Twenty-nine species of Limacodidae (including one Chrysopolominae) representing 27 genera and four outgroup species with known first and final instar morphologies and behaviors were included. Four out-group species representing Megalopygidae (1 sp), Dalceridae (1 sp) and Aididae (2 sp) were included. These were sequenced for three molecular markers for a total of 4073 bp, mitochondrial COI (∼1500 bp), 18S (∼1900 bp) and the D2 region of 28S (approximately 670 bp). Maximum likelihood and Bayesian analyses were conducted. The resulting phylogeny and comparative analysis of feeding strategy revealed that the nettle caterpillar morphology and behavior of larval fasting may have a single origin. Copyright © 2015 Elsevier Inc. All rights reserved.

Many Specialists for Suppressing Cortical Excitation

PubMed Central

Burkhalter, Andreas

2008-01-01

Cortical computations are critically dependent on GABA-releasing neurons for dynamically balancing excitation with inhibition that is proportional to the overall level of activity. Although it is widely accepted that there are multiple types of interneurons, defining their identities based on qualitative descriptions of morphological, molecular and physiological features has failed to produce a universally accepted ‘parts list’, which is needed to understand the roles that interneurons play in cortical processing. A list of features has been published by the Petilla Interneurons Nomenclature Group, which represents an important step toward an unbiased classification of interneurons. To this end some essential features have recently been studied quantitatively and their association was examined using multidimensional cluster analyses. These studies revealed at least 3 distinct electrophysiological, 6 morphological and 15 molecular phenotypes. This is a conservative estimate of the number of interneuron types, which almost certainly will be revised as more quantitative studies will be performed and similarities will be defined objectively. It is clear that interneurons are organized with physiological attributes representing the most general, molecular characteristics the most detailed and morphological features occupying the middle ground. By themselves, none of these features are sufficient to define classes of interneurons. The challenge will be to determine which features belong together and how cell type-specific feature combinations are genetically specified. PMID:19225588

How discordant morphological and molecular evolution among microorganisms can revise our notions of biodiversity on earth

PubMed Central

Lahr, Daniel J. G.; Laughinghouse, H. Dail; Oliverio, Angela; Gao, Feng; Katz, Laura A.

2014-01-01

Microscopy has revealed a tremendous diversity of bacterial and eukaryotic forms. More recent molecular analyses show discordance in estimates of biodiversity based on morphological analyses. Moreover, phylogenetic analyses of the diversity of microbial forms have revealed evidence of convergence at scales as large as interdomain – i.e. convergent forms shared between bacteria and eukaryotes. Here, we highlight examples of such discordance, focusing on exemplary lineages such as testate amoebae, ciliates and cyanobacteria, which have long histories of morphological study. We discuss examples in two categories: 1) morphologically identical (or highly similar) individuals that are genetically distinct and 2) morphologically distinct individuals that are genetically distinct. We argue that hypotheses about discordance can be tested using the concept of neutral morphologies, or more broadly neutral phenotypes, as a null hypothesis. PMID:25156897

Dynamic Cytology and Transcriptional Regulation of Rice Lamina Joint Development1[OPEN

PubMed Central

2017-01-01

Rice (Oryza sativa) leaf angle is determined by lamina joint and is an important agricultural trait determining leaf erectness and, hence, the photosynthesis efficiency and grain yield. Genetic studies reveal a complex regulatory network of lamina joint development; however, the morphological changes, cytological transitions, and underlying transcriptional programming remain to be elucidated. A systemic morphological and cytological study reveals a dynamic developmental process and suggests a common but distinct regulation of the lamina joint. Successive and sequential cell division and expansion, cell wall thickening, and programmed cell death at the adaxial or abaxial sides form the cytological basis of the lamina joint, and the increased leaf angle results from the asymmetric cell proliferation and elongation. Analysis of the gene expression profiles at four distinct developmental stages ranging from initiation to senescence showed that genes related to cell division and growth, hormone synthesis and signaling, transcription (transcription factors), and protein phosphorylation (protein kinases) exhibit distinct spatiotemporal patterns during lamina joint development. Phytohormones play crucial roles by promoting cell differentiation and growth at early stages or regulating the maturation and senescence at later stages, which is consistent with the quantitative analysis of hormones at different stages. Further comparison with the gene expression profile of leaf inclination1, a mutant with decreased auxin and increased leaf angle, indicates the coordinated effects of hormones in regulating lamina joint. These results reveal a dynamic cytology of rice lamina joint that is fine-regulated by multiple factors, providing informative clues for illustrating the regulatory mechanisms of leaf angle and plant architecture. PMID:28500269

Dynamic Cytology and Transcriptional Regulation of Rice Lamina Joint Development.

PubMed

Zhou, Li-Juan; Xiao, Lang-Tao; Xue, Hong-Wei

2017-07-01

Rice ( Oryza sativa ) leaf angle is determined by lamina joint and is an important agricultural trait determining leaf erectness and, hence, the photosynthesis efficiency and grain yield. Genetic studies reveal a complex regulatory network of lamina joint development; however, the morphological changes, cytological transitions, and underlying transcriptional programming remain to be elucidated. A systemic morphological and cytological study reveals a dynamic developmental process and suggests a common but distinct regulation of the lamina joint. Successive and sequential cell division and expansion, cell wall thickening, and programmed cell death at the adaxial or abaxial sides form the cytological basis of the lamina joint, and the increased leaf angle results from the asymmetric cell proliferation and elongation. Analysis of the gene expression profiles at four distinct developmental stages ranging from initiation to senescence showed that genes related to cell division and growth, hormone synthesis and signaling, transcription (transcription factors), and protein phosphorylation (protein kinases) exhibit distinct spatiotemporal patterns during lamina joint development. Phytohormones play crucial roles by promoting cell differentiation and growth at early stages or regulating the maturation and senescence at later stages, which is consistent with the quantitative analysis of hormones at different stages. Further comparison with the gene expression profile of leaf inclination1 , a mutant with decreased auxin and increased leaf angle, indicates the coordinated effects of hormones in regulating lamina joint. These results reveal a dynamic cytology of rice lamina joint that is fine-regulated by multiple factors, providing informative clues for illustrating the regulatory mechanisms of leaf angle and plant architecture. © 2017 American Society of Plant Biologists. All Rights Reserved.

Nanoporous-Gold-Based Electrode Morphology Libraries for Investigating Structure-Property Relationships in Nucleic Acid Based Electrochemical Biosensors.

PubMed

Matharu, Zimple; Daggumati, Pallavi; Wang, Ling; Dorofeeva, Tatiana S; Li, Zidong; Seker, Erkin

2017-04-19

Nanoporous gold (np-Au) electrode coatings significantly enhance the performance of electrochemical nucleic acid biosensors because of their three-dimensional nanoscale network, high electrical conductivity, facile surface functionalization, and biocompatibility. Contrary to planar electrodes, the np-Au electrodes also exhibit sensitive detection in the presence of common biofouling media due to their porous structure. However, the pore size of the nanomatrix plays a critical role in dictating the extent of biomolecular capture and transport. Small pores perform better in the case of target detection in complex samples by filtering out the large nonspecific proteins. On the other hand, larger pores increase the accessibility of target nucleic acids in the nanoporous structure, enhancing the detection limits of the sensor at the expense of more interference from biofouling molecules. Here, we report a microfabricated np-Au multiple electrode array that displays a range of electrode morphologies on the same chip for identifying feature sizes that reduce the nonspecific adsorption of proteins but facilitate the permeation of target DNA molecules into the pores. We demonstrate the utility of the electrode morphology library in studying DNA functionalization and target detection in complex biological media with a special emphasis on revealing ranges of electrode morphologies that mutually enhance the limit of detection and biofouling resilience. We expect this technique to assist in the development of high-performance biosensors for point-of-care diagnostics and facilitate studies on the electrode structure-property relationships in potential applications ranging from neural electrodes to catalysts.

Metallurgical characterization of orthodontic brackets produced by Metal Injection Molding (MIM).

PubMed

Zinelis, Spiros; Annousaki, Olga; Makou, Margarita; Eliades, Theodore

2005-11-01

The aim of this study was to investigate the bonding base surface morphology, alloy type, microstructure, and hardness of four types of orthodontic brackets produced by Metal Injection Molding technology (Discovery, Extremo, Freedom, and Topic). The bonding base morphology of the brackets was evaluated by scanning electron microscopy (SEM). Brackets from each manufacturer were embedded in epoxy resin, and after metallographic grinding, polishing and coating were analyzed by x-ray energy-dispersive spectroscopic (EDS) microanalysis to assess their elemental composition. Then, the brackets were subjected to metallographic etching to reveal their metallurgical structure. The same specimen surfaces were repolished and used for Vickers microhardness measurements. The results were statistically analyzed with one-way analysis of variance and Student-Newman-Keuls multiple comparison test at the 0.05 level of significance. The findings of SEM observations showed a great variability in the base morphology design among the brackets tested. The x-ray EDS analysis demonstrated that each bracket was manufactured from different ferrous or Co-based alloys. Metallographic analysis showed the presence of a large grain size for the Discovery, Freedom, and Topic brackets and a much finer grain size for the Extremo bracket. Vickers hardness showed great variations among the brackets (Topic: 287 +/- 16, Freedom: 248 +/- 13, Discovery: 214 +/- 12, and Extremo: 154 +/- 9). The results of this study showed that there are significant differences in the base morphology, composition, microstructure, and microhardness among the brackets tested, which may anticipate significant clinical implications.

Explosive morphological diversification of spiny-finned teleost fishes in the aftermath of the end-Cretaceous extinction.

PubMed

Friedman, Matt

2010-06-07

The spiny-finned teleost fishes (Acanthomorpha) include nearly one-third of all living vertebrate species and assume a bewildering array of bodyplans, but the macroevolutionary assembly of modern acanthomorph biodiversity remains largely unexplored. Here, I reconstruct the trajectory of morphological diversification in this major radiation from its first appearance in the Late Cretaceous to the Miocene using a geometric morphometric database comprising more than 600 extinct species known from complete body fossils. The anatomical diversity (disparity) of acanthomorphs is low throughout the Cretaceous, increases sharply and significantly in the wake of the Cretaceous-Palaeogene (K-P) extinction, and shows little change throughout subsequent Cenozoic intervals. This pattern of morphological diversification appears robust to two potential biasing factors: the 'Lagerstätten effect', and the non-random segregation of rare and common taxa along phenotypic axes. Dissecting the trajectory of acanthomorph radiation along phylogenetic lines reveals that the abrupt post-extinction increase in disparity is driven largely by the proliferation of trophically diverse modern groups within Percomorpha, a spiny-fin subclade containing more than 15 000 living species and identified as showing a substantially elevated diversification rate relative to background vertebrate levels. A major component of the Palaeogene acanthomorph radiation reflects colonization of morphospace previously occupied by non-acanthomorph victims of the K-P. However, other aspects of morphological diversification cannot be explained by this simple ecological release model, suggesting that multiple factors contributed to the prolific anatomical radiation of acanthomorphs.

DNA barcoding reveals high diversity of deep-sea octocorals on Hawaiian seamounts

NASA Astrophysics Data System (ADS)

Baco-Taylor, A.; Morgan, N.; LaBelle, B.; Figueroa, D.; Ormos, A.; Cairns, S.; Driskell, A.

2016-02-01

Globally, studies of deep-sea octocoral distribution and diversity have been hampered by a lack of keys and a plethora of unidentified specimens. Even in areas where intensive morphological work has been done, as many as half of the specimens remain unidentified to species or even genus. Recently, a suite of genetic markers have been identified as barcoding proxies for octocorals. Here, we make one of the first attempts at broad-scale application of 3 of these markers, to recent and museum collections of octocorals of approximately 1000 specimens from the Hawaiian Archipelago, to gain a better understanding of the diversity and distribution of deep-sea octocorals there. Sequence results for all 3 markers show a greater number of haplotypes than morphological species. Each of these markers as taken alone has been shown to underestimate species richness. Extrapolating from this we show that morphological work to date on these specimens underestimates species richness by 30-40%, suggesting the diversity of octocorals in the Hawaiian Archipelago is substantially greater than previously thought. The large percentage of haplotypes represented by single individuals suggests that the full diversity of deep-sea octocorals in Hawaii remains drastically undersampled. This work also shows that species ranges based on current species designations are overestimated, with multiple smaller-range haplotypes for given morphological operational taxonomic units. We evaluate these results to assess the usefulness of application of these markers to understanding deep-sea coral distributions in the broader Pacific and beyond.

Simultaneous imaging of cellular morphology and multiple biomarkers using an acousto-optic tunable filter-based bright field microscope.

PubMed

Wachman, Elliot S; Geyer, Stanley J; Recht, Joel M; Ward, Jon; Zhang, Bill; Reed, Murray; Pannell, Chris

2014-05-01

An acousto-optic tunable filter (AOTF)-based multispectral imaging microscope system allows the combination of cellular morphology and multiple biomarker stainings on a single microscope slide. We describe advances in AOTF technology that have greatly improved spectral purity, field uniformity, and image quality. A multispectral imaging bright field microscope using these advances demonstrates pathology results that have great potential for clinical use.

Atypical outbreak of acute coenurosis by Taenia multiceps in a sheep flock.

PubMed

Pintus, Davide; Varcasia, Antonio; Dessì, Giorgia; Tamponi, Claudia; Manunta, Maria Lucia; Carboni, Giovanni Antonio; Cancedda, Maria Giovanna; Ligios, Ciriaco; Scala, Antonio

2018-06-01

Herein, we examined the brain of adult ewes and lambs less than 30 days old which were found affected by neurological signs in a flock located in Sardinia (Italy). Gross anatomo-pathological examination of all brains of the animals revealed multiple linear reddish-yellow foci of necrotic purulent inflammation due to oncosphere migration. Histologically, we confirmed a multifocal pyo-granulomatous meningo-encephalitis both in ewes and in lambs, confirming acute coenurosis. Morphological examination and DNA sequencing identified the Taenia multiceps we isolated as Tm1 strain. This report describes for the first time a natural acute coenurosis infection in suckling lambs under 30 days of age.

Stairway to heaven: evaluating levels of biological organization correlated with the successful ascent of natural waterfalls in the Hawaiian stream goby Sicyopterus stimpsoni.

PubMed

Schoenfuss, Heiko L; Maie, Takashi; Moody, Kristine N; Lesteberg, Kelsey E; Blob, Richard W; Schoenfuss, Tonya C

2013-01-01

Selective pressures generated by locomotor challenges act at the level of the individual. However, phenotypic variation among individuals that might convey a selective advantage may occur across any of multiple levels of biological organization. In this study, we test for differences in external morphology, muscle mechanical advantage, muscle fiber type and protein expression among individuals of the waterfall climbing Hawaiian fish Sicyopterus stimpsoni collected from sequential pools increasing in elevation within a single freshwater stream. Despite predictions from previous laboratory studies of morphological selection, few directional morphometric changes in body shape were observed at successively higher elevations. Similarly, lever arm ratios associated with the main pelvic sucker, central to climbing ability in this species, did not differ between elevations. However, among climbing muscles, the adductor pelvicus complex (largely responsible for generating pelvic suction during climbing) contained a significantly greater red muscle fiber content at upstream sites. A proteomic analysis of the adductor pelvicus revealed two-fold increases in expression levels for two respiratory chain proteins (NADH:ubiquinone reductase and cytochrome b) that are essential for aerobic respiration among individuals from successively higher elevations. Assessed collectively, these evaluations reveal phenotypic differences at some, but not all levels of biological organization that are likely the result of selective pressures experienced during climbing.

Stairway to Heaven: Evaluating Levels of Biological Organization Correlated with the Successful Ascent of Natural Waterfalls in the Hawaiian Stream Goby Sicyopterus stimpsoni

PubMed Central

Schoenfuss, Heiko L.; Maie, Takashi; Moody, Kristine N.; Lesteberg, Kelsey E.; Blob, Richard W.; Schoenfuss, Tonya C.

2013-01-01

Selective pressures generated by locomotor challenges act at the level of the individual. However, phenotypic variation among individuals that might convey a selective advantage may occur across any of multiple levels of biological organization. In this study, we test for differences in external morphology, muscle mechanical advantage, muscle fiber type and protein expression among individuals of the waterfall climbing Hawaiian fish Sicyopterus stimpsoni collected from sequential pools increasing in elevation within a single freshwater stream. Despite predictions from previous laboratory studies of morphological selection, few directional morphometric changes in body shape were observed at successively higher elevations. Similarly, lever arm ratios associated with the main pelvic sucker, central to climbing ability in this species, did not differ between elevations. However, among climbing muscles, the adductor pelvicus complex (largely responsible for generating pelvic suction during climbing) contained a significantly greater red muscle fiber content at upstream sites. A proteomic analysis of the adductor pelvicus revealed two-fold increases in expression levels for two respiratory chain proteins (NADH:ubiquinone reductase and cytochrome b) that are essential for aerobic respiration among individuals from successively higher elevations. Assessed collectively, these evaluations reveal phenotypic differences at some, but not all levels of biological organization that are likely the result of selective pressures experienced during climbing. PMID:24386424

Virus-induced apoptosis and phosphorylation form of metacaspase in the marine coccolithophorid Emiliania huxleyi.

PubMed

Liu, Jingwen; Cai, Weicong; Fang, Xian; Wang, Xueting; Li, Guiling

2018-04-01

Lytic viral infection and programmed cell death (PCD) are thought to represent two distinct death mechanisms in phytoplankton, unicellular photoautotrophs that drift with ocean currents. PCD (apoptosis) is mainly brought about by the activation of caspases, a protease family with unique substrate selectivity. Here, we demonstrated that virus infection induced apoptosis of marine coccolithophorid Emiliania huxleyi BOF92 involving activation of metacaspase. E. huxleyi cells exhibited cell death process akin to that of apoptosis when exposed to virus infection. We observed typical hallmarks of apoptosis including cell shrinkage, associated nuclear morphological changes and DNA fragmentation. Immunoblotting revealed that antibody against human active-caspase-3 shared epitopes with a protein of ≈ 23 kDa; whose pattern of expression correlated with the onset of cell death. Moreover, analysis on two-dimensional gel electrophoresis revealed that two spots of active caspase-3 co-migrated with the different isoelectric points. Phosphatase treatment of cytosolic extracts containing active caspases-3 showed a mobility shift, suggesting that phosphorylated form of this enzyme might be present in the extracts. Computational prediction of phosphorylation sites based on the amino acid sequence of E. huxleyi metacaspase showed multiple phosphorylated sites for serine, threonine and tyrosine residues. This is the first report showing that phosphorylation modification of metacaspase in E. huxleyi might be required for certain biochemical and morphological changes during virus induced apoptosis.

Genetic assessment of ornamental fish species from North East India.

PubMed

Dhar, Bishal; Ghosh, Sankar Kumar

2015-01-25

Ornamental fishes are traded with multiple names from various parts around the world, including North East India. Most are collected from the wild, due to lack of species-specific culture or breeding, and therefore, such unmanaged collection of the wild and endemic species could lead to severe threats to biodiversity. Despite many regulatory policies, trade of threatened species, including the IUCN listed species have been largely uncontrolled, due to species identification problems arising from the utilization of multiple trade names. So, the development of species-specific DNA marker is indispensable where DNA Barcoding is proved to be helpful in species identification. Here, we investigated, through DNA Barcoding and morphological assessment, the identification of 128 ornamental fish specimens exported from NE India from different exporters. The generated sequences were subjected to similarity match in BOLD-IDS as well as BLASTN, and analysed using MEGA5.2 for species identification through Neighbour-Joining (NJ) clustering, and K2P distance based approach. The analysis revealed straightforward identification of 84 specimens into 35 species, while 44 specimens were difficult to distinguish based on CO1 barcode alone. However, these cases were resolved through morphology, NJ and distanced based method and found to be belonging to 16 species. Among the 51 identified species, 14 species represented multiple trade names; 17 species belonged to threatened category. Species-level identification through DNA Barcoding along with traditional morphotaxonomy reflects its efficacy in regulating ornamental fish trade and therefore, appeals for their conservation in nature. The use of trade names rather than the zoological name created the passage for trafficking of the threatened species and demands immediate attention for sustaining wildlife conservation. Copyright © 2014 Elsevier B.V. All rights reserved.

Models of utricular bouton afferents: role of afferent-hair cell connectivity in determining spike train regularity.

PubMed

Holmes, William R; Huwe, Janice A; Williams, Barbara; Rowe, Michael H; Peterson, Ellengene H

2017-05-01

Vestibular bouton afferent terminals in turtle utricle can be categorized into four types depending on their location and terminal arbor structure: lateral extrastriolar (LES), striolar, juxtastriolar, and medial extrastriolar (MES). The terminal arbors of these afferents differ in surface area, total length, collecting area, number of boutons, number of bouton contacts per hair cell, and axon diameter (Huwe JA, Logan CJ, Williams B, Rowe MH, Peterson EH. J Neurophysiol 113: 2420-2433, 2015). To understand how differences in terminal morphology and the resulting hair cell inputs might affect afferent response properties, we modeled representative afferents from each region, using reconstructed bouton afferents. Collecting area and hair cell density were used to estimate hair cell-to-afferent convergence. Nonmorphological features were held constant to isolate effects of afferent structure and connectivity. The models suggest that all four bouton afferent types are electrotonically compact and that excitatory postsynaptic potentials are two to four times larger in MES afferents than in other afferents, making MES afferents more responsive to low input levels. The models also predict that MES and LES terminal structures permit higher spontaneous firing rates than those in striola and juxtastriola. We found that differences in spike train regularity are not a consequence of differences in peripheral terminal structure, per se, but that a higher proportion of multiple contacts between afferents and individual hair cells increases afferent firing irregularity. The prediction that afferents having primarily one bouton contact per hair cell will fire more regularly than afferents making multiple bouton contacts per hair cell has implications for spike train regularity in dimorphic and calyx afferents. NEW & NOTEWORTHY Bouton afferents in different regions of turtle utricle have very different morphologies and afferent-hair cell connectivities. Highly detailed computational modeling provides insights into how morphology impacts excitability and also reveals a new explanation for spike train irregularity based on relative numbers of multiple bouton contacts per hair cell. This mechanism is independent of other proposed mechanisms for spike train irregularity based on ionic conductances and can explain irregularity in dimorphic units and calyx endings. Copyright © 2017 the American Physiological Society.

Single-Copy Nuclear Genes Place Haustorial Hydnoraceae within Piperales and Reveal a Cretaceous Origin of Multiple Parasitic Angiosperm Lineages

PubMed Central

Naumann, Julia; Salomo, Karsten; Der, Joshua P.; Wafula, Eric K.; Bolin, Jay F.; Maass, Erika; Frenzke, Lena; Samain, Marie-Stéphanie; Neinhuis, Christoph

2013-01-01

Extreme haustorial parasites have long captured the interest of naturalists and scientists with their greatly reduced and highly specialized morphology. Along with the reduction or loss of photosynthesis, the plastid genome often decays as photosynthetic genes are released from selective constraint. This makes it challenging to use traditional plastid genes for parasitic plant phylogenetics, and has driven the search for alternative phylogenetic and molecular evolutionary markers. Thus, evolutionary studies, such as molecular clock-based age estimates, are not yet available for all parasitic lineages. In the present study, we extracted 14 nuclear single copy genes (nSCG) from Illumina transcriptome data from one of the “strangest plants in the world”, Hydnora visseri (Hydnoraceae). A ∼15,000 character molecular dataset, based on all three genomic compartments, shows the utility of nSCG for reconstructing phylogenetic relationships in parasitic lineages. A relaxed molecular clock approach with the same multi-locus dataset, revealed an ancient age of ∼91 MYA for Hydnoraceae. We then estimated the stem ages of all independently originated parasitic angiosperm lineages using a published dataset, which also revealed a Cretaceous origin for Balanophoraceae, Cynomoriaceae and Apodanthaceae. With the exception of Santalales, older parasite lineages tend to be more specialized with respect to trophic level and have lower species diversity. We thus propose the “temporal specialization hypothesis” (TSH) implementing multiple independent specialization processes over time during parasitic angiosperm evolution. PMID:24265760

Arrhythmogenic Right Ventricular Cardiomyopathy with Multiple Thrombi and Ventricular Tachycardia of Atypical Left Branch Bundle Block Morphology.

PubMed

Gong, Shenzhen; Wei, Xin; Liu, Guyue; Wu, Feng; Chen, Xiaoping

2018-04-06

A 61-year-old male patient was admitted to our hospital with recurrent palpitations and syncope. Electrocardiography, echocardiography, and contrast-enhanced computed tomography were performed. The patient was diagnosed with arrhythmogenic right ventricular cardiomyopathy (ARVC) complicated by multiple thrombi, and ventricular tachycardia (VT) without typical left bundle branch block (LBBB) morphology. This case suggests that VT is not always the sole contributor to syncope and death in patients with ARVC, and pulmonary embolism should be considered. Furthermore, VT with typical LBBB morphology is not an absolute necessity as a major criterion for the diagnosis of ARVC when the right heart is extremely enlarged.

A rapid and efficient protocol for in vitro multiplication of genetically uniform Stevia rebaudiana (Bertoni).

PubMed

Khan, A; Jayanthi, M; Gantasala, Nagavara Prasad; Bhooshan, N; Rao, Uma

2016-07-01

Stevia rebaudiana (Bertoni), commonly called candy leaf or sweet leaf, endemic to South America, is an important medicinal plant. As a source of low calorie natural sweetener 'stevoside', it is used in obesity, diabetes, treatment of heartburn and tooth decay, and also serves as a food supplement. Large scale commercial propagation of S. rebaudiana demands a suitable protocol. Here, we propose an improved protocol for in vitro multiplication of S. rebaudiana from nodal explants. In this protocol, the effect of laboratory grade urea on multiple shoot induction from nodal explants was studied. The nodal explants were initially cultured on Murashige and Skoog (MS) basal media for 2 weeks which facilitated the axillary bud break. Further, culturing of these explants on MS medium fortified with 6 benzyl amninopurine (BAP) (2 mg/L) and Naphthalene acetic acid (NAA) (1 mg/L) with and .without urea (5 mg/L) for a period of 40 days revealed maximum shoot production of 44.56 from a single nodal explant in media supplemented with urea as compared to 22.44 without urea. The differences in the number of shoots produced were significant and these shoots readily rooted in MS media with NAA (4 mg/L). Primary and secondary hardening was successful in these plants. There were no visible morphological abnormalities observed in the micropropagated plantlets. Genetic analysis from random samples also revealed that these plants are genetically uniform. The advantage of the present protocol is that the complete process of multiple shoot induction, rooting and hardening could be completed within a period of 6 months as compared to the existing protocols.

Comparative Molecular and Morphological Variation Analysis of Siderastrea (Anthozoa, Scleractinia) Reveals the Presence of Siderastrea stellata in the Gulf of Mexico.

PubMed

García, Norberto A Colín; Campos, Jorge E; Musi, José L Tello; Forsman, Zac H; Muñoz, Jorge L Montero; Reyes, Alejandro Monsalvo; González, Jesús E Arias

2017-02-01

The genus Siderastrea exhibits high levels of morphological variability. Some of its species share similar morphological characteristics with congeners, making their identification difficult. Siderastrea stellata has been reported as an intermediary of S. siderea and S. radians in the Brazilian reef ecosystem. In an earlier study conducted in Mexico, we detected Siderastrea colonies with morphological features that were not consistent with some siderastreid species previously reported in the Gulf of Mexico. Thus, we performed a combined morphological and molecular analysis to identify Siderastrea species boundaries from the Gulf of Mexico. Some colonies presented high morphologic variability, with characteristics that corresponded to Siderastrea stellata. Molecular analysis, using the nuclear ITS and ITS2 region, corroborated the morphological results, revealing low genetic variability between S. radians and S. stellata. Since the ITS sequences did not distinguish between Siderastrea species, we used the ITS2 region to differentiate S. stellata from S. radians. This is the first report of Siderastrea stellata and its variability in the Gulf of Mexico that is supported by morphological and molecular analyses.

Barcoding against a paradox? Combined molecular species delineations reveal multiple cryptic lineages in elusive meiofaunal sea slugs

PubMed Central

2012-01-01

Background Many marine meiofaunal species are reported to have wide distributions, which creates a paradox considering their hypothesized low dispersal abilities. Correlated with this paradox is an especially high taxonomic deficit for meiofauna, partly related to a lower taxonomic effort and partly to a high number of putative cryptic species. Molecular-based species delineation and barcoding approaches have been advocated for meiofaunal biodiversity assessments to speed up description processes and uncover cryptic lineages. However, these approaches show sensitivity to sampling coverage (taxonomic and geographic) and the success rate has never been explored on mesopsammic Mollusca. Results We collected the meiofaunal sea-slug Pontohedyle (Acochlidia, Heterobranchia) from 28 localities worldwide. With a traditional morphological approach, all specimens fall into two morphospecies. However, with a multi-marker genetic approach, we reveal multiple lineages that are reciprocally monophyletic on single and concatenated gene trees in phylogenetic analyses. These lineages are largely concordant with geographical and oceanographic parameters, leading to our primary species hypothesis (PSH). In parallel, we apply four independent methods of molecular based species delineation: General Mixed Yule Coalescent model (GMYC), statistical parsimony, Bayesian Species Delineation (BPP) and Automatic Barcode Gap Discovery (ABGD). The secondary species hypothesis (SSH) is gained by relying only on uncontradicted results of the different approaches (‘minimum consensus approach’), resulting in the discovery of a radiation of (at least) 12 mainly cryptic species, 9 of them new to science, some sympatric and some allopatric with respect to ocean boundaries. However, the meiofaunal paradox still persists in some Pontohedyle species identified here with wide coastal and trans-archipelago distributions. Conclusions Our study confirms extensive, morphologically cryptic diversity among meiofauna and accentuates the taxonomic deficit that characterizes meiofauna research. We observe for Pontohedyle slugs a high degree of morphological simplicity and uniformity, which we expect might be a general rule for meiofauna. To tackle cryptic diversity in little explored and hard-to-sample invertebrate taxa, at present, a combined approach seems most promising, such as multi-marker-barcoding (i.e., molecular systematics using mitochondrial and nuclear markers and the criterion of reciprocal monophyly) combined with a minimum consensus approach across independent methods of molecular species delineation to define candidate species. PMID:23244441

Complete Volumetric Decomposition of Individual Trabecular Plates and Rods and Its Morphological Correlations With Anisotropic Elastic Moduli in Human Trabecular Bone

PubMed Central

Liu, X Sherry; Sajda, Paul; Saha, Punam K; Wehrli, Felix W; Bevill, Grant; Keaveny, Tony M; Guo, X Edward

2008-01-01

Trabecular plates and rods are important microarchitectural features in determining mechanical properties of trabecular bone. A complete volumetric decomposition of individual trabecular plates and rods was used to assess the orientation and morphology of 71 human trabecular bone samples. The ITS-based morphological analyses better characterize microarchitecture and help predict anisotropic mechanical properties of trabecular bone. Introduction Standard morphological analyses of trabecular architecture lack explicit segmentations of individual trabecular plates and rods. In this study, a complete volumetric decomposition technique was developed to segment trabecular bone microstructure into individual plates and rods. Contributions of trabecular type–associated morphological parameters to the anisotropic elastic moduli of trabecular bone were studied. Materials and Methods Seventy-one human trabecular bone samples from the femoral neck (FN), tibia, and vertebral body (VB) were imaged using μCT or serial milling. Complete volumetric decomposition was applied to segment trabecular bone microstructure into individual plates and rods. The orientation of each individual trabecula was determined, and the axial bone volume fractions (aBV/TV), axially aligned bone volume fraction along each orthotropic axis, were correlated with the elastic moduli. The microstructural type–associated morphological parameters were derived and compared with standard morphological parameters. Their contributions to the anisotropic elastic moduli, calculated by finite element analysis (FEA), were evaluated and compared. Results The distribution of trabecular orientation suggested that longitudinal plates and transverse rods dominate at all three anatomic sites. aBV/TV along each axis, in general, showed a better correlation with the axial elastic modulus (r 2 = 0.95∼0.99) compared with BV/TV (r 2 = 0.93∼0.94). The plate-associated morphological parameters generally showed higher correlations with the corresponding standard morphological parameters than the rod-associated parameters. Multiple linear regression models of six elastic moduli with individual trabeculae segmentation (ITS)-based morphological parameters (adjusted r 2 = 0.95∼0.98) performed equally well as those with standard morphological parameters (adjusted r 2 = 0.94∼0.97) but revealed specific contributions from individual trabecular plates or rods. Conclusions The ITS-based morphological analyses provide a better characterization of the morphology and trabecular orientation of trabecular bone. The axial loading of trabecular bone is mainly sustained by the axially aligned trabecular bone volume. Results suggest that trabecular plates dominate the overall elastic properties of trabecular bone. PMID:17907921

Coordinately Co-opted Multiple Transposable Elements Constitute an Enhancer for wnt5a Expression in the Mammalian Secondary Palate

PubMed Central

Kimura-Yoshida, Chiharu; Yan, Kuo; Bormuth, Olga; Ding, Qiong; Nakanishi, Akiko; Sasaki, Takeshi; Hirakawa, Mika; Sumiyama, Kenta; Furuta, Yasuhide; Tarabykin, Victor; Matsuo, Isao; Okada, Norihiro

2016-01-01

Acquisition of cis-regulatory elements is a major driving force of evolution, and there are several examples of developmental enhancers derived from transposable elements (TEs). However, it remains unclear whether one enhancer element could have been produced via cooperation among multiple, yet distinct, TEs during evolution. Here we show that an evolutionarily conserved genomic region named AS3_9 comprises three TEs (AmnSINE1, X6b_DNA and MER117), inserted side-by-side, and functions as a distal enhancer for wnt5a expression during morphogenesis of the mammalian secondary palate. Functional analysis of each TE revealed step-by-step retroposition/transposition and co-option together with acquisition of a binding site for Msx1 for its full enhancer function during mammalian evolution. The present study provides a new perspective suggesting that a huge variety of TEs, in combination, could have accelerated the diversity of cis-regulatory elements involved in morphological evolution. PMID:27741242

Spontaneous Epithelioid Hemangiosarcoma in a Rhesus Monkey (Macaca mulatta)

PubMed Central

Tsuchiya, Takayuki; Gray, Tasha L; Gatto, Nicholas T; Forest, Thomas; Machotka, Sam V; Troth, Sean P; Prahalada, Srinivasa

2014-01-01

Epithelioid hemangiosarcoma is a rare malignant endothelial neoplasia with a unique, predominantly epithelioid morphology. A 4-y-old rhesus monkey from our laboratory had multiple neoplastic nodules in a digit, limb skin, hindlimb muscle, and visceral organs including lung, heart, and brain. The nodules were composed of pleomorphic, polygonal, epithelioid, neoplastic cells that were arranged in sheets, nests, and cords and supported by variably dense fibrovascular connective tissue. The morphologic features of this tumor were predominantly epithelioid. However, some regions contained cystic spaces, clefts, and channel-like structures, all of which were lined with morphologically distinct neoplastic endothelial cells. These neoplastic cells, with or without epithelioid morphology, were positive immunohistochemically for CD31, factor VIII-related antigen, and vimentin. The presence of multiple metastatic nodules, high mitotic rate, and extensive Ki67-positive staining were consistent with malignancy. This report is the first description of epithelioid hemangiosarcoma in a rhesus monkey. PMID:25296017

Spontaneous epithelioid hemangiosarcoma in a rhesus monkey (Macaca mulatta).

PubMed

Tsuchiya, Takayuki; Gray, Tasha L; Gatto, Nicholas T; Forest, Thomas; Machotka, Sam V; Troth, Sean P; Prahalada, Srinivasa

2014-08-01

Epithelioid hemangiosarcoma is a rare malignant endothelial neoplasia with a unique, predominantly epithelioid morphology. A 4-y-old rhesus monkey from our laboratory had multiple neoplastic nodules in a digit, limb skin, hindlimb muscle, and visceral organs including lung, heart, and brain. The nodules were composed of pleomorphic, polygonal, epithelioid, neoplastic cells that were arranged in sheets, nests, and cords and supported by variably dense fibrovascular connective tissue. The morphologic features of this tumor were predominantly epithelioid. However, some regions contained cystic spaces, clefts, and channel-like structures, all of which were lined with morphologically distinct neoplastic endothelial cells. These neoplastic cells, with or without epithelioid morphology, were positive immunohistochemically for CD31, factor VIII-related antigen, and vimentin. The presence of multiple metastatic nodules, high mitotic rate, and extensive Ki67-positive staining were consistent with malignancy. This report is the first description of epithelioid hemangiosarcoma in a rhesus monkey.

1,4-Naphthoquinone derivatives potently suppress Candida albicans growth, inhibit formation of hyphae and show no toxicity toward zebrafish embryos.

PubMed

Janeczko, Monika; Kubiński, Konrad; Martyna, Aleksandra; Muzyczka, Angelika; Boguszewska-Czubara, Anna; Czernik, Sławomir; Tokarska-Rodak, Małgorzata; Chwedczuk, Marta; Demchuk, Oleg M; Golczyk, Hieronim; Masłyk, Maciej

2018-04-01

In this study, we applied various assays to find new activities of 1,4-naphthoquinone derivatives for potential anti-Candida albicans applications. These assays determined (a) the antimicrobial effect on growth/cell multiplication in fungal cultures, (b) the effect on formation of hyphae and biofilm, (c) the influence on cell membrane integrity, (d) the effect on cell morphology using atomic force microscopy, and (e) toxicity against zebrafish embryos. We have demonstrated the activity of these compounds against different Candida species and clinical isolates of C. albicans. 1,4-Naphthoquinones significantly affected fungal strains at 8-250 mg l -1 of MIC. Interestingly, at concentrations below MICs, the chemicals showed effectiveness in inhibition of hyphal formation and cell aggregation in Candida. Of note, atomic force microscopy (AFM) analysis revealed an influence of the compounds on cell morphological properties. However, at low concentrations (0.8-31.2 mg l -1 ), it did not exert any evident toxic effects on zebrafish embryos. Our research has evidenced the effectiveness of 1,4-naphthoquinones as potential anti-Candida agents.

Using tethered triblock copolymers to mediate the interaction between substrates

NASA Astrophysics Data System (ADS)

Chern, Shyh-Shi; Zhulina, Ekaterina B.; Pickett, Galen T.; Balazs, Anna C.

1998-04-01

Using scaling analysis and a self-consistent field (SCF) theory, we compress two copolymer-coated surfaces and isolate conditions that yield multiple, distinct minima in the interaction profile. We focus on planar surfaces that are coated with ABC triblock copolymers. Tethered to the surface by the last monomer in the C block, the copolymers are grafted at relatively low densities. The surrounding solution is a poor solvent for both the A and C blocks, and is a good solvent for the B blocks. Through scaling theory, we pinpoint the parameters that yield two minima in the interaction profile. The SCF calculations reveal the changes in the morphology of the polymers as the layers are compressed. Through both studies, we determine how the morphological changes give rise to the observed surface interactions. The results provide guidelines for creating polymer-coated colloidal systems that can form two stable crystal structures. Such systems could be used for bistable, optical switches. The findings also yield a prescription for creating systems that exhibit additional minima in the free energy of interaction.

Neural Correlates of Morphology Acquisition through a Statistical Learning Paradigm.

PubMed

Sandoval, Michelle; Patterson, Dianne; Dai, Huanping; Vance, Christopher J; Plante, Elena

2017-01-01

The neural basis of statistical learning as it occurs over time was explored with stimuli drawn from a natural language (Russian nouns). The input reflected the "rules" for marking categories of gendered nouns, without making participants explicitly aware of the nature of what they were to learn. Participants were scanned while listening to a series of gender-marked nouns during four sequential scans, and were tested for their learning immediately after each scan. Although participants were not told the nature of the learning task, they exhibited learning after their initial exposure to the stimuli. Independent component analysis of the brain data revealed five task-related sub-networks. Unlike prior statistical learning studies of word segmentation, this morphological learning task robustly activated the inferior frontal gyrus during the learning period. This region was represented in multiple independent components, suggesting it functions as a network hub for this type of learning. Moreover, the results suggest that subnetworks activated by statistical learning are driven by the nature of the input, rather than reflecting a general statistical learning system.

Neural Correlates of Morphology Acquisition through a Statistical Learning Paradigm

PubMed Central

Sandoval, Michelle; Patterson, Dianne; Dai, Huanping; Vance, Christopher J.; Plante, Elena

2017-01-01

The neural basis of statistical learning as it occurs over time was explored with stimuli drawn from a natural language (Russian nouns). The input reflected the “rules” for marking categories of gendered nouns, without making participants explicitly aware of the nature of what they were to learn. Participants were scanned while listening to a series of gender-marked nouns during four sequential scans, and were tested for their learning immediately after each scan. Although participants were not told the nature of the learning task, they exhibited learning after their initial exposure to the stimuli. Independent component analysis of the brain data revealed five task-related sub-networks. Unlike prior statistical learning studies of word segmentation, this morphological learning task robustly activated the inferior frontal gyrus during the learning period. This region was represented in multiple independent components, suggesting it functions as a network hub for this type of learning. Moreover, the results suggest that subnetworks activated by statistical learning are driven by the nature of the input, rather than reflecting a general statistical learning system. PMID:28798703

High-resolution UV-visible spectroscopy of lunar red spots

NASA Technical Reports Server (NTRS)

Bruno, B. C.; Lucey, P. G.; Hawke, B. R.

1991-01-01

A spectral reflectance study of selected lunar 'red spots', highland areas characterized by an absorption in the ultraviolet relative to the visible was conducted. Some red spots were suggested to be the sites of ancient highland volcanism. High-resolution spectral data of eight red spots on the western portion of the moon over the wavelength region 0.39-0.82 micron were obtained. Much spectral variation among these red spots in the magnitude as well as the wavelength position of the ultraviolet absorption were found. Spectral structure at visible and near-infrared wavelength were also identified. These spectral differences indicate that red spots do not have a single mineralogical composition, which in turn suggests that red spots may have multiple origins. Additional imaging spectroscopic observations were taken of the Herigonius red spot, a morphologically complex region northeast of Mare Humorum. These data reveal significant spectral differences among the various morphological units within the Herigonius red spot. Although some of these are likely due to the effects of the maturation process, others appear to reflect differences in mineral abundances and composition.

Enrichment of dynamic chromosomal crosslinks drive phase separation of the nucleolus.

PubMed

Hult, Caitlin; Adalsteinsson, David; Vasquez, Paula A; Lawrimore, Josh; Bennett, Maggie; York, Alyssa; Cook, Diana; Yeh, Elaine; Forest, Mark Gregory; Bloom, Kerry

2017-11-02

Regions of highly repetitive DNA, such as those found in the nucleolus, show a self-organization that is marked by spatial segregation and frequent self-interaction. The mechanisms that underlie the sequestration of these sub-domains are largely unknown. Using a stochastic, bead-spring representation of chromatin in budding yeast, we find enrichment of protein-mediated, dynamic chromosomal cross-links recapitulates the segregation, morphology and self-interaction of the nucleolus. Rates and enrichment of dynamic crosslinking have profound consequences on domain morphology. Our model demonstrates the nucleolus is phase separated from other chromatin in the nucleus and predicts that multiple rDNA loci will form a single nucleolus independent of their location within the genome. Fluorescent labeling of budding yeast nucleoli with CDC14-GFP revealed that a split rDNA locus indeed forms a single nucleolus. We propose that nuclear sub-domains, such as the nucleolus, result from phase separations within the nucleus, which are driven by the enrichment of protein-mediated, dynamic chromosomal crosslinks. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

Identification of Characteristic Macromolecules of Escherichia coli Genotypes by Atomic Force Microscope Nanoscale Mechanical Mapping

NASA Astrophysics Data System (ADS)

Chang, Alice Chinghsuan; Liu, Bernard Haochih

2018-02-01

The categorization of microbial strains is conventionally based on the molecular method, and seldom are the morphological characteristics in the bacterial strains studied. In this research, we revealed the macromolecular structures of the bacterial surface via AFM mechanical mapping, whose resolution was not only determined by the nanoscale tip size but also the mechanical properties of the specimen. This technique enabled the nanoscale study of membranous structures of microbial strains with simple specimen preparation and flexible working environments, which overcame the multiple restrictions in electron microscopy and label-enable biochemical analytical methods. The characteristic macromolecules located among cellular surface were considered as surface layer proteins and were found to be specific to the Escherichia coli genotypes, from which the averaged molecular sizes were characterized with diameters ranging from 38 to 66 nm, and the molecular shapes were kidney-like or round. In conclusion, the surface macromolecular structures have unique characteristics that link to the E. coli genotype, which suggests that the genomic effects on cellular morphologies can be rapidly identified using AFM mechanical mapping. [Figure not available: see fulltext.

Species delimitation in lemurs: multiple genetic loci reveal low levels of species diversity in the genus Cheirogaleus

PubMed Central

Groeneveld, Linn F; Weisrock, David W; Rasoloarison, Rodin M; Yoder, Anne D; Kappeler, Peter M

2009-01-01

Background Species are viewed as the fundamental unit in most subdisciplines of biology. To conservationists this unit represents the currency for global biodiversity assessments. Even though Madagascar belongs to one of the top eight biodiversity hotspots of the world, the taxonomy of its charismatic lemuriform primates is not stable. Within the last 25 years, the number of described lemur species has more than doubled, with many newly described species identified among the nocturnal and small-bodied cheirogaleids. Here, we characterize the diversity of the dwarf lemurs (genus Cheirogaleus) and assess the status of the seven described species, based on phylogenetic and population genetic analysis of mtDNA (cytb + cox2) and three nuclear markers (adora3, fiba and vWF). Results This study identified three distinct evolutionary lineages within the genus Cheirogaleus. Population genetic cluster analyses revealed a further layer of population divergence with six distinct genotypic clusters. Conclusion Based on the general metapopulation lineage concept and multiple concordant data sets, we identify three exclusive groups of dwarf lemur populations that correspond to three of the seven named species: C. major, C. medius and C. crossleyi. These three species were found to be genealogically exclusive in both mtDNA and nDNA loci and are morphologically distinguishable. The molecular and morphometric data indicate that C. adipicaudatus and C. ravus are synonymous with C. medius and C. major, respectively. Cheirogaleus sibreei falls into the C. medius mtDNA clade, but in morphological analyses the membership is not clearly resolved. We do not have sufficient data to assess the status of C. minusculus. Although additional patterns of population differentiation are evident, there are no clear subdivisions that would warrant additional specific status. We propose that ecological and more geographic data should be collected to confirm these results. PMID:19193227

Does weather shape rodents? Climate related changes in morphology of two heteromyid species

NASA Astrophysics Data System (ADS)

Wolf, Mosheh; Friggens, Michael; Salazar-Bravo, Jorge

2009-01-01

Geographical variation in morphometric characters in heteromyid rodents has often correlated with climate gradients. Here, we used the long-term database of rodents trapped in the Sevilleta National Wildlife Refuge in New Mexico, USA to test whether significant annual changes in external morphometric characters are observed in a region with large variations in temperature and precipitation. We looked at the relationships between multiple temperature and precipitation variables and a number of morphological traits (body mass, body, tail, hind leg, and ear length) for two heteromyid rodents, Dipodomys merriami and Perognathus flavescens. Because these rodents can live multiple years in the wild, the climate variables for the year of the capture and the previous 2 years were included in the analyses. Using multiple linear regressions, we found that all of our morphometric traits, with the exception of tail length in D. merriami, had a significant relationship with one or more of the climate variables used. Our results demonstrate that effects of climate change on morphological traits occur over short periods, even in noninsular mammal populations. It is unclear, though, whether these changes are the result of morphological plasticity or natural selection.

EVALUATING THE MORPHOLOGY OF THE LOCAL INTERSTELLAR MEDIUM: USING NEW DATA TO DISTINGUISH BETWEEN MULTIPLE DISCRETE CLOUDS AND A CONTINUOUS MEDIUM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Redfield, Seth; Linsky, Jeffrey L., E-mail: sredfield@wesleyan.edu, E-mail: jlinsky@jila.colorado.edu

Ultraviolet and optical spectra of interstellar gas along the lines of sight to nearby stars have been interpreted by Redfield and Linsky and previous studies as a set of discrete warm, partially ionized clouds each with a different flow vector, temperature, and metal depletion. Recently, Gry and Jenkins proposed a fundamentally different model consisting of a single cloud with nonrigid flows filling space out to 9 pc from the Sun that they propose better describes the local ISM. Here we test these fundamentally different morphological models against the spatially unbiased Malamut et al. spectroscopic data set, and find that themore » multiple cloud morphology model provides a better fit to both the new and old data sets. The detection of three or more velocity components along the lines of sight to many nearby stars, the presence of nearby scattering screens, the observed thin elongated structures of warm interstellar gas, and the likely presence of strong interstellar magnetic fields also support the multiple cloud model. The detection and identification of intercloud gas and the measurement of neutral hydrogen density in clouds beyond the Local Interstellar Cloud could provide future morphological tests.« less

Does polyandry really pay off? The effects of multiple mating and number of fathers on morphological traits and survival in clutches of nesting green turtles at Tortuguero.

PubMed

Alfaro-Núñez, Alonzo; Jensen, Michael P; Abreu-Grobois, F Alberto

2015-01-01

Despite the long debate of whether or not multiple mating benefits the offspring, studies still show contradictory results. Multiple mating takes time and energy. Thus, if females fertilize their eggs with a single mating, why to mate more than once? We investigated and inferred paternal identity and number of sires in 12 clutches (240 hatchlings) of green turtles (Chelonia mydas) nests at Tortuguero, Costa Rica. Paternal alleles were inferred through comparison of maternal and hatchling genotypes, and indicated multiple paternity in at least 11 of the clutches (92%). The inferred average number of fathers was three (ranging from 1 to 5). Moreover, regression analyses were used to investigate for correlation of inferred clutch paternity with morphological traits of hatchlings fitness (emergence success, length, weight and crawling speed), the size of the mother, and an environmental variable (incubation temperature). We suggest and propose two different comparative approaches for evaluating morphological traits and clutch paternity, in order to infer greater offspring survival. First, clutches coded by the exact number of fathers and second by the exact paternal contribution (fathers who gives greater proportion of the offspring per nest). We found significant differences (P < 0.05) in clutches coded by the exact number of fathers for all morphological traits. A general tendency of higher values in offspring sired by two to three fathers was observed for the length and weight traits. However, emergence success and crawling speed showed different trends which unable us to reach any further conclusion. The second approach analysing the paternal contribution showed no significant difference (P > 0.05) for any of the traits. We conclude that multiple paternity does not provide any extra benefit in the morphological fitness traits or the survival of the offspring, when analysed following the proposed comparative statistical methods.

Validation of the Lung Subtyping Panel in Multiple Fresh-Frozen and Formalin-Fixed, Paraffin-Embedded Lung Tumor Gene Expression Data Sets.

PubMed

Faruki, Hawazin; Mayhew, Gregory M; Fan, Cheng; Wilkerson, Matthew D; Parker, Scott; Kam-Morgan, Lauren; Eisenberg, Marcia; Horten, Bruce; Hayes, D Neil; Perou, Charles M; Lai-Goldman, Myla

2016-06-01

Context .- A histologic classification of lung cancer subtypes is essential in guiding therapeutic management. Objective .- To complement morphology-based classification of lung tumors, a previously developed lung subtyping panel (LSP) of 57 genes was tested using multiple public fresh-frozen gene-expression data sets and a prospectively collected set of formalin-fixed, paraffin-embedded lung tumor samples. Design .- The LSP gene-expression signature was evaluated in multiple lung cancer gene-expression data sets totaling 2177 patients collected from 4 platforms: Illumina RNAseq (San Diego, California), Agilent (Santa Clara, California) and Affymetrix (Santa Clara) microarrays, and quantitative reverse transcription-polymerase chain reaction. Gene centroids were calculated for each of 3 genomic-defined subtypes: adenocarcinoma, squamous cell carcinoma, and neuroendocrine, the latter of which encompassed both small cell carcinoma and carcinoid. Classification by LSP into 3 subtypes was evaluated in both fresh-frozen and formalin-fixed, paraffin-embedded tumor samples, and agreement with the original morphology-based diagnosis was determined. Results .- The LSP-based classifications demonstrated overall agreement with the original clinical diagnosis ranging from 78% (251 of 322) to 91% (492 of 538 and 869 of 951) in the fresh-frozen public data sets and 84% (65 of 77) in the formalin-fixed, paraffin-embedded data set. The LSP performance was independent of tissue-preservation method and gene-expression platform. Secondary, blinded pathology review of formalin-fixed, paraffin-embedded samples demonstrated concordance of 82% (63 of 77) with the original morphology diagnosis. Conclusions .- The LSP gene-expression signature is a reproducible and objective method for classifying lung tumors and demonstrates good concordance with morphology-based classification across multiple data sets. The LSP panel can supplement morphologic assessment of lung cancers, particularly when classification by standard methods is challenging.

Fractal branching organizations of Ediacaran rangeomorph fronds reveal a lost Proterozoic body plan.

PubMed

Hoyal Cuthill, Jennifer F; Conway Morris, Simon

2014-09-09

The branching morphology of Ediacaran rangeomorph fronds has no exact counterpart in other complex macroorganisms. As such, these fossils pose major questions as to growth patterns, functional morphology, modes of feeding, and adaptive optimality. Here, using parametric Lindenmayer systems, a formal model of rangeomorph morphologies reveals a fractal body plan characterized by self-similar, axial, apical, alternate branching. Consequent morphological reconstruction for 11 taxa demonstrates an adaptive radiation based on 3D space-filling strategies. The fractal body plan of rangeomorphs is shown to maximize surface area, consistent with diffusive nutrient uptake from the water column (osmotrophy). The enigmas of rangeomorph morphology, evolution, and extinction are resolved by the realization that they were adaptively optimized for unique ecological and geochemical conditions in the late Proterozoic. Changes in ocean conditions associated with the Cambrian explosion sealed their fate.

Multi-scale X-ray Microtomography Imaging of Immiscible Fluids After Imbibition

NASA Astrophysics Data System (ADS)

Garing, C.; de Chalendar, J.; Voltolini, M.; Ajo Franklin, J. B.; Benson, S. M.

2015-12-01

A major issue for CO2 storage security is the efficiency and long-term reliability of the trapping mechanisms occurring in the reservoir where CO2 is injected. Residual trapping is one of the key processes for storage security beyond the primary stratigraphic seal. Although classical conceptual models of residual fluid trapping assume that disconnected ganglia are permanently immobilized, multiple mechanisms exist which could allow the remobilization of residually trapped CO2. The aim of this study is to quantify fluid phases saturation, connectivity and morphology after imbibition using x-ray microtomography in order to evaluate potential changes in droplets organization due to differences in capillary pressure between disconnected ganglia. Particular emphasis is placed on the effect of image resolution. Synchrotron-based x-ray microtomographic datasets of air-water spontaneous imbibition were acquired in sintered glass beads and sandstone samples with voxel sizes varying from 0.64 to 4.44 μm. The results show that for both sandstones the residual air phase is homogeneously distributed within the entire pore space and consists of disconnected clusters of multiple sizes and morphologies. The multi-scale analysis of subsamples of few pores and throats imaged at the same location of the sample reveals significant variations in the estimation of connectivity, size and shape of the fluid phases. This is particularly noticeable when comparing the results from the images with voxel sizes above 1 μm with the results from the images acquired with voxel sizes below 1 μm.

Comparison of structure, morphology, and leach characteristics of multi-phase ceramics produced via melt processing and hot isostatic pressing

NASA Astrophysics Data System (ADS)

Dandeneau, Christopher S.; Hong, Tao; Brinkman, Kyle S.; Vance, Eric R.; Amoroso, Jake W.

2018-04-01

Melt processing of multi-phase ceramic waste forms offers potential advantages over traditional solid-state synthesis methods given both the prevalence of melters currently in use and the ability to reduce the possibility of airborne radionuclide contamination. In this work, multi-phase ceramics with a targeted hollandite composition of Ba1.0Cs0.3Cr1.0Al0.3Fe1.0Ti5.7O16 were fabricated by melt processing at 1675 °C and hot isostatic pressing (HIP) at 1250 and 1300 °C. X-ray diffraction analysis (XRD) confirmed hollandite as the major phase in all specimens. Zirconolite/pyrochlore peaks and weaker perovskite reflections were observed after melt processing, while HIP samples displayed prominent perovskite peaks and low-intensity zirconolite reflections. Melt processing produced specimens with large (>50 μm) well-defined hollandite grains, while HIP yielded samples with a more fine-grained morphology. Elemental analysis showed "islands" rich in Cs and Ti across the surface of the 1300 °C HIP sample, suggesting partial melting and partitioning of Cs into multiple phases. Photoemission data revealed multiple Cs 3d spin-orbit pairs for the HIP samples, with the lower binding energy doublets likely corresponding to Cs located in more leachable phases. Among all specimens examined, the melt-processed sample exhibited the lowest fractional release rates for Rb and Cs. However, the retention of Sr and Mo was greater in the HIP specimens.

Episodic radiations in the fly tree of life

PubMed Central

Wiegmann, Brian M.; Trautwein, Michelle D.; Winkler, Isaac S.; Barr, Norman B.; Kim, Jung-Wook; Lambkin, Christine; Bertone, Matthew A.; Cassel, Brian K.; Bayless, Keith M.; Heimberg, Alysha M.; Wheeler, Benjamin M.; Peterson, Kevin J.; Pape, Thomas; Sinclair, Bradley J.; Skevington, Jeffrey H.; Blagoderov, Vladimir; Caravas, Jason; Kutty, Sujatha Narayanan; Schmidt-Ott, Urs; Kampmeier, Gail E.; Thompson, F. Christian; Grimaldi, David A.; Beckenbach, Andrew T.; Courtney, Gregory W.; Friedrich, Markus; Meier, Rudolf; Yeates, David K.

2011-01-01

Flies are one of four superradiations of insects (along with beetles, wasps, and moths) that account for the majority of animal life on Earth. Diptera includes species known for their ubiquity (Musca domestica house fly), their role as pests (Anopheles gambiae malaria mosquito), and their value as model organisms across the biological sciences (Drosophila melanogaster). A resolved phylogeny for flies provides a framework for genomic, developmental, and evolutionary studies by facilitating comparisons across model organisms, yet recent research has suggested that fly relationships have been obscured by multiple episodes of rapid diversification. We provide a phylogenomic estimate of fly relationships based on molecules and morphology from 149 of 157 families, including 30 kb from 14 nuclear loci and complete mitochondrial genomes combined with 371 morphological characters. Multiple analyses show support for traditional groups (Brachycera, Cyclorrhapha, and Schizophora) and corroborate contentious findings, such as the anomalous Deuterophlebiidae as the sister group to all remaining Diptera. Our findings reveal that the closest relatives of the Drosophilidae are highly modified parasites (including the wingless Braulidae) of bees and other insects. Furthermore, we use micro-RNAs to resolve a node with implications for the evolution of embryonic development in Diptera. We demonstrate that flies experienced three episodes of rapid radiation—lower Diptera (220 Ma), lower Brachycera (180 Ma), and Schizophora (65 Ma)—and a number of life history transitions to hematophagy, phytophagy, and parasitism in the history of fly evolution over 260 million y. PMID:21402926

A retrospective study: correlation of histologic inflammation in biopsy specimens of Chinese men undergoing surgery for benign prostatic hyperplasia with serum prostate-specific antigen.

PubMed

Song, Lingmin; Zhu, Yuchun; Han, Ping; Chen, Ni; Lin, Dao; Lai, Jianyu; Wei, Qiang

2011-03-01

To reveal the correlation between benign prostatic hyperplasia (BPH) histologic inflammation and serum prostate-specific antigen (sPSA) concentrations, and the possible mechanism. Patients underwent surgery at the Urology Department of West China Hospital of Sichuan University were retrospectively studied. Preoperative sPSA and transrectal ultrasonography were measured. According to the histopathological classification system for chronic prostatic inflammation proposed by the Chronic Prostatitis Collaborative Research Network (CPCRN) and the International Prostatitis Collaborative Network (IPCN), we classified the histologic sections of prostatic biopsy into glandular, periglandular, and stromal inflammation by the anatomical location of inflammatory infiltration. The glandular inflammation was graded according to the inflammatory aggressiveness. The periglandular and stromal inflammation were graded according to the inflammatory density. The correlation between histologic inflammation and sPSA was studied by a multiple regression model in conjunction with age and total prostatic volume. A total of 454 patients with exclusively BPH were analyzed. The periglandular inflammatory infiltration was the most common pattern (95.6%). Single regression analysis revealed that total prostatic volume, the aggressiveness of glandular inflammation, and the intensity of periglandular and stromal inflammation were correlated with sPSA. However, the multiple regression analysis revealed that only the total prostatic volume and the aggressiveness of glandular inflammation were correlated significantly with sPSA (R = .389, 0.289; P = .000). The aggressiveness of glandular inflammatory infiltration in BPH is a significant contributor to elevated sPSA levels. The theory of leakage may be the most reasonable mechanism to reveal the correlation morphologically. We should take inflammation into consideration when interpreting the abnormal elevating of sPSA levels. Copyright © 2011 Elsevier Inc. All rights reserved.

Analyzing Mosquito (Diptera: Culicidae) Diversity in Pakistan by DNA Barcoding

PubMed Central

Ashfaq, Muhammad; Hebert, Paul D. N.; Mirza, Jawwad H.; Khan, Arif M.; Zafar, Yusuf; Mirza, M. Sajjad

2014-01-01

Background Although they are important disease vectors mosquito biodiversity in Pakistan is poorly known. Recent epidemics of dengue fever have revealed the need for more detailed understanding of the diversity and distributions of mosquito species in this region. DNA barcoding improves the accuracy of mosquito inventories because morphological differences between many species are subtle, leading to misidentifications. Methodology/Principal Findings Sequence variation in the barcode region of the mitochondrial COI gene was used to identify mosquito species, reveal genetic diversity, and map the distribution of the dengue-vector species in Pakistan. Analysis of 1684 mosquitoes from 491 sites in Punjab and Khyber Pakhtunkhwa during 2010–2013 revealed 32 species with the assemblage dominated by Culex quinquefasciatus (61% of the collection). The genus Aedes (Stegomyia) comprised 15% of the specimens, and was represented by six taxa with the two dengue vector species, Ae. albopictus and Ae. aegypti, dominant and broadly distributed. Anopheles made up another 6% of the catch with An. subpictus dominating. Barcode sequence divergence in conspecific specimens ranged from 0–2.4%, while congeneric species showed from 2.3–17.8% divergence. A global haplotype analysis of disease-vectors showed the presence of multiple haplotypes, although a single haplotype of each dengue-vector species was dominant in most countries. Geographic distribution of Ae. aegypti and Ae. albopictus showed the later species was dominant and found in both rural and urban environments. Conclusions As the first DNA-based analysis of mosquitoes in Pakistan, this study has begun the construction of a barcode reference library for the mosquitoes of this region. Levels of genetic diversity varied among species. Because of its capacity to differentiate species, even those with subtle morphological differences, DNA barcoding aids accurate tracking of vector populations. PMID:24827460

Analyzing mosquito (Diptera: culicidae) diversity in Pakistan by DNA barcoding.

PubMed

Ashfaq, Muhammad; Hebert, Paul D N; Mirza, Jawwad H; Khan, Arif M; Zafar, Yusuf; Mirza, M Sajjad

2014-01-01

Although they are important disease vectors mosquito biodiversity in Pakistan is poorly known. Recent epidemics of dengue fever have revealed the need for more detailed understanding of the diversity and distributions of mosquito species in this region. DNA barcoding improves the accuracy of mosquito inventories because morphological differences between many species are subtle, leading to misidentifications. Sequence variation in the barcode region of the mitochondrial COI gene was used to identify mosquito species, reveal genetic diversity, and map the distribution of the dengue-vector species in Pakistan. Analysis of 1684 mosquitoes from 491 sites in Punjab and Khyber Pakhtunkhwa during 2010-2013 revealed 32 species with the assemblage dominated by Culex quinquefasciatus (61% of the collection). The genus Aedes (Stegomyia) comprised 15% of the specimens, and was represented by six taxa with the two dengue vector species, Ae. albopictus and Ae. aegypti, dominant and broadly distributed. Anopheles made up another 6% of the catch with An. subpictus dominating. Barcode sequence divergence in conspecific specimens ranged from 0-2.4%, while congeneric species showed from 2.3-17.8% divergence. A global haplotype analysis of disease-vectors showed the presence of multiple haplotypes, although a single haplotype of each dengue-vector species was dominant in most countries. Geographic distribution of Ae. aegypti and Ae. albopictus showed the later species was dominant and found in both rural and urban environments. As the first DNA-based analysis of mosquitoes in Pakistan, this study has begun the construction of a barcode reference library for the mosquitoes of this region. Levels of genetic diversity varied among species. Because of its capacity to differentiate species, even those with subtle morphological differences, DNA barcoding aids accurate tracking of vector populations.

Short-range phenotypic divergence among genetically distinct parapatric populations of an Australian funnel-web spider.

PubMed

Wong, Mark K L; Woodman, James D; Rowell, David M

2017-07-01

Speciation involves divergence at genetic and phenotypic levels. Where substantial genetic differentiation exists among populations, examining variation in multiple phenotypic characters may elucidate the mechanisms by which divergence and speciation unfold. Previous work on the Australian funnel-web spider Atrax sutherlandi Gray (2010; Records of the Australian Museum 62 , 285-392; Mygalomorphae: Hexathelidae: Atracinae) has revealed a marked genetic structure along a 110-kilometer transect, with six genetically distinct, parapatric populations attributable to past glacial cycles. In the present study, we explore variation in three classes of phenotypic characters (metabolic rate, water loss, and morphological traits) within the context of this phylogeographic structuring. Variation in metabolic and water loss rates shows no detectable association with genetic structure; the little variation observed in these rates may be due to the spiders' behavioral adaptations (i.e., burrowing), which buffer the effects of climatic gradients across the landscape. However, of 17 morphological traits measured, 10 show significant variation among genetic populations, in a disjunct manner that is clearly not latitudinal. Moreover, patterns of variation observed for morphological traits serving different organismic functions (e.g., prey capture, burrowing, and locomotion) are dissimilar. In contrast, a previous study of an ecologically similar sympatric spider with little genetic structure indicated a strong latitudinal response in 10 traits over the same range. The congruence of morphological variation with deep phylogeographic structure in Tallaganda's A. sutherlandi populations, as well as the inconsistent patterns of variation across separate functional traits, suggest that the spiders are likely in early stages of speciation, with parapatric populations independently responding to local selective forces.

Correlation between morphological defects, electron beam-induced current imaging, and the electrical properties of 4H-SiC Schottky diodes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Y.; Ali, G.N.; Mikhov, M.K.

2005-01-01

Defects in SiC degrade the electrical properties and yield of devices made from this material. This article examines morphological defects in 4H-SiC and defects visible in electron beam-induced current (EBIC) images and their effects on the electrical characteristics of Schottky diodes. Optical Nomarski microscopy and atomic force microscopy were used to observe the morphological defects, which are classified into 26 types based on appearance alone. Forward and reverse current-voltage characteristics were used to extract barrier heights, ideality factors, and breakdown voltages. Barrier heights decrease about linearly with increasing ideality factor, which is explained by discrete patches of low barrier heightmore » within the main contact. Barrier height, ideality, and breakdown voltage all degrade with increasing device diameter, suggesting that discrete defects are responsible. Electroluminescence was observed under reverse bias from microplasmas associated with defects containing micropipes. EBIC measurements reveal several types of features corresponding to recombination centers. The density of dark spots observed by EBIC correlates strongly with ideality factor and barrier height. Most morphological defects do not affect the reverse characteristics when no micropipes are present, but lower the barrier height and worsen the ideality factor. However, certain multiple-tailed defects, irregularly shaped defects and triangular defects with 3C inclusions substantially degrade both breakdown voltage and barrier height, and account for most of the bad devices that do not contain micropipes. Micropipes in these wafers are also frequently found to be of Type II, which do not run parallel to the c axis.« less

Correlation Between Morphological Defects, Electron Beam Induced Current Imaging, and the Electrical Properties of 4H-SiC Schottky Diodes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang,Y.; Ali, G.; Mikhov, M.

2005-01-01

Defects in SiC degrade the electrical properties and yield of devices made from this material. This article examines morphological defects in 4H-SiC and defects visible in electron beam-induced current (EBIC) images and their effects on the electrical characteristics of Schottky diodes. Optical Nomarski microscopy and atomic force microscopy were used to observe the morphological defects, which are classified into 26 types based on appearance alone. Forward and reverse current-voltage characteristics were used to extract barrier heights, ideality factors, and breakdown voltages. Barrier heights decrease about linearly with increasing ideality factor, which is explained by discrete patches of low barrier heightmore » within the main contact. Barrier height, ideality, and breakdown voltage all degrade with increasing device diameter, suggesting that discrete defects are responsible. Electroluminescence was observed under reverse bias from microplasmas associated with defects containing micropipes. EBIC measurements reveal several types of features corresponding to recombination centers. The density of dark spots observed by EBIC correlates strongly with ideality factor and barrier height. Most morphological defects do not affect the reverse characteristics when no micropipes are present, but lower the barrier height and worsen the ideality factor. However, certain multiple-tailed defects, irregularly shaped defects and triangular defects with 3C inclusions substantially degrade both breakdown voltage and barrier height, and account for most of the bad devices that do not contain micropipes. Micropipes in these wafers are also frequently found to be of Type II, which do not run parallel to the c axis.« less

Influence of Silver and Gold Nanoparticles and Thin Layers on Charge Carrier Generation in InGaN/GaN Multiple Quantum Well Structures and Crystalline Zinc Oxide Films

NASA Astrophysics Data System (ADS)

Mezdrogina, M. M.; Vinogradov, A. Ya.; Kozhanova, Yu. V.; Levitskii, V. S.

2018-04-01

It has been shown that Ag and Au nanoparticles and thin layers influence charge carrier generation in InGaN/GaN multiple quantum well structures and crystalline ZnO films owing to the surface morphology heterogeneity of the semiconductors. When nanoparticles 10 < d < 20 nm in size are applied on InGaN/GaN multiple quantum well structures with surface morphology less nonuniform than that of ZnO films, the radiation intensity has turned out to grow considerably because of a plasmon resonance with the participation of localized plasmons. The application of Ag or Au layers on the surface of the structures strongly attenuates the radiation. When Ag and Au nanoparticles are applied on crystalline ZnO films obtained by rf magnetron sputtering, the radiation intensity in the short-wavelength part of the spectrum increases insignificantly because of their highly heterogeneous surface morphology.

Comparative limb proportions reveal differential locomotor morphofunctions of alligatoroids and crocodyloids

NASA Astrophysics Data System (ADS)

Iijima, Masaya; Kubo, Tai; Kobayashi, Yoshitsugu

2018-03-01

Although two major clades of crocodylians (Alligatoroidea and Crocodyloidea) were split during the Cretaceous period, relatively few morphological and functional differences between them have been known. In addition, interaction of multiple morphofunctional systems that differentiated their ecology has barely been assessed. In this study, we examined the limb proportions of crocodylians to infer the differences of locomotor functions between alligatoroids and crocodyloids, and tested the correlation of locomotor and feeding morphofunctions. Our analyses revealed crocodyloids including Gavialis have longer stylopodia (humerus and femur) than alligatoroids, indicating that two groups may differ in locomotor functions. Fossil evidence suggested that alligatoroids have retained short stylopodia since the early stage of their evolution. Furthermore, rostral shape, an indicator of trophic function, is correlated with limb proportions, where slender-snouted piscivorous taxa have relatively long stylopodia and short overall limbs. In combination, trophic and locomotor functions might differently delimit the ecological opportunity of alligatoroids and crocodyloids in the evolution of crocodylians.

Light-induced c-Fos expression in the mouse suprachiasmatic nucleus: immunoelectron microscopy reveals co-localization in multiple cell types.

PubMed

Castel, M; Belenky, M; Cohen, S; Wagner, S; Schwartz, W J

1997-09-01

Although light is known to regulate the level of c-fos gene expression in the suprachiasmatic nucleus (SCN), the site of an endogenous circadian clock, little is known about the identities of the photically activated cells. We used light-microscopic immunocytochemistry and immunoelectron microscopy to detect c-Fos protein in the SCN of Sabra mice exposed to brief nocturnal light pulses at zeitgeber time 15-16. Stimulation with light pulses that saturated the phase-shifting response of the circadian locomotor rhythm revealed an upper limit to the number of photo-inducible c-Fos cells at about one-fifth of the estimated total SCN cell population. This functionally defined set was morphologically and phenotypically heterogeneous. About 24% could be labelled for vasoactive intestinal polypeptide, 13% for vasopressin-neurophysin, and 7% for glial fibrillary acidic protein. The remaining 56% of c-Fos-positive cells were largely of unknown phenotype, although many were presumptive interneurons, some of which were immunoreactive for nitric oxide synthase.

Digital Compositing Techniques for Coronal Imaging (Invited review)

NASA Astrophysics Data System (ADS)

Espenak, F.

2000-04-01

The solar corona exhibits a huge range in brightness which cannot be captured in any single photographic exposure. Short exposures show the bright inner corona and prominences, while long exposures reveal faint details in equatorial streamers and polar brushes. For many years, radial gradient filters and other analog techniques have been used to compress the corona's dynamic range in order to study its morphology. Such techniques demand perfect pointing and tracking during the eclipse, and can be difficult to calibrate. In the past decade, the speed, memory and hard disk capacity of personal computers have rapidly increased as prices continue to drop. It is now possible to perform sophisticated image processing of eclipse photographs on commercially available CPU's. Software programs such as Adobe Photoshop permit combining multiple eclipse photographs into a composite image which compresses the corona's dynamic range and can reveal subtle features and structures. Algorithms and digital techniques used for processing 1998 eclipse photographs will be discussed which are equally applicable to the recent eclipse of 1999 August 11.

Genomic and transcriptomic analysis of NDM-1 Klebsiella pneumoniae in spaceflight reveal mechanisms underlying environmental adaptability

PubMed Central

Li, Jia; Liu, Fei; Wang, Qi; Ge, Pupu; Woo, Patrick C. Y.; Yan, Jinghua; Zhao, Yanlin; Gao, George F.; Liu, Cui Hua; Liu, Changting

2014-01-01

The emergence and rapid spread of New Delhi Metallo-beta-lactamase-1 (NDM-1)-producing Klebsiella pneumoniae strains has caused a great concern worldwide. To better understand the mechanisms underlying environmental adaptation of those highly drug-resistant K. pneumoniae strains, we took advantage of the China's Shenzhou 10 spacecraft mission to conduct comparative genomic and transcriptomic analysis of a NDM-1 K. pneumoniae strain (ATCC BAA-2146) being cultivated under different conditions. The samples were recovered from semisolid medium placed on the ground (D strain), in simulated space condition (M strain), or in Shenzhou 10 spacecraft (T strain) for analysis. Our data revealed multiple variations underlying pathogen adaptation into different environments in terms of changes in morphology, H2O2 tolerance and biofilm formation ability, genomic stability and regulation of metabolic pathways. Additionally, we found a few non-coding RNAs to be differentially regulated. The results are helpful for better understanding the adaptive mechanisms of drug-resistant bacterial pathogens. PMID:25163721

Description of Phytomonas oxycareni n. sp. from the Salivary Glands of Oxycarenus lavaterae.

PubMed

Seward, Emily A; Votýpka, Jan; Kment, Petr; Lukeš, Julius; Kelly, Steven

2017-02-01

Phytomonas spp. (phytomonads) are a diverse and globally distributed group of unicellular eukaryotes that parasitize a wide range of plants and are transmitted by insect hosts. Here we report the discovery and characterisation of a new species of Phytomonas, named Phytomonas oxycareni n. sp., which was obtained from the salivary glands of the invasive species of true bug Oxycarenus lavaterae (Heteroptera). The new Phytomonas species exhibits a long slender promastigote morphology and can be found both within the lumen of the insect host's salivary glands as well as within the cells of the salivary gland itself. Sampling multiple individuals from the same population post-winter hibernation on two consecutive years revealed that infection was persistent over time. Finally, phylogenetic analyses of small subunit ribosomal RNA genes revealed that this species is sister to other species within the genus Phytomonas, providing new insight into the evolutionary history of the clade. Copyright © 2016 Elsevier GmbH. All rights reserved.

Three Dimensional Mesoscale Analysis of Translamellar Cross-Bridge Morphologies in the Annulus Fibrosus using Optical Coherence Tomography

PubMed Central

Han, Sang Kuy; Chen, Chao-Wei; Wierwille, Jerry; Chen, Yu; Hsieh, Adam H.

2014-01-01

The defining characteristic of the annulus fibrosus (AF) of the intervertebral disc (IVD) has long been the lamellar structures that consist of highly ordered collagen fibers arranged in alternating oblique angles from one layer to the next. However, a series of recent histologic studies have demonstrated that AF lamellae contain elastin- and type VI collagen-rich secondary “cross-bridge” structures across lamellae. In this study, we use optical coherence tomography (OCT) to elucidate the three-dimensional (3D) morphologies of these translamellar cross-bridge in AF tissues. Mesoscale volumetric images by OCT reveal a highly heterogeneous spatial network and distribution of 3-D translamellar cross-bridges. The results of this study confirm the translamellar cross-bridge is identified as a distinguishable structure, which is laid in the interbundle space of adjacent lamellae and crisscrosses multiple lamellae in the radial direction. In contrast to previously proposed models extrapolated from 2-D sections, results from this current study show that translamellar cross-bridges exist as a complex, interconnected network. We also found much greater variation in lengths of cross-bridges within the interbundle space of lamellae (0.8-1.4 mm from the current study versus 0.3-0.6 mm from 2-D sections). OCT-based 3-D morphology of translamellar cross-bridge provides novel insight into the AF structure. PMID:25564974

Morphological and Electrochemical Characterization of Nanostructured Li 4Ti 5O 12 Electrodes Using Multiple Imaging Mode Synchrotron X-ray Computed Tomography

DOE PAGES

Kashkooli, Ali Ghorbani; Foreman, Evan; Farhad, Siamak; ...

2017-09-21

In this study, synchrotron X-ray computed tomography has been utilized using two different imaging modes, absorption and Zernike phase contrast, to reconstruct the real three-dimensional (3D) morphology of nanostructured Li 4Ti 5O 12 (LTO) electrodes. The morphology of the high atomic number active material has been obtained using the absorption contrast mode, whereas the percolated solid network composed of active material and carbon-doped polymer binder domain (CBD) has been obtained using the Zernike phase contrast mode. The 3D absorption contrast image revealed that some LTO nano-particles tend to agglomerate and form secondary micro-sized particles with varying degrees of sphericity. Themore » tortuosity of electrode’s pore and solid phases were found to have directional dependence, different from Bruggeman’s tortuosity commonly used in macro-homogeneous models. The electrode’s heterogeneous structure was investigated by developing a numerical model to simulate galvanostatic discharge process using the Zernike phase contrast mode. The inclusion of CBD in the Zernike phase contrast results in an integrated percolated network of active material and CBD that is highly suited for continuum modeling. As a result, the simulation results highlight the importance of using the real 3D geometry since the spatial distribution of physical and electrochemical properties have a strong non-uniformity due to microstructural heterogeneities.« less

Monilinia Species Causing Brown Rot of Peach in China

PubMed Central

Hu, Meng-Jun; Cox, Kerik D.; Schnabel, Guido; Luo, Chao-Xi

2011-01-01

In this study, 145 peaches and nectarines displaying typical brown rot symptoms were collected from multiple provinces in China. A subsample of 26 single-spore isolates were characterized phylogenetically and morphologically to ascertain species. Phylogenetic analysis of internal transcribed spacer (ITS) regions 1 and 2, glyceraldehyde-3-phosphate dehydrogenase (G3PDH), β-tubulin (TUB2) revealed the presence of three distinct Monilinia species. These species included Monilinia fructicola, Monilia mumecola, and a previously undescribed species designated Monilia yunnanensis sp. nov. While M. fructicola is a well-documented pathogen of Prunus persica in China, M. mumecola had primarily only been isolated from mume fruit in Japan. Koch's postulates for M. mumecola and M. yunnanensis were fulfilled confirming pathogenicity of the two species on peach. Phylogenetic analysis of ITS, G3PDH, and TUB2 sequences indicated that M. yunnanensis is most closely related to M. fructigena, a species widely prevalent in Europe. Interestingly, there were considerable differences in the exon/intron structure of the cytochrome b (Cyt b) gene between the two species. Morphological characteristics, including spore size, colony morphology, lesion growth rate, and sporulation, support the phylogenetic evidence suggesting the designation of M. yunnanensis as a new species. A new multiplex PCR method was developed to facilitate the detection of M. yunnanensis and differentiation of Monilinia spp. causing brown rot of peach in China. PMID:21980371

Evolutionary Pathways for Asteroid Satellites

NASA Astrophysics Data System (ADS)

Jacobson, Seth Andrew

2015-08-01

The YORP-induced rotational fission hypothesis is a proposed mechanism for the creation of small asteroid binaries, which make up approximately 1/6-th of the near-Earth asteroid and small Main Belt asteroid populations. The YORP effect is a radiative torque that rotationally accelerates asteroids on timescales of thousands to millions of years. As asteroids rotationally accelerate, centrifugal accelerations on material within the body can match gravitational accelerations holding that material in place. When this occurs, that material goes into orbit. Once in orbit that material coalesces into a companion that undergoes continued dynamical evolution.Observations with radar, photometric and direct imaging techniques reveal a diverse array of small asteroid satellites. These systems can be sorted into a number of morphologies according to size, multiplicity of members, dynamical orbit and spin states, and member shapes. For instance, singly synchronous binaries have short separation distances between the two members, rapidly rotating oblate primary members, and tidally locked prolate secondary members. Other confirmed binary morphologies include doubly synchronous, tight asynchronous and wide asynchronous binaries. Related to these binary morphologies are unbound paired asteroid systems and bi-lobate contact binaries.A critical test for the YORP-induced rotational fission hypothesis is whether the binary asteroids produced evolve to the observed binary and related systems. In this talk I will review how this evolution is believed to occur according to gravitational dynamics, mutual body tides and the binary YORP effect.

Comparative functional analyses of ultrabithorax reveal multiple steps and paths to diversification of legs in the adaptive radiation of semi-aquatic insects.

PubMed

Khila, Abderrahman; Abouheif, Ehab; Rowe, Locke

2014-08-01

Invasion of new ecological habitats is often associated with lineage diversification, yet the genetic changes underlying invasions and radiations are poorly understood. Over 200 million years ago, the semi-aquatic insects invaded water surface from a common terrestrial ancestor and diversified to exploit a wide array of niches. Here, we uncover the changes in regulation and function of the gene Ultrabithorax associated with both the invasion of water surface and the subsequent diversification of the group. In the common ancestor of the semi-aquatic insects, a novel deployment of Ubx protein in the mid-legs increased their length, thereby enhancing their role in water surface walking. In derived lineages that specialize in rowing on the open water, additional changes in the timing of Ubx expression further elongated the mid-legs thereby facilitating their function as oars. In addition, Ubx protein function was selectively reversed to shorten specific rear-leg segments, thereby enabling their function as rudders. These changes in Ubx have generated distinct niche-specialized morphologies that account for the remarkable diversification of the semi-aquatic insects. Therefore, changes in the regulation and function of a key developmental gene may facilitate both the morphological change necessary to transition to novel habitats and fuel subsequent morphological diversification. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

Systemic adenovirus infection in Bearded Dragons (Pogona vitticeps): histological, ultrastructural and molecular findings.

PubMed

Moormann, S; Seehusen, F; Reckling, D; Kilwinski, J; Puff, C; Elhensheri, M; Wohlsein, P; Peters, M

2009-07-01

Three Inland Bearded Dragons (Pogona vitticeps) from two breeding groups were humanely destroyed following a period of anorexia. Two of the animals were 8-months old and related and one animal was approximately 2-weeks old. Necropsy examination revealed poor bodily condition but no other gross abnormalities. Microscopically there was non-suppurative hepatitis and interstitial nephritis. Multiple large, amphophilic, intranuclear inclusion bodies were present within hepatocytes and epithelial cells of the bile ducts, renal tubules, small and large intestinal mucosa, pancreatic acini and oral mucous membranes. Transmission electron microscopy (TEM) demonstrated that the inclusions comprised viral particles with morphology consistent with an adenovirus. A fragment of the adenoviral polymerase gene was amplified, sequenced and compared with other reptilian adenoviral sequences.

Multiple Polyploidization Events across Asteraceae with Two Nested Events in the Early History Revealed by Nuclear Phylogenomics

PubMed Central

Huang, Chien-Hsun; Zhang, Caifei; Liu, Mian; Hu, Yi; Gao, Tiangang; Qi, Ji; Ma, Hong

2016-01-01

Biodiversity results from multiple evolutionary mechanisms, including genetic variation and natural selection. Whole-genome duplications (WGDs), or polyploidizations, provide opportunities for large-scale genetic modifications. Many evolutionarily successful lineages, including angiosperms and vertebrates, are ancient polyploids, suggesting that WGDs are a driving force in evolution. However, this hypothesis is challenged by the observed lower speciation and higher extinction rates of recently formed polyploids than diploids. Asteraceae includes about 10% of angiosperm species, is thus undoubtedly one of the most successful lineages and paleopolyploidization was suggested early in this family using a small number of datasets. Here, we used genes from 64 new transcriptome datasets and others to reconstruct a robust Asteraceae phylogeny, covering 73 species from 18 tribes in six subfamilies. We estimated their divergence times and further identified multiple potential ancient WGDs within several tribes and shared by the Heliantheae alliance, core Asteraceae (Asteroideae–Mutisioideae), and also with the sister family Calyceraceae. For two of the WGD events, there were subsequent great increases in biodiversity; the older one proceeded the divergence of at least 10 subfamilies within 10 My, with great variation in morphology and physiology, whereas the other was followed by extremely high species richness in the Heliantheae alliance clade. Our results provide different evidence for several WGDs in Asteraceae and reveal distinct association among WGD events, dramatic changes in environment and species radiations, providing a possible scenario for polyploids to overcome the disadvantages of WGDs and to evolve into lineages with high biodiversity. PMID:27604225

Morphological Decomposition in Reading Hebrew Homographs

ERIC Educational Resources Information Center

Miller, Paul; Liran-Hazan, Batel; Vaknin, Vered

2016-01-01

The present work investigates whether and how morphological decomposition processes bias the reading of Hebrew heterophonic homographs, i.e., unique orthographic patterns that are associated with two separate phonological, semantic entities depicted by means of two morphological structures (linear and nonlinear). In order to reveal the nature of…

SIMULATING SUB-DECADAL CHANNEL MORPHOLOGIC CHANGE IN EPHEMERAL STREAM NETWORKS

EPA Science Inventory

A distributed watershed model was modified to simulate cumulative channel morphologic
change from multiple runoff events in ephemeral stream networks. The model incorporates the general design of the event-based Kinematic Runoff and" Erosion Model (KINEROS), which describes t...

Inverse modelling of fluvial sediment connectivity identifies characteristics and spatial distribution of sediment sources in a large river network.

NASA Astrophysics Data System (ADS)

Schmitt, R. J. P.; Bizzi, S.; Kondolf, G. M.; Rubin, Z.; Castelletti, A.

2016-12-01

Field and laboratory evidence indicates that the spatial distribution of transport in both alluvial and bedrock rivers is an adaptation to sediment supply. Sediment supply, in turn, depends on spatial distribution and properties (e.g., grain sizes and supply rates) of individual sediment sources. Analyzing the distribution of transport capacity in a river network could hence clarify the spatial distribution and properties of sediment sources. Yet, challenges include a) identifying magnitude and spatial distribution of transport capacity for each of multiple grain sizes being simultaneously transported, and b) estimating source grain sizes and supply rates, both at network scales. Herein, we approach the problem of identifying the spatial distribution of sediment sources and the resulting network sediment fluxes in a major, poorly monitored tributary (80,000 km2) of the Mekong. Therefore, we apply the CASCADE modeling framework (Schmitt et al. (2016)). CASCADE calculates transport capacities and sediment fluxes for multiple grainsizes on the network scale based on remotely-sensed morphology and modelled hydrology. CASCADE is run in an inverse Monte Carlo approach for 7500 random initializations of source grain sizes. In all runs, supply of each source is inferred from the minimum downstream transport capacity for the source grain size. Results for each realization are compared to sparse available sedimentary records. Only 1 % of initializations reproduced the sedimentary record. Results for these realizations revealed a spatial pattern in source supply rates, grain sizes, and network sediment fluxes that correlated well with map-derived patterns in lithology and river-morphology. Hence, we propose that observable river hydro-morphology contains information on upstream source properties that can be back-calculated using an inverse modeling approach. Such an approach could be coupled to more detailed models of hillslope processes in future to derive integrated models of hillslope production and fluvial transport processes, which is particularly useful to identify sediment provenance in poorly monitored river basins.

Two stable variants of Burkholderia pseudomallei strain MSHR5848 express broadly divergent in vitro phenotypes associated with their virulence differences.

PubMed

Shea, A A; Bernhards, R C; Cote, C K; Chase, C J; Koehler, J W; Klimko, C P; Ladner, J T; Rozak, D A; Wolcott, M J; Fetterer, D P; Kern, S J; Koroleva, G I; Lovett, S P; Palacios, G F; Toothman, R G; Bozue, J A; Worsham, P L; Welkos, S L

2017-01-01

Burkholderia pseudomallei (Bp), the agent of melioidosis, causes disease ranging from acute and rapidly fatal to protracted and chronic. Bp is highly infectious by aerosol, can cause severe disease with nonspecific symptoms, and is naturally resistant to multiple antibiotics. However, no vaccine exists. Unlike many Bp strains, which exhibit random variability in traits such as colony morphology, Bp strain MSHR5848 exhibited two distinct and relatively stable colony morphologies on sheep blood agar plates: a smooth, glossy, pale yellow colony and a flat, rough, white colony. Passage of the two variants, designated "Smooth" and "Rough", under standard laboratory conditions produced cultures composed of > 99.9% of the single corresponding type; however, both could switch to the other type at different frequencies when incubated in certain nutritionally stringent or stressful growth conditions. These MSHR5848 derivatives were extensively characterized to identify variant-associated differences. Microscopic and colony morphology differences on six differential media were observed and only the Rough variant metabolized sugars in selective agar. Antimicrobial susceptibilities and lipopolysaccharide (LPS) features were characterized and phenotype microarray profiles revealed distinct metabolic and susceptibility disparities between the variants. Results using the phenotype microarray system narrowed the 1,920 substrates to a subset which differentiated the two variants. Smooth grew more rapidly in vitro than Rough, yet the latter exhibited a nearly 10-fold lower lethal dose for mice than Smooth. Finally, the Smooth variant was phagocytosed and replicated to a greater extent and was more cytotoxic than Rough in macrophages. In contrast, multiple locus sequence type (MLST) analysis, ribotyping, and whole genome sequence analysis demonstrated the variants' genetic conservation; only a single consistent genetic difference between the two was identified for further study. These distinct differences shown by two variants of a Bp strain will be leveraged to better understand the mechanism of Bp phenotypic variability and to possibly identify in vitro markers of infection.

The role of phonology, morphology, and orthography in English and Russian spelling.

PubMed

Boulware-Gooden, Regina; Joshi, R Malatesha; Grigorenko, Elena

2015-05-01

The purpose of the present study was to explore the role of phonology, morphology and orthography in predicting the spelling performance in English-speaking and Russian-speaking children. Tests that tap phonology, morphology and orthography were administered to students in grades 4 and 6 in the USA and Russia. Multiple regression analyses showed that phonology and morphology contributed more for spelling of English words while orthography and morphology contributed more to the spelling of Russian words. The results are explained in terms of the orthographic nature of English and Russian languages as well as the instructional practices and the importance of morphology in spelling in both the languages. Copyright © 2015 John Wiley & Sons, Ltd.

The Relation of Morphological Awareness and Syntactic Awareness to Adults' Reading Comprehension: Is Vocabulary Knowledge a Mediating Variable?

ERIC Educational Resources Information Center

Guo, Ying; Roehrig, Alysia D.; Williams, Rihana S.

2011-01-01

The authors' goal was to examine the structural relationships among vocabulary knowledge, morphological awareness, syntactic awareness, and reading comprehension in English-speaking adults. Structural equation analysis of data collected from 151 participants revealed that morphological awareness affected reading comprehension directly. Syntactic…

First record of myxozoan parasites from fresh water fishes of Jammu and Kashmir and their pathogenecity.

PubMed

Dar, Shoaib Ali; Kaur, Harpreet; Chishti, M Z

2017-04-01

The present study was aimed to isolate myxozoan parasites infecting the native carp Schizothorax esocinus (Heckel) and pond reared carp Labeo rohita (Ham.) collected from fresh water ecosystems of Jammu and Kashmir from July 2013 to June 2014. Various organs such as eyes, gills, scales, fins, intestines, visceral organs and pericardial cavity of as many as 100 live specimens were examined. Results revealed that 14% of the examined L. rohita were infected with Myxobolus rocatlae (Ham.) and 6% of S. esocinus (Heckel) were infected with M. kashmirensis sp. nov. Clinical signs revealed mucous laden gills while the parasitological observation under stereozoom binocular microscope revealed multiple minute plasmodia on the gills. On rupturing these plasmodia with sharp needle 100-500 myxospores were liberated. The identification to species level was done on the basis of morphological and morphometric attributes of the myxospores. This is the first record of myxozoan parasites in fishes from the state of Jammu and Kashmir, India. Histological observations of infected gills revealed plasmodia of two types (LV 4 intralamellar vascular type) in M. rocatlae and (LV 3 intralamellar vascular type) in M. kasmirensis causing necrosis, hyperplasia, hypertrophy and vacuolization of the epithelial and vascular endothelium. Copyright © 2017 Elsevier Ltd. All rights reserved.

Lexicality, morphological structure, and semantic transparency in the processing of German ver-verbs: The complementarity of on-line and off-line evidence.

PubMed

Schirmeier, Matthias K; Derwing, Bruce L; Libben, Gary

2004-01-01

Two types of experiments investigate the visual on-line and off-line processing of German ver-verbs (e.g., verbittern 'to embitter'). In Experiments 1 and 2 (morphological priming), latency patterns revealed the existence of facilitation effects for the morphological conditions (BITTER-VERBITTERN and BITTERN-VERBITTERN) as compared to the neutral conditions (SAUBER-VERBITTERN and SAUBERN-VERBITTERN). In Experiments 3 and 4 (rating tasks) participants had to judge whether the target (VERBITTERN) "comes from," "contains a form of," or "contains the meaning of" the root (BITTER) or the root+en substring (BITTERN). Taken together, these studies revealed the combined influence of the three factors of lexicality (real word status), morphological structure, and semantic transparency.

Hybridization and restricted gene flow between native and introduced stocks of Alpine whitefish (Coregonus sp.) across multiple environments

PubMed Central

Winkler, Kathrin A; Pamminger-Lahnsteiner, Barbara; Wanzenböck, Josef; Weiss, Steven

2011-01-01

Translocations of Baltic whitefish (Coregonus sp.) into Austrian Alpine lakes have created ‘artificial hybrid zones’, threatening the genetic integrity of native lineages. We evaluate the genetic structure of Coregonus in Austrian lakes and characterize hybridization and introgression between native and introduced lineages. Fifteen populations (N= 747) were assessed for allelic variation at eight microsatellite loci and a reduced set (N= 253) for variation across two mtDNA genes (cyt b and NADH-3). Bayesian approaches were used to estimate individual admixture proportions (q-values) and classify genotypes as native, introduced or hybrids. q-value distributions varied among populations highlighting differential hybridization and introgression histories. Many lakes revealed a clear distinction between native and introduced genotypes despite hybridization, whereas some locations revealed hybrid swarms. Genetic structure among lakes was congruent with morphological divergence and novelty raising speculation of multiple taxa, including a population south of the Alps, outside the putative native range of Coregonus. Although statistically congruent with inferences based on nuclear markers, mitochondrial haplotype data was not diagnostic with respect to native and non-native lineages, supporting that the Alpine region was colonized post-glacially by an admixture of mtDNA lineages, which coalesce >1 Ma. Mechanisms promoting or eroding lineage isolation are discussed, as well as a high potential to conserve native Alpine lineages despite the extensive historical use of introduced Baltic stocks. PMID:21199024

Myeloid transformation of plasma cell myeloma: molecular evidence of clonal evolution revealed by next generation sequencing.

PubMed

Gralewski, Jonathon H; Post, Ginell R; van Rhee, Frits; Yuan, Youzhong

2018-02-20

Plasma cell myeloma (PCM) is a neoplasm of terminally differentiated B lymphocytes with molecular heterogeneity. Although therapy-related myeloid neoplasms are common in plasma cell myeloma patients after chemotherapy, transdifferentiation of plasma cell myeloma into myeloid neoplasms has not been reported in literature. Here we report a very rare case of myeloid neoplasm transformed from plasma cell myeloma. A 60-year-old man with a history of plasma cell myeloma with IGH-MAF gene rearrangement and RAS/RAF mutations developed multiple soft tissue lesions one year following melphalan-based chemotherapy and autologous stem cell transplant. Morphological and immunohistochemical characterization of the extramedullary disease demonstrated that the tumor cells were derived from the monocyte-macrophage lineage. Next generation sequencing (NGS) studies detected similar clonal aberrations in the diagnostic plasma cell population and post-therapy neoplastic cells, including IGH-MAF rearrangement, multiple genetic mutations in RAS signaling pathway proteins, and loss of tumor suppressor genes. Molecular genetic analysis also revealed unique genomic alterations in the transformed tumor cells, including gain of NF1 and loss of TRAF3. To our knowledge, this is the first case of myeloid sarcoma transdifferentiated from plasma cell neoplasm. Our findings in this unique case suggest clonal evolution of plasma cell myeloma to myeloma neoplasm and the potential roles of abnormal RAS/RAF signaling pathway in lineage switch or transdifferentiation.

Proteometabolomic response of Deinococcus radiodurans exposed to UVC and vacuum conditions: Initial studies prior to the Tanpopo space mission.

PubMed

Ott, Emanuel; Kawaguchi, Yuko; Kölbl, Denise; Chaturvedi, Palak; Nakagawa, Kazumichi; Yamagishi, Akihiko; Weckwerth, Wolfram; Milojevic, Tetyana

2017-01-01

The multiple extremes resistant bacterium Deinococcus radiodurans is able to withstand harsh conditions of simulated outer space environment. The Tanpopo orbital mission performs a long-term space exposure of D. radiodurans aiming to investigate the possibility of interplanetary transfer of life. The revealing of molecular machinery responsible for survivability of D. radiodurans in the outer space environment can improve our understanding of underlying stress response mechanisms. In this paper, we have evaluated the molecular response of D. radiodurans after the exposure to space-related conditions of UVC irradiation and vacuum. Notably, scanning electron microscopy investigations showed that neither morphology nor cellular integrity of irradiated cells was affected, while integrated proteomic and metabolomic analysis revealed numerous molecular alterations in metabolic and stress response pathways. Several molecular key mechanisms of D. radiodurans, including the tricarboxylic acid cycle, the DNA damage response systems, ROS scavenging systems and transcriptional regulators responded in order to cope with the stressful situation caused by UVC irradiation under vacuum conditions. These results reveal the effectiveness of the integrative proteometabolomic approach as a tool in molecular analysis of microbial stress response caused by space-related factors.

Proteometabolomic response of Deinococcus radiodurans exposed to UVC and vacuum conditions: Initial studies prior to the Tanpopo space mission

PubMed Central

Ott, Emanuel; Kawaguchi, Yuko; Kölbl, Denise; Chaturvedi, Palak; Nakagawa, Kazumichi; Yamagishi, Akihiko; Weckwerth, Wolfram

2017-01-01

The multiple extremes resistant bacterium Deinococcus radiodurans is able to withstand harsh conditions of simulated outer space environment. The Tanpopo orbital mission performs a long-term space exposure of D. radiodurans aiming to investigate the possibility of interplanetary transfer of life. The revealing of molecular machinery responsible for survivability of D. radiodurans in the outer space environment can improve our understanding of underlying stress response mechanisms. In this paper, we have evaluated the molecular response of D. radiodurans after the exposure to space-related conditions of UVC irradiation and vacuum. Notably, scanning electron microscopy investigations showed that neither morphology nor cellular integrity of irradiated cells was affected, while integrated proteomic and metabolomic analysis revealed numerous molecular alterations in metabolic and stress response pathways. Several molecular key mechanisms of D. radiodurans, including the tricarboxylic acid cycle, the DNA damage response systems, ROS scavenging systems and transcriptional regulators responded in order to cope with the stressful situation caused by UVC irradiation under vacuum conditions. These results reveal the effectiveness of the integrative proteometabolomic approach as a tool in molecular analysis of microbial stress response caused by space-related factors. PMID:29244852

Morphological, molecular and biological evidence reveal two cryptic species in Mecinus janthinus Germar (Coleoptera, Curculionidae), a successful biological control agent of Dalmatian toadflax, Linaria dalmatica (Lamiales, Plantaginaceae)

Treesearch

Ivo Tosevski; Roberto Caldara; Jelena Jovic; Gerardo Hernandez-Vera; Cosimo Baviera; Andre Gassmann; Brent C. Emerson

2011-01-01

A combined morphological, molecular and biological study shows that the weevil species presently named Mecinus janthinus is actually composed of two different cryptic species: M. janthinus Germar, 1821 and M. janthiniformis Tosevski & Caldara sp.n. These species are morphologically distinguishable from each other by a few very subtle morphological characters. On...

Morphological and molecular characteristics of Sarcocystis bertrami from horses and donkeys in China

USDA-ARS?s Scientific Manuscript database

Sarcocystis cysts collected from donkeys and horses were studied by morphological and molecular methods. Morphological studies performed by light microscopy (LM) revealed that each of two types of cysts were present in samples from both donkey and horse. These two types of cysts, type I (larger) and...

Functional Zoning and Urban Development Tendencies of Bucharest City/Romania

NASA Astrophysics Data System (ADS)

Armas, Iuliana; Dumitrascu, Silvia

2010-05-01

Any form of urban development policy for environmental management should be based on the differentiation of the structure of a territory that can be found in the shape of functional zoning. Identifying the patterns of morphological structure of the urban space can provide essential clues concerning the proper measures to take into consideration during the activity of urban planning. In this sense, the Bucharest municipality study case provides the example of a dynamic urban space with a complex and distinctive evolutionary structure. The aim of the study is to set out the main events that shaped the Bucharest city space and the patterns resulted from their impact at the functional level of the Romanian capital. In order to identify the development tendencies of the Bucharest municipality, a series of aspects concerning urban morphology should be highlighted that reveal the impact of the socio-economical policies at the structural level of the territory. In this sense, three images of the urban space stand out, representative for the period when they materialized: the Post-Byzantine (XV-XVIII), the Fanariot (XVIII) and the Modern periods (XIX-XX). The corresponding cartographic documents analyzed are: the Franz Purcel Plan (dated 1789), the Romanian Guide Print Plan and, respectively, the AGC Busman Print Plan. The analysis reveals three distinctive morphological types: radial-concentric in the 17th century, polynuclear in the 18th century, leading to the mixed character in the Modern period. The latest trait of the urban territory is based on the concentric character of the street network (three circles were identified at the level of the capital city that point out the evolution of the urban space: Dacia bv-Mircea Vulcanescu, Stefan cel Mare bv-Iancu de Hunedoara and the last circle outlined by the ring road) and the presence of multiple nuclei that accumulate the commercial, administrative and business functions of the city.

On the origins of Balkan endemics: the complex evolutionary history of the Cyanus napulifer group (Asteraceae).

PubMed

Olšavská, Katarína; Slovák, Marek; Marhold, Karol; Štubňová, Eliška; Kučera, Jaromír

2016-11-01

The Balkan Peninsula is one of the most important centres of plant diversity in Europe. Here we aim to fill the gap in the current knowledge of the evolutionary processes and factors modelling this astonishing biological richness by applying multiple approaches to the Cyanus napulifer group. To reconstruct the mode of diversification within the C. napulifer group and to uncover its relationships with potential relatives with x = 10 from Europe and Northern Africa, we examined variation in genetic markers (amplified fragment length polymorphisms [AFLPs]; 460 individuals), relative DNA content (4',6-diamidino-2-phenylindole [DAPI] flow cytometry, 330 individuals) and morphology (multivariate morphometrics, 40 morphological characters, 710 individuals). To elucidate its evolutionary history, we analysed chloroplast DNA (cpDNA) sequences of the genus Cyanus deposited in the GenBank database. The AFLPs revealed a suite of closely related entities with variable levels of differentiation. The C. napulifer group formed a genetically well-defined unit. Samples outside the group formed strongly diversified and mostly species-specific genetic lineages with no further geographical patterns, often characterized also by a different DNA content. AFLP analysis of the C. napulifer group revealed extensive radiation and split it into nine allopatric (sub)lineages with varying degrees of congruence among genetic, DNA-content and morphological patterns. Genetic admixture was usually detected in contact zones between genetic lineages. Plastid data indicated extensive maintenance of ancestral variation across Cyanus perennials. The C. napulifer group is an example of a rapidly and recently diversified plant group whose genetic lineages have evolved in spatio-temporal isolation on the topographically complex Balkan Peninsula. Adaptive radiation, accompanied in some cases by long-term isolation and hybridization, has contributed to the formation of this species complex and its mosaic pattern. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The Evolution of Morphospace in Phytophagous Scarab Chafers: No Competition - No Divergence?

PubMed Central

Eberle, Jonas; Myburgh, Renier; Ahrens, Dirk

2014-01-01

Body shape reflects species' evolution and mediates its role in the environment as it integrates gene expression, life style, and structural morphology. Its comparative analysis may reveal insight on what shapes shape, being a useful approach when other evidence is lacking. Here we investigated evolutionary patterns of body shape in the highly diverse phytophagous chafers (Scarabaeidae: Pleurosticti), a polyphagous group utilizing different parts of angiosperms. Because the reasons of their successful diversification are largely unknown, we used a phylogenetic tree and multivariate analysis on twenty linear measurements of body morphology including all major Pleurosticti lineages to infer patterns of morphospace covariation and divergence. The chafer's different feeding types resulted to be not distinguishable in the described morphospace which was largely attributed to large occupancy of the morphospace of some feeding types and to multiple convergences of feeding behavior (particularly of anthophagy). Low correlation between molecular and morphological rates of evolution, including significant rate shifts for some lineages, indicated directed selection within feeding types. This is supported by morphospace divergence within feeding types and convergent evolution in Australian Melolonthinae. Traits driving morphospace divergence were extremities and traits linked with locomotion behavior, but also body size. Being highly adaptive for burrowing and locomotion these traits showed major changes in the evolution of pleurostict scarabs. These activities also affected another trait, the metacoxal length, which is highly influenced by key innovations of the metacoxa (extended mesal process, secondary closure) particularly in one lineage, the Sericini. Significant shape divergence between major lineages and a lack of strong differentiation among closely related lineages indicated that the question about the presence or absence of competition-derived directed selection needs to be addressed for different time scales. Striking divergence between some sister lineages at their origin revealed strong driven selection towards morphospace divergence, possibly linked with resource partitioning. PMID:24875856

[A research on real-time ventricular QRS classification methods for single-chip-microcomputers].

PubMed

Peng, L; Yang, Z; Li, L; Chen, H; Chen, E; Lin, J

1997-05-01

Ventricular QRS classification is key technique of ventricular arrhythmias detection in single-chip-microcomputer based dynamic electrocardiogram real-time analyser. This paper adopts morphological feature vector including QRS amplitude, interval information to reveal QRS morphology. After studying the distribution of QRS morphology feature vector of MIT/BIH DB ventricular arrhythmia files, we use morphological feature vector cluster to classify multi-morphology QRS. Based on the method, morphological feature parameters changing method which is suitable to catch occasional ventricular arrhythmias is presented. Clinical experiments verify missed ventricular arrhythmia is less than 1% by this method.

Magnetic fields in multiple bright-rimmed clouds in different directions of H II region IC 1396

NASA Astrophysics Data System (ADS)

Soam, Archana; Maheswar, G.; Lee, Chang Won; Neha, S.; Kim, Kee-Tae

2018-06-01

Bright-rimmed clouds (BRCs) form on the edges of H II regions affected by high-energy radiation from a central ionizing source. The UV radiation from the ionizing source results in compression and ionization, causing either cloud disruption or further star formation. In this work, we present R-band polarization measurements towards four BRCs, namely IC 1396A, BRC 37, BRC 38 and BRC 39, located in different directions in the H II region, Sh2-131, in order to map the magnetic field (B-field) in the plane of the sky. These BRCs are illuminated by the O star HD 206267 and present a range of projected on-sky geometries. This provides an opportunity to gain an understanding of the magnetized evolution of BRCs. The B-field geometries of the clouds deduced from the polarization data, after correction for foreground contamination by the interstellar medium, are seen to be connected to the ambient B-fields on large scales. They seem to play an important role in shaping the clouds IC 1396A and BRC 37. BRCs 38 and 39 show a broader and snubber head morphology, possibly because the B-fields are aligned with incoming radiation, as revealed in the simulations. A good general agreement is noted on comparing our observational results with the simulations, supporting the importance of B-fields in BRC evolution. This work is the first step towards systematic mapping the B-fields morphology in multiple BRCs in an expanding H II region, extending our previous work.

A systematic screen for morphological abnormalities during fission yeast sexual reproduction identifies a mechanism of actin aster formation for cell fusion

PubMed Central

Groux, Raphaël; Vincenzetti, Vincent

2017-01-01

In non-motile fungi, sexual reproduction relies on strong morphogenetic changes in response to pheromone signaling. We report here on a systematic screen for morphological abnormalities of the mating process in fission yeast Schizosaccharomyces pombe. We derived a homothallic (self-fertile) collection of viable deletions, which, upon visual screening, revealed a plethora of phenotypes affecting all stages of the mating process, including cell polarization, cell fusion and sporulation. Cell fusion relies on the formation of the fusion focus, an aster-like F-actin structure that is marked by strong local accumulation of the myosin V Myo52, which concentrates secretion at the fusion site. A secondary screen for fusion-defective mutants identified the myosin V Myo51-associated coiled-coil proteins Rng8 and Rng9 as critical for the coalescence of the fusion focus. Indeed, rng8Δ and rng9Δ mutant cells exhibit multiple stable dots at the cell-cell contact site, instead of the single focus observed in wildtype. Rng8 and Rng9 accumulate on the fusion focus, dependent on Myo51 and tropomyosin Cdc8. A tropomyosin mutant allele, which compromises Rng8/9 localization but not actin binding, similarly leads to multiple stable dots instead of a single focus. By contrast, myo51 deletion does not strongly affect fusion focus coalescence. We propose that focusing of the actin filaments in the fusion aster primarily relies on Rng8/9-dependent cross-linking of tropomyosin-actin filaments. PMID:28410370

Comparison of structure, morphology, and leach characteristics of multi-phase ceramics produced via melt processing and hot isostatic pressing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dandeneau, Christopher S.; Hong, Tao; Brinkman, Kyle S.

Melt processing of multi-phase ceramic waste forms offers potential advantages over traditional solid-state synthesis methods given both the prevalence of melters currently in use and the ability to reduce the possibility of airborne radionuclide contamination. In this work, multi-phase ceramics with a targeted hollandite composition of Ba 1.0Cs 0.3Cr 1.0Al 0.3Fe 1.0Ti 5.7O 16 were fabricated by melt processing at 1675 °C and hot isostatic pressing (HIP) at 1250 and 1300 °C. X-ray diffraction analysis (XRD) confirmed hollandite as the major phase in all specimens. Zirconolite/pyrochlore peaks and weaker perovskite reflections were observed after melt processing, while HIP samples displayedmore » prominent perovskite peaks and low-intensity zirconolite reflections. Melt processing produced specimens with large (>50 μm) well-defined hollandite grains, while HIP yielded samples with a more fine-grained morphology. Elemental analysis showed “islands” rich in Cs and Ti across the surface of the 1300 °C HIP sample, suggesting partial melting and partitioning of Cs into multiple phases. Photoemission data revealed multiple Cs 3d spin-orbit pairs for the HIP samples, with the lower binding energy doublets likely corresponding to Cs located in more leachable phases. Among all specimens examined, the melt-processed sample exhibited the lowest fractional release rates for Rb and Cs. However, the retention of Sr and Mo was greater in the HIP specimens.« less

Geographic variation in floral allometry suggests repeated transitions between selfing and outcrossing in a mixed mating plant.

PubMed

Summers, Holly E; Hartwick, Sally M; Raguso, Robert A

2015-05-01

Isometric and allometric scaling of a conserved floral plan could provide a parsimonious mechanism for rapid and reversible transitions between breeding systems. This scaling may occur during transitions between predominant autogamy and xenogamy, contributing to the maintenance of a stable mixed mating system. We compared nine disjunct populations of the polytypic, mixed mating species Oenothera flava (Onagraceae) to two parapatric relatives, the obligately xenogamous species O. acutissima and the mixed mating species O. triloba. We compared floral morphology of all taxa using principal component analysis (PCA) and developmental trajectories of floral organs using ANCOVA homogeneity of slopes. The PCA revealed both isometric and allometric scaling of a conserved floral plan. Three principal components (PCs) explained 92.5% of the variation in the three species. PC1 predominantly loaded on measures of floral size and accounts for 36% of the variation. PC2 accounted for 35% of the variation, predominantly in traits that influence pollinator handling. PC3 accounted for 22% of the variation, primarily in anther-stigma distance (herkogamy). During O. flava subsp. taraxacoides development, style elongation was accelerated relative to anthers, resulting in positive herkogamy. During O. flava subsp. flava development, style elongation was decelerated, resulting in zero or negative herkogamy. Of the two populations with intermediate morphology, style elongation was accelerated in one population and decelerated in the other. Isometric and allometric scaling of floral organs in North American Oenothera section Lavauxia drive variation in breeding system. Multiple developmental paths to intermediate phenotypes support the likelihood of multiple mating system transitions. © 2015 Botanical Society of America, Inc.

True morphology of mitral regurgitant flow assessed by three-dimensional transesophageal echocardiography.

PubMed

Lombardero, Martin; Henquin, Ruth; Perea, Gabriel; Corneli, Mariana; Izurieta, Carlos

2017-01-01

Quantification of mitral regurgitation (MR) by two-dimensional (2D) transthoracic echocardiography (TTE) is based on the analysis of the proximal flow convergence (PFC) and the "vena contracta" (VC). This method assumes geometries and can be misleading. In contrast, three-dimensional (3D) echocardiography directly measures flow volumes and does not assume geometries, which allows for more accurate MR evaluation. To report the 3D transesophageal echocardiography (3DTEE) feasibility for MR quantification and evaluate its concordance with 2D echo. Twenty-seven consecutive patients undergoing 2D and 3DTEE for presurgical MR evaluation were studied prospectively. MR quantification was performed by classical 2D methods based on PFC. Diameters of the VC in orthogonal planes by 3DTEE were estimated, establishing the VC sphericity index as well as VC area (VCA) by direct planimetry. In case of multiple jets, we calculated the sum of the VCA. MR assessment by 3DTEE was feasible. An adequate concordance between VC measurements by 2D methods (TTE and TEE) was observed; however, there was a poor correlation when compared with 3DTEE. The sphericity index of the VC was: 2.08 (±0. 72), reflecting a noncircular VC. 3DTEE is a feasible method for the assessment of the MR true morphology, allowing a better quantification of MR without assuming any geometry. This method revealed the presence of multiple jets, potentially improving MR evaluation and leading to changes in medical decision when compared to 2D echo assessment. © 2016, Wiley Periodicals, Inc.

Comparison of structure, morphology, and leach characteristics of multi-phase ceramics produced via melt processing and hot isostatic pressing

DOE PAGES

Dandeneau, Christopher S.; Hong, Tao; Brinkman, Kyle S.; ...

2018-02-08

Melt processing of multi-phase ceramic waste forms offers potential advantages over traditional solid-state synthesis methods given both the prevalence of melters currently in use and the ability to reduce the possibility of airborne radionuclide contamination. In this work, multi-phase ceramics with a targeted hollandite composition of Ba 1.0Cs 0.3Cr 1.0Al 0.3Fe 1.0Ti 5.7O 16 were fabricated by melt processing at 1675 °C and hot isostatic pressing (HIP) at 1250 and 1300 °C. X-ray diffraction analysis (XRD) confirmed hollandite as the major phase in all specimens. Zirconolite/pyrochlore peaks and weaker perovskite reflections were observed after melt processing, while HIP samples displayedmore » prominent perovskite peaks and low-intensity zirconolite reflections. Melt processing produced specimens with large (>50 μm) well-defined hollandite grains, while HIP yielded samples with a more fine-grained morphology. Elemental analysis showed “islands” rich in Cs and Ti across the surface of the 1300 °C HIP sample, suggesting partial melting and partitioning of Cs into multiple phases. Photoemission data revealed multiple Cs 3d spin-orbit pairs for the HIP samples, with the lower binding energy doublets likely corresponding to Cs located in more leachable phases. Among all specimens examined, the melt-processed sample exhibited the lowest fractional release rates for Rb and Cs. However, the retention of Sr and Mo was greater in the HIP specimens.« less

Numerical Simulations of Silverpit Crater Collapse

NASA Technical Reports Server (NTRS)

Collins, G. S.; Ivanov, B. A.; Turtle, E. P.; Melosh, H. J.

2003-01-01

The Silverpit crater is a recently discovered, 60-65 Myr old complex crater, which lies buried beneath the North Sea, about 150 km east of Britain. High-resolution images of Silverpit's subsurface structure, provided by three-dimensional seismic reflection data, reveal an inner-crater morphology similar to that expected for a 5-8 km diameter terrestrial crater. The crater walls show evidence of terrace-style slumping and there is a distinct central uplift, which may have produced a central peak in the pristine crater morphology. However, Silverpit is not a typical 5-km diameter terrestrial crater, because it exhibits multiple, concentric rings outside the main cavity. External concentric rings are normally associated with much larger impact structures, for example Chicxulub on Earth, or Orientale on the Moon. Furthermore, external rings associated with large impacts on the terrestrial planets and moons are widely-spaced, predominantly inwardly-facing, asymmetric scarps. However, the seismic data show that the external rings at Silverpit represent closely-spaced, concentric faultbound graben, with both inwardly and outwardly facing fault-scarps. This type of multi-ring structure directly analogous to the Valhalla-type multi-ring basins found on the icy satellites. Thus, the presence and style of the multiple rings at Silverpit is surprising given both the size of the crater and its planetary setting. A further curiosity of the Silverpit structure is that the external concentric rings appear to be extensional features on the West side of the crater and compressional features on the East side. The crater also lies in a local depression, thought to be created by postimpact movement of a salt layer buried beneath the crater.

CCR4-Not Complex Subunit Not2 Plays Critical Roles in Vegetative Growth, Conidiation and Virulence in Watermelon Fusarium Wilt Pathogen Fusarium oxysporum f. sp. niveum

PubMed Central

Dai, Yi; Cao, Zhongye; Huang, Lihong; Liu, Shixia; Shen, Zhihui; Wang, Yuyan; Wang, Hui; Zhang, Huijuan; Li, Dayong; Song, Fengming

2016-01-01

CCR4-Not complex is a multifunctional regulator that plays important roles in multiple cellular processes in eukaryotes. In the present study, the biological function of FonNot2, a core subunit of the CCR4-Not complex, was explored in Fusarium oxysporum f. sp. niveum (Fon), the causal agent of watermelon wilt disease. FonNot2 was expressed at higher levels in conidia and germinating conidia and during infection in Fon-inoculated watermelon roots than in mycelia. Targeted disruption of FonNot2 resulted in retarded vegetative growth, reduced conidia production, abnormal conidial morphology, and reduced virulence on watermelon. Scanning electron microscopy observation of infection behaviors and qRT-PCR analysis of in planta fungal growth revealed that the ΔFonNot2 mutant was defective in the ability to penetrate watermelon roots and showed reduced fungal biomass in root and stem of the inoculated plants. Phenotypic and biochemical analyses indicated that the ΔFonNot2 mutant displayed hypersensitivity to cell wall perturbing agents (e.g., Congo Red and Calcofluor White) and oxidative stress (e.g., H2O2 and paraquat), decreased fusaric acid content, and reduced reactive oxygen species (ROS) production during spore germination. Our data demonstrate that FonNot2 plays critical roles in regulating vegetable growth, conidiogenesis and conidia morphology, and virulence on watermelon via modulating cell wall integrity, oxidative stress response, ROS production and FA biosynthesis through the regulation of transcription of genes involved in multiple pathways. PMID:27695445

Changes in channel morphology over human time scales [Chapter 32

Treesearch

John M. Buffington

2012-01-01

Rivers are exposed to changing environmental conditions over multiple spatial and temporal scales, with the imposed environmental conditions and response potential of the river modulated to varying degrees by human activity and our exploitation of natural resources. Watershed features that control river morphology include topography (valley slope and channel...

Unpacking boxes: Integration of molecular, morphological and ecological approaches reveals extensive patterns of reticulate evolution in box eucalypts.

PubMed

Flores-Rentería, Lluvia; Rymer, Paul D; Riegler, Markus

2017-03-01

Reticulate evolution by hybridization is considered a common process shaping the evolution of many plant species, however, reticulation could also be due to incomplete lineage sorting in biodiverse systems. For our study we selected a group of closely related plant taxa with contrasting yet partially overlapping geographic distributions and different population sizes, to distinguish between reticulated patterns due to hybridization and incomplete lineage sorting. We predicted that sympatric or proximal populations of different species are more likely to have gene flow than geographically distant populations of the same widespread species. Furthermore, for species with restricted distributions, and therefore, small effective population sizes, we predicted complete lineage sorting. Eastern grey box eucalypt species (Eucalyptus supraspecies Moluccanae) provide an ideal system to explore patterns of reticulate evolution. They form a diverse, recently evolved and phylogenetically undefined group within Eucalyptus, with overlapping morphological features and hybridization in nature. We used a multi-faceted approach, combining analyses of chloroplast and nuclear DNA, as well as seedling morphology, flowering time and ecological spatial differentiation in order to test for species delimitation and reticulate evolution in this group. The multiple layers of results were consistent and suggested a lack of monophyly at different hierarchical levels due to multidirectional gene flow among several species, challenging species delimitation. Chloroplast and nuclear haplotypes were shared among different species in geographic proximity, consistent with hybridization zones. Furthermore, species with restricted distributions appeared better resolved due to lineage sorting in the absence of hybridization. We conclude that a combination of molecular, morphological and ecological approaches is required to disentangle patterns of reticulate evolution in the box eucalypts. Published by Elsevier Inc.

Colloidal synthesis of Cu-ZnO and Cu@CuNi-ZnO hybrid nanocrystals with controlled morphologies and multifunctional properties.

PubMed

Zeng, Deqian; Gong, Pingyun; Chen, Yuanzhi; Zhang, Qinfu; Xie, Qingshui; Peng, Dong-Liang

2016-06-02

Metal-semiconductor hybrid nanocrystals have received extensive attention owing to their multiple functionalities which can find wide technological applications. The utilization of low-cost non-noble metals to construct novel metal-semiconductor hybrid nanocrystals is important and meaningful for their large-scale applications. In this study, a facile solution approach is developed for the synthesis of Cu-ZnO hybrid nanocrystals with well-controlled morphologies, including nanomultipods, core-shell nanoparticles, nanopyramids and core-shell nanowires. In the synthetic strategy, Cu nanocrystals formed in situ serve as seeds for the heterogeneous nucleation and growth of ZnO, and it eventually forms various Cu-ZnO hetero-nanostructures under different reaction conditions. These hybrid nanocrystals possess well-defined and stable heterostructure junctions. The ultraviolet-visible-near infrared spectra reveal morphology-dependent surface plasmon resonance absorption of Cu and the band gap absorption of ZnO. Furthermore, we construct a novel Cu@CuNi-ZnO ternary hetero-nanostructure by incorporating the magnetic metal Ni into the pre-synthesized colloidal Cu nanocrystals. Such hybrid nanocrystals possess a magnetic Cu-Ni intermediate layer between the ZnO shell and the Cu core, and exhibit ferromagnetic/superparamagnetic properties which expand their functionalities. Finally, enhanced photocatalytic activities are observed in the as-prepared non-noble metal-ZnO hybrid nanocrystals. This study not only provides an economical way to prepare high-quality morphology-controlled Cu-ZnO hybrid nanocrystals for potential applications in the fields of photocatalysis and photovoltaic devices, but also opens up new opportunities in designing ternary non-noble metal-semiconductor hybrid nanocrystals with multifunctionalities.

Overexpression of interleukin-6 and -8, cell growth inhibition and morphological changes in 2-hydroxyethyl methacrylate-treated human dental pulp mesenchymal stem cells.

PubMed

Trubiani, O; Cataldi, A; De Angelis, F; D'Arcangelo, C; Caputi, S

2012-01-01

To evaluate morphological features, cell growth and interleukin-6 (IL-6) and interleukin-8 (IL-8) secretion in expanded ex vivo human dental pulp mesenchymal stem cells (DP-MSCs) after exposure to 2-hydroxyethyl methacrylate (HEMA).   Dental pulp mesenchymal stem cells were derived from the dental pulps of 10 young donors. After in vitro isolation, DP-MSCs were treated with 3 and 5 mmol L(-1) HEMA, and after 24, 48 and 72 h of incubation, their morphological features, cell growth, IL-6 and IL-8 secretion were analysed. Differences in the cell growth and in the interleukin secretion were analysed for statistical significance with two-way anova tests and the Holm-Sidak method for multiple comparisons.   Dental pulp mesenchymal stem cells revealed a decrease in cell growth with both treatments (P < 0.05), more evident at 5 mmol L(-1) . Microscopic analysis displayed extensive cytotoxic effects in treated cells, which lost their fibroblastoid features and became retracted, even roundish, with a large number of granules. An up-regulation of IL-6 and IL-8 in treated cells cytokines was evident (P < 0.05).   2-Hydroxyethyl methacrylate exhibited cytotoxicity, inhibited cell growth and induced morphological changes in cultured DP-MSCs. Moreover, in treated samples, an up-regulation of soluble mediators of inflammation such as IL-6 and IL-8 cytokines was found. The direct application of HEMA potentially induces an inflammation process that could be the starting point for toxic response and cell damage in DP-MSCs. © 2011 International Endodontic Journal.

A NEW AGAROPHYTE SPECIES, GELIDIUM EUCORNEUM SP. NOV. (GELIDIALES, RHODOPHYTA), BASED ON MOLECULAR AND MORPHOLOGICAL DATA(1).

PubMed

Kim, Kyeong Mi; Hwang, Il Ki; Park, Jeong Kwang; Boo, Sung Min

2011-08-01

Gelidium is an economically and ecologically important agar-producing genus. Although the taxonomy of Gelidium has been the focus of many published studies, there is still a need to reevaluate species-level diversity. Herein, we describe Gelidium eucorneum sp. nov. based on specimens collected off Geojedo on the southern coast of Korea. G. eucorneum is distinguished by cartilaginous thalli with brush-like haptera, rhizoidal filaments concentrated in the medulla, and globose cytocarps that are horned with multiple determinate branchlets. The species occurs in wave-exposed intertidal sites, sometimes in association with other mat-forming algae. Phylogenetic analyses (rbcL, psaA, and cox1) reveal that G. eucorneum is unique and clearly distinct from other species of the genus. The clade containing Gelidium vagum and Acanthopeltis longiramulosa was resolved as a sister group to G. eucorneum. We suggest that the diverse morphologies of G. eucorneum, G. vagum, and Acanthopeltis developed from a common ancestor in East Asian waters. This study shows that even in well-studied areas, more agarophyte species are to be added to the world inventory of red algae. © 2011 Phycological Society of America.

Coexistence of glutamatergic spine synapses and shaft synapses in substantia nigra dopamine neurons

PubMed Central

Jang, Miae; Bum Um, Ki; Jang, Jinyoung; Jin Kim, Hyun; Cho, Hana; Chung, Sungkwon; Kyu Park, Myoung

2015-01-01

Dopamine neurons of the substantia nigra have long been believed to have multiple aspiny dendrites which receive many glutamatergic synaptic inputs from several regions of the brain. But, here, using high-resolution two-photon confocal microscopy in the mouse brain slices, we found a substantial number of common dendritic spines in the nigral dopamine neurons including thin, mushroom, and stubby types of spines. However, the number of dendritic spines of the dopamine neurons was approximately five times lower than that of CA1 pyramidal neurons. Immunostaining and morphological analysis revealed that glutamatergic shaft synapses were present two times more than spine synapses. Using local two-photon glutamate uncaging techniques, we confirmed that shaft synapses and spine synapses had both AMPA and NMDA receptors, but the AMPA/NMDA current ratios differed. The evoked postsynaptic potentials of spine synapses showed lower amplitudes but longer half-widths than those of shaft synapses. Therefore, we provide the first evidence that the midbrain dopamine neurons have two morphologically and functionally distinct types of glutamatergic synapses, spine synapses and shaft synapses, on the same dendrite. This peculiar organization could be a new basis for unraveling many physiological and pathological functions of the midbrain dopamine neurons. PMID:26435058

Nanostructure and force spectroscopy analysis of human peripheral blood CD4+ T cells using atomic force microscopy.

PubMed

Hu, Mingqian; Wang, Jiongkun; Cai, Jiye; Wu, Yangzhe; Wang, Xiaoping

2008-09-12

To date, nanoscale imaging of the morphological changes and adhesion force of CD4(+) T cells during in vitro activation remains largely unreported. In this study, we used atomic force microscopy (AFM) to study the morphological changes and specific binding forces in resting and activated human peripheral blood CD4(+) T cells. The AFM images revealed that the volume of activated CD4(+) T cells increased and the ultrastructure of these cells also became complex. Using a functionalized AFM tip, the strength of the specific binding force of the CD4 antigen-antibody interaction was found to be approximately three times that of the unspecific force. The adhesion forces were not randomly distributed over the surface of a single activated CD4(+) T cell, indicated that the CD4 molecules concentrated into nanodomains. The magnitude of the adhesion force of the CD4 antigen-antibody interaction did not change markedly with the activation time. Multiple bonds involved in the CD4 antigen-antibody interaction were measured at different activation times. These results suggest that the adhesion force involved in the CD4 antigen-antibody interaction is highly selective and of high affinity.

Second harmonic generation imaging as a potential tool for staging pregnancy and predicting preterm birth

NASA Astrophysics Data System (ADS)

Akins, Meredith L.; Luby-Phelps, Katherine; Mahendroo, Mala

2010-03-01

We use second harmonic generation (SHG) microscopy to assess changes in collagen structure of murine cervix during cervical remodeling of normal pregnancy and in a preterm birth model. Visual inspection of SHG images revealed substantial changes in collagen morphology throughout normal gestation. SHG images collected in both the forward and backward directions were analyzed quantitatively for changes in overall mean intensity, forward to backward intensity ratio, collagen fiber size, and porosity. Changes in mean SHG intensity and intensity ratio take place in early pregnancy, suggesting that submicroscopic changes in collagen fibril size and arrangement occur before macroscopic changes become evident. Fiber size progressively increased from early to late pregnancy, while pores between collagen fibers became larger and farther apart. Analysis of collagen features in premature cervical remodeling show that changes in collagen structure are dissimilar from normal remodeling. The ability to quantify multiple morphological features of collagen that characterize normal cervical remodeling and distinguish abnormal remodeling in preterm birth models supports future studies aimed at development of SHG endoscopic devices for clinical assessment of collagen changes during pregnancy in women and for predicting risk of preterm labor which occurs in 12.5% of all pregnancies.

Independent Transitions between Monsoonal and Arid Biomes Revealed by Systematic Revison of a Complex of Australian Geckos (Diplodactylus; Diplodactylidae)

PubMed Central

Oliver, Paul M.; Couper, Patrick J.; Pepper, Mitzy

2014-01-01

How the widespread expansion and intensification of aridity through the Neogene has shaped the Austral biota is a major question in Antipodean biogeography. Lineages distributed across wide aridity gradients provide opportunities to examine the timing, frequency, and direction of transitions between arid and mesic regions. Here, we use molecular genetics and morphological data to investigate the systematics and biogeography of a nominal Australian gecko species (Diplodactylus conspicillatus sensu lato) with a wide distribution spanning most of the Australian Arid Zone (AAZ) and Monsoonal Tropics (AMT). Our data support a minimum of seven genetically distinct and morphologically diagnosable taxa; we thus redefine the type species, ressurrect three names from synonymy, and describe three new species. Our inferred phylogeny suggests the history and diversification of lineages in the AAZ and AMT are intimately linked, with evidence of multiple independent interchanges since the late Miocene. However, despite this shared history, related lineages in these two regions also show evidence of broadly contrasting intra-regional responses to aridification; vicarance and speciation in older and increasingly attenuated mesic regions, versus a more dynamic history including independent colonisations and recent range expansions in the younger AAZ. PMID:25493936

Fabrication, characterization and bioevaluation of silibinin loaded chitosan nanoparticles.

PubMed

Pooja, Deep; Babu Bikkina, Dileep J; Kulhari, Hitesh; Nikhila, Nalla; Chinde, Srinivas; Raghavendra, Y M; Sreedhar, B; Tiwari, Ashok K

2014-08-01

Silibinin is reported to possess multiple biological activities. However, its hydrophobic nature limits its bioavailability compromising in vivo biological activities. Nanoparticles-based delivery of such molecules has emerged as new technique to resolve these issues. Bio-degradable, compatible and adhesive nature of chitosan has recently attracted its suitability as a carrier for biologically active molecules. This study presents fabrication and characterization of chitosan-tripolyphosphate based encapsulation of silibinin. Various preparations of silibinin encapsulated chitosan-tripolyphosphate nanoparticles were studied for particle size, morphology, zeta-potential, and encapsulation efficiencies. Preparations were also evaluated for cytotoxic activities in vitro. The optimized silibinin loaded chitosan nanoparticles were of 263.7±4.1nm in particle size with zeta potential 37.4±1.57mV. Nanoparticles showed high silibinin encapsulation efficiencies (82.94±1.82%). No chemical interactions between silibinin and chitosan were observed in FTIR analysis. Powder X-ray diffraction analysis revealed transformed physical state of silibinin after encapsulation. Surface morphology and thermal behaviour were determined using TEM and DSC analysis. Encapsulated silibinin displayed increased dissolution and better cytotoxicity against human prostate cancer cells (DU145) than silibinin alone. Copyright © 2014 Elsevier B.V. All rights reserved.

Effects of heat/citric acid reprocessing on high-flux polysulfone dialyzers.

PubMed

Cornelius, Rena M; McClung, W Glenn; Richardson, Robert M A; Estridge, Charles; Plaskos, Nicholas; Yip, Christopher M; Brash, John L

2002-01-01

The surface features, morphology, and tensile properties of fibers obtained from pristine, reprocessed, and reused Fresenius Polysulfone High-Flux (Hemoflow F80A) hemodialyzers have been studied. Scanning electron microscopy of the dialyzer fibers revealed a dense skin layer on the inner surface of the membrane and a relatively thick porous layer on the outer surface. Transmission electron microscopy and atomic force microscopy showed an alteration in membrane morphology due to reprocessing and reuse, or to a deposition of blood-borne material on the membrane that is not removed with reprocessing. Fluorescent microscopy images also showed that a fluorescent material not removed by heat/citric acid reprocessing builds up with continued use of the dialyzers. The tensile properties of the dialyzer fibers were not affected by the heat/citric acid reprocessing procedure. The protein layers formed on pristine and reused hemodialyzer membranes during clinical use were also studied using sodium dodecyl sulfate polyacrylamide gel electrophoresis and immunoblotting. A considerable amount of protein was found on the blood side of single and multiple use dialyzers. Proteins adsorbed on the dialysate side of the membrane were predominantly in the molecular weight region below 30 kDa. Little protein was detected on the membranes of reprocessed hemodialyzers.

Microscopy reveals disease control through novel effects on fungal development: a case study with an early-generation benzophenone fungicide.

PubMed

Schmitt, Mark R; Carzaniga, Raffaella; Cotter, H Van T; O'Connell, Richard; Hollomon, Derek

2006-05-01

The benzophenones are a new class of agricultural fungicides that demonstrate protectant, curative and eradicative/antisporulant activity against powdery mildews. The chemistry is represented in the marketplace by the fungicide metrafenone, recently introduced by BASF and discussed in the following paper. The benzophenones show no evidence of acting by previously identified biochemical mechanisms, nor do they show cross-resistance with existing fungicides. The value of microscopy in elucidating fungicide mode of action is demonstrated through identification of the effects of an early benzophenone, eBZO, on mildew development. eBZO caused profound alterations in the morphology of powdery mildews of both monocotyledons and dicotyledons, affecting multiple stages of fungal development, including spore germination, appressorial formation, penetration, surface hyphal morphology and sporogenesis. Identification of analogous effects of eBZO on sporulation in the model organism Aspergillus nidulans (Eidam) Winter provides a unique opportunity to elucidate important morphogenetic regulatory sites in the economically important obligate pathogens, the powdery mildews. Benzophenones provide a further example of the benefits of whole-organism testing in the search for novel fungicide modes of action. Copyright 2006 Society of Chemical Industry.

Formation mechanisms for the dominant kinks with different angles in InP nanowires.

PubMed

Zhang, Minghuan; Wang, Fengyun; Wang, Chao; Wang, Yiqian; Yip, SenPo; Ho, Johnny C

2014-01-01

The morphologies and microstructures of kinked InP nanowires (NWs) prepared by solid-source chemical vapor deposition method were examined using scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). Statistical analysis and structural characterization reveal that four different kinds of kinks are dominant in the grown InP NWs with a bending angle of approximately 70°, 90°, 110°, and 170°, respectively. The formation mechanisms of these kinks are discussed. Specifically, the existence of kinks with bending angles of approximately 70° and 110° are mainly attributed to the occurrence of stacking faults and nanotwins in the NWs, which could easily form by the glide of {111} planes, while approximately 90° kinks result from the local amorphorization of InP NWs. Also, approximately 170° kinks are mainly caused by small-angle boundaries, where the insertion of extra atomic planes could make the NWs slightly bent. In addition, multiple kinks with various angles are also observed. Importantly, all these results are beneficial to understand the formation mechanisms of kinks in compound semiconductor NWs, which could guide the design of nanostructured materials, morphologies, microstructures, and/or enhanced mechanical properties.

Formation mechanisms for the dominant kinks with different angles in InP nanowires

PubMed Central

2014-01-01

The morphologies and microstructures of kinked InP nanowires (NWs) prepared by solid-source chemical vapor deposition method were examined using scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). Statistical analysis and structural characterization reveal that four different kinds of kinks are dominant in the grown InP NWs with a bending angle of approximately 70°, 90°, 110°, and 170°, respectively. The formation mechanisms of these kinks are discussed. Specifically, the existence of kinks with bending angles of approximately 70° and 110° are mainly attributed to the occurrence of stacking faults and nanotwins in the NWs, which could easily form by the glide of {111} planes, while approximately 90° kinks result from the local amorphorization of InP NWs. Also, approximately 170° kinks are mainly caused by small-angle boundaries, where the insertion of extra atomic planes could make the NWs slightly bent. In addition, multiple kinks with various angles are also observed. Importantly, all these results are beneficial to understand the formation mechanisms of kinks in compound semiconductor NWs, which could guide the design of nanostructured materials, morphologies, microstructures, and/or enhanced mechanical properties. PMID:24910572

Megafaunal split ends: microscopical characterisation of hair structure and function in extinct woolly mammoth and woolly rhino

NASA Astrophysics Data System (ADS)

Tridico, Silvana R.; Rigby, Paul; Kirkbride, K. Paul; Haile, James; Bunce, Michael

2014-01-01

The large extinct megafaunal species of the Late Pleistocene, Mammuthus primigenius (woolly mammoth) and Coelodonta antiquitatis (woolly rhino) are renowned for their pelage. Despite this, very little research has been conducted on the form and function of hair from these iconic species. Using permafrost preserved hair samples from seven extinct megafaunal remains, this study presents an in-depth microscopical characterisation of preservation, taphonomy, microbial damage, pigmentation and morphological features of more than 420 hairs. The presence of unique structural features in hairs, from two extinct megafauna species, such as multiple medullae and unparallelled stiffness suggests evolution of traits that may have been critical for their survival in the harsh arctic environment. Lastly, despite popular depictions of red-haired and/or uniformly coloured mammoths, a closer examination of pigmentation reveals that mammoth coats may have exhibited a mottled/variegated appearance and that their 'true' colours were not the vivid red/orange colour often depicted in reconstructions. Insights gained from microscopical examination of hundreds of extinct megafauna hairs demonstrate the value of extracting as much morphological data as possible from ancient hairs prior to destructive sampling for molecular analyses.

3D X-Ray Nanotomography of Cells Grown on Electrospun Scaffolds.

PubMed

Bradley, Robert S; Robinson, Ian K; Yusuf, Mohammed

2017-02-01

Here, it is demonstrated that X-ray nanotomography with Zernike phase contrast can be used for 3D imaging of cells grown on electrospun polymer scaffolds. The scaffold fibers and cells are simultaneously imaged, enabling the influence of scaffold architecture on cell location and morphology to be studied. The high resolution enables subcellular details to be revealed. The X-ray imaging conditions were optimized to reduce scan times, making it feasible to scan multiple regions of interest in relatively large samples. An image processing procedure is presented which enables scaffold characteristics and cell location to be quantified. The procedure is demonstrated by comparing the ingrowth of cells after culture for 3 and 6 days. © 2016 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Transcriptomic and epigenomic characterization of the developing bat wing

PubMed Central

Eckalbar, Walter L.; Schlebusch, Stephen A.; Mason, Mandy K.; Gill, Zoe; Parker, Ash V.; Booker, Betty M.; Nishizaki, Sierra; Muswamba-Nday, Christiane; Terhune, Elizabeth; Nevonen, Kimberly; Makki, Nadja; Friedrich, Tara; VanderMeer, Julia E.; Pollard, Katherine S.; Carbone, Lucia; Wall, Jeff D.; Illing, Nicola; Ahituv, Nadav

2016-01-01

Bats are the only mammals capable of powered flight, but little is known about the genetic determinants that shape their wings. Here, we generated a genome for Miniopterus natalensis and performed RNA-seq and ChIP-seq (H3K27ac, H3K27me3) on its developing forelimb and hindlimb autopods at sequential embryonic stages to decipher the molecular events that underlie bat wing development. Over 7,000 genes and several lncRNAs, including Tbx5-as1 and Hottip, were differentially expressed between forelimb, hindlimb and different stages. ChIP-seq identified thousands of regions that are differentially modified in forelimb versus hindlimb. Comparative genomics found 2,796 bat-accelerated regions within H3K27ac peaks, several of which cluster near limb-associated genes. Pathway analyses revealed multiple ribosomal proteins and known limb patterning signaling pathways as differentially regulated, and implicated increased forelimb mesenchymal condensations with differential growth. Combined, our work outlines multiple genetic components that contribute to bat wing formation, providing a genomic blueprint for this morphological innovation. PMID:27019111

Report of dysgerminoma in the ovaries of a snapping turtle (Chelydra serpentina) with discussion of ovarian neoplasms reported in reptilians and women.

PubMed

Machotka, S V; Wisser, J; Ippen, R; Nawab, E

1992-01-01

A malnourished, captive, young adult (weight-11 kg, carapace length-25 cm), female snapping turtle (Chelydra serpentina) was presented for examination and treatment of malnutrition and multiple carapace necroses. Because treatment was unsuccessful, the animal was euthanatized and necropsied. The main necropsy observations showed the presence of a 9 cm greyish-white/yellow, soft, fleshy to fatlike mass involving the right ovary near the oviduct opening and multiple similar, pea-to-walnut sized masses involving both ovaries. Microscopic examination of formalin fixed, hematoxylin and eosin and silver stained tissue sections revealed the masses to be composed of primordial germ cells arranged in a pattern morphologically compatible with dysgerminoma as described in women and other mammals. Very rarely have ovarian neoplasms been reported in turtles or other reptiles. This is the first neoplasm described in the snapping turtle ovary and the first dysgerminoma reported in reptilians. A tabulation of previously documented ovarian neoplasia in reptiles and a comparison of this cancer to those occurring in women will be discussed.

Phylogenetic studies favour the unification of Pennisetum, Cenchrus and Odontelytrum (Poaceae): a combined nuclear, plastid and morphological analysis, and nomenclatural combinations in Cenchrus.

PubMed

Chemisquy, M Amelia; Giussani, Liliana M; Scataglini, María A; Kellogg, Elizabeth A; Morrone, Osvaldo

2010-07-01

Twenty-five genera having sterile inflorescence branches were recognized as the bristle clade within the x = 9 Paniceae (Panicoideae). Within the bristle clade, taxonomic circumscription of Cenchrus (20-25 species), Pennisetum (80-140) and the monotypic Odontelytrum is still unclear. Several criteria have been applied to characterize Cenchrus and Pennisetum, but none of these has proved satisfactory as the diagnostic characters, such as fusion of bristles in the inflorescences, show continuous variation. A phylogenetic analysis based on morphological, plastid (trnL-F, ndhF) and nuclear (knotted) data is presented for a representative species sampling of the genera. All analyses were conducted under parsimony, using heuristic searches with TBR branch swapping. Branch support was assessed with parsimony jackknifing. Based on plastid and morphological data, Pennisetum, Cenchrus and Odontelytrum were supported as a monophyletic group: the PCO clade. Only one section of Pennisetum (Brevivalvula) was supported as monophyletic. The position of P. lanatum differed among data partitions, although the combined plastid and morphology and nuclear analyses showed this species to be a member of the PCO clade. The basic chromosome number x = 9 was found to be plesiomorphic, and x = 5, 7, 8, 10 and 17 were derived states. The nuclear phylogenetic analysis revealed a reticulate pattern of relationships among Pennisetum and Cenchrus, suggesting that there are at least three different genomes. Because apomixis can be transferred among species through hybridization, its history most likely reflects crossing relationships, rather than multiple independent appearances. Due to the consistency between the present results and different phylogenetic hypotheses (including morphological, developmental and multilocus approaches), and the high support found for the PCO clade, also including the type species of the three genera, we propose unification of Pennisetum, Cenchrus and Odontelytrum. Species of Pennisetum and Odontelytrum are here transferred into Cenchrus, which has priority. Sixty-six new combinations are made here.

Morphological development of the Florida Escarpment: Observations on the generation of time transgressive unconformities in carbonate terrains

USGS Publications Warehouse

Paull, C.K.; Twichell, D.C.; Spiess, Fred N.; Curray, Joseph R.

1991-01-01

An unconformity of 100 m.yr magnitude continues to form on the western edge of the Florida-Bahama Platform, near 26??N, where distal Mississippi Fan sediments are progressively burying the Florida Escarpment. Multiple perspectives of the developing unconformity's morphology are revealed using available technologies including GLORIA images of the entire platform's edge, Seabeam bathymetric contours, and Deep-Tow's high resolution side-scan data calibrated with bottom photographs. The structure and stratigraphy of the buried escarpment and the associated unconformity are resolved by airgun, sparker, and Deep-Tow's 4 kHz seismic reflection data; we summarize the morphological data on the exposed part of the unconformity and the sedimentary deposits accumulating in the basin above the unconformity. The exposed cliff face is composed of a staircase of bedding-plane terraces which are developed along joint planes. The terraces extend 100-1000 m along the escarpment's face, and the intervening vertical walls are up to 100 m high. The jointed morphology of this Mesozoic limestone cliff apparently reflects erosional exposure of its interior anatomy rather than its accretionary shape. The change in slope between the platform face and the abyssal plain is very abrupt. In places along the contact between the escarpment and fan sediments, reduced chemical-charged brine seeps occur, which locally cause carbonate dissolution and precipitation, sulfide mineralization, and the deposition of a fossiliferous and organic carbon-rich lens associated with chemosynthetic communities. These seep deposits and escarpment-derived megabreccias intercalate with basinal sediments that overlie the unconformity. Because surface seismic reflection data do not produce images of the escarpment's face that closely reflect the exposed escarpment's morphology, they must also be of limited value in characterizing the surface of similar steeply dipping buried escarpments. Thus, the downslope extent of the heavily eroded platform edge is unclear. 

Phylogenetic studies favour the unification of Pennisetum, Cenchrus and Odontelytrum (Poaceae): a combined nuclear, plastid and morphological analysis, and nomenclatural combinations in Cenchrus

PubMed Central

Chemisquy, M. Amelia; Giussani, Liliana M.; Scataglini, María A.; Kellogg, Elizabeth A.; Morrone, Osvaldo

2010-01-01

Backgrounds and Aims Twenty-five genera having sterile inflorescence branches were recognized as the bristle clade within the x = 9 Paniceae (Panicoideae). Within the bristle clade, taxonomic circumscription of Cenchrus (20–25 species), Pennisetum (80–140) and the monotypic Odontelytrum is still unclear. Several criteria have been applied to characterize Cenchrus and Pennisetum, but none of these has proved satisfactory as the diagnostic characters, such as fusion of bristles in the inflorescences, show continuous variation. Methods A phylogenetic analysis based on morphological, plastid (trnL-F, ndhF) and nuclear (knotted) data is presented for a representative species sampling of the genera. All analyses were conducted under parsimony, using heuristic searches with TBR branch swapping. Branch support was assessed with parsimony jackknifing. Key Results Based on plastid and morphological data, Pennisetum, Cenchrus and Odontelytrum were supported as a monophyletic group: the PCO clade. Only one section of Pennisetum (Brevivalvula) was supported as monophyletic. The position of P. lanatum differed among data partitions, although the combined plastid and morphology and nuclear analyses showed this species to be a member of the PCO clade. The basic chromosome number x = 9 was found to be plesiomorphic, and x = 5, 7, 8, 10 and 17 were derived states. The nuclear phylogenetic analysis revealed a reticulate pattern of relationships among Pennisetum and Cenchrus, suggesting that there are at least three different genomes. Because apomixis can be transferred among species through hybridization, its history most likely reflects crossing relationships, rather than multiple independent appearances. Conclusions Due to the consistency between the present results and different phylogenetic hypotheses (including morphological, developmental and multilocus approaches), and the high support found for the PCO clade, also including the type species of the three genera, we propose unification of Pennisetum, Cenchrus and Odontelytrum. Species of Pennisetum and Odontelytrum are here transferred into Cenchrus, which has priority. Sixty-six new combinations are made here. PMID:20570830

Phenotypic variation as an indicator of pesticide stress in gudgeon: Accounting for confounding factors in the wild.

PubMed

Shinn, Cândida; Blanchet, Simon; Loot, Géraldine; Lek, Sovan; Grenouillet, Gaël

2015-12-15

The response of organisms to environmental stress is currently used in the assessment of ecosystem health. Morphological changes integrate the multiple effects of one or several stress factors upon the development of the exposed organisms. In a natural environment, many factors determine the patterns of morphological differentiation between individuals. However, few studies have sought to distinguish and measure the independent effect of these factors (genetic diversity and structure, spatial structuring of populations, physical-chemical conditions, etc.). Here we investigated the relationship between pesticide levels measured at 11 sites sampled in rivers of the Garonne river basin (SW France) and morphological changes of a freshwater fish species, the gudgeon (Gobio gobio). Each individual sampled was genotyped using 8 microsatellite markers and their phenotype characterized via 17 morphological traits. Our analysis detected a link between population genetic structure (revealed by a Bayesian method) and morphometry (linear discriminant analysis) of the studied populations. We then developed an original method based on general linear models using distance matrices, an extension of the partial Mantel test beyond 3 matrices. This method was used to test the relationship between contamination (toxicity index) and morphometry (PST of morphometric traits), taking into account (1) genetic differentiation between populations (FST), (2) geographical distances between sites, (3) site catchment area, and (4) various physical-chemical parameters for each sampling site. Upon removal of confounding effects, 3 of the 17 morphological traits studied were significantly correlated with pesticide toxicity, suggesting a response of these traits to the anthropogenic stress. These results underline the importance of taking into account the different sources of phenotypic variability between organisms when identifying the stress factors involved. The separation and quantification of the independent effect of such factors provides an interesting outlook regarding the use of these evaluation metrics as indicators of ecosystem health. Copyright © 2015 Elsevier B.V. All rights reserved.

Hebrew Brain vs. English Brain: Language Modulates the Way It Is Processed

ERIC Educational Resources Information Center

Bick, Atira S.; Goelman, Gadi; Frost, Ram

2011-01-01

Is language processing universal? How do the specific properties of each language influence the way it is processed? In this study, we compare the neural correlates of morphological processing in Hebrew--a Semitic language with a rich and systematic morphology, to those revealed in English--an Indo-European language with a linear morphology. Using…

The Development of the Hebrew Mental Lexicon: When Morphological Representations become Devoid of Their Meaning

ERIC Educational Resources Information Center

Schiff, Rachel; Raveh, Michal; Fighel, Avital

2012-01-01

This study investigated the effect of semantic inconsistency of roots on morphological processing to explore the development of morphological representations within the mental lexicon. We examined masked priming of Hebrew words of changing semantic transparency at two reading levels. The results revealed a disparity in the performance of fourth…

Reach-scale channel sensitivity to multiple human activities and natural events: Lower Santa Clara River, California, USA

NASA Astrophysics Data System (ADS)

Downs, Peter W.; Dusterhoff, Scott R.; Sears, William A.

2013-05-01

Understanding the cumulative impact of natural and human influences on the sensitivity of channel morphodynamics, a relative measure between the drivers for change and the magnitude of channel response, requires an approach that accommodates spatial and temporal variability in the suite of primary stressors. Multiple historical data sources were assembled to provide a reach-scale analysis of the lower Santa Clara River (LSCR) in Ventura County, California, USA. Sediment supply is naturally high due to tectonic activity, earthquake-generated landslides, wildfires, and high magnitude flow events during El Niño years. Somewhat typically for the region, the catchment has been subject to four reasonably distinct land use and resource management combinations since European-American settlement. When combined with analysis of channel morphological response (quantifiable since ca. 1930), reach-scale and temporal differences in channel sensitivity become apparent. Downstream reaches have incised on average 2.4 m and become narrower by almost 50% with changes focused in a period of highly sensitive response after about 1950 followed by forced insensitivity caused by structural flood embankments and a significant grade control structure. In contrast, the middle reaches have been responsive but are morphologically resilient, and the upstream reaches show a mildly sensitive aggradational trend. Superimposing the natural and human drivers for change reveals that large scale stressors (related to ranching and irrigation) have been replaced over time by a suite of stressors operating at multiple spatial scales. Lower reaches have been sensitive primarily to 'local' scale impacts (urban growth, flood control, and aggregate mining) whereas, upstream, catchment-scale influences still prevail (including flow regulation and climate-driven sediment supply factors). These factors illustrate the complexity inherent to cumulative impact assessment in fluvial systems, provide evidence for a distinct Anthropocene fluvial response, and underpin the enormity of the challenge faced in trying to sustainably manage and restore rivers.

ONC201 kills breast cancer cells in vitro by targeting mitochondria.

PubMed

Greer, Yoshimi Endo; Porat-Shliom, Natalie; Nagashima, Kunio; Stuelten, Christina; Crooks, Dan; Koparde, Vishal N; Gilbert, Samuel F; Islam, Celia; Ubaldini, Ashley; Ji, Yun; Gattinoni, Luca; Soheilian, Ferri; Wang, Xiantao; Hafner, Markus; Shetty, Jyoti; Tran, Bao; Jailwala, Parthav; Cam, Maggie; Lang, Martin; Voeller, Donna; Reinhold, William C; Rajapakse, Vinodh; Pommier, Yves; Weigert, Roberto; Linehan, W Marston; Lipkowitz, Stanley

2018-04-06

We report a novel mechanism of action of ONC201 as a mitochondria-targeting drug in cancer cells. ONC201 was originally identified as a small molecule that induces transcription of TNF-related apoptosis-inducing ligand (TRAIL) and subsequently kills cancer cells by activating TRAIL death receptors. In this study, we examined ONC201 toxicity on multiple human breast and endometrial cancer cell lines. ONC201 attenuated cell viability in all cancer cell lines tested. Unexpectedly, ONC201 toxicity was not dependent on either TRAIL receptors nor caspases. Time-lapse live cell imaging revealed that ONC201 induces cell membrane ballooning followed by rupture, distinct from the morphology of cells undergoing apoptosis. Further investigation found that ONC201 induces phosphorylation of AMP-dependent kinase and ATP loss. Cytotoxicity and ATP depletion were significantly enhanced in the absence of glucose, suggesting that ONC201 targets mitochondrial respiration. Further analysis indicated that ONC201 indirectly inhibits mitochondrial respiration. Confocal and electron microscopic analysis demonstrated that ONC201 triggers mitochondrial structural damage and functional impairment. Moreover, ONC201 decreased mitochondrial DNA (mtDNA). RNAseq analysis revealed that ONC201 suppresses expression of multiple mtDNA-encoded genes and nuclear-encoded mitochondrial genes involved in oxidative phosphorylation and other mitochondrial functions. Importantly, fumarate hydratase deficient cancer cells and multiple cancer cell lines with reduced amounts of mtDNA were resistant to ONC201. These results indicate that cells not dependent on mitochondrial respiration are ONC201-resistant. Our data demonstrate that ONC201 kills cancer cells by disrupting mitochondrial function and further suggests that cancer cells that are dependent on glycolysis will be resistant to ONC201.

ONC201 kills breast cancer cells in vitro by targeting mitochondria

PubMed Central

Greer, Yoshimi Endo; Porat-Shliom, Natalie; Nagashima, Kunio; Stuelten, Christina; Crooks, Dan; Koparde, Vishal N.; Gilbert, Samuel F.; Islam, Celia; Ubaldini, Ashley; Ji, Yun; Gattinoni, Luca; Soheilian, Ferri; Wang, Xiantao; Hafner, Markus; Shetty, Jyoti; Tran, Bao; Jailwala, Parthav; Cam, Maggie; Lang, Martin; Voeller, Donna; Reinhold, William C.; Rajapakse, Vinodh; Pommier, Yves; Weigert, Roberto; Linehan, W. Marston; Lipkowitz, Stanley

2018-01-01

We report a novel mechanism of action of ONC201 as a mitochondria-targeting drug in cancer cells. ONC201 was originally identified as a small molecule that induces transcription of TNF-related apoptosis-inducing ligand (TRAIL) and subsequently kills cancer cells by activating TRAIL death receptors. In this study, we examined ONC201 toxicity on multiple human breast and endometrial cancer cell lines. ONC201 attenuated cell viability in all cancer cell lines tested. Unexpectedly, ONC201 toxicity was not dependent on either TRAIL receptors nor caspases. Time-lapse live cell imaging revealed that ONC201 induces cell membrane ballooning followed by rupture, distinct from the morphology of cells undergoing apoptosis. Further investigation found that ONC201 induces phosphorylation of AMP-dependent kinase and ATP loss. Cytotoxicity and ATP depletion were significantly enhanced in the absence of glucose, suggesting that ONC201 targets mitochondrial respiration. Further analysis indicated that ONC201 indirectly inhibits mitochondrial respiration. Confocal and electron microscopic analysis demonstrated that ONC201 triggers mitochondrial structural damage and functional impairment. Moreover, ONC201 decreased mitochondrial DNA (mtDNA). RNAseq analysis revealed that ONC201 suppresses expression of multiple mtDNA-encoded genes and nuclear-encoded mitochondrial genes involved in oxidative phosphorylation and other mitochondrial functions. Importantly, fumarate hydratase deficient cancer cells and multiple cancer cell lines with reduced amounts of mtDNA were resistant to ONC201. These results indicate that cells not dependent on mitochondrial respiration are ONC201-resistant. Our data demonstrate that ONC201 kills cancer cells by disrupting mitochondrial function and further suggests that cancer cells that are dependent on glycolysis will be resistant to ONC201. PMID:29719618

PA-GFP: a window into the subcellular adventures of the individual mitochondrion.

PubMed

Haigh, Sarah E; Twig, Gilad; Molina, Anthony A J; Wikstrom, Jakob D; Deutsch, Motti; Shirihai, Orian S

2007-01-01

Mitochondrial connectivity is characterized by matrix lumen continuity and by dynamic rewiring through fusion and fission events. While these mechanisms homogenize the mitochondrial population, a number of studies looking at mitochondrial membrane potential have demonstrated that mitochondria exist as a heterogeneous population within individual cells. To address the relationship between mitochondrial dynamics and heterogeneity, we tagged and tracked individual mitochondria over time while monitoring their mitochondrial membrane potential (deltapsi(m)). By utilizing photoactivatible-GFP (PA-GFP), targeted to the mitochondrial matrix, we determined the boundaries of the individual mitochondrion. A single mitochondrion is defined by the continuity of its matrix lumen. The boundaries set by luminal continuity matched those set by electrical coupling, indicating that the individual mitochondrion is equipotential throughout the entire organelle. Similar results were obtained with PA-GFP targeted to the inner membrane indicating that matrix continuity parallels inner membrane continuity. Sequential photoconversion of matrix PA-GFP in multiple locations within the mitochondrial web reveals that each ramified mitochondrial structure is composed of juxtaposed but discontinuous units. Moreover, as many as half of the events in which mitochondria come into contact, do not result in fusion. While all fission events generated two electrically uncoupled discontinuous matrices, the two daughter mitochondria frequently remained juxtaposed, keeping the tubular appearance unchanged. These morphologically invisible fission events illustrate the difference between mitochondrial fission and fragmentation; the latter representing the movement and separation of disconnected units. Simultaneous monitoring of deltapsi(m) of up to four individual mitochondria within the same cell revealed that subcellular heterogeneity in deltapsi(m) does not represent multiple unstable mitochondria that appear 'heterogeneous' at any given point, but rather multiple stable, but heterogeneous units.

Multiple Polyploidization Events across Asteraceae with Two Nested Events in the Early History Revealed by Nuclear Phylogenomics.

PubMed

Huang, Chien-Hsun; Zhang, Caifei; Liu, Mian; Hu, Yi; Gao, Tiangang; Qi, Ji; Ma, Hong

2016-11-01

Biodiversity results from multiple evolutionary mechanisms, including genetic variation and natural selection. Whole-genome duplications (WGDs), or polyploidizations, provide opportunities for large-scale genetic modifications. Many evolutionarily successful lineages, including angiosperms and vertebrates, are ancient polyploids, suggesting that WGDs are a driving force in evolution. However, this hypothesis is challenged by the observed lower speciation and higher extinction rates of recently formed polyploids than diploids. Asteraceae includes about 10% of angiosperm species, is thus undoubtedly one of the most successful lineages and paleopolyploidization was suggested early in this family using a small number of datasets. Here, we used genes from 64 new transcriptome datasets and others to reconstruct a robust Asteraceae phylogeny, covering 73 species from 18 tribes in six subfamilies. We estimated their divergence times and further identified multiple potential ancient WGDs within several tribes and shared by the Heliantheae alliance, core Asteraceae (Asteroideae-Mutisioideae), and also with the sister family Calyceraceae. For two of the WGD events, there were subsequent great increases in biodiversity; the older one proceeded the divergence of at least 10 subfamilies within 10 My, with great variation in morphology and physiology, whereas the other was followed by extremely high species richness in the Heliantheae alliance clade. Our results provide different evidence for several WGDs in Asteraceae and reveal distinct association among WGD events, dramatic changes in environment and species radiations, providing a possible scenario for polyploids to overcome the disadvantages of WGDs and to evolve into lineages with high biodiversity. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Topsy-turvy locomotion: biomechanical specializations of the elbow in suspended quadrupeds reflect inverted gravitational constraints

PubMed Central

Fujiwara, Shin-ichi; Endo, Hideki; Hutchinson, John R

2011-01-01

Some tetrapods hang upside down from tree branches when moving horizontally. The ability to walk in quadrupedal suspension has been acquired independently in at least 14 mammalian lineages. During the stance (supportive) phase of quadrupedal suspension, the elbow joint flexor muscles (not the extensors as in upright vertebrates moving overground) are expected to contract to maintain the flexed limb posture. Therefore muscular control in inverted, suspended quadrupeds may require changes of muscle control, and even morphologies, to conditions opposite to those in upright animals. However, the relationships between musculoskeletal morphologies and elbow joint postures during the stance phase in suspended quadrupeds have not been investigated. Our analysis comparing postures and skeletal morphologies in Choloepus (Pilosa), Pteropus (Chiroptera), Nycticebus (Primates) and Cynocephalus (Dermoptera) revealed that the elbow joints of these animals were kept at flexed angles of 70–100 ° during the stance phase of quadrupedal suspension. At these joint angles the moment arms of the elbow joint flexors were roughly maximized, optimizing that component of antigravity support. Our additional measurements from various mammalian species show that suspended quadrupeds have relatively small extensor/flexor ratios in both muscle masses and maximum moment arms. Thus, in contrast to the pattern in normal terrestrial quadrupeds, suspended quadrupeds emphasize flexor over extensor muscles for body support. This condition has evolved independently multiple times, attendant with a loss or reduction of the ability to move in normal upright postures. PMID:21477151

Multiple thermal transitions and anisotropic thermal expansions of vertically aligned carbon nanotubes

NASA Astrophysics Data System (ADS)

Ya'akobovitz, Assaf

2016-10-01

Vertically aligned carbon nanotubes (VA-CNTs) hold the potential to play an instrumental role in a wide variety of applications in micro- and nano-devices and composites. However, their successful large-scale implementation in engineering systems requires a thorough understanding of their material properties, including their thermal behavior, which was the focus of the current study. Thus, the thermal expansion of as-grown VA-CNT microstructures was investigated while increasing the temperature from room temperature to 800 °C and then cooling it down. First thermal transition was observed at 191 ± 68 °C during heating, and an additional thermal transition was observed at 523 ± 138 °C during heating and at similar temperatures during cooling. Each thermal transition was characterized by a significant change in the coefficient of thermal expansion (CTE), which can be related to a morphological change in the VA-CNT microstructures. Measurements of the CTEs in the lateral directions revealed differences in the lateral thermal behaviors of the top, middle, and bottom portions of the VA-CNT microstructures, again indicating that their morphology dominates their thermal characteristics. A hysteretic behavior was observed, as the measured values of CTEs were altered due to the applied thermal loads and the height of the microstructures was slightly higher compared to its initial value. These findings provide an insight into the anisotropic thermal behavior of VA-CNT microstructures and shed light on the relationship between their morphology and thermal behavior.

Abnormal hippocampal shape in offenders with psychopathy.

PubMed

Boccardi, Marina; Ganzola, Rossana; Rossi, Roberta; Sabattoli, Francesca; Laakso, Mikko P; Repo-Tiihonen, Eila; Vaurio, Olli; Könönen, Mervi; Aronen, Hannu J; Thompson, Paul M; Frisoni, Giovanni B; Tiihonen, Jari

2010-03-01

Posterior hippocampal volumes correlate negatively with the severity of psychopathy, but local morphological features are unknown. The aim of this study was to investigate hippocampal morphology in habitually violent offenders having psychopathy. Manual tracings of hippocampi from magnetic resonance images of 26 offenders (age: 32.5 +/- 8.4), with different degrees of psychopathy (12 high, 14 medium psychopathy based on the Psychopathy Checklist Revised), and 25 healthy controls (age: 34.6 +/- 10.8) were used for statistical modelling of local changes with a surface-based radial distance mapping method. Both offenders and controls had similar hippocampal volume and asymmetry ratios. Local analysis showed that the high psychopathy group had a significant depression along the longitudinal hippocampal axis, on both the dorsal and ventral aspects, when compared with the healthy controls and the medium psychopathy group. The opposite comparison revealed abnormal enlargement of the lateral borders in both the right and left hippocampi of both high and medium psychopathy groups versus controls, throughout CA1, CA2-3 and the subicular regions. These enlargement and reduction effects survived statistical correction for multiple comparisons in the main contrast (26 offenders vs. 25 controls) and in most subgroup comparisons. A statistical check excluded a possible confounding effect from amphetamine and polysubstance abuse. These results indicate that habitually violent offenders exhibit a specific abnormal hippocampal morphology, in the absence of total gray matter volume changes, that may relate to different autonomic modulation and abnormal fear-conditioning. 2009 Wiley-Liss, Inc.

Comparative Tectonics of Europa and Ganymede

NASA Astrophysics Data System (ADS)

Pappalardo, R. T.; Collins, G. C.; Prockter, L. M.; Head, J. W.

2000-10-01

Europa and Ganymede are sibling satellites with tectonic similarities and differences. Ganymede's ancient dark terrain is crossed by furrows, probably related to ancient large impacts, and has been normal faulted to various degrees. Bright grooved is pervasively deformed at multiple scales and is locally highly strained, consistent with normal faulting of an ice-rich lithosphere above a ductile asthenosphere, along with minor horizontal shear. Little evidence has been identified for compressional structures. The relative roles of tectonism and icy cryovolcanism in creating bright grooved terrain is an outstanding issue. Some ridge and trough structures within Europa's bands show tectonic similarities to Ganymede's grooved terrain, specifically sawtooth structures resembling normal fault blocks. Small-scale troughs are consistent with widened tension fractures. Shearing has produced transtensional and transpressional structures in Europan bands. Large-scale folds are recognized on Europa, with synclinal small-scale ridges and scarps probably representing folds and/or thrust blocks. Europa's ubiquitous double ridges may have originated as warm ice upwelled along tidally heated fracture zones. The morphological variety of ridges and troughs on Europa imply that care must be taken in inferring their origin. The relative youth of Europa's surface means that the satellite has preserved near-pristine morphologies of many structures, though sputter erosion could have altered the morphology of older topography. Moderate-resolution imaging has revealed lesser apparent diversity in Ganymede's ridge and trough types. Galileo's 28th orbit has brought new 20 m/pixel imaging of Ganymede, allowing direct comparison to Europa's small-scale structures.

Substrate Curvature Restricts Spreading and Induces Differentiation of Human Mesenchymal Stem Cells.

PubMed

Lee, Sang Joo; Yang, Shengyuan

2017-09-01

While cells attach, spread, migrate, proliferate, and differentiate in three-dimensional (3D) micromechanical environments, the mechanical factors of these environments influence the shapes, sizes, and adhesion forces of the cells. Here, the authors culture human mesenchymal stem cells (hMSCs) on a unique class of curvature-defined substrates, micro glass ball embedded polyacrylamide gels, prepared with an improved protocol, and investigate the spreading responses of the hMSCs on the glass balls to study the effects of substrate curvature on the spreading of hMSCs. The authors find that, among the used diameters of glass balls, the minimum diameter of a glass ball on which an hMSC can attach and spread is 500 μm. In contrast to the well-spread morphologies with randomly-multiple lamellipodia for the hMSCs growing on the flat glass plates, the morphologies of the hMSCs growing on the glass balls are almost uniformly spindle-shaped with two lamellipodia. The sensitivities of the attachment and spreading morphology of an hMSC to substrate curvature are very different from those of a fibroblast. The RT-PCR analysis reveals that the substrate curvature alone can induce adipogenesis of the hMSCs. These findings imply that substrate curvature has profound effects on stem cell behaviors, and detailed and in-depth studies on these effects and their underlying biophysical mechanisms are necessary. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Colloidal synthesis of Cu-ZnO and Cu@CuNi-ZnO hybrid nanocrystals with controlled morphologies and multifunctional properties

NASA Astrophysics Data System (ADS)

Zeng, Deqian; Gong, Pingyun; Chen, Yuanzhi; Zhang, Qinfu; Xie, Qingshui; Peng, Dong-Liang

2016-06-01

Metal-semiconductor hybrid nanocrystals have received extensive attention owing to their multiple functionalities which can find wide technological applications. The utilization of low-cost non-noble metals to construct novel metal-semiconductor hybrid nanocrystals is important and meaningful for their large-scale applications. In this study, a facile solution approach is developed for the synthesis of Cu-ZnO hybrid nanocrystals with well-controlled morphologies, including nanomultipods, core-shell nanoparticles, nanopyramids and core-shell nanowires. In the synthetic strategy, Cu nanocrystals formed in situ serve as seeds for the heterogeneous nucleation and growth of ZnO, and it eventually forms various Cu-ZnO hetero-nanostructures under different reaction conditions. These hybrid nanocrystals possess well-defined and stable heterostructure junctions. The ultraviolet-visible-near infrared spectra reveal morphology-dependent surface plasmon resonance absorption of Cu and the band gap absorption of ZnO. Furthermore, we construct a novel Cu@CuNi-ZnO ternary hetero-nanostructure by incorporating the magnetic metal Ni into the pre-synthesized colloidal Cu nanocrystals. Such hybrid nanocrystals possess a magnetic Cu-Ni intermediate layer between the ZnO shell and the Cu core, and exhibit ferromagnetic/superparamagnetic properties which expand their functionalities. Finally, enhanced photocatalytic activities are observed in the as-prepared non-noble metal-ZnO hybrid nanocrystals. This study not only provides an economical way to prepare high-quality morphology-controlled Cu-ZnO hybrid nanocrystals for potential applications in the fields of photocatalysis and photovoltaic devices, but also opens up new opportunities in designing ternary non-noble metal-semiconductor hybrid nanocrystals with multifunctionalities.Metal-semiconductor hybrid nanocrystals have received extensive attention owing to their multiple functionalities which can find wide technological applications. The utilization of low-cost non-noble metals to construct novel metal-semiconductor hybrid nanocrystals is important and meaningful for their large-scale applications. In this study, a facile solution approach is developed for the synthesis of Cu-ZnO hybrid nanocrystals with well-controlled morphologies, including nanomultipods, core-shell nanoparticles, nanopyramids and core-shell nanowires. In the synthetic strategy, Cu nanocrystals formed in situ serve as seeds for the heterogeneous nucleation and growth of ZnO, and it eventually forms various Cu-ZnO hetero-nanostructures under different reaction conditions. These hybrid nanocrystals possess well-defined and stable heterostructure junctions. The ultraviolet-visible-near infrared spectra reveal morphology-dependent surface plasmon resonance absorption of Cu and the band gap absorption of ZnO. Furthermore, we construct a novel Cu@CuNi-ZnO ternary hetero-nanostructure by incorporating the magnetic metal Ni into the pre-synthesized colloidal Cu nanocrystals. Such hybrid nanocrystals possess a magnetic Cu-Ni intermediate layer between the ZnO shell and the Cu core, and exhibit ferromagnetic/superparamagnetic properties which expand their functionalities. Finally, enhanced photocatalytic activities are observed in the as-prepared non-noble metal-ZnO hybrid nanocrystals. This study not only provides an economical way to prepare high-quality morphology-controlled Cu-ZnO hybrid nanocrystals for potential applications in the fields of photocatalysis and photovoltaic devices, but also opens up new opportunities in designing ternary non-noble metal-semiconductor hybrid nanocrystals with multifunctionalities. Electronic supplementary information (ESI) available: Synthesis and TEM images of pure ZnO nanocrystals. Photocatalytic testing procedures and degradation curves. SEM and TEM images, SAED pattern and EDS spectra and maps of parts of Cu-ZnO hybrid samples. A schematic image of coincident lattice matching between Cu and ZnO. STEM-EDS elemental maps and XRD pattern of the Cu@CuNi-ZnO sample. Comparative synthetic parameters. See DOI: 10.1039/c6nr02055k

Debris avalanches and slumps on the margins of volcanic domes on Venus: Characteristics of deposits

NASA Technical Reports Server (NTRS)

Bulmer, M. H.; Guest, J. E.; Beretan, K.; Michaels, Gregory A.; Saunders, R. Stephen

1992-01-01

Modified volcanic domes, referred to as collapsed margin domes, have diameters greater than those of terrestrial domes and were therefore thought to have no suitable terrestrial analogue. Comparison of the collapsed debris using the Magellan SAR images with volcanic debris avalanches on Earth has revealed morphological similarities. Some volcanic features identified on the seafloor from sonar images have diameters similar to those on Venus and also display scalloped margins, indicating modification by collapse. Examination of the SAR images of collapsed dome features reveals a number of distinct morphologies to the collapsed masses. Ten examples of collapsed margin domes displaying a range of differing morphologies and collapsed masses have been selected and examined.

Morphology transition of the primary silicon particles in a hypereutectic A390 alloy in high pressure die casting.

PubMed

Wang, J; Guo, Z; Song, J L; Hu, W X; Li, J C; Xiong, S M

2017-11-03

The microstructure of a high-pressure die-cast hypereutectic A390 alloy, including PSPs, pores, α-Al grains and Cu-rich phases, was characterized using synchrotron X-ray tomography, together with SEM, TEM and EBSD. The Cu-rich phases exhibited a net morphology and distributed at the boundaries of the α-Al grains, which in turn surrounded the PSPs. Statistical analysis of the reconstructed 1000 PSPs showed that both equivalent diameter and shape factor of the PSPs exhibited a unimodal distribution with peaks corresponding to 25 μm and 0.78, respectively.) PSPs morphology with multiple twinning were observed and morphological or growth transition of the PSPs from regular octahedral shape (with a shape factor of 0.85 was mainly caused by the constraint of the Cu-rich phases. In particular, the presence of the Cu-rich phases restricted the growth of the α-Al grains, inducing stress on the internal silicon particles, which caused multiple twinning occurrence with higher growth potential and consequently led to growth transitions of the PSPs.

Ordered three- and five-ply nanocomposites from ABC block terpolymer microphase separation with niobia and aluminosilicate sols

PubMed Central

Stefik, Morgan; Mahajan, Surbhi; Sai, Hiroaki; Epps, Thomas H.; Bates, Frank S.; Gruner, Sol M; DiSalvo, Francis J.; Wiesner, Ulrich

2009-01-01

We report the first use of a non-frustrated block terpolymer for the synthesis of highly ordered oxide nanocomposites containing multiple plies. The morphological behavior of 15 ISO-oxide nanocomposites was investigated spanning a large range of compositions along the ƒI=ƒS isopleth using aluminosilicate and niobia sols. Morphologies were determined by TEM and SAXS measurements. Four morphologies were identified, including core-shell hexagonal, core-shell double gyroid, three-domain lamellae, and core-shell inverse-hexagonal, in order of increasing O+oxide vol fraction. All of the resulting nanocomposites had three- or five-ply morphologies containing domains that were continuous in one, two, or three dimensions. The five-ply core-shell double gyroid phase was only found to be stable when the O+oxide domain was a minority. Removal of the polymer enabled simple and direct synthesis of mesoporous oxide materials while retaining the ordered network structure. We believe that advances in the synthesis of multi-ply nanocomposites will lead to advanced materials and devices containing multiple plies of functional materials. PMID:20209023

Ordered three- and five-ply nanocomposites from ABC block terpolymer microphase separation with niobia and aluminosilicate sols.

PubMed

Stefik, Morgan; Mahajan, Surbhi; Sai, Hiroaki; Epps, Thomas H; Bates, Frank S; Gruner, Sol M; Disalvo, Francis J; Wiesner, Ulrich

2009-11-24

We report the first use of a non-frustrated block terpolymer for the synthesis of highly ordered oxide nanocomposites containing multiple plies. The morphological behavior of 15 ISO-oxide nanocomposites was investigated spanning a large range of compositions along the ƒ(I)=ƒ(S) isopleth using aluminosilicate and niobia sols. Morphologies were determined by TEM and SAXS measurements. Four morphologies were identified, including core-shell hexagonal, core-shell double gyroid, three-domain lamellae, and core-shell inverse-hexagonal, in order of increasing O+oxide vol fraction. All of the resulting nanocomposites had three- or five-ply morphologies containing domains that were continuous in one, two, or three dimensions. The five-ply core-shell double gyroid phase was only found to be stable when the O+oxide domain was a minority. Removal of the polymer enabled simple and direct synthesis of mesoporous oxide materials while retaining the ordered network structure. We believe that advances in the synthesis of multi-ply nanocomposites will lead to advanced materials and devices containing multiple plies of functional materials.

Morphological Awareness and Children's Writing: Accuracy, Error, and Invention

PubMed Central

McCutchen, Deborah; Stull, Sara

2014-01-01

This study examined the relationship between children's morphological awareness and their ability to produce accurate morphological derivations in writing. Fifth-grade U.S. students (n = 175) completed two writing tasks that invited or required morphological manipulation of words. We examined both accuracy and error, specifically errors in spelling and errors of the sort we termed morphological inventions, which entailed inappropriate, novel pairings of stems and suffixes. Regressions were used to determine the relationship between morphological awareness, morphological accuracy, and spelling accuracy, as well as between morphological awareness and morphological inventions. Linear regressions revealed that morphological awareness uniquely predicted children's generation of accurate morphological derivations, regardless of whether or not accurate spelling was required. A logistic regression indicated that morphological awareness was also uniquely predictive of morphological invention, with higher morphological awareness increasing the probability of morphological invention. These findings suggest that morphological knowledge may not only assist children with spelling during writing, but may also assist with word production via generative experimentation with morphological rules during sentence generation. Implications are discussed for the development of children's morphological knowledge and relationships with writing. PMID:25663748

Neurogenesis-Promoting Natural Product α-Asarone Modulates Morphological Dynamics of Activated Microglia

PubMed Central

Cai, Qing; Li, Yuanyuan; Mao, Jianxin; Pei, Gang

2016-01-01

α-Asarone is an active constituent of Acori Tatarinowii, one of the widely used traditional Chinese Medicine to treat cognitive defect, and recently is shown to promote neurogenesis. Here, we demonstrated that low level (3 μM) of α-asarone attenuated LPS-induced BV2 cell bipolar elongated morphological change, with no significant effect on the LPS-induced pro-inflammatory cytokine expressions. In addition, time-lapse analysis also revealed that α-asarone modulated LPS-induced BV2 morphological dynamics. Consistently a significant reduction in the LPS-induced Monocyte Chemoattractant Protein (MCP-1) mRNA and protein levels was also detected along with the morphological change. Mechanistic study showed that the attenuation effect to the LPS-resulted morphological modulation was also detected in the presence of MCP-1 antibodies or a CCR2 antagonist. This result has also been confirmed in primary cultured microglia. The in vivo investigation provided further evidence that α-asarone reduced the proportion of activated microglia, and reduced microglial tip number and maintained the velocity. Our study thus reveals α-asarone effectively modulates microglial morphological dynamics, and implies this effect of α-asarone may functionally relate to its influence on neurogenesis. PMID:28018174

Transcriptional regulation of neuronal polarity and morphogenesis in the mammalian brain

PubMed Central

de la Torre-Ubieta, Luis; Bonni, Azad

2012-01-01

The highly specialized morphology of a neuron, typically consisting of a long axon and multiple branching dendrites, lies at the core of the principle of dynamic polarization, whereby information flows from dendrites toward the soma and to the axon. For more than a century neuroscientists have been fascinated by how shape is important for neuronal function and how neurons acquire their characteristic morphology. During the past decade, substantial progress has been made in our understanding of the molecular underpinnings of neuronal polarity and morphogenesis. In these studies, transcription factors have emerged as key players governing multiple aspects of neuronal morphogenesis from neuronal polarization and migration to axon growth and pathfinding to dendrite growth and branching to synaptogenesis. In this review, we will highlight the role of transcription factors in shaping neuronal morphology with emphasis on recent literature in mammalian systems. PMID:21982366

Hierarchical Cluster Analysis of Three-Dimensional Reconstructions of Unbiased Sampled Microglia Shows not Continuous Morphological Changes from Stage 1 to 2 after Multiple Dengue Infections in Callithrix penicillata

PubMed Central

Diniz, Daniel G.; Silva, Geane O.; Naves, Thaís B.; Fernandes, Taiany N.; Araújo, Sanderson C.; Diniz, José A. P.; de Farias, Luis H. S.; Sosthenes, Marcia C. K.; Diniz, Cristovam G.; Anthony, Daniel C.; da Costa Vasconcelos, Pedro F.; Picanço Diniz, Cristovam W.

2016-01-01

It is known that microglial morphology and function are related, but few studies have explored the subtleties of microglial morphological changes in response to specific pathogens. In the present report we quantitated microglia morphological changes in a monkey model of dengue disease with virus CNS invasion. To mimic multiple infections that usually occur in endemic areas, where higher dengue infection incidence and abundant mosquito vectors carrying different serotypes coexist, subjects received once a week subcutaneous injections of DENV3 (genotype III)-infected culture supernatant followed 24 h later by an injection of anti-DENV2 antibody. Control animals received either weekly anti-DENV2 antibodies, or no injections. Brain sections were immunolabeled for DENV3 antigens and IBA-1. Random and systematic microglial samples were taken from the polymorphic layer of dentate gyrus for 3-D reconstructions, where we found intense immunostaining for TNFα and DENV3 virus antigens. We submitted all bi- or multimodal morphological parameters of microglia to hierarchical cluster analysis and found two major morphological phenotypes designated types I and II. Compared to type I (stage 1), type II microglia were more complex; displaying higher number of nodes, processes and trees and larger surface area and volumes (stage 2). Type II microglia were found only in infected monkeys, whereas type I microglia was found in both control and infected subjects. Hierarchical cluster analysis of morphological parameters of 3-D reconstructions of random and systematic selected samples in control and ADE dengue infected monkeys suggests that microglia morphological changes from stage 1 to stage 2 may not be continuous. PMID:27047345

Hierarchical Cluster Analysis of Three-Dimensional Reconstructions of Unbiased Sampled Microglia Shows not Continuous Morphological Changes from Stage 1 to 2 after Multiple Dengue Infections in Callithrix penicillata.

PubMed

Diniz, Daniel G; Silva, Geane O; Naves, Thaís B; Fernandes, Taiany N; Araújo, Sanderson C; Diniz, José A P; de Farias, Luis H S; Sosthenes, Marcia C K; Diniz, Cristovam G; Anthony, Daniel C; da Costa Vasconcelos, Pedro F; Picanço Diniz, Cristovam W

2016-01-01

It is known that microglial morphology and function are related, but few studies have explored the subtleties of microglial morphological changes in response to specific pathogens. In the present report we quantitated microglia morphological changes in a monkey model of dengue disease with virus CNS invasion. To mimic multiple infections that usually occur in endemic areas, where higher dengue infection incidence and abundant mosquito vectors carrying different serotypes coexist, subjects received once a week subcutaneous injections of DENV3 (genotype III)-infected culture supernatant followed 24 h later by an injection of anti-DENV2 antibody. Control animals received either weekly anti-DENV2 antibodies, or no injections. Brain sections were immunolabeled for DENV3 antigens and IBA-1. Random and systematic microglial samples were taken from the polymorphic layer of dentate gyrus for 3-D reconstructions, where we found intense immunostaining for TNFα and DENV3 virus antigens. We submitted all bi- or multimodal morphological parameters of microglia to hierarchical cluster analysis and found two major morphological phenotypes designated types I and II. Compared to type I (stage 1), type II microglia were more complex; displaying higher number of nodes, processes and trees and larger surface area and volumes (stage 2). Type II microglia were found only in infected monkeys, whereas type I microglia was found in both control and infected subjects. Hierarchical cluster analysis of morphological parameters of 3-D reconstructions of random and systematic selected samples in control and ADE dengue infected monkeys suggests that microglia morphological changes from stage 1 to stage 2 may not be continuous.

Morphological changes during the life cycle of Aureobasidium pullulans (de Bary) Arnaud.

PubMed

Kocková-Kratochvílová, A; Cernáková, M; Sláviková, E

1980-01-01

Aureobasidium pullulans (de Bary) Arnaud was isolated from different natural materials plant blossoms in particular. Elements of vegetative multiplication, structure of colonies and cultures in liquid media were analyzed in detail, leading to construction of the life cycle of this organism. Morphological polymorphism was found to be combined with the production of melanin and the polysaccharide pullulan. Morphological analysis served for a directed selection for studies of physiological properties of this organism and its practical application.

Phonon Scattering in Silicon by Multiple Morphological Defects: A Multiscale Analysis

NASA Astrophysics Data System (ADS)

Lorenzi, Bruno; Dettori, Riccardo; Dunham, Marc T.; Melis, Claudio; Tonini, Rita; Colombo, Luciano; Sood, Aditya; Goodson, Kenneth E.; Narducci, Dario

2018-05-01

Ideal thermoelectric materials should possess low thermal conductivity κ along with high electrical conductivity σ . Thus, strategies are needed to impede the propagation of phonons mostly responsible for thermal conduction while only marginally affecting charge carrier diffusion. Defect engineering may provide tools to fulfill this aim, provided that one can achieve an adequate understanding of the role played by multiple morphological defects in scattering thermal energy carriers. In this paper, we study how various morphological defects such as grain boundaries and dispersed nanovoids reduce the thermal conductivity of silicon. A blended approach has been adopted, using data from both simulations and experiments in order to cover a wide range of defect densities. We show that the co-presence of morphological defects with different characteristic scattering length scales is effective in reducing the thermal conductivity. We also point out that non-gray models (i.e. models with spectral resolution) are required to improve the accuracy of predictive models explaining the dependence of κ on the density of morphological defects. Finally, the application of spectral models to Matthiessen's rule is critically addressed with the aim of arriving at a compact model of phonon scattering in highly defective materials showing that non-local descriptors would be needed to account for lattice distortion due to nanometric voids.

Docosapentaenoic acid (DPA) is a critical determinant of cubic membrane formation in amoeba Chaos mitochondria.

PubMed

Deng, Yuru; Almsherqi, Zakaria A; Shui, Guanghou; Wenk, Markus R; Kohlwein, Sepp D

2009-09-01

Very long-chain polyunsaturated fatty acids (VLC-PUFAs), such as docosahexaenoic acid (DHA) and docosapentaenoic acid (DPA), have recently made it to the realm of "magical molecules" based on their multiple presumably beneficial effects in biological systems, making these PUFAs particularly interesting in biomedicine. Their specific biological functions, however, remain enigmatic. Here we provide evidence derived from studies in the amoeba Chaos that indicates a structural role for omega-6 DPA in cell membrane organization, which may help to explain the multiple diverse effects of VLC-PUFA in healthy and diseased states. Amoeba Chaos mitochondria undergo a remarkable and reversible morphological transition into cubic morphology on starvation. This morphological transition is reflected in major changes in fatty acid and lipid composition, as determined by gas liquid chromatography and mass spectrometry, in particular by a drastic increase in C22:5 modified phosphatidylcholine plasmalogen, phosphatidylethanolamine plasmalogen, and phosphatidylinositol species. Liposomes produced in vitro from lipids of starved amoeba cells show a high propensity to form hexagonal tubular and cubic morphologies. Addition of omega-6 DPA, but not of omega-3 DPA, to the cell culture also induced mitochondrial membrane transformation into cubic morphology in fed cells, demonstrating for the first time an important structural role of omega-6 DPA-containing lipids in cell membrane organization.

Repeated Origin and Loss of Adhesive Toepads in Geckos

PubMed Central

Gamble, Tony; Greenbaum, Eli; Jackman, Todd R.; Russell, Anthony P.; Bauer, Aaron M.

2012-01-01

Geckos are well known for their extraordinary clinging abilities and many species easily scale vertical or even inverted surfaces. This ability is enabled by a complex digital adhesive mechanism (adhesive toepads) that employs van der Waals based adhesion, augmented by frictional forces. Numerous morphological traits and behaviors have evolved to facilitate deployment of the adhesive mechanism, maximize adhesive force and enable release from the substrate. The complex digital morphologies that result allow geckos to interact with their environment in a novel fashion quite differently from most other lizards. Details of toepad morphology suggest multiple gains and losses of the adhesive mechanism, but lack of a comprehensive phylogeny has hindered efforts to determine how frequently adhesive toepads have been gained and lost. Here we present a multigene phylogeny of geckos, including 107 of 118 recognized genera, and determine that adhesive toepads have been gained and lost multiple times, and remarkably, with approximately equal frequency. The most likely hypothesis suggests that adhesive toepads evolved 11 times and were lost nine times. The overall external morphology of the toepad is strikingly similar in many lineages in which it is independently derived, but lineage-specific differences are evident, particularly regarding internal anatomy, with unique morphological patterns defining each independent derivation. PMID:22761794

Secular trends in Cherokee cranial morphology: Eastern vs Western bands.

PubMed

Sutphin, Rebecca; Ross, Ann H; Jantz, Richard L

2014-01-01

The research objective was to examine if secular trends can be identified for cranial data commissioned by Boas in 1892, specifically for cranial breadth and cranial length of the Eastern and Western band Cherokee who experienced environmental hardships. Multiple regression analysis was used to test the degree of relationship between each of the cranial measures: cranial length, cranial breadth and cephalic index, along with predictor variables (year-of-birth, location, sex, admixture); the model revealed a significant difference for all craniometric variables. Additional regression analysis was performed with smoothing Loess plots to observe cranial length and cranial breadth change over time (year-of-birth) separately for Eastern and Western Cherokee band females and males born between 1783-1874. This revealed the Western and Eastern bands show a decrease in cranial length over time. Eastern band individuals maintain a relatively constant head breadth, while Western Band individuals show a sharp decline beginning around 1860. These findings support negative secular trend occurring for both Cherokee bands where the environment made a detrimental impact; this is especially marked with the Western Cherokee band.

Nannizziopsis guarroi infection in 2 Inland Bearded Dragons (Pogona vitticeps): clinical, cytologic, histologic, and ultrastructural aspects.

PubMed

Le Donne, Viviana; Crossland, Nicholas; Brandão, João; Sokolova, Yuliya; Fowlkes, Natalie; Nevarez, Javier G; Langohr, Ingeborg M; Gaunt, Stephen D

2016-06-01

Chrysosporium-related infections have been increasingly reported in reptiles over the last 2 decades. In this report, we describe clinical, cytologic, histopathologic, and ultrastructural aspects of Chrysosporium-related infection in 2 Inland Bearded Dragons (Pogona vitticeps). Case 1 was presented for an enlarging raised lesion over the left eye and multiple additional masses over the dorsum. Case 2 was submitted to necropsy by the referring veterinarian for suspected yellow fungus disease. Impression smears of the nodules in case 1 revealed granulomatous to pyogranulomatous inflammation and many septate, variably long, 4-10 μm wide, often undulated hyphae, and very rare conidia. Postmortem impression smears of the superficial lesions of case 2 contained large numbers of solitary conidia and arthroconidia and low numbers of hyphae with similar morphology to case 1. Histopathology of the 2 cases revealed severe, multifocal, chronic, ulcerative, nodular pyogranulomatous dermatitis, with myriad intralesional septate hyphae, and arthroconidia. Fungal culture and molecular sequencing in both cases indicated infection with Nannizziopsis guarroi. © 2016 American Society for Veterinary Clinical Pathology.

Computational Design of High-χ Block Oligomers for Accessing 1 nm Domains.

PubMed

Chen, Qile P; Barreda, Leonel; Oquendo, Luis E; Hillmyer, Marc A; Lodge, Timothy P; Siepmann, J Ilja

2018-05-22

Molecular dynamics simulations are used to design a series of high-χ block oligomers (HCBOs) that can self-assemble into a variety of mesophases with domain sizes as small as 1 nm. The exploration of these oligomers with various chain lengths, volume fractions, and chain architectures at multiple temperatures reveals the presence of ordered lamellae, perforated lamellae, and hexagonally packed cylinders. The achieved periods are as small as 3.0 and 2.1 nm for lamellae and cylinders, respectively, which correspond to polar domains of approximately 1 nm. Interestingly, the detailed phase behavior of these oligomers is distinct from that of either solvent-free surfactants or block polymers. The simulations reveal that the behavior of these HCBOs is a product of an interplay between both "surfactant factors" (headgroup interactions, chain flexibility, and interfacial curvature) and "block polymer factors" (χ, chain length N, and volume fraction f). This insight promotes the understanding of molecular features pivotal for mesophase formation at the sub-5 nm length scale, which facilitates the design of HCBOs tailored toward particular desired morphologies.

Characterization of Induced Pluripotent Stem Cell Microvesicle Genesis, Morphology and Pluripotent Content

PubMed Central

Zhou, Jing; Ghoroghi, Shima; Benito-Martin, Alberto; Wu, Hao; Unachukwu, Uchenna John; Einbond, Linda Saxe; Guariglia, Sara; Peinado, Hector; Redenti, Stephen

2016-01-01

Microvesicles (MVs) are lipid bilayer-covered cell fragments that range in diameter from 30 nm–1uM and are released from all cell types. An increasing number of studies reveal that MVs contain microRNA, mRNA and protein that can be detected in the extracellular space. In this study, we characterized induced pluripotent stem cell (iPSC) MV genesis, content and fusion to retinal progenitor cells (RPCs) in vitro. Nanoparticle tracking revealed that iPSCs released approximately 2200 MVs cell/hour in the first 12 hrs with an average diameter of 122 nm. Electron and light microscopic analysis of iPSCs showed MV release via lipid bilayer budding. The mRNA content of iPSC MVs was characterized and revealed the presence of the transcription factors Oct-3/4, Nanog, Klf4, and C-Myc. The protein content of iPSCs MVs, detected by immunogold electron microscopy, revealed the presence of the Oct-3/4 and Nanog. Isolated iPSC MVs were shown to fuse with RPCs in vitro at multiple points along the plasma membrane. These findings demonstrate that the mRNA and protein cargo in iPSC MVs have established roles in maintenance of pluripotency. Building on this work, iPSC derived MVs may be shown to be involved in maintaining cellular pluripotency and may have application in regenerative strategies for neural tissue. PMID:26797168

On the polymorphic and morphological changes of cellulose nanocrystals (CNC-I) upon mercerization and conversion to CNC-II.

PubMed

Jin, Ersuo; Guo, Jiaqi; Yang, Fang; Zhu, Yangyang; Song, Junlong; Jin, Yongcan; Rojas, Orlando J

2016-06-05

Polymorphic and morphological transformations of cellulosic materials are strongly associated to their properties and applications, especially in the case of emerging nanocelluloses. Related changes that take place upon treatment of cellulose nanocrystals (CNC) in alkaline conditions are studied here by XRD, TEM, AFM, and other techniques. The results indicate polymorphic transformation of CNC proceeds gradually in a certain range of alkali concentrations, i.e. from about 8% to 12.5% NaOH. In such transition alkali concentration, cellulose I and II allomorphs coexists. Such value and range of the transition concentration is strongly interdependent with the crystallite size of CNCs. In addition, it is distinctively lower than that for macroscopic fibers (12-15% NaOH). Transmission electron microscopy and particle sizing reveals that after mercerization CNCs tend to associate. Furthermore, TEMPO-oxidized mercerized CNC reveals the morphology of individual nanocrystal of the cellulose II type, which is composed of some interconnected granular structures. Overall, this work reveals how the polymorphism and morphology of individual CNC change in alkali conditions and sheds light onto the polymorphic transition from cellulose I to II. Copyright © 2016 Elsevier Ltd. All rights reserved.

Further study on Physaloptera clausa Rudolphi, 1819 (Spirurida: Physalopteridae) from the Amur hedgehog Erinaceus amurensis Schrenk (Eulipotyphla: Erinaceidae).

PubMed

Chen, Hui-Xia; Ju, Hui-Dong; Li, Yang; Li, Liang

2017-12-20

In the present study, light and scanning electron microscopy (SEM) were used to further study the detailed morphology of Physaloptera clausa Rudolphi, 1819, based on the material collected from the Amur hedgehog E. amurensis Schrenk in China. The results revealed a few previously unreported morphological features and some morphological and morphometric variability between our specimens and the previous studies. The present supplementary morphological characters and morphometric data could help us to recognize this species more accurately.

Allocation, morphology, physiology, architecture: the multiple facets of plant above- and below-ground responses to resource stress.

PubMed

Freschet, Grégoire T; Violle, Cyrille; Bourget, Malo Y; Scherer-Lorenzen, Michael; Fort, Florian

2018-06-01

Plants respond to resource stress by changing multiple aspects of their biomass allocation, morphology, physiology and architecture. To date, we lack an integrated view of the relative importance of these plastic responses in alleviating resource stress and of the consistency/variability of these responses among species. We subjected nine species (legumes, forbs and graminoids) to nitrogen and/or light shortages and measured 11 above-ground and below-ground trait adjustments critical in the alleviation of these stresses (plus several underlying traits). Nine traits out of 11 showed adjustments that improved plants' potential capacity to acquire the limiting resource at a given time. Above ground, aspects of plasticity in allocation, morphology, physiology and architecture all appeared important in improving light capture, whereas below ground, plasticity in allocation and physiology were most critical to improving nitrogen acquisition. Six traits out of 11 showed substantial heterogeneity in species plasticity, with little structuration of these differences within trait covariation syndromes. Such comprehensive assessment of the complex nature of phenotypic responses of plants to multiple stress factors, and the comparison of plant responses across multiple species, makes a clear case for the high (but largely overlooked) diversity of potential plastic responses of plants, and for the need to explore the potential rules structuring them. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

Method of making controlled morphology metal-oxides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ozcan, Soydan; Lu, Yuan

2016-05-17

A method of making metal oxides having a preselected morphology includes preparing a suspension that includes a solvent, polymeric nanostructures having multiplicities of hydroxyl surface groups and/or carboxyl surface groups, and a metal oxide precursor. The suspension has a preselected ratio of the polymeric nanostructures to the metal oxide precursor of at least 1:3, the preselected ratio corresponding to a preselected morphology. Subsequent steps include depositing the suspension onto a substrate, removing the solvent to form a film, removing the film from the substrate, and annealing the film to volatilize the polymeric nanostructures and convert the metal oxide precursor tomore » metal oxide nanoparticles having the preselected morphology or to a metal oxide nanosheet including conjoined nanoparticles having the preselected morphology.« less

Removing impulse bursts from images by training-based soft morphological filtering

NASA Astrophysics Data System (ADS)

Koivisto, Pertti T.; Astola, Jaakko T.; Lukin, Vladimir V.; Melnik, Vladimir P.; Tsymbal, Oleg V.

2001-08-01

The characteristics of impulse bursts in radar images are analyzed and a model for this noise is proposed. The model also takes into consideration the multiplicative noise present in radar images. As a case study, soft morphological filters utilizing a training-based optimization scheme are used for the noise removal. Different approaches for the training are discussed. It is shown that the methods used can provide an effective removal of impulse bursts. At the same time the multiplicative noise in images is also suppressed together with god edge and detail preservation. Numerical simulation results as well as examples of real radar images are presented.

Structural analysis of respiratory syncytial virus reveals the position of M2-1 between the matrix protein and the ribonucleoprotein complex.

PubMed

Kiss, Gabriella; Holl, Jens M; Williams, Grant M; Alonas, Eric; Vanover, Daryll; Lifland, Aaron W; Gudheti, Manasa; Guerrero-Ferreira, Ricardo C; Nair, Vinod; Yi, Hong; Graham, Barney S; Santangelo, Philip J; Wright, Elizabeth R

2014-07-01

Respiratory syncytial virus (RSV), a member of the Paramyxoviridae family of nonsegmented, negative-sense, single-stranded RNA genome viruses, is a leading cause of lower respiratory tract infections in infants, young children, and the elderly or immunocompromised. There are many open questions regarding the processes that regulate human RSV (hRSV) assembly and budding. Here, using cryo-electron tomography, we identified virus particles that were spherical, filamentous, and asymmetric in structure, all within the same virus preparation. The three particle morphologies maintained a similar organization of the surface glycoproteins, matrix protein (M), M2-1, and the ribonucleoprotein (RNP). RNP filaments were traced in three dimensions (3D), and their total length was calculated. The measurements revealed the inclusion of multiple full-length genome copies per particle. RNP was associated with the membrane whenever the M layer was present. The amount of M coverage ranged from 24% to 86% in the different morphologies. Using fluorescence light microscopy (fLM), direct stochastic optical reconstruction microscopy (dSTORM), and a proximity ligation assay (PLA), we provide evidence illustrating that M2-1 is located between RNP and M in isolated viral particles. In addition, regular spacing of the M2-1 densities was resolved when hRSV viruses were imaged using Zernike phase contrast (ZPC) cryo-electron tomography. Our studies provide a more complete characterization of the hRSV virion structure and substantiation that M and M2-1 regulate virus organization. hRSV is a leading cause of lower respiratory tract infections in infants and young children as well as elderly or immunocompromised individuals. We used cryo-electron tomography and Zernike phase contrast cryo-electron tomography to visualize populations of purified hRSV in 3D. We observed the three distinct morphologies, spherical, filamentous, and asymmetric, which maintained comparable organizational profiles. Depending on the virus morphology examined, the amount of M ranged from 24% to 86%. We complemented the cryo-imaging studies with fluorescence microscopy, dSTORM, and a proximity ligation assay to provide additional evidence that M2-1 is incorporated into viral particles and is positioned between M and RNP. The results highlight the impact of M and M2-1 on the regulation of hRSV organization. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Modeling non-syndromic autism and the impact of TRPC6 disruption in human neurons.

PubMed

Griesi-Oliveira, K; Acab, A; Gupta, A R; Sunaga, D Y; Chailangkarn, T; Nicol, X; Nunez, Y; Walker, M F; Murdoch, J D; Sanders, S J; Fernandez, T V; Ji, W; Lifton, R P; Vadasz, E; Dietrich, A; Pradhan, D; Song, H; Ming, G-L; Gu, X; Haddad, G; Marchetto, M C N; Spitzer, N; Passos-Bueno, M R; State, M W; Muotri, A R

2015-11-01

An increasing number of genetic variants have been implicated in autism spectrum disorders (ASDs), and the functional study of such variants will be critical for the elucidation of autism pathophysiology. Here, we report a de novo balanced translocation disruption of TRPC6, a cation channel, in a non-syndromic autistic individual. Using multiple models, such as dental pulp cells, induced pluripotent stem cell (iPSC)-derived neuronal cells and mouse models, we demonstrate that TRPC6 reduction or haploinsufficiency leads to altered neuronal development, morphology and function. The observed neuronal phenotypes could then be rescued by TRPC6 complementation and by treatment with insulin-like growth factor-1 or hyperforin, a TRPC6-specific agonist, suggesting that ASD individuals with alterations in this pathway may benefit from these drugs. We also demonstrate that methyl CpG binding protein-2 (MeCP2) levels affect TRPC6 expression. Mutations in MeCP2 cause Rett syndrome, revealing common pathways among ASDs. Genetic sequencing of TRPC6 in 1041 ASD individuals and 2872 controls revealed significantly more nonsynonymous mutations in the ASD population, and identified loss-of-function mutations with incomplete penetrance in two patients. Taken together, these findings suggest that TRPC6 is a novel predisposing gene for ASD that may act in a multiple-hit model. This is the first study to use iPSC-derived human neurons to model non-syndromic ASD and illustrate the potential of modeling genetically complex sporadic diseases using such cells.

Modeling non-syndromic autism and the impact of TRPC6 disruption in human neurons

PubMed Central

Griesi-Oliveira, Karina; Acab, Allan; Gupta, Abha R.; Sunaga, Daniele Yumi; Chailangkarn, Thanathom; Nicol, Xavier; Nunez, Yanelli; Walker, Michael F.; Murdoch, John D.; Sanders, Stephan J.; Fernandez, Thomas V.; Ji, Weizhen; Lifton, Richard P.; Vadasz, Estevão; Dietrich, Alexander; Pradhan, Dennis; Song, Hongjun; Ming, Guo-li; Guoe, Xiang; Haddad, Gabriel; Marchetto, Maria C. N.; Spitzer, Nicholas; Passos-Bueno, Maria Rita; State, Matthew W.; Muotri, Alysson R.

2014-01-01

An increasing number of genetic variants have been implicated in autism spectrum disorders (ASD), and the functional study of such variants will be critical for the elucidation of autism pathophysiology. Here, we report a de novo balanced translocation disruption of TRPC6, a cation channel, in a non-syndromic autistic individual. Using multiple models, such as dental pulp cells, iPSC-derived neuronal cells and mouse models, we demonstrate that TRPC6 reduction or haploinsufficiency leads to altered neuronal development, morphology, and function. The observed neuronal phenotypes could then be rescued by TRPC6 complementation and by treatment with IGF1 or hyperforin, a TRPC6-specific agonist, suggesting that ASD individuals with alterations in this pathway might benefit from these drugs. We also demonstrate that MeCP2 levels affect TRPC6 expression. Mutations in MeCP2 cause Rett syndrome, revealing common pathways among ASDs. Genetic sequencing of TRPC6 in 1041 ASD individuals and 2872 controls revealed significantly more nonsynonymous mutations in the ASD population, and identified loss-of-function mutations with incomplete penetrance in two patients. Taken together, these findings suggest that TRPC6 is a novel predisposing gene for ASD that may act in a multiple-hit model. This is the first study to use iPSC-derived human neurons to model non-syndromic ASD and illustrate the potential of modeling genetically complex sporadic diseases using such cells. PMID:25385366

Adaptation Genomics of a Small-Colony Variant in a Pseudomonas chlororaphis 30-84 Biofilm

PubMed Central

Dorosky, Robert J.; Han, Cliff S.; Lo, Chien-chi; Dichosa, Armand E. K.; Chain, Patrick S.; Yu, Jun Myoung; Pierson, Leland S.

2014-01-01

The rhizosphere-colonizing bacterium Pseudomonas chlororaphis 30-84 is an effective biological control agent against take-all disease of wheat. In this study, we characterize a small-colony variant (SCV) isolated from a P. chlororaphis 30-84 biofilm. The SCV exhibited pleiotropic phenotypes, including small cell size, slow growth and motility, low levels of phenazine production, and increased biofilm formation and resistance to antimicrobials. To better understand the genetic alterations underlying these phenotypes, RNA and whole-genome sequencing analyses were conducted comparing an SCV to the wild-type strain. Of the genome's 5,971 genes, transcriptomic profiling indicated that 1,098 (18.4%) have undergone substantial reprograming of gene expression in the SCV. Whole-genome sequence analysis revealed multiple alterations in the SCV, including mutations in yfiR (cyclic-di-GMP production), fusA (elongation factor), and cyoE (heme synthesis) and a 70-kb deletion. Genetic analysis revealed that the yfiR locus plays a major role in controlling SCV phenotypes, including colony size, growth, motility, and biofilm formation. Moreover, a point mutation in the fusA gene contributed to kanamycin resistance. Interestingly, the SCV can partially switch back to wild-type morphologies under specific conditions. Our data also support the idea that phenotypic switching in P. chlororaphis is not due to simple genetic reversions but may involve multiple secondary mutations. The emergence of these highly adherent and antibiotic-resistant SCVs within the biofilm might play key roles in P. chlororaphis natural persistence. PMID:25416762

Decomposition into Multiple Morphemes during Lexical Access: A Masked Priming Study of Russian Nouns

ERIC Educational Resources Information Center

Kazanina, Nina; Dukova-Zheleva, Galina; Geber, Dana; Kharlamov, Viktor; Tonciulescu, Keren

2008-01-01

The study reports the results of a masked priming experiment with morphologically complex Russian nouns. Participants performed a lexical decision task to a visual target that differed from its prime in one consonant. Three conditions were included: (1) "transparent," in which the prime was morphologically related to the target and contained the…

Morphological Awareness in Vocabulary Acquisition among Chinese-Speaking Children: Testing Partial Mediation via Lexical Inference Ability

ERIC Educational Resources Information Center

Zhang, Haomin

2015-01-01

The goal of this study was to investigate the effect of Chinese-specific morphological awareness on vocabulary acquisition among young Chinese-speaking students. The participants were 288 Chinese-speaking second graders from three different cities in China. Multiple regression analysis and mediation analysis were used to uncover the mediated and…

Charge transport in CdTe solar cells revealed by conductive tomographic atomic force microscopy

DOE PAGES

Luria, Justin; Kutes, Yasemin; Moore, Andrew; ...

2016-09-26

Polycrystalline photovoltaics comprising cadmium telluride (CdTe) represent a growing portion of the solar cell market, yet the physical picture of charge transport through the meso-scale grain morphology remains a topic of debate. It is unknown how thin film morphology affects the transport of electron-hole pairs. Accordingly this study is the first to generate three dimensional images of photocurrent throughout a thin-film solar cell, revealing the profound influence of grain boundaries and stacking faults on device efficiency.

Morphology and FT IR spectra of porous silicon

NASA Astrophysics Data System (ADS)

Kopani, Martin; Mikula, Milan; Kosnac, Daniel; Gregus, Jan; Pincik, Emil

2017-12-01

The morphology and chemical bods of p-type and n-type porous Si was compared. The surface of n-type sample is smooth, homogenous without any features. The surface of p-type sample reveals micrometer-sized islands. FTIR investigation reveals various distribution of SiOxHy complexes in both p-and n-type samples. From the conditions leading to porous silicon layer formation (the presence of holes) we suggest both SiOxHy and SiFxHy complexes in the layer.

Lexicality, Morphological Structure, and Semantic Transparency in the Processing of German Ver-Verbs: The Complementarity of On-Line and Off-Line Evidence

ERIC Educational Resources Information Center

Schirmeier, Matthias K.; Derwing, Bruce L.; Libben, Gary

2004-01-01

Two types of experiments investigate the visual on-line and off-line processing of German ver-verbs (e.g., verbittern "to embitte"). In Experiments 1 and 2 (morphological priming), latency patterns revealed the existence of facilitation effects for the morphological conditions (BITTER-VERBITTERN and BITTERN-VERBITTERN) as compared to the neutral…

Evaluating the Morphology of the Local Interstellar Medium: Using New Data to Distinguish between Multiple Discrete Clouds and a Continuous Medium

NASA Astrophysics Data System (ADS)

Redfield, Seth; Linsky, Jeffrey L.

2015-10-01

Ultraviolet and optical spectra of interstellar gas along the lines of sight to nearby stars have been interpreted by Redfield & Linsky and previous studies as a set of discrete warm, partially ionized clouds each with a different flow vector, temperature, and metal depletion. Recently, Gry & Jenkins proposed a fundamentally different model consisting of a single cloud with nonrigid flows filling space out to 9 pc from the Sun that they propose better describes the local ISM. Here we test these fundamentally different morphological models against the spatially unbiased Malamut et al. spectroscopic data set, and find that the multiple cloud morphology model provides a better fit to both the new and old data sets. The detection of three or more velocity components along the lines of sight to many nearby stars, the presence of nearby scattering screens, the observed thin elongated structures of warm interstellar gas, and the likely presence of strong interstellar magnetic fields also support the multiple cloud model. The detection and identification of intercloud gas and the measurement of neutral hydrogen density in clouds beyond the Local Interstellar Cloud could provide future morphological tests. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the Data Archive at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS AR-09525.01A. These observations are associated with programs #11568.

[Focal lymphoid hyperplasia (pseudolymphoma) of the terminal ileum in adults].

PubMed

Molas, G; Potet, F; Nogig, P

1985-01-01

We report two cases of focal lymphoid hyperplasia (FLH) of terminal ileum in adult patients. Both cases showed identical morphological findings. The first was discovered during cholecystectomy in a 75-year-old woman who complained mild non-specific abdominal discomfort. The second was manifested by right lower quadrant abdominal pain in a 32-year-old man. The surgical specimens revealed a thickened wall, a narrowed lumen and multiple ulcerations. The histologic features were small cell, well differentiated lymphocyte infiltration, with several follicles showing large germinal centers; regional lymph nodes revealed a conspicuous reactive size enlargement. Further clinical investigations revealed no other abnormalities. Clinical course showed benign evolution after 6 and 3 years of respective follow-up. FLH should be differentiated from terminal ileum inflammatory and infectious diseases. It can be differentiated from Crohn's disease by the absence of characteristic histological features; from Yersinia infection by the absence of significant rates of specific serum antibodies. Moreover, FLH can be differentiated from malignant lymphoma by the presence of follicles and enlarged germinal centers and by the long-term benign evolution. The nature of FLH in terminal ileum, as well as those of the stomach and colo-rectum is still to be determined. Several hypothesis are proposed: reactive, benign neoplastic, or prelymphomatous lesion?

Preservation of Late Amazonian Mars ice and water-related deposits in a unique crater environment in Noachis Terra: Age relationships between lobate debris tongues and gullies

NASA Astrophysics Data System (ADS)

Morgan, Gareth A.; Head, James W.; Marchant, David R.

2011-01-01

The Amazonian period of Mars has been described as static, cold, and dry. Recent analysis of high-resolution imagery of equatorial and mid-latitude regions has revealed an array of young landforms produced in association with ice and liquid water; because near-surface ice in these regions is currently unstable, these ice-and-water-related landforms suggest one or more episodes of martian climate change during the Amazonian. Here we report on the origin and evolution of valley systems within a degraded crater in Noachis Terra, Asimov Crater. The valleys have produced a unique environment in which to study the geomorphic signals of Amazonian climate change. New high-resolution images reveal Hesperian-aged layered basalt with distinctive columnar jointing capping interior crater fill and providing debris, via mass wasting, for the surrounding annular valleys. The occurrence of steep slopes (>20°), relatively narrow (sheltered) valleys, and a source of debris have provided favorable conditions for the preservation of shallow-ice deposits. Detailed mapping reveals morphological evidence for viscous ice flow, in the form of several lobate debris tongues (LDT). Superimposed on LDT are a series of fresh-appearing gullies, with typical alcove, channel, and fan morphologies. The shift from ice-rich viscous-flow formation to gully erosion is best explained as a shift in martian climate, from one compatible with excess snowfall and flow of ice-rich deposits, to one consistent with minor snow and gully formation. Available dating suggests that the climate transition occurred >8 Ma, prior to the formation of other small-scale ice-rich flow features identified elsewhere on Mars that have been interpreted to have formed during the most recent phases of high obliquity. Taken together, these older deposits suggest that multiple climatic shifts have occurred over the last tens of millions of years of martian history.

Geometric analysis of Arabidopsis root apex reveals a new aspect of the ethylene signal transduction pathway in development

NASA Technical Reports Server (NTRS)

Cervantes, Emilio; Tocino, Angel

2005-01-01

Structurally, ethylene is the simplest phytohormone and regulates multiple aspects of plant growth and development. Its effects are mediated by a signal transduction cascade involving receptors, MAP kinases and transcription factors. Many morphological effects of ethylene in plant development, including root size, have been previously described. In this article a combined geometric and algebraic approach has been used to analyse the shape and the curvature in the root apex of Arabidopsis seedlings. The process requires the fitting of Bezier curves that reproduce the root apex shape, and the calculation of the corresponding curvatures. The application of the method has allowed us to identify significant differences in the root curvatures of ethylene insensitive mutants (ein2-1 and etr1-1) with respect to the wild-type Columbia.

Integrated Analyses Resolve Conflicts over Squamate Reptile Phylogeny and Reveal Unexpected Placements for Fossil Taxa

PubMed Central

Reeder, Tod W.; Townsend, Ted M.; Mulcahy, Daniel G.; Noonan, Brice P.; Wood, Perry L.; Sites, Jack W.; Wiens, John J.

2015-01-01

Squamate reptiles (lizards and snakes) are a pivotal group whose relationships have become increasingly controversial. Squamates include >9000 species, making them the second largest group of terrestrial vertebrates. They are important medicinally and as model systems for ecological and evolutionary research. However, studies of squamate biology are hindered by uncertainty over their relationships, and some consider squamate phylogeny unresolved, given recent conflicts between molecular and morphological results. To resolve these conflicts, we expand existing morphological and molecular datasets for squamates (691 morphological characters and 46 genes, for 161 living and 49 fossil taxa, including a new set of 81 morphological characters and adding two genes from published studies) and perform integrated analyses. Our results resolve higher-level relationships as indicated by molecular analyses, and reveal hidden morphological support for the molecular hypothesis (but not vice-versa). Furthermore, we find that integrating molecular, morphological, and paleontological data leads to surprising placements for two major fossil clades (Mosasauria and Polyglyphanodontia). These results further demonstrate the importance of combining fossil and molecular information, and the potential problems of estimating the placement of fossil taxa from morphological data alone. Thus, our results caution against estimating fossil relationships without considering relevant molecular data, and against placing fossils into molecular trees (e.g. for dating analyses) without considering the possible impact of molecular data on their placement. PMID:25803280

Integrated analyses resolve conflicts over squamate reptile phylogeny and reveal unexpected placements for fossil taxa.

PubMed

Reeder, Tod W; Townsend, Ted M; Mulcahy, Daniel G; Noonan, Brice P; Wood, Perry L; Sites, Jack W; Wiens, John J

2015-01-01

Squamate reptiles (lizards and snakes) are a pivotal group whose relationships have become increasingly controversial. Squamates include >9000 species, making them the second largest group of terrestrial vertebrates. They are important medicinally and as model systems for ecological and evolutionary research. However, studies of squamate biology are hindered by uncertainty over their relationships, and some consider squamate phylogeny unresolved, given recent conflicts between molecular and morphological results. To resolve these conflicts, we expand existing morphological and molecular datasets for squamates (691 morphological characters and 46 genes, for 161 living and 49 fossil taxa, including a new set of 81 morphological characters and adding two genes from published studies) and perform integrated analyses. Our results resolve higher-level relationships as indicated by molecular analyses, and reveal hidden morphological support for the molecular hypothesis (but not vice-versa). Furthermore, we find that integrating molecular, morphological, and paleontological data leads to surprising placements for two major fossil clades (Mosasauria and Polyglyphanodontia). These results further demonstrate the importance of combining fossil and molecular information, and the potential problems of estimating the placement of fossil taxa from morphological data alone. Thus, our results caution against estimating fossil relationships without considering relevant molecular data, and against placing fossils into molecular trees (e.g. for dating analyses) without considering the possible impact of molecular data on their placement.

Sex-specific Effects of Exercise Ancestry on Metabolic, Morphological, and Gene Expression Phenotypes in Multiple Generations of Mouse Offspring

PubMed Central

Guth, Lisa M.; Ludlow, Andrew T.; Witkowski, Sarah; Marshall, Mallory R.; Lima, Laila C. J.; Venezia, Andrew C.; Xiao, Tao; Lee, Mei-Ling Ting; Spangenburg, Espen E.; Roth, Stephen M.

2013-01-01

Early life and pre-conception environmental stimuli can affect adult health-related phenotypes. Exercise training is an environmental stimulus affecting many systems throughout the body and appears to alter offspring phenotypes. The aim of this study was to examine the influence of parental exercise training, or “exercise ancestry,” on morphological and metabolic phenotypes in two generations of mouse offspring. F0 C57BL/6 mice were exposed to voluntary exercise or sedentary lifestyle and bred with like-exposed mates to produce an F1 generation. F1 mice of both ancestries were sedentary and sacrificed at 8 wk or bred with littermates to produce an F2 generation, which was also sedentary and sacrificed at 8 wk. Small, but broad generation- and sex-specific effects of exercise ancestry were observed for body mass, fat and muscle mass, serum insulin, glucose tolerance, and muscle gene expression. F1 EX females were lighter than F1 SED females, and had lower absolute tibialis anterior and omental fat masses. Serum insulin was higher in F1 EX females compared to F1 SED females. F2 EX females had impaired glucose tolerance compared to F2 SED females. Analysis of skeletal muscle mRNA levels revealed several generation- and sex-specific differences in mRNA levels for multiple genes, especially those related to metabolic genes (e.g., F1 EX males had lower mRNA levels of Hk2, Ppard, Ppargc1α, Adipoq, and Scd1 than F1 SED males). These results provide preliminary evidence that parental exercise training can influence health-related phenotypes in mouse offspring. PMID:23771910

CSI 2264: simultaneous optical and infrared light curves of young disk-bearing stars in NGC 2264 with CoRoT and Spitzer—evidence for multiple origins of variability

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cody, Ann Marie; Stauffer, John; Rebull, Luisa M.

2014-04-01

We present the Coordinated Synoptic Investigation of NGC 2264, a continuous 30 day multi-wavelength photometric monitoring campaign on more than 1000 young cluster members using 16 telescopes. The unprecedented combination of multi-wavelength, high-precision, high-cadence, and long-duration data opens a new window into the time domain behavior of young stellar objects. Here we provide an overview of the observations, focusing on results from Spitzer and CoRoT. The highlight of this work is detailed analysis of 162 classical T Tauri stars for which we can probe optical and mid-infrared flux variations to 1% amplitudes and sub-hour timescales. We present a morphological variabilitymore » census and then use metrics of periodicity, stochasticity, and symmetry to statistically separate the light curves into seven distinct classes, which we suggest represent different physical processes and geometric effects. We provide distributions of the characteristic timescales and amplitudes and assess the fractional representation within each class. The largest category (>20%) are optical 'dippers' with discrete fading events lasting ∼1-5 days. The degree of correlation between the optical and infrared light curves is positive but weak; notably, the independently assigned optical and infrared morphology classes tend to be different for the same object. Assessment of flux variation behavior with respect to (circum)stellar properties reveals correlations of variability parameters with Hα emission and with effective temperature. Overall, our results point to multiple origins of young star variability, including circumstellar obscuration events, hot spots on the star and/or disk, accretion bursts, and rapid structural changes in the inner disk.« less

Absence of CFAP69 Causes Male Infertility due to Multiple Morphological Abnormalities of the Flagella in Human and Mouse.

PubMed

Dong, Frederick N; Amiri-Yekta, Amir; Martinez, Guillaume; Saut, Antoine; Tek, Julie; Stouvenel, Laurence; Lorès, Patrick; Karaouzène, Thomas; Thierry-Mieg, Nicolas; Satre, Véronique; Brouillet, Sophie; Daneshipour, Abbas; Hosseini, Seyedeh Hanieh; Bonhivers, Mélanie; Gourabi, Hamid; Dulioust, Emmanuel; Arnoult, Christophe; Touré, Aminata; Ray, Pierre F; Zhao, Haiqing; Coutton, Charles

2018-04-05

The multiple morphological abnormalities of the flagella (MMAF) phenotype is among the most severe forms of sperm defects responsible for male infertility. The phenotype is characterized by the presence in the ejaculate of immotile spermatozoa with severe flagellar abnormalities including flagella being short, coiled, absent, and of irregular caliber. Recent studies have demonstrated that MMAF is genetically heterogeneous, and genes thus far associated with MMAF account for only one-third of cases. Here we report the identification of homozygous truncating mutations (one stop-gain and one splicing variant) in CFAP69 of two unrelated individuals by whole-exome sequencing of a cohort of 78 infertile men with MMAF. CFAP69 encodes an evolutionarily conserved protein found at high levels in the testis. Immunostaining experiments in sperm from fertile control individuals showed that CFAP69 localized to the midpiece of the flagellum, and the absence of CFAP69 was confirmed in both individuals carrying CFPA69 mutations. Additionally, we found that sperm from a Cfap69 knockout mouse model recapitulated the MMAF phenotype. Ultrastructural analysis of testicular sperm from the knockout mice showed severe disruption of flagellum structure, but histological analysis of testes from these mice revealed the presence of all stages of the seminiferous epithelium, indicating that the overall progression of spermatogenesis is preserved and that the sperm defects likely arise during spermiogenesis. Together, our data indicate that CFAP69 is necessary for flagellum assembly/stability and that in both humans and mice, biallelic truncating mutations in CFAP69 cause autosomal-recessive MMAF and primary male infertility. Copyright © 2018 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

The phylogeny of brown lacewings (Neuroptera: Hemerobiidae) reveals multiple reductions in wing venation.

PubMed

Garzón-Orduña, Ivonne J; Menchaca-Armenta, Imelda; Contreras-Ramos, Atilano; Liu, Xingyue; Winterton, Shaun L

2016-09-20

The last time the phylogenetic relationships among members of the family Hemerobiidae were studied quantitatively was over 12 years ago and based exclusively on morphology. Our study builds upon this morphological evidence by adding sequence data from three gene loci to provide a total evidence phylogeny of brown lacewings (Neuroptera: Hemerobiidae). Thirty-seven species representing nineteen Hemerobiidae genera were compared with outgroups from the families Ithonidae, Psychopsidae and Chrysopidae in Bayesian and parsimony analyses using a single nuclear gene (CAD) and two mitochondrial (16S rDNA and Cytochrome Oxidase I) genes. We compare divergence time estimates of Hemerobiidae cladogenesis under the two most commonly used relaxed clock models and discuss the evolution of wing venation in the family. We recovered a phylogeny largely incongruent with previously published morphological studies, although all but two subfamilies (i.e., Notiobiellinae and Drepanacrinae) were recovered as monophyletic. We found the subfamily Drepanacrinae paraphyletic with respect to Psychobiellinae, and Notiobiellinae to be polyphyletic. We thus offer a revised concept of Notiobiellinae, comprising only Notiobiella Banks, and erect a new subfamily Zachobiellinae including the remaining genera previously placed in Notiobiellinae. Psychobiellinae is synonymized with Drepanacrinae. Unlike the previous hypothesis that proposed a remarkably laddered topology, our tree suggests that hemerobiids diverged as three main clades. Moreover, in contrast to the vein proliferation hypothesis, we found that hemerobiids have instead undergone multiple reductions in the number of radial veins, this scenario questions the relevance of this character as diagnostic of various subfamilies Our phylogenetic hypothesis and divergence times analysis suggest that extant hemerobiids originated around the end of the Triassic and evolved as three distinct clades that diverged from one another during the Late Jurassic to Early Cretaceous. Contrary to earlier phylogenetic hypotheses, Carobius Banks (Carobiinae) is sister to the previously unplaced genus Notherobius New in a clade more closely related to Sympherobiinae, Megalominae and Zachobiellinae subfam. nov. The addition of taxa which are not available for DNA sequencing should be the focus of future studies, especially Adelphohemerobius Oswald, which is particularly important to test our inferences regarding the evolution of wing venation in Hemerobiidae.

Effect of captivity on morphology: negligible changes in external morphology mask significant changes in internal morphology

PubMed Central

Munn, Adam J.; Byrne, Phillip G.

2018-01-01

Captive breeding programmes are increasingly relied upon for threatened species management. Changes in morphology can occur in captivity, often with unknown consequences for reintroductions. Few studies have examined the morphological changes that occur in captive animals compared with wild animals. Further, the effect of multiple generations being maintained in captivity, and the potential effects of captivity on sexual dimorphism remain poorly understood. We compared external and internal morphology of captive and wild animals using house mouse (Mus musculus) as a model species. In addition, we looked at morphology across two captive generations, and compared morphology between sexes. We found no statistically significant differences in external morphology, but after one generation in captivity there was evidence for a shift in the internal morphology of captive-reared mice; captive-reared mice (two generations bred) had lighter combined kidney and spleen masses compared with wild-caught mice. Sexual dimorphism was maintained in captivity. Our findings demonstrate that captive breeding can alter internal morphology. Given that these morphological changes may impact organismal functioning and viability following release, further investigation is warranted. If the morphological change is shown to be maladaptive, these changes would have significant implications for captive-source populations that are used for reintroduction, including reduced survivorship.

Mechanical, thermal, morphological, and rheological characteristics of high performance 3D-printing lignin-based composites for additive manufacturing applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nguyen, Ngoc A.; Bowland, Christopher C.; Naskar, Amit K.

Here, the article presents different mechanical, thermal and rheological data corresponding to the morphological formation within various renewable lignin-based composites containing acrylonitrile butadiene styrene (ABS), acrylonitrile butadiene rubber (NBR41, 41 mol% nitrile content), and carbon fibers (CFs). The data of 3D-printing properties and morphology of 3D-printed layers of selected lignin-based composites are revealed.

Mechanical, thermal, morphological, and rheological characteristics of high performance 3D-printing lignin-based composites for additive manufacturing applications

DOE PAGES

Nguyen, Ngoc A.; Bowland, Christopher C.; Naskar, Amit K.

2018-05-29

Here, the article presents different mechanical, thermal and rheological data corresponding to the morphological formation within various renewable lignin-based composites containing acrylonitrile butadiene styrene (ABS), acrylonitrile butadiene rubber (NBR41, 41 mol% nitrile content), and carbon fibers (CFs). The data of 3D-printing properties and morphology of 3D-printed layers of selected lignin-based composites are revealed.

[The morphological characteristic of the skin lesions inflicted by plastic knives with four cutting edges].

PubMed

Leonov, S V; Finkel'shtein, V T

2015-01-01

The objective of the present work was to study the morphological features of the skin lesions inflicted by the blades of the Fgx Boot Blade I knives having four cutting edges. The study revealed the signs that can be used to distinguish between morphological characteristics of the stab and lacerated wounds having the primary and secondary incisions made by the four-edge blade.

The Morphological Diversity of DIG in Halos of Edge-on Spirals as Revealed by HST/ACS

NASA Astrophysics Data System (ADS)

Rossa, J.; Dahlem, M.; Dettmar, R.-J.; van der Marel, R. P.

2012-09-01

We present new results on extraplanar DIG (eDIG), based on high spatial resolution narrowband imaging observations of four late-type, actively star-forming edge-on spirals, obtained with ACS on-board HST. Our Hα observations reveal a multitude of structures on both small and large scales. Whereas all four galaxies have been studied with ground-based telescopes before, here the small scale structure of the extended emission line gas is presented for the very first time at a spatial resolution of 0.05'', corresponding to 5 pc at the mean distance to our galaxies. The eDIG morphology is very different for all four targets, as a result of their different star formation activity and galaxy mass. There is a very smooth DIG morphology observed in two of the galaxies (NGC 4634 and NGC 5775), whereas the other two (NGC 4700 and NGC 7090) show a much more complex morphology with intricate filaments, and bubbles and supershells. We find that the morphology of the eDIG, in particular the break-up of diffuse emission into filaments in galaxy halos, shows a strong dependence on the level of star formation activity per unit area, and eDIG can be arranged into a morphological sequence.

Growth of ultrananocrystalline diamond film by DC Arcjet plasma enhanced chemical vapor deposition

NASA Astrophysics Data System (ADS)

Chen, G. C.; Li, B.; Yan, Z. Q.; Liu, J.; Lu, F. X.; Ye, H.

2012-06-01

Self-standing diamond films were grown by DC Arcjet plasma enhanced chemical vapor deposition (CVD). The feed gasses were Ar/H2/CH4, in which the flow ratio of CH4 to H2 (F/F) was varied from 5% to 20%. Two distinct morphologies were observed by scanning electron microscope (SEM), i.e. the "pineapple-like" morphology and the "cauliflower-like" morphology. It was found that the morphologies of the as-grown films are strongly dependent on the flow ratio of CH4 to H2 in the feed gasses. High resolution transmission electron microscope (HRTEM) survey results revealed that there were nanocrystalline grains within the "pineapple-like" films whilst there were ultrananocrystalline grains within "cauliflower-like" films. X-ray diffraction (XRD) results suggested that (110) crystalline plane was the dominant surface in the "cauliflower-like" films whilst (100) crystalline plane was the dominant surface in the "pineapple-like" films. Raman spectroscopy revealed that nanostructured carbon features could be observed in both types of films. Plasma diagnosis was carried out in order to understand the morphology dependent growth mechanism. It could be concluded that the film morphology was strongly influenced by the density of gas phases. The gradient of C2 radical was found to be different along the growth direction under the different growth conditions.

Systematics of Cladophora spp. (Chlorophyta) from North Carolina, USA, based upon morphology and DNA sequence data with a description of Cladophora subtilissima sp. nov.

PubMed

Taylor, Robin L; Bailey, Jeffrey Craig; Freshwater, David Wilson

2017-06-01

Identification of Cladophora species is challenging due to conservation of gross morphology, few discrete autapomorphies, and environmental influences on morphology. Twelve species of marine Cladophora were reported from North Carolina waters. Cladophora specimens were collected from inshore and offshore marine waters for DNA sequence and morphological analyses. The nuclear-encoded rRNA internal transcribed spacer regions (ITS) were sequenced for 105 specimens and used in molecular assisted identification. The ITS1 and ITS2 region was highly variable, and sequences were sorted into ITS Sets of Alignable Sequences (SASs). Sequencing of short hyper-variable ITS1 sections from Cladophora type specimens was used to positively identify species represented by SASs when the types were made available. Secondary structures for the ITS1 locus were also predicted for each specimen and compared to predicted structures from Cladophora sequences available in GenBank. Nine ITS SASs were identified and representative specimens chosen for phylogenetic analyses of 18S and 28S rRNA gene sequences to reveal relationships with other Cladophora species. Phylogenetic analyses indicated that marine Cladophorales were polyphyletic and separated into two clades, the Cladophora clade and the "Siphonocladales" clade. Morphological analyses were performed to assess the consistency of character states within species, and complement the DNA sequence analyses. These analyses revealed intra- and interspecific character state variation, and that combined molecular and morphological analyses were required for the identification of species. One new report, Cladophora dotyana, and one new species Cladophora subtilissima sp. nov., were revealed, and increased the biodiversity of North Carolina marine Cladophora to 14 species. © 2017 Phycological Society of America.

Martian deltas: Morphology and distribution

NASA Technical Reports Server (NTRS)

Rice, J. W., Jr.; Scott, D. H.

1993-01-01

Recent detailed mapping has revealed numerous examples of Martian deltas. The location and morphology of these deltas are described. Factors that contribute to delta morphology are river regime, coastal processes, structural stability, and climate. The largest delta systems on Mars are located near the mouths of Maja, Maumee, Vedra, Ma'adim, Kasei, and Brazos Valles. There are also several smaller-scale deltas emplaced near channel mouths situated in Ismenius Lacus, Memnonia, and Arabia. Delta morphology was used to reconstruct type, quantity, and sediment load size transported by the debouching channel systems. Methods initially developed for terrestrial systems were used to gain information on the relationships between Martian delta morphology, river regime, and coastal processes.

Three-dimensional morphology of GaP-GaAs nanowires revealed by transmission electron microscopy tomography.

PubMed

Verheijen, Marcel A; Algra, Rienk E; Borgström, Magnus T; Immink, George; Sourty, Erwan; Enckevort, Willem J P van; Vlieg, Elias; Bakkers, Erik P A M

2007-10-01

We have investigated the morphology of heterostructured GaP-GaAs nanowires grown by metal-organic vapor-phase epitaxy as a function of growth temperature and V/III precursor ratio. The study of heterostructured nanowires with transmission electron microscopy tomography allowed the three-dimensional morphology to be resolved, and discrimination between the effect of axial (core) and radial (shell) growth on the morphology. A temperature- and precursor-dependent structure diagram for the GaP nanowire core morphology and the evolution of the different types of side facets during GaAs and GaP shell growth were constituted.

DNA Sequences from Formalin-Fixed Nematodes: Integrating Molecular and Morphological Approaches to Taxonomy

PubMed Central

Thomas, W. Kelley; Vida, J. T.; Frisse, Linda M.; Mundo, Manuel; Baldwin, James G.

1997-01-01

To effectively integrate DNA sequence analysis and classical nematode taxonomy, we must be able to obtain DNA sequences from formalin-fixed specimens. Microdissected sections of nematodes were removed from specimens fixed in formalin, using standard protocols and without destroying morphological features. The fixed sections provided sufficient template for multiple polymerase chain reaction-based DNA sequence analyses. PMID:19274156

Defining how aging Pseudotsuga and Abies compensate for multiple stresses through multi-criteria assessment of a functional-structural model

Treesearch

Maureen C. Kennedy; E. David Ford; Thomas M. Hinckley

2009-01-01

Many hypotheses have been advanced about factors that control tree longevity. We use a simulation model with multi-criteria optimization and Pareto optimality to determine branch morphologies in the Pinaceae that minimize the effect of growth limitations due to water stress while simultaneously maximizing carbohydrate gain. Two distinct branch morphologies in the...

Coastal Modeling System: Mathematical Formulations and Numerical Methods

DTIC Science & Technology

2014-03-01

sediment transport , and morphology change. The CMS was designed and developed for coastal inlets and navigation applications, including channel...numerical methods of hydrodynamic, salinity and sediment transport , and morphology change model CMS-Flow. The CMS- Flow uses the Finite Volume...and the influence of coastal structures. The implicit hydrodynamic model is coupled to a nonequilibrium transport model of multiple-sized total

A Quantile Regression Approach to Understanding the Relations among Morphological Awareness, Vocabulary, and Reading Comprehension in Adult Basic Education Students

ERIC Educational Resources Information Center

Tighe, Elizabeth L.; Schatschneider, Christopher

2016-01-01

The purpose of this study was to investigate the joint and unique contributions of morphological awareness and vocabulary knowledge at five reading comprehension levels in adult basic education (ABE) students. We introduce the statistical technique of multiple quantile regression, which enabled us to assess the predictive utility of morphological…

White light emission of monolithic InGaN/GaN grown on morphology-controlled, nanostructured GaN templates.

PubMed

Song, Keun Man; Kim, Do-Hyun; Kim, Jong-Min; Cho, Chu-Young; Choi, Jehyuk; Kim, Kahee; Park, Jinsup; Kim, Hogyoug

2017-06-02

We demonstrated an InGaN/GaN-based, monolithic, white light-emitting diode (LED) without phosphors by using morphology-controlled active layers formed on multi-facet GaN templates containing polar and semipolar surfaces. The nanostructured surface morphology was controlled by changing the growth time, and distinct multiple photoluminescence peaks were observed at 360, 460, and 560 nm; these features were caused by InGaN/GaN-based multiple quantum wells (MQWs) on the nanostructured facets. The origin of each multi-peak was related to the different indium (In) compositions in the different planes of the quantum wells grown on the nanostructured GaN. The emitting units of MQWs in the LED structures were continuously connected, which is different from other GaN-based nanorod or nanowire LEDs. Therefore, the suggested structure had a larger active area. From the electroluminescence spectrum of the fabricated LED, monolithic white light emission with CIE color coordinates of x = 0.306 and y = 0.333 was achieved via multi-facet control combined with morphology control of the metal organic chemical vapor deposition-selective area growth of InGaN/GaN MQWs.

White light emission of monolithic InGaN/GaN grown on morphology-controlled, nanostructured GaN templates

NASA Astrophysics Data System (ADS)

Song, Keun Man; Kim, Do-Hyun; Kim, Jong-Min; Cho, Chu-Young; Choi, Jehyuk; Kim, Kahee; Park, Jinsup; Kim, Hogyoug

2017-06-01

We demonstrated an InGaN/GaN-based, monolithic, white light-emitting diode (LED) without phosphors by using morphology-controlled active layers formed on multi-facet GaN templates containing polar and semipolar surfaces. The nanostructured surface morphology was controlled by changing the growth time, and distinct multiple photoluminescence peaks were observed at 360, 460, and 560 nm; these features were caused by InGaN/GaN-based multiple quantum wells (MQWs) on the nanostructured facets. The origin of each multi-peak was related to the different indium (In) compositions in the different planes of the quantum wells grown on the nanostructured GaN. The emitting units of MQWs in the LED structures were continuously connected, which is different from other GaN-based nanorod or nanowire LEDs. Therefore, the suggested structure had a larger active area. From the electroluminescence spectrum of the fabricated LED, monolithic white light emission with CIE color coordinates of x = 0.306 and y = 0.333 was achieved via multi-facet control combined with morphology control of the metal organic chemical vapor deposition-selective area growth of InGaN/GaN MQWs.

Increasing morphological complexity in multiple parallel lineages of the Crustacea

PubMed Central

Adamowicz, Sarah J.; Purvis, Andy; Wills, Matthew A.

2008-01-01

The prospect of finding macroevolutionary trends and rules in the history of life is tremendously appealing, but very few pervasive trends have been found. Here, we demonstrate a parallel increase in the morphological complexity of most of the deep lineages within a major clade. We focus on the Crustacea, measuring the morphological differentiation of limbs. First, we show a clear trend of increasing complexity among 66 free-living, ordinal-level taxa from the Phanerozoic fossil record. We next demonstrate that this trend is pervasive, occurring in 10 or 11 of 12 matched-pair comparisons (across five morphological diversity indices) between extinct Paleozoic and related Recent taxa. This clearly differentiates the pattern from the effects of lineage sorting. Furthermore, newly appearing taxa tend to have had more types of limbs and a higher degree of limb differentiation than the contemporaneous average, whereas those going extinct showed higher-than-average limb redundancy. Patterns of contemporary species diversity partially reflect the paleontological trend. These results provide a rare demonstration of a large-scale and probably driven trend occurring across multiple independent lineages and influencing both the form and number of species through deep time and in the present day. PMID:18347335

Extranodal posttransplant plasmacytic hyperplasia with subsequent posttransplant plasmacytic malignancy: six-year interval case report and review of the literature.

PubMed

Dunphy, Cherie H; Galambos, Csaba; Polski, Jacek M; Evans, H Lance; Gardner, Laura J; Grosso, Leonard E; Montone, Kathleen T

2002-03-01

Posttransplant lymphoproliferative disorders (PTLDs) represent a morphologic, immunophenotypic, and genotypic spectrum of disease. Most recently, Knowles et al divided PTLDs into 3 distinct categories: (1) plasmacytic hyperplasia, (2) polymorphic B-cell hyperplasia and polymorphic B-cell lymphoma, and (3) immunoblastic lymphoma and multiple myeloma. Although one form of PTLD may progress to another form, only 1 previous case has been reported in which multiple myeloma developed 14 months after an original diagnosis of plasmacytic hyperplasia. The type of solid organ transplant was not specified in that case. We report a post--cardiac transplant plasmacytic hyperplasia developing 7 years posttransplant. Six years subsequent to the plasmacytic hyperplasia, the patient developed a posttransplant plasmacytic malignancy, supported by morphology, flow cytometric immunophenotyping, and genotypic studies. Since we have no data to support disseminated bony disease or an abnormal serum protein, we have not used the term "multiple myeloma" for this case.

Morphological diversity of nitroguanidine crystals with enhanced mechanical performance and thermodynamic stability

NASA Astrophysics Data System (ADS)

Luo, Zhilong; Cui, Yingdan; Dong, Weibing; Xu, Qipeng; Zou, Gaoxing; Kang, Chao; Hou, Baohong; Chen, Song; Gong, Junbo

2017-12-01

Nitroguanidine (NQ) is a commonly used explosive, which has been widely used for both civilian and military explosive applications. However, the weak flowability and mechanical performance limit its application. In this work, mechanical performance and thermodynamic stability of NQ crystals were improved by controlling crystal morphologies in the crystallization process. Typical NQ crystals with multiple morphologies and single crystal form were obtained in the presence of additives during the cooling crystallization. The morphology controlled NQ crystals showed higher density, unimodal crystal size distribution and enhanced flowability. The additives showed the inhibitory effect on the nucleation of NQ crystals by in-situ FBRM and PVM determination, and the mechanism was analyzed by means of morphological prediction and molecular simulation. Furthermore, the morphology controlled NQ crystals suggested higher thermodynamic stability according to the calculation of entropy, enthalpy, Gibbs free energy and apparent activation energy on the basis of DSC results.

Electron tomography and cryo-SEM characterization reveals novel ultrastructural features of host-parasite interaction during Chlamydia abortus infection.

PubMed

Wilkat, M; Herdoiza, E; Forsbach-Birk, V; Walther, P; Essig, A

2014-08-01

Chlamydia (C.) abortus is a widely spread pathogen among ruminants that can be transmitted to women during pregnancy leading to severe systemic infection with consecutive abortion. As a member of the Chlamydiaceae, C. abortus shares the characteristic feature of an obligate intracellular biphasic developmental cycle with two morphological forms including elementary bodies (EBs) and reticulate bodies (RBs). In contrast to other chlamydial species, C. abortus ultrastructure has not been investigated yet. To do so, samples were fixed by high-pressure freezing and processed by different electron microscopic methods. Freeze-substituted samples were analysed by transmission electron microscopy, scanning transmission electron microscopical tomography and immuno-electron microscopy, and freeze-fractured samples were analysed by cryo-scanning electron microscopy. Here, we present three ultrastructural features of C. abortus that have not been reported up to now. Firstly, the morphological evidence that C. abortus is equipped with the type three secretion system. Secondly, the accumulation and even coating of whole inclusion bodies by membrane complexes consisting of multiple closely adjacent membranes which seems to be a C. abortus specific feature. Thirdly, the formation of small vesicles in the periplasmic space of RBs in the second half of the developmental cycle. Concerning the time point of their formation and the fact that they harbour chlamydial components, these vesicles might be morphological correlates of an intermediate step during the process of redifferentiation of RBs into EBs. As this feature has also been shown for C. trachomatis and C. pneumoniae, it might be a common characteristic of the family of Chlamydiaceae.

Unmasking the complexity of species identification in Australasian flying-foxes

PubMed Central

Danks, Melissa; Lott, Matthew J.; Dennison, Siobhan; Frankham, Greta J.; King, Andrew; Eldridge, Mark D. B.; Johnson, Rebecca N.; Divljan, Anja

2018-01-01

Pteropus (flying-foxes) are a speciose group of non-echolocating large bats, with five extant Australian species and 24 additional species distributed amongst the Pacific Islands. In 2015, an injured flying-fox with unusual facial markings was found in Sydney, Australia, following severe and widespread storms. Based on an initial assessment, the individual belonged to Pteropus but could not be readily identified to species. As a consequence, four hypotheses for its identification/origin were posited: the specimen represented (1) an undescribed Australian species; or (2) a morphological variant of a recognised Australian species; or (3) a hybrid individual; or (4) a vagrant from the nearby Southwest Pacific Islands. We used a combination of morphological and both mitochondrial- and nuclear DNA-based identification methods to assess these hypotheses. Based on the results, we propose that this morphologically unique Pteropus most likely represents an unusual P. alecto (black flying-fox) potentially resulting from introgression from another Pteropus species. Unexpectedly, this individual, and the addition of reference sequence data from newly vouchered specimens, revealed a previously unreported P. alecto mitochondrial DNA lineage. This lineage was distinct from currently available haplotypes. It also suggests long-term hybridisation commonly occurs between P. alecto and P. conspicillatus (spectacled flying-fox). This highlights the importance of extensive reference data, and the inclusion of multiple vouchered specimens for each species to encompass both intraspecific and interspecific variation to provide accurate and robust species identification. Moreover, our additional reference data further demonstrates the complexity of Pteropus species relationships, including hybridisation, and potential intraspecific biogeographical structure that may impact on their management and conservation. PMID:29634748

The Effects of Tissue-Nonspecific Alkaline Phosphatase Gene Therapy on Craniosynostosis and Craniofacial Morphology in the FGFR2C342Y/+ Mouse Model of Crouzon Craniosynostosis

PubMed Central

Wang, E; Nam, HK; Liu, J; Hatch, NE

2015-01-01

Objectives Craniosynostosis, the premature fusion of cranial bones, has traditionally been described as a disease of increased bone mineralization. However, multiple mouse models of craniosynostosis display craniosynostosis simultaneously with diminished cranial bone volume and/or density. We propose an alternative hypothesis that craniosynostosis results from abnormal tissue mineralization through the downregulation of tissue-nonspecific alkaline phosphatase (TNAP) enzyme downstream of activating mutations in FGFRs. Material & Methods Neonatal Crouzon (FGFRC342Y/+) and wild type (FGFR+/+) mice were injected with lentivirus to deliver a recombinant form of TNAP. Mice were sacrificed at four weeks post-natal. Serum was collected to test for alkaline phosphatase (AP), phosphorus, and calcium levels. Craniofacial bone fusion and morphology was assessed by micro-computed tomography. Results Injection with the TNAP lentivirus significantly increased serum AP levels (increased serum AP levels are indicative of efficient transduction and production of the recombinant protein), but results were variable and dependent upon viral lot and the litter of mice injected. Morphologic analysis revealed craniofacial form differences for inferior surface (p=.023) and cranial height (p=.014) regions between TNAP lentivirus injected and vehicle-injected Crouzon mice. With each unit increase in AP level, the odds of lambdoid suture fusion decreased by 84.2% and these results came close to statistical significance (p=.068). Conclusion These results suggest that TNAP deficiency may mediate FGFR2-associated craniosynostosis. Future studies should incorporate injection of recombinant TNAP protein, to avoid potential side effects and variable efficacy of lentiviral gene delivery. PMID:25865549

Hip morphology predicts posterior hip impingement in a cadaveric model.

PubMed

Morris, William Z; Fowers, Cody A; Weinberg, Douglas S; Millis, Michael B; Tu, Leigh-Anne; Liu, Raymond W

2018-05-01

Posterior hip impingement is a recently-identified cause of hip pain. The purpose of this study is to characterise posterior femoroacetabular and ischiofemoral impingement and identify its predisposing morphologic traits. Two hundred and six cadaveric hips were randomly selected and taken through controlled motion in two pure axes associated with posterior hip impingement: external rotation (through the mechanical axis) and adduction (coronal plane). The range of motion and location of impingement was noted for each specimen. Morphologic traits including femoral/acetabular version, and true neck-shaft angle (TNSA) were also measured. External rotation impingement occurred between the femoral neck and acetabulum in 83.0% of hips, and between the lesser trochanter and ischial tuberosity in 17.0%. Adduction impingement occurred between the lesser trochanter and ischial tuberosity in 78.6% of hips, and between the femoral neck and acetabulum in 21.4%. Multiple regression revealed that increased femoral/acetabular version predicted earlier external rotation and adduction impingement. Unstandardised betas ranging from -0.39 to -0.64 reflect that each degree of increased femoral/acetabular version individually accounts for a loss of external rotation or adduction of approximately half a degree before impingement ( p < 0.001 for each). Increased TNSA was associated with earlier adduction impingement only (unstandardised beta -0.35, p = 0.005). Relative femoral/acetabular anteversion was associated with earlier posterior hip impingement. Coxa valga was associated with earlier adduction impingement, but protective against external rotation impingement. These findings highlight the importance of monitoring correction during femoral/acetabular osteotomies, as overcorrection of retroversion may predispose to earlier posterior impingement.

Antarctic glossopterid diversity on a local scale: the presence of multiple megasporophyll genera, Upper Permian, Mt. Achernar, Transantarctic Mountains, Antarctica.

PubMed

Ryberg, Patricia E; Taylor, Edith L; Taylor, Thomas N

2012-09-01

The glossopterids are a group of plants that thrived during a time of global warming similar to what is happening on the Earth today as well as the transition from archaic plant groups to the ancestors of modern groups. The diversity of the glossopterid clade is based on the megasporangiate structures assigned to the group, because the vegetative and pollen-bearing structures vary little. The presence of numerous reproductive genera from a single Upper Permian locality in the central Transantarctic Mountains provides important data on local glossopterid diversity in Antarctica. Impression/compression fossils were imaged with a Leica 5000C digital camera on a dissecting microscope or a Fujifilm FinePix S1pro digital camera. Two megasporangiate taxa are described: Scutum leiophyllum, which represents the first confirmed record of the genus in Antarctica, and Lidgettoniopsis ramulus, a new morphology consisting of a pinnate structure with oppositely attached megasporophylls. Plumsteadia ovata specimens indicate that this genus can be larger than previously recorded and illustrate the vegetative surface with a distinct midrib. The presence of a laminar, multiovulate structure and a pinnate structure at the same site indicates that local-level glossopterid diversity in Antarctica is greater than previously hypothesized. The discovery of a new megasporophyll morphology in Antarctica (confirming the presence of three distinctive morphologies on the continent) shows that Antarctic glossopterid heterogeneity is on a par with other Gondwanan continents. The diversity of the Antarctic landscape reveals that high polar latitudes can sustain a diverse ecosystem during times of global warming.

A High Resolution Look at Black Sand Particles from Sand Dunes of Saudi Arabia Using Electron Microscopy

NASA Astrophysics Data System (ADS)

Hussain, M. M.; Aburizaiza, O. S.; Siddique, A.; Hershey, D. L.; Guerrieri, D. A.; Qurashi, J.; Abbass, M.; Blake, D. R.; Khwaja, H. A.

2013-12-01

Particulate air pollution is a problem of health concern. The microscopic make-up of different varieties of sand particles found and collected at a sand dune site in Badr, Saudi Arabia has been determined. Primary emphasis is given to the use of multiple high resolution electron microscopy (viz., Scanning Electron Microscopy with Energy Dispersive X-ray spectrometry (SEM/EDS) and Laser Scanning Microscopy (LSM)) to study the morphologies, emission source types, size, and elemental composition of the particles, and to evaluate the presence of ';coatings or contaminants' adsorbed or carried on by the black sand particles. White sand contains natural coarse particles associated with wind-blown releases from crustal surfaces, weathering of an igneous/metamorphic rock source, and volcanic activities. Silicates (alumino-silicates) and quartz (clear, milky, rose) dominate white sand and rest appears to contain calcite, olivine, feldspar, and magnetite. Black sand particles exhibit very different morphologies and microstructures (surface roughness) compared with white sand and volcanic ash. Morphological analyses have shown that the black sand contain ultrafine particles. Black sand is strongly magnetic, which indicates the mineral magnetite (strongly magnetic) or elemental iron. Iron, C, O, Ti, Si, V, and S particles dominate the black sand. Natural and anthropogenic sources have been implicated for the observed particles. Analysis revealed that the surface of white sand particles is mainly covered with the fine particles. It is known that emissions from combustion contain carbon soot and other contaminants that are easily absorbed by soil particles during a long-range transport.

Geomorphology of comet 67P/Churyumov–Gerasimenko

USGS Publications Warehouse

Birch, Samuel P. D.; Tang, Y.; Hayes, A. G.; Kirk, Randolph L.; Bodewitz, D.; Campins, H.; Fernandez, Y.; de Freitas Bart, R.; Kutsop, N. W.; Sierks, H.; Soderblom, J. M.; Squyres, S. W.; Vincent, J.-B.

2017-01-01

We present a global geomorphological map of comet 67P/Churyumov–Gerasimenko (67P/C-G) using data acquired by the Rosetta Orbiter’s OSIRIS Narrow Angle Camera. The images used in our study were acquired between 2014 August and 2015 May, before 67P/C-G passed through perihelion. Imagery of the Southern hemisphere was included in our study, allowing us to compare the contrasting hemispheres of 67P/C-G in a single study. Our work also puts into greater context the morphologies studied in previous works, and also the morphologies observed on previously visited cometary nuclei. Relative to other nuclei, 67P/C-G appears most similar to 81P/Wild 2, with a topographically heterogeneous surface dominated by smooth-floored pits. Our mapping describes the landscapes of 67P/C-G when they were first observed by Rosetta, and our map can be used to detect changes in surface morphologies after its perihelion passage. Our mapping reveals strong latitudinal dependences for emplaced units and a highly heterogeneous surface. Layered bedrock units that represent the exposed nucleus of 67P/C-G are dominant at southern latitudes, while topographically smooth, dust covered regions dominate the Northern hemisphere. Equatorial latitudes are dominated by smooth terrain units that show evidence for flow structures. We observe no obvious differences between the comet’s two lobes, with the only longitudinal variations being the Imhotep and Hatmehit basins. These correlations suggest a strong seasonal forcing on the surface evolution of 67P/C-G, where materials are transported from the Southern hemisphere to Northern hemisphere basins over multiple orbital time-scales.

Imaging the Effects of Prostaglandin Analogues on Cultured Trabecular Meshwork Cells by Coherent Anti-Stokes Raman Scattering

PubMed Central

Lei, Tim C.; Masihzadeh, Omid; Kahook, Malik Y.; Ammar, David A.

2013-01-01

Purpose. The aim of this study was to nondestructively monitor morphological changes to the lipid membranes of primary cultures of living human trabecular meshwork cells (hTMC) without the application of exogenous label. Methods. Live hTMC were imaged using two nonlinear optical techniques: coherent anti-Stokes Raman scattering (CARS) and two-photon autofluorescence (TPAF). The hTMC were treated with a commercial formulation of latanoprost (0.5 μg/mL) for 24 hours before imaging. Untreated cells and cells treated with vehicle containing the preservative benzalkonium chloride (BAK; 2 μg/mL) were imaged as controls. After CARS/TPAF imaging, hTMC were fixed, stained with the fluorescent lipid dye Nile Red, and imaged by conventional confocal microscopy to verify lipid membrane structures. Results. Analysis of CARS/TPAF images of hTMC treated with latanoprost revealed multiple intracellular lipid membranes absent from untreated or BAK-treated hTMC. Treatment of hTMC with sodium fluoride or ouabain, agents shown to cause morphological changes to hTMC, also did not induce formation of intracellular lipid membranes. Conclusions. CARS microscopy detected changes in living hTMC morphology that were validated by subsequent histological stain. Prostaglandin-induced changes to hTMC involved rearrangement of lipid membranes within these cells. These in vitro results identify a novel biological response to a class of antiglaucoma drugs, and further experiments are needed to establish how this effect is involved in the hypotensive action of prostaglandin analogues in vivo. PMID:23900606

Mammalian knock out cells reveal prominent roles for atlastin GTPases in ER network morphology.

PubMed

Zhao, Guohua; Zhu, Peng-Peng; Renvoisé, Benoît; Maldonado-Báez, Lymarie; Park, Seong Hee; Blackstone, Craig

2016-11-15

Atlastins are large, membrane-bound GTPases that participate in the fusion of endoplasmic reticulum (ER) tubules to generate the polygonal ER network in eukaryotes. They also regulate lipid droplet size and inhibit bone morphogenetic protein (BMP) signaling, though mechanisms remain unclear. Humans have three atlastins (ATL1, ATL2, and ATL3), and ATL1 and ATL3 are mutated in autosomal dominant hereditary spastic paraplegia and hereditary sensory neuropathies. Cellular investigations of atlastin orthologs in most yeast, plants, flies and worms are facilitated by the presence of a single or predominant isoform, but loss-of-function studies in mammalian cells are complicated by multiple, broadly-expressed paralogs. We have generated mouse NIH-3T3 cells lacking all three mammalian atlastins (Atl1/2/3) using CRISPR/Cas9-mediated gene knockout (KO). ER morphology is markedly disrupted in these triple KO cells, with prominent impairment in formation of three-way ER tubule junctions. This phenotype can be rescued by expression of distant orthologs from Saccharomyces cerevisiae (Sey1p) and Arabidopsis (ROOT HAIR DEFECTIVE3) as well as any one of the three human atlastins. Minimal, if any, changes are observed in the morphology of mitochondria and the Golgi apparatus. Alterations in BMP signaling and increased sensitivity to ER stress are also noted, though effects appear more modest. Finally, atlastins appear required for the proper differentiation of NIH-3T3 cells into an adipocyte-like phenotype. These findings have important implications for the pathogenesis of hereditary spastic paraplegias and sensory neuropathies associated with atlastin mutations. Published by Elsevier Inc.

High content analysis of phagocytic activity and cell morphology with PuntoMorph.

PubMed

Al-Ali, Hassan; Gao, Han; Dalby-Hansen, Camilla; Peters, Vanessa Ann; Shi, Yan; Brambilla, Roberta

2017-11-01

Phagocytosis is essential for maintenance of normal homeostasis and healthy tissue. As such, it is a therapeutic target for a wide range of clinical applications. The development of phenotypic screens targeting phagocytosis has lagged behind, however, due to the difficulties associated with image-based quantification of phagocytic activity. We present a robust algorithm and cell-based assay system for high content analysis of phagocytic activity. The method utilizes fluorescently labeled beads as a phagocytic substrate with defined physical properties. The algorithm employs statistical modeling to determine the mean fluorescence of individual beads within each image, and uses the information to conduct an accurate count of phagocytosed beads. In addition, the algorithm conducts detailed and sophisticated analysis of cellular morphology, making it a standalone tool for high content screening. We tested our assay system using microglial cultures. Our results recapitulated previous findings on the effects of microglial stimulation on cell morphology and phagocytic activity. Moreover, our cell-level analysis revealed that the two phenotypes associated with microglial activation, specifically cell body hypertrophy and increased phagocytic activity, are not highly correlated. This novel finding suggests the two phenotypes may be under the control of distinct signaling pathways. We demonstrate that our assay system outperforms preexisting methods for quantifying phagocytic activity in multiple dimensions including speed, accuracy, and resolution. We provide a framework to facilitate the development of high content assays suitable for drug screening. For convenience, we implemented our algorithm in a standalone software package, PuntoMorph. Copyright © 2017 Elsevier B.V. All rights reserved.

Interconnected network motifs control podocyte morphology and kidney function.

PubMed

Azeloglu, Evren U; Hardy, Simon V; Eungdamrong, Narat John; Chen, Yibang; Jayaraman, Gomathi; Chuang, Peter Y; Fang, Wei; Xiong, Huabao; Neves, Susana R; Jain, Mohit R; Li, Hong; Ma'ayan, Avi; Gordon, Ronald E; He, John Cijiang; Iyengar, Ravi

2014-02-04

Podocytes are kidney cells with specialized morphology that is required for glomerular filtration. Diseases, such as diabetes, or drug exposure that causes disruption of the podocyte foot process morphology results in kidney pathophysiology. Proteomic analysis of glomeruli isolated from rats with puromycin-induced kidney disease and control rats indicated that protein kinase A (PKA), which is activated by adenosine 3',5'-monophosphate (cAMP), is a key regulator of podocyte morphology and function. In podocytes, cAMP signaling activates cAMP response element-binding protein (CREB) to enhance expression of the gene encoding a differentiation marker, synaptopodin, a protein that associates with actin and promotes its bundling. We constructed and experimentally verified a β-adrenergic receptor-driven network with multiple feedback and feedforward motifs that controls CREB activity. To determine how the motifs interacted to regulate gene expression, we mapped multicompartment dynamical models, including information about protein subcellular localization, onto the network topology using Petri net formalisms. These computational analyses indicated that the juxtaposition of multiple feedback and feedforward motifs enabled the prolonged CREB activation necessary for synaptopodin expression and actin bundling. Drug-induced modulation of these motifs in diseased rats led to recovery of normal morphology and physiological function in vivo. Thus, analysis of regulatory motifs using network dynamics can provide insights into pathophysiology that enable predictions for drug intervention strategies to treat kidney disease.

Interconnected Network Motifs Control Podocyte Morphology and Kidney Function

PubMed Central

Azeloglu, Evren U.; Hardy, Simon V.; Eungdamrong, Narat John; Chen, Yibang; Jayaraman, Gomathi; Chuang, Peter Y.; Fang, Wei; Xiong, Huabao; Neves, Susana R.; Jain, Mohit R.; Li, Hong; Ma’ayan, Avi; Gordon, Ronald E.; He, John Cijiang; Iyengar, Ravi

2014-01-01

Podocytes are kidney cells with specialized morphology that is required for glomerular filtration. Diseases, such as diabetes, or drug exposure that causes disruption of the podocyte foot process morphology results in kidney pathophysiology. Proteomic analysis of glomeruli isolated from rats with puromycin-induced kidney disease and control rats indicated that protein kinase A (PKA), which is activated by adenosine 3′,5′-monophosphate (cAMP), is a key regulator of podocyte morphology and function. In podocytes, cAMP signaling activates cAMP response element–binding protein (CREB) to enhance expression of the gene encoding a differentiation marker, synaptopodin, a protein that associates with actin and promotes its bundling. We constructed and experimentally verified a β-adrenergic receptor–driven network with multiple feedback and feedforward motifs that controls CREB activity. To determine how the motifs interacted to regulate gene expression, we mapped multicompartment dynamical models, including information about protein subcellular localization, onto the network topology using Petri net formalisms. These computational analyses indicated that the juxtaposition of multiple feedback and feedforward motifs enabled the prolonged CREB activation necessary for synaptopodin expression and actin bundling. Drug-induced modulation of these motifs in diseased rats led to recovery of normal morphology and physiological function in vivo. Thus, analysis of regulatory motifs using network dynamics can provide insights into pathophysiology that enable predictions for drug intervention strategies to treat kidney disease. PMID:24497609

Self-assembly behaviours of peptide-drug conjugates: influence of multiple factors on aggregate morphology and potential self-assembly mechanism

NASA Astrophysics Data System (ADS)

Fan, Qin; Ji, Yujie; Wang, Jingjing; Wu, Li; Li, Weidong; Chen, Rui; Chen, Zhipeng

2018-04-01

Peptide-drug conjugates (PDCs) as self-assembly prodrugs have the unique and specific features to build one-component nanomedicines. Supramolecular structure based on PDCs could form various morphologies ranging from nanotube, nanofibre, nanobelt to hydrogel. However, the assembly process of PDCs is too complex to predict or control. Herein, we investigated the effects of extrinsic factors on assembly morphology and the possible formation of nanostructures based on PDCs. To this end, we designed a PDC consisting of hydrophobic drug (S)-ketoprofen (Ket) and valine-glutamic acid dimeric repeats peptide (L-VEVE) to study their assembly behaviour. Our results showed that the critical assembly concentration of Ket-L-VEVE was 0.32 mM in water to form various nanostructures which experienced from micelle, nanorod, nanofibre to nanoribbon. The morphology was influenced by multiple factors including molecular design, assembly time, pH and hydrogen bond inhibitor. On the basis of experimental results, we speculated the possible assembly mechanism of Ket-L-VEVE. The π-π stacking interaction between Ket molecules could serve as an anchor, and hydrogen bonded-induced β-sheets and hydrophilic/hydrophobic balance between L-VEVE peptide play structure-directing role in forming filament-like or nanoribbon morphology. This work provides a new sight to rationally design and precisely control the nanostructure of PDCs based on aromatic fragment.

Self-assembly behaviours of peptide-drug conjugates: influence of multiple factors on aggregate morphology and potential self-assembly mechanism.

PubMed

Fan, Qin; Ji, Yujie; Wang, Jingjing; Wu, Li; Li, Weidong; Chen, Rui; Chen, Zhipeng

2018-04-01

Peptide-drug conjugates (PDCs) as self-assembly prodrugs have the unique and specific features to build one-component nanomedicines. Supramolecular structure based on PDCs could form various morphologies ranging from nanotube, nanofibre, nanobelt to hydrogel. However, the assembly process of PDCs is too complex to predict or control. Herein, we investigated the effects of extrinsic factors on assembly morphology and the possible formation of nanostructures based on PDCs. To this end, we designed a PDC consisting of hydrophobic drug ( S )-ketoprofen (Ket) and valine-glutamic acid dimeric repeats peptide (L-VEVE) to study their assembly behaviour. Our results showed that the critical assembly concentration of Ket-L-VEVE was 0.32 mM in water to form various nanostructures which experienced from micelle, nanorod, nanofibre to nanoribbon. The morphology was influenced by multiple factors including molecular design, assembly time, pH and hydrogen bond inhibitor. On the basis of experimental results, we speculated the possible assembly mechanism of Ket-L-VEVE. The π-π stacking interaction between Ket molecules could serve as an anchor, and hydrogen bonded-induced β-sheets and hydrophilic/hydrophobic balance between L-VEVE peptide play structure-directing role in forming filament-like or nanoribbon morphology. This work provides a new sight to rationally design and precisely control the nanostructure of PDCs based on aromatic fragment.

Resolving phylogenetic incongruence to articulate homology and phenotypic evolution: a case study from Nematoda

PubMed Central

Ragsdale, Erik J.; Baldwin, James G.

2010-01-01

Modern morphology-based systematics, including questions of incongruence with molecular data, emphasizes analysis over similarity criteria to assess homology. Yet detailed examination of a few key characters, using new tools and processes such as computerized, three-dimensional ultrastructural reconstruction of cell complexes, can resolve apparent incongruence by re-examining primary homologies. In nematodes of Tylenchomorpha, a parasitic feeding phenotype is thus reconciled with immediate free-living outgroups. Closer inspection of morphology reveals phenotypes congruent with molecular-based phylogeny and points to a new locus of homology in mouthparts. In nematode models, the study of individually homologous cells reveals a conserved modality of evolution among dissimilar feeding apparati adapted to divergent lifestyles. Conservatism of cellular components, consistent with that of other body systems, allows meaningful comparative morphology in difficult groups of microscopic organisms. The advent of phylogenomics is synergistic with morphology in systematics, providing an honest test of homology in the evolution of phenotype. PMID:20106846

Blood platelet counts, morphology and morphometry in lions, Panthera leo.

PubMed

Du Plessis, L

2009-09-01

Due to logistical problems in obtaining sufficient blood samples from apparently healthy animals in the wild in order to establish normal haematological reference values, only limited information regarding the blood platelet count and morphology of free-living lions (Panthera leo) is available. This study provides information on platelet counts and describes their morphology with particular reference to size in two normal, healthy and free-ranging lion populations. Blood samples were collected from a total of 16 lions. Platelet counts, determined manually, ranged between 218 and 358 x 10(9)/l. Light microscopy showed mostly activated platelets of various sizes with prominent granules. At the ultrastructural level the platelets revealed typical mammalian platelet morphology. However, morphometric analysis revealed a significant difference (P < 0.001) in platelet size between the two groups of animals. Basic haematological information obtained in this study may be helpful in future comparative studies between animals of the same species as well as in other felids.

Hepatozoon silvestris sp. nov.: morphological and molecular characterization of a new species of Hepatozoon (Adeleorina: Hepatozoidae) from the European wild cat (Felis silvestris silvestris).

PubMed

Hodžić, Adnan; Alić, Amer; Prašović, Senad; Otranto, Domenico; Baneth, Gad; Duscher, Georg Gerhard

2017-04-01

Based on morphological and genetic characteristics, we describe a new species of Hepatozoon in the European wild cat (Felis silvestris silvestris), herein named Hepatozoon silvestris sp. nov. The study also provides the first data on the occurrence of H. felis in this wild felid. Hepatozoon meronts were observed in multiple cross-sections of different organs of four (44%) cats. Additionally, extracellular forms, resembling mature gamonts of Hepatozoon, were found in the spleen and myocardium of two cats. Furthermore, tissues of six animals (67%) were positive by PCR. Hepatozoon felis was identified infecting one cat (11%), whereas the 18S rRNA sequences of the remaining five cats (56%) were identical, but distinct from the sequences of H. felis. Phylogenetic analyses revealed that those sequences form a highly supported clade distant from other Hepatozoon spp. Future studies should include domestic cats from the areas where the wild cats positive for H. silvestris sp. nov. were found, in order to investigate their potential role to serve as intermediate hosts of this newly described species. Identification of its definitive host(s) and experimental transmission studies are required for elucidating the full life cycle of this parasite and the possible alternative routes of its transmission.

New information on the braincase of the North American therizinosaurian (Theropoda, Maniraptora) Falcarius utahensis

USGS Publications Warehouse

Smith, David; Zanno, Lindsay E.; Sanders, R. Kent; Deblieux, Donald D.; Kirkland, James I.

2011-01-01

Many disarticulated bones from multiple individuals of a primitive therizinosaurian, referred to Falcarius utahensis, were found in the paucispecific Crystal Geyser bonebed in the Lower Cretaceous Cedar Mountain Formation of eastern Utah. To date, more than 2000 specimens from this species have been excavated. Included in this collection are two partial braincases, one of which is designated the holotype. Here we describe the braincase morphology ofFalcarius utahensis. These specimens help establish the primitive cranial condition for the Therizinosauria and further substantiate intraspecific and contralateral braincase pneumatic variation in theropods. When combined with new observations on the cranial remains of the therizinosaurid Nothronychus mckinleyi derived from computed tomographic (CT) scans, the braincase morphology of Falcarius clarifies several evolutionary trends within the Therizinosauria and establishes a suite of synapomorphies for the Therizinosauridae. Trends within the clade include increased basicranial pneumatization (the development of a basisphenoid bulla and loss of external subcondylar recesses), anterior deflection of the supraoccipital, and the reduction of points of origin of the craniocervical musculature, associated with the loss of discrete basipterygoid processes, probably due to incorporation of these structures into the expanded hyperpneumatic bone. Finally, CT scans reveal a complete, nearly avian, inner ear with bird-like semicircular canals and a long cochlea indicating broad frequency discrimination.

Functional traits reveal the expansion and packing of ecological niche space underlying an elevational diversity gradient in passerine birds.

PubMed

Pigot, Alex L; Trisos, Christopher H; Tobias, Joseph A

2016-01-13

Variation in species richness across environmental gradients may be associated with an expanded volume or increased packing of ecological niche space. However, the relative importance of these alternative scenarios remains unknown, largely because standardized information on functional traits and their ecological relevance is lacking for major diversity gradients. Here, we combine data on morphological and ecological traits for 523 species of passerine birds distributed across an Andes-to-Amazon elevation gradient. We show that morphological traits capture substantial variation in species dietary (75%) and foraging niches (60%) when multiple independent trait dimensions are considered. Having established these relationships, we show that the 14-fold increase in species richness towards the lowlands is associated with both an increased volume and density of functional trait space. However, we find that increases in volume contribute little to changes in richness, with most (78%) lowland species occurring within the range of trait space occupied at high elevations. Taken together, our results suggest that high species richness is mainly associated with a denser occupation of functional trait space, implying an increased specialization or overlap of ecological niches, and supporting the view that niche packing is the dominant trend underlying gradients of increasing biodiversity towards the lowland tropics. © 2016 The Author(s).

Functional traits reveal the expansion and packing of ecological niche space underlying an elevational diversity gradient in passerine birds

PubMed Central

Pigot, Alex L.; Trisos, Christopher H.; Tobias, Joseph A.

2016-01-01

Variation in species richness across environmental gradients may be associated with an expanded volume or increased packing of ecological niche space. However, the relative importance of these alternative scenarios remains unknown, largely because standardized information on functional traits and their ecological relevance is lacking for major diversity gradients. Here, we combine data on morphological and ecological traits for 523 species of passerine birds distributed across an Andes-to-Amazon elevation gradient. We show that morphological traits capture substantial variation in species dietary (75%) and foraging niches (60%) when multiple independent trait dimensions are considered. Having established these relationships, we show that the 14-fold increase in species richness towards the lowlands is associated with both an increased volume and density of functional trait space. However, we find that increases in volume contribute little to changes in richness, with most (78%) lowland species occurring within the range of trait space occupied at high elevations. Taken together, our results suggest that high species richness is mainly associated with a denser occupation of functional trait space, implying an increased specialization or overlap of ecological niches, and supporting the view that niche packing is the dominant trend underlying gradients of increasing biodiversity towards the lowland tropics. PMID:26740616

What Explains Patterns of Diversification and Richness among Animal Phyla?

PubMed Central

Jezkova, Tereza; Wiens, John J.

2016-01-01

Animal phyla vary dramatically in species richness (from 1 species to >1.2 million), but the causes of this variation remain largely unknown. Animals have also evolved striking variation in morphology and ecology, including sessile marine taxa lacking heads, eyes, limbs, and complex organs (e.g. sponges), parasitic worms (e.g. nematodes, platyhelminths), and taxa with eyes, skeletons, limbs, and complex organs that dominate terrestrial ecosystems (arthropods, chordates). Relating this remarkable variation in traits to the diversification and richness of animal phyla is a fundamental yet unresolved problem in biology. Here, we test the impacts of 18 traits (including morphology, ecology, reproduction, and development) on diversification and richness of extant animal phyla. Using phylogenetic multiple regression, the best-fitting model includes five traits that explain ~74% of the variation in diversification rates (dioecy, parasitism, eyes/photoreceptors, a skeleton, non-marine habitat). However, a model including just three (skeleton, parasitism, habitat) explains nearly as much variation (~67%). Diversification rates then largely explain richness patterns. Our results also identify many striking traits that have surprisingly little impact on diversification (e.g. head, limbs, and complex circulatory and digestive systems). Overall, our results reveal the key factors that shape large-scale patterns of diversification and richness across >80% of all extant, described species. PMID:28221832

What Explains Patterns of Diversification and Richness among Animal Phyla?

PubMed

Jezkova, Tereza; Wiens, John J

2017-03-01

Animal phyla vary dramatically in species richness (from one species to >1.2 million), but the causes of this variation remain largely unknown. Animals have also evolved striking variation in morphology and ecology, including sessile marine taxa lacking heads, eyes, limbs, and complex organs (e.g., sponges), parasitic worms (e.g., nematodes, platyhelminths), and taxa with eyes, skeletons, limbs, and complex organs that dominate terrestrial ecosystems (arthropods, chordates). Relating this remarkable variation in traits to the diversification and richness of animal phyla is a fundamental yet unresolved problem in biology. Here, we test the impacts of 18 traits (including morphology, ecology, reproduction, and development) on diversification and richness of extant animal phyla. Using phylogenetic multiple regression, the best-fitting model includes five traits that explain ∼74% of the variation in diversification rates (dioecy, parasitism, eyes/photoreceptors, a skeleton, nonmarine habitat). However, a model including just three (skeleton, parasitism, habitat) explains nearly as much variation (∼67%). Diversification rates then largely explain richness patterns. Our results also identify many striking traits that have surprisingly little impact on diversification (e.g., head, limbs, and complex circulatory and digestive systems). Overall, our results reveal the key factors that shape large-scale patterns of diversification and richness across >80% of all extant, described species.

Nanostructure and force spectroscopy analysis of human peripheral blood CD4{sup +} T cells using atomic force microscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hu Mingqian; Wang Jiongkun; Cai Jiye

2008-09-12

To date, nanoscale imaging of the morphological changes and adhesion force of CD4{sup +} T cells during in vitro activation remains largely unreported. In this study, we used atomic force microscopy (AFM) to study the morphological changes and specific binding forces in resting and activated human peripheral blood CD4{sup +} T cells. The AFM images revealed that the volume of activated CD4{sup +} T cells increased and the ultrastructure of these cells also became complex. Using a functionalized AFM tip, the strength of the specific binding force of the CD4 antigen-antibody interaction was found to be approximately three times thatmore » of the unspecific force. The adhesion forces were not randomly distributed over the surface of a single activated CD4{sup +} T cell, indicated that the CD4 molecules concentrated into nanodomains. The magnitude of the adhesion force of the CD4 antigen-antibody interaction did not change markedly with the activation time. Multiple bonds involved in the CD4 antigen-antibody interaction were measured at different activation times. These results suggest that the adhesion force involved in the CD4 antigen-antibody interaction is highly selective and of high affinity.« less

Phylogeny of the "forgotten" cellular slime mold, Fonticula alba, reveals a key evolutionary branch within Opisthokonta.

PubMed

Brown, Matthew W; Spiegel, Frederick W; Silberman, Jeffrey D

2009-12-01

The shared ancestry between Fungi and animals has been unequivocally demonstrated by abundant molecular and morphological data for well over a decade. Along with the animals and Fungi, multiple protists have been placed in the supergroup Opisthokonta making it exceptionally diverse. In an effort to place the cellular slime mold Fonticula alba, an amoeboid protist with aggregative, multicellular fruiting, we sequenced five nuclear encoded genes; small subunit ribosomal RNA, actin, beta-tubulin, elongation factor 1-alpha, and the cytosolic isoform of heat shock protein 70 for phylogenetic analyses. Molecular trees demonstrate that Fonticula is an opisthokont that branches sister to filose amoebae in the genus Nuclearia. Fonticula plus Nuclearia are sister to Fungi. We propose a new name for this well-supported clade, Nucletmycea, incorporating Nuclearia, Fonticula, and Fungi. Fonticula represents the first example of a cellular slime mold morphology within Opisthokonta. Thus, there are four types of multicellularity in the supergroup-animal, fungal, colonial, and now aggregative. Our data indicate that multicellularity in Fonticula evolved independent of that found in the fungal and animal radiations. With the rapidly expanding sequence and genomic data becoming available from many opisthokont lineages, Fonticula may be fundamental to understanding opisthokont evolution as well as any possible commonalities involved with the evolution of multicellularity.

Fyn kinase genetic ablation causes structural abnormalities in mature retina and defective Müller cell function.

PubMed

Chavez-Solano, Marbella; Ibarra-Sanchez, Alfredo; Treviño, Mario; Gonzalez-Espinosa, Claudia; Lamas, Monica

2016-04-01

Fyn kinase is widely expressed in neuronal and glial cells of the brain, where it exerts multiple functional roles that affect fundamental physiological processes. The aim of our study was to investigate the, so far unknown, functional role of Fyn in the retina. We report that Fyn is expressed, in vivo, in a subpopulation of Müller glia. We used a mouse model of Fyn genetic ablation and Müller-enriched primary cultures to demonstrate that Fyn deficiency induces morphological alterations in the mature retina, a reduction in the thickness of the outer and inner nuclear layers and alterations in postnatal Müller cell physiology. These include shortening of Müller cell processes, a decrease in cell proliferation, inactivation of the Akt signal transduction pathway, a reduced number of focal adhesions points and decreased adhesion of these cells to the ECM. As abnormalities in Müller cell physiology have been previously associated to a compromised retinal function we evaluated behavioral responses to visual stimulation. Our results associate Fyn deficiency with impaired visual optokinetic responses under scotopic and photopic light conditions. Our study reveals novel roles for Fyn kinase in retinal morphology and Müller cell physiology and suggests that Fyn is required for optimal visual processing. Copyright © 2016 Elsevier Inc. All rights reserved.

Statistical characterization of surface features from tungsten-coated divertor inserts in the DIII-D Metal Rings Campaign

NASA Astrophysics Data System (ADS)

Adams, Jacob; Unterberg, Ezekial; Chrobak, Christopher; Stahl, Brian; Abrams, Tyler

2017-10-01

Continuing analysis of tungsten-coated inserts from the recent DIII-D Metal Rings Campaign utilizes a statistical approach to study carbon migration and deposition on W surfaces and to characterize the pre- versus post-exposure surface morphology. A TZM base was coated with W using both CVD and PVD and allowed for comparison between the two coating methods. The W inserts were positioned in the lower DIII-D divertor in both the upper (shelf) region and lower (floor) region and subjected to multiple plasma shots, primarily in H-mode. Currently, the post-exposure W inserts are being characterized using SEM/EDX to qualify the surface morphology and to quantify the surface chemical composition. In addition, profilometry is being used to measure the surface roughness of the inserts both before and after plasma exposure. Preliminary results suggest a correlation between the pre-exposure surface roughness and the level of carbon deposited on the surface. Furthermore, ongoing in-depth analysis may reveal insights into the formation mechanism of nanoscale bumps found in the carbon-rich regions of the W surfaces that have not yet been explained. Work supported in part by US DoE under the Science Undergraduate Laboratory Internship (SULI) program and under DE-FC02-04ER54698.

New Ceratocystis species from Eucalyptus and Cunninghamia in South China.

PubMed

Liu, FeiFei; Mbenoun, Michael; Barnes, Irene; Roux, Jolanda; Wingfield, Michael J; Li, GuoQing; Li, JieQiong; Chen, ShuaiFei

2015-06-01

During routine surveys for possible fungal pathogens in the rapidly expanding plantations of Eucalyptus and Cunninghamia lanceolata in China, numerous isolates of unknown species in the genus Ceratocystis (Microascales) were obtained from tree wounds. In this study we identified the Ceratocystis isolates from Eucalyptus and Cunninghamia in the GuangDong, GuangXi, FuJian and HaiNan Provinces of South China based on morphology and through comparisons of DNA sequence data for the ITS, partial β-tubulin and TEF-1α gene regions. Morphological and DNA sequence comparisons revealed two previously unknown species residing in the Indo-Pacific Clade. These are described here as Ceratocystis cercfabiensis sp. nov. and Ceratocystis collisensis sp. nov. Isolates of Ceratocystis cercfabiensis showed intragenomic variation in their ITS sequences and four strains were selected for cloning of the ITS gene region. Twelve ITS haplotypes were obtained from 17 clones selected for sequencing, differing in up to seven base positions and representing two separate phylogenetic groups. This is the first evidence of multiple ITS types in isolates of Ceratocystis residing in the Indo-Pacific Clade. Caution should thus be exercised when using the ITS gene region as a barcoding marker for Ceratocystis species in this clade. This study also represents the first record of a species of Ceratocystis from Cunninghamia.

Correlation between morphology, electron band structure, and resistivity of Pb atomic chains on the Si(5 5 3)-Au surface

NASA Astrophysics Data System (ADS)

Jałochowski, M.; Kwapiński, T.; Łukasik, P.; Nita, P.; Kopciuszyński, M.

2016-07-01

Structural and electron transport properties of multiple Pb atomic chains fabricated on the Si(5 5 3)-Au surface are investigated using scanning tunneling spectroscopy, reflection high electron energy diffraction, angular resolved photoemission electron spectroscopy and in situ electrical resistance. The study shows that Pb atomic chains growth modulates the electron band structure of pristine Si(5 5 3)-Au surface and hence changes its sheet resistivity. Strong correlation between chains morphology, electron band structure and electron transport properties is found. To explain experimental findings a theoretical tight-binding model of multiple atomic chains interacting on effective substrate is proposed.

High level of cryptic species diversity revealed by sympatric lineages of Southeast Asian forest frogs

PubMed Central

Stuart, Bryan L; Inger, Robert F; Voris, Harold K

2006-01-01

Amphibians tend to exhibit conservative morphological evolution, and the application of molecular and bioacoustic tools in systematic studies have been effective at revealing morphologically ‘cryptic’ species within taxa that were previously considered to be a single species. We report molecular genetic findings on two forest-dwelling ranid frogs from localities across Southeast Asia, and show that sympatric evolutionary lineages of morphologically cryptic frogs are a common pattern. These findings imply that species diversity of Southeast Asian frogs remains significantly underestimated, and taken in concert with other molecular investigations, suggest there may not be any geographically widespread, forest-dwelling frog species in the region. Accurate assessments of diversity and distributions are needed to mitigate extinctions of evolutionary lineages in these threatened vertebrates. PMID:17148433

In vitro design of a novel lytic bacteriophage cocktail with therapeutic potential against organisms causing diabetic foot infections.

PubMed

Mendes, João J; Leandro, Clara; Mottola, Carla; Barbosa, Raquel; Silva, Filipa A; Oliveira, Manuela; Vilela, Cristina L; Melo-Cristino, José; Górski, Andrzej; Pimentel, Madalena; São-José, Carlos; Cavaco-Silva, Patrícia; Garcia, Miguel

2014-08-01

In patients with diabetes mellitus, foot infections pose a significant risk. These are complex infections commonly caused by Staphylococcus aureus, Pseudomonas aeruginosa and Acinetobacter baumannii, all of which are potentially susceptible to bacteriophages. Here, we characterized five bacteriophages that we had determined previously to have antimicrobial and wound-healing potential in chronic S. aureus, P. aeruginosa and A. baumannii infections. Morphological and genetic features indicated that the bacteriophages were lytic members of the family Myoviridae or Podoviridae and did not harbour any known bacterial virulence genes. Combinations of the bacteriophages had broad host ranges for the different target bacterial species. The activity of the bacteriophages against planktonic cells revealed effective, early killing at 4 h, followed by bacterial regrowth to pre-treatment levels by 24 h. Using metabolic activity as a measure of cell viability within established biofilms, we found significant cell impairment following bacteriophage exposure. Repeated treatment every 4 h caused a further decrease in cell activity. The greatest effects on both planktonic and biofilm cells occurred at a bacteriophage : bacterium input multiplicity of 10. These studies on both planktonic cells and established biofilms allowed us to better evaluate the effects of a high input multiplicity and a multiple-dose treatment protocol, and the findings support further clinical development of bacteriophage therapy. © 2014 The Authors.

Gone with the trees: Phylogeography of Rhodiola sect. Trifida (Crassulaceae) reveals multiple refugia on the Qinghai-Tibetan Plateau.

PubMed

Li, Yuan-Cong; Zhong, Da-Lv; Rao, Guang-Yuan; Wen, Jun; Ren, Yi; Zhang, Jian-Qiang

2018-04-01

Quaternary climatic oscillations have had tremendous effects on current distribution of species. Previous studies unraveled multiple microrefugia on the Qinghai-Tibetan Plateau (QTP) in two woody plants. Still we know little whether herbs growing in forests responded to climatic oscillations similarly. We herein conducted a phylogeographic study on Rhodiola sect. Trifida, an herbaceous group endemic to the QTP, which mainly growing on the forest floors, using plastid and ITS sequences as well as ecological niche modeling. The origin and divergence of major clades of sect. Trifida were in accordance with the last phase of the QTP uplifts. Mismatch distribution analysis indicated a range expansion dated to ca. 135 thousand years ago. A high frequency and an even distribution of private haplotypes in both plastid and ITS data sets throughout the distribution of sect. Trifida were detected. The ecological niche modeling results showed that there were suitable habitats on the QTP platform during the LGM. Our results found that multiple microrefugia existed on the QTP platform, supporting the hypothesis that species with similar geographic distribution and inhabiting the same community had similar responses to the Quaternary climatic oscillations. Furthermore, species delimitations in sect. Trifida need to be tested based on integrative evidence from morphological, ecological and genetic data. Copyright © 2018 Elsevier Inc. All rights reserved.

Phosphoproteome analysis reveals a critical role for hedgehog signalling in osteoblast morphological transitions.

PubMed

Marumoto, Ariane; Milani, Renato; da Silva, Rodrigo A; da Costa Fernandes, Célio Junior; Granjeiro, José Mauro; Ferreira, Carmen V; Peppelenbosch, Maikel P; Zambuzzi, Willian F

2017-10-01

The reciprocal and adaptive interactions between cells and substrates governing morphological transitions in the osteoblast compartment remain largely obscure. Here we show that osteoblast cultured in basement membrane matrix (Matrigel™) exhibits significant morphological changes after ten days of culture, and we decided to exploit this situation to investigate the molecular mechanisms responsible for guiding osteoblast morphological transitions. As almost all aspects of cellular physiology are under control of kinases, we generated more or less comprehensive cellular kinome profiles employing PepChip peptide arrays that contain over 1000 consensus substrates of kinase peptide. The results obtained were used to construct interactomes, and these revealed an important role for FoxO in mediating morphological changes of osteoblast, which was validated by Western blot technology when FoxO was significantly up-expressed in response to Matrigel™. As FoxO is a critical protein in canonical hedgehog signalling, we decided to explore the possible involvement of hedgehog signalling during osteoblast morphological changes. It appeared that osteoblast culture in Matrigel™ stimulates release of a substantial amounts Shh while concomitantly inducing upregulation of the expression of the bona fide hedgehog target genes Gli-1 and Patched. Functional confirmation of the relevance of these results for osteoblast morphological transitions came from experiments in which Shh hedgehog signalling was inhibited using the well-established pathway inhibitor cyclopamine (Cyc). In the presence of Cyc, culture of osteoblasts in Matrigel™ is not capable of inducing morphological changes but appears to provoke a proliferative response as evident from the upregulation of Cyclin D3 and cdk4. The most straightforward interpretation of our results is that hedgehog signalling is both necessary and sufficient for membrane matrix-based morphological transitions. Copyright © 2017 Elsevier Inc. All rights reserved.

Morphological and Compositional (S)TEM Analysis of Multiple Exciton Generation Solar Cells

NASA Astrophysics Data System (ADS)

Wisnivesky-Rocca-Rivarola, F.; Davis, N. J. L. K.; Bohm, M.; Ducati, C.

2015-10-01

Quantum confinement of charge carriers in semiconductor nanocrystals produces optical and electronic properties that have the potential to enhance the power conversion efficiency of solar cells. One of these properties is the efficient formation of more than one electron-hole pair from a single absorbed photon, in a process called multiple exciton generation (MEG). In this work we studied the morphology of nanocrystal multilayers of PbSe treated with CdCl2 using complementary imaging and spectroscopy techniques to characterise the chemical composition and morphology of full MEG devices made with PbSe nanorods (NRs). IN the scanning TEM (STEM), plan view images and chemical maps were obtained of the nanocrystal layers, which allowed for the analysis of crystal structure and orientation, as well as size distribution and aspect ratio. These results were complemented by cross-sectional images of full devices, which allowed accessing the structure of each layer that composes the device, including the nanorod packing in the active nanocrystal layer.

Aggregation and morphology control enables multiple cases of high-efficiency polymer solar cells

PubMed Central

Liu, Yuhang; Zhao, Jingbo; Li, Zhengke; Mu, Cheng; Hu, Huawei; Jiang, Kui; Lin, Haoran; Ade, Harald; Yan, He

2014-01-01

Although the field of polymer solar cell has seen much progress in device performance in the past few years, several limitations are holding back its further development. For instance, current high-efficiency (>9.0%) cells are restricted to material combinations that are based on limited donor polymers and only one specific fullerene acceptor. Here we report the achievement of high-performance (efficiencies up to 10.8%, fill factors up to 77%) thick-film polymer solar cells for multiple polymer:fullerene combinations via the formation of a near-ideal polymer:fullerene morphology that contains highly crystalline yet reasonably small polymer domains. This morphology is controlled by the temperature-dependent aggregation behaviour of the donor polymers and is insensitive to the choice of fullerenes. The uncovered aggregation and design rules yield three high-efficiency (>10%) donor polymers and will allow further synthetic advances and matching of both the polymer and fullerene materials, potentially leading to significantly improved performance and increased design flexibility. PMID:25382026

A novel multilocus phylogenetic estimation reveals unrecognized diversity in Asian horned toads, genus Megophrys sensu lato (Anura: Megophryidae).

PubMed

Chen, Jin-Min; Zhou, Wei-Wei; Poyarkov, Nikolay A; Stuart, Bryan L; Brown, Rafe M; Lathrop, Amy; Wang, Ying-Yong; Yuan, Zhi-Yong; Jiang, Ke; Hou, Mian; Chen, Hong-Man; Suwannapoom, Chatmongkon; Nguyen, Sang Ngoc; Duong, Tang Van; Papenfuss, Theodore J; Murphy, Robert W; Zhang, Ya-Ping; Che, Jing

2017-01-01

The horned toad assemblage, genus Megophrys sensu lato, currently includes three groups previously recognized as the genera Atympanophrys, Xenophrys and Megophrys sensu stricto. The taxonomic status and species composition of the three groups remain controversial due to conflicting phenotypic analyses and insufficient phylogenetic reconstruction; likewise, the position of the monotypic Borneophrys remains uncertain with respect to the horned toads. Further, the diversity of the horned toads remains poorly understood, especially for widespread species. Herein, we evaluate species-level diversity based on 45 of the 57 described species from throughout southern China, Southeast Asia and the Himalayas using Bayesian inference trees and the Generalized Mixed Yule Coalescent (GMYC) approach. We estimate the phylogeny using both mitochondrial and nuclear DNA data. Analyses reveal statistically significant mito-nuclear discordance. All analyses resolve paraphyly for horned toads involving multiple strongly supported clades. These clades correspond with geography. We resurrect the genera Atympanophrys and Xenophrys from the synonymy of Megophrys to eliminate paraphyly of Megophrys s.l. and to account for the morphological, molecular and biogeographic differences among these groups, but we also provide an alternative option. Our study suggests that Borneophrys is junior synonym of Megophrys sensu stricto. We provide an estimation of timeframe for the horned toads. The mitochondrial and nuclear trees indicate the presence of many putative undescribed species. Widespread species, such as Xenophrys major and X. minor, likely have dramatically underestimated diversity. The integration of morphological and molecular evidence can validate this discovery. Montane forest dynamics appear to play a significant role in driving diversification of horned toads. Copyright © 2016 Elsevier Inc. All rights reserved.

Climatic drivers of leaf traits and genetic divergence in the tree Annona crassiflora: a broad spatial survey in the Brazilian savannas.

PubMed

Ribeiro, Priciane C; Souza, Matheus L; Muller, Larissa A C; Ellis, Vincenzo A; Heuertz, Myriam; Lemos-Filho, José P; Lovato, Maria Bernadete

2016-11-01

The Cerrado is the largest South American savanna and encompasses substantial species diversity and environmental variation. Nevertheless, little is known regarding the influence of the environment on population divergence of Cerrado species. Here, we searched for climatic drivers of genetic (nuclear microsatellites) and leaf trait divergence in Annona crassiflora, a widespread tree in the Cerrado. The sampling encompassed all phytogeographic provinces of the continuous area of the Cerrado and included 397 individuals belonging to 21 populations. Populations showed substantial genetic and leaf trait divergence across the species' range. Our data revealed three spatially defined genetic groups (eastern, western and southern) and two morphologically distinct groups (eastern and western only). The east-west split in both the morphological and genetic data closely mirrors previously described phylogeographic patterns of Cerrado species. Generalized linear mixed effects models and multiple regression analyses revealed several climatic factors associated with both genetic and leaf trait divergence among populations of A. crassiflora. Isolation by environment (IBE) was mainly due to temperature seasonality and precipitation of the warmest quarter. Populations that experienced lower precipitation summers and hotter winters had heavier leaves and lower specific leaf area. The southwestern area of the Cerrado had the highest genetic diversity of A. crassiflora, suggesting that this region may have been climatically stable. Overall, we demonstrate that a combination of current climate and past climatic changes have shaped the population divergence and spatial structure of A. crassiflora. However, the genetic structure of A. crassiflora reflects the biogeographic history of the species more strongly than leaf traits, which are more related to current climate. © 2016 John Wiley & Sons Ltd.

Effective killing of the human pathogen Candida albicans by a specific inhibitor of non-essential mitotic kinesin Kip1p

PubMed Central

Chua, Penelope R; Roof, David M; Lee, Yan; Sakowicz, Roman; Clarke, David; Pierce, Dan; Stephens, Thoryn; Hamilton, Matthew; Morgan, Brad; Morgans, David; Nakai, Takashi; Tomasi, Adam; Maxon, Mary E

2007-01-01

Kinesins from the bipolar (Kinesin-5) family are conserved in eukaryotic organisms and play critical roles during the earliest stages of mitosis to mediate spindle pole body separation and formation of a bipolar mitotic spindle. To date, genes encoding bipolar kinesins have been reported to be essential in all organisms studied. We report the characterization of CaKip1p, the sole member of this family in the human pathogenic yeast Candida albicans. C. albicans Kip1p appears to localize to the mitotic spindle and loss of CaKip1p function interferes with normal progression through mitosis. Inducible excision of CaKIP1 revealed phenotypes unique to C. albicans, including viable homozygous Cakip1 mutants and an aberrant spindle morphology in which multiple spindle poles accumulate in close proximity to each other. Expression of the C. albicans Kip1 motor domain in Escherichia coli produced a protein with microtubule-stimulated ATPase activity that was inhibited by an aminobenzothiazole (ABT) compound in an ATP-competitive fashion. This inhibition results in ‘rigor-like’, tight association with microtubules in vitro. Upon treatment of C. albicans cells with the ABT compound, cells were killed, and terminal phenotype analysis revealed an aberrant spindle morphology similar to that induced by loss of the CaKIP1 gene. The ABT compound discovered is the first example of a fungal spindle inhibitor targeted to a mitotic kinesin. Our results also show that the non-essential nature and implementation of the bipolar motor in C. albicans differs from that seen in other organisms, and suggest that inhibitors of a non-essential mitotic kinesin may offer promise as cidal agents for antifungal drug discovery. PMID:17573815

Quantitative Analysis of Complex Glioma Cell Migration on Electrospun Polycaprolactone Using Time-Lapse Microscopy

PubMed Central

Johnson, Jed; Nowicki, M. Oskar; Lee, Carol H.; Chiocca, E. Antonio; Viapiano, Mariano S.; Lawler, Sean E.

2009-01-01

Malignant gliomas are the most common tumors originating within the central nervous system and account for over 15,000 deaths annually in the United States. The median survival for glioblastoma, the most common and aggressive of these tumors, is only 14 months. Therapeutic strategies targeting glioma cells migrating away from the tumor core are currently hampered by the difficulty of reproducing migration in the neural parenchyma in vitro. We utilized a tissue engineering approach to develop a physiologically relevant model of glioma cell migration. This revealed that glioma cells display dramatic differences in migration when challenged by random versus aligned electrospun poly-ɛ-caprolactone nanofibers. Cells on aligned fibers migrated at an effective velocity of 4.2 ± 0.39 μm/h compared to 0.8 ± 0.08 μm/h on random fibers, closely matching in vivo models and prior observations of glioma spread in white versus gray matter. Cells on random fibers exhibited extension along multiple fiber axes that prevented net motion; aligned fibers promoted a fusiform morphology better suited to infiltration. Time-lapse microscopy revealed that the motion of individual cells was complex and was influenced by cell cycle and local topography. Glioma stem cell–containing neurospheres seeded on random fibers did not show cell detachment and retained their original shape; on aligned fibers, cells detached and migrated in the fiber direction over a distance sixfold greater than the perpendicular direction. This chemically and physically flexible model allows time-lapse analysis of glioma cell migration while recapitulating in vivo cell morphology, potentially allowing identification of physiological mediators and pharmacological inhibitors of invasion. PMID:19199562

Multiple stressor effects on biological quality elements in the Ebro River: Present diagnosis and predicted responses.

PubMed

Herrero, Albert; Gutiérrez-Cánovas, Cayetano; Vigiak, Olga; Lutz, Stefanie; Kumar, Rohini; Gampe, David; Huber-García, Verena; Ludwig, Ralf; Batalla, Ramon; Sabater, Sergi

2018-07-15

Multiple abiotic stressors affect the ecological status of water bodies. The status of waterbodies in the Ebro catchment (NE Spain) is evaluated using the biological quality elements (BQEs) of diatoms, invertebrates and macrophytes. The multi-stressor influence on the three BQEs was evaluated using the monitoring dataset available from the catchment water authority. Nutrient concentrations, especially total phosphorus (TP), affected most of the analyzed BQEs, while changes in mean discharge, water temperature, or river morphology did not show significant influences. Linear statistical models were used to evaluate the change of water bodies' ecological status under different combinations of future socioeconomic and climate scenarios. Changes in land use, rainfall, water temperature, mean discharge, TP and nitrate concentrations were modeled according to the future scenarios. These revealed an evolution of the abiotic stressors that could lead to a general decrease in the ecosystem quality of water bodies within the Ebro catchment. This deterioration was especially evidenced on the diatoms and invertebrate biological indices, mainly because of the foreseen increase in TP concentrations. Water bodies located in the headwaters were seen as the most sensitive to future changes. Copyright © 2018 The Author(s). Published by Elsevier B.V. All rights reserved.

Miocene honey bees from the Randeck Maar of southwestern Germany (Hymenoptera, Apidae)

PubMed Central

Kotthoff, Ulrich; Wappler, Torsten; Engel, Michael S.

2011-01-01

Abstract The Miocene Randeck Maar (southwestern Germany) is one of the only sites with abundant material of fossil honey bees. The fauna has been the focus of much scrutiny by early authors who recognized multiple species or subspecies within the fauna. The history of work on the Randeck Maar is briefly reviewed and these fossils placed into context with other Tertiary and living species of the genus Apis Linnaeus (Apinae: Apini). Previously unrecorded specimens from Randeck Maar were compared with earlier series in an attempt to evaluate the observed variation. A morphometric analysis of forewing venation angles across representative Recent and Tertiary species of Apis as well as various non-Apini controls was undertaken to evaluate the distribution of variation in fossil honey bees. The resulting dendrogram shows considerable variation concerning the wing venation of Miocene Apini, but intergradation of other morphological characters reveals no clear pattern of separate species. This suggests that a single, highly variable species was present in Europe during the Miocene. The pattern also supports the notion that the multiple species and subspecies proposed by earlier authors for the Randeck Maar honey bee fauna are not valid, and all are accordingly recognized as Apis armbrusteri Zeuner. PMID:21594072

Evolution of morphology and locomotor performance in anurans: relationships with microhabitat diversification.

PubMed

Citadini, J M; Brandt, R; Williams, C R; Gomes, F R

2018-03-01

The relationships between morphology, performance, behavior and ecology provide evidence for multiple and complex phenotypic adaptations. The anuran body plan, for example, is evolutionarily conserved and shows clear specializations to jumping performance back at least to the early Jurassic. However, there are instances of more recent adaptation to habit diversity in the post-cranial skeleton, including relative limb length. The present study tested adaptive models of morphological evolution in anurans associated with the diversity of microhabitat use (semi-aquatic arboreal, fossorial, torrent, and terrestrial) in species of anuran amphibians from Brazil and Australia. We use phylogenetic comparative methods to determine which evolutionary models, including Brownian motion (BM) and Ornstein-Uhlenbeck (OU) are consistent with morphological variation observed across anuran species. Furthermore, this study investigated the relationship of maximum distance jumped as a function of components of morphological variables and microhabitat use. We found there are multiple optima of limb lengths associated to different microhabitats with a trend of increasing hindlimbs in torrent, arboreal, semi-aquatic whereas fossorial and terrestrial species evolve toward optima with shorter hindlimbs. Moreover, arboreal, semi-aquatic and torrent anurans have higher jumping performance and longer hindlimbs, when compared to terrestrial and fossorial species. We corroborate the hypothesis that evolutionary modifications of overall limb morphology have been important in the diversification of locomotor performance along the anuran phylogeny. Such evolutionary changes converged in different phylogenetic groups adapted to similar microhabitat use in two different zoogeographical regions. © 2018 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2018 European Society For Evolutionary Biology.

Utility of light scatter in the morphological analysis of sperm

EPA Science Inventory

We were able to differentiate the morphologically diverse sperm nuclei of four animal species by using an Ortho flow cytometer to detect the forward light scatter from a red (helium-neon) laser. Cytograms depicting the axial light loss and forward red scatter signals revealed uni...

Study of three interesting Amanita species from Thailand: Morphology, multiple-gene phylogeny and toxin analysis

PubMed Central

Thongbai, Benjarong; Miller, Steven L.; Stadler, Marc; Wittstein, Kathrin; Hyde, Kevin D.; Lumyong, Saisamorn

2017-01-01

Amanita ballerina and A. brunneitoxicaria spp. nov. are introduced from Thailand. Amanita fuligineoides is also reported for the first time from Thailand, increasing the known distribution of this taxon. Together, those findings support our view that many taxa are yet to be discovered in the region. While both morphological characters and a multiple-gene phylogeny clearly place A. brunneitoxicaria and A. fuligineoides in sect. Phalloideae (Fr.) Quél., the placement of A. ballerina is problematic. On the one hand, the morphology of A. ballerina shows clear affinities with stirps Limbatula of sect. Lepidella. On the other hand, in a multiple-gene phylogeny including taxa of all sections in subg. Lepidella, A. ballerina and two other species, including A. zangii, form a well-supported clade sister to the Phalloideae sensu Bas 1969, which include the lethal “death caps” and “destroying angels”. Together, the A. ballerina-A. zangii clade and the Phalloideae sensu Bas 1969 also form a well-supported clade. We therefore screened for two of the most notorious toxins by HPLC-MS analysis of methanolic extracts from the basidiomata. Interestingly, neither α-amanitin nor phalloidin was found in A. ballerina, whereas Amanita fuligineoides was confirmed to contain both α-amanitin and phalloidin, and A. brunneitoxicaria contained only α-amanitin. Together with unique morphological characteristics, the position in the phylogeny indicates that A. ballerina is either an important link in the evolution of the deadly Amanita sect. Phalloideae species, or a member of a new section also including A. zangii. PMID:28767681

Traits, properties, and performance: how woody plants combine hydraulic and mechanical functions in a cell, tissue, or whole plant.

PubMed

Lachenbruch, Barbara; McCulloh, Katherine A

2014-12-01

This review presents a framework for evaluating how cells, tissues, organs, and whole plants perform both hydraulic and mechanical functions. The morphological alterations that affect dual functionality are varied: individual cells can have altered morphology; tissues can have altered partitioning to functions or altered cell alignment; and organs and whole plants can differ in their allocation to different tissues, or in the geometric distribution of the tissues they have. A hierarchical model emphasizes that morphological traits influence the hydraulic or mechanical properties; the properties, combined with the plant unit's environment, then influence the performance of that plant unit. As a special case, we discuss the mechanisms by which the proxy property wood density has strong correlations to performance but without direct causality. Traits and properties influence multiple aspects of performance, and there can be mutual compensations such that similar performance occurs. This compensation emphasizes that natural selection acts on, and a plant's viability is determined by, its performance, rather than its contributing traits and properties. Continued research on the relationships among traits, and on their effects on multiple aspects of performance, will help us better predict, manage, and select plant material for success under multiple stresses in the future. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

Merging the "Morphology-Performance-Fitness" Paradigm and Life-History Theory in the Eagle Lake Garter Snake Research Project.

PubMed

Addis, Elizabeth A; Gangloff, Eric J; Palacios, Maria G; Carr, Katherine E; Bronikowski, Anne M

2017-08-01

The morphology-performance-fitness paradigm for testing selection on morphological traits has seen decades of successful application. At the same time, life-history approaches using matrix methods and perturbation studies have also allowed the direct estimate of selection acting on vital rates and the traits that comprise them. Both methodologies have been successfully applied to the garter snakes of the long-term Eagle Lake research project to reveal selection on morphology, such as color pattern, number of vertebrae, and gape size; and life-history traits such as birth size, growth rates, and juvenile survival. Here we conduct a reciprocal transplant study in a common laboratory environment to study selection on morphology and life-history. To place our results in the ecomorphology paradigm, we measure performance outcomes (feeding rates, growth, insulin-like growth factor 1 titers) of morphological variation (body size, condition) and their fitness consequences for juvenile survival-a trait that has large fitness sensitivities in these garter snake populations, and therefore is thought to be subject to strong selection. To better merge these two complementary theories, we end by discussing our findings in a nexus of morphology-performance-fitness-life history to highlight what these approaches, when combined, can reveal about selection in the wild. © The Author 2017. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

Neurochemical, morphologic, and laminar characterization of cortical projection neurons in the cingulate motor areas of the macaque monkey

NASA Technical Reports Server (NTRS)

Nimchinsky, E. A.; Hof, P. R.; Young, W. G.; Morrison, J. H.; Bloom, F. E. (Principal Investigator)

1996-01-01

The primate cingulate gyrus contains multiple cortical areas that can be distinguished by several neurochemical features, including the distribution of neurofilament protein-enriched pyramidal neurons. In addition, connectivity and functional properties indicate that there are multiple motor areas in the cortex lining the cingulate sulcus. These motor areas were targeted for analysis of potential interactions among regional specialization, connectivity, and cellular characteristics such as neurochemical profile and morphology. Specifically, intracortical injections of retrogradely transported dyes and intracellular injection were combined with immunocytochemistry to investigate neurons projecting from the cingulate motor areas to the putative forelimb region of the primary motor cortex, area M1. Two separate groups of neurons projecting to area M1 emanated from the cingulate sulcus, one anterior and one posterior, both of which furnished commissural and ipsilateral connections with area M1. The primary difference between the two populations was laminar origin, with the anterior projection originating largely in deep layers, and the posterior projection taking origin equally in superficial and deep layers. With regard to cellular morphology, the anterior projection exhibited more morphologic diversity than the posterior projection. Commissural projections from both anterior and posterior fields originated largely in layer VI. Neurofilament protein distribution was a reliable tool for localizing the two projections and for discriminating between them. Comparable proportions of the two sets of projection neurons contained neurofilament protein, although the density and distribution of the total population of neurofilament protein-enriched neurons was very different in the two subareas of origin. Within a projection, the participating neurons exhibited a high degree of morphologic heterogeneity, and no correlation was observed between somatodendritic morphology and neurofilament protein content. Thus, although the neurons that provide the anterior and posterior cingulate motor projections to area M1 differ morphologically and in laminar origin, their neurochemical profiles are similar with respect to neurofilament protein. This suggests that neurochemical phenotype may be a more important unifying feature for corticocortical projections than morphology.

Testing Phylogenetic Hypotheses of the Subgenera of the Freshwater Crayfish Genus Cambarus (Decapoda: Cambaridae)

PubMed Central

Breinholt, Jesse W.; Porter, Megan L.; Crandall, Keith A.

2012-01-01

Background The genus Cambarus is one of three most species rich crayfish genera in the Northern Hemisphere. The genus has its center of diversity in the Southern Appalachians of the United States and has been divided into 12 subgenera. Using Cambarus we test the correspondence of subgeneric designations based on morphology used in traditional crayfish taxonomy to the underlying evolutionary history for these crayfish. We further test for significant correlation and explanatory power of geographic distance, taxonomic model, and a habitat model to estimated phylogenetic distance with multiple variable regression. Methodology/Principal Findings We use three mitochondrial and one nuclear gene regions to estimate the phylogenetic relationships for species within the genus Cambarus and test evolutionary hypotheses of relationships and associated morphological and biogeographical hypotheses. Our resulting phylogeny indicates that the genus Cambarus is polyphyletic, however we fail to reject the monophyly of Cambarus with a topology test. The majority of the Cambarus subgenera are rejected as monophyletic, suggesting the morphological characters used to define those taxa are subject to convergent evolution. While we found incongruence between taxonomy and estimated phylogenetic relationships, a multiple model regression analysis indicates that taxonomy had more explanatory power of genetic relationships than either habitat or geographic distance. Conclusions We find convergent evolution has impacted the morphological features used to delimit Cambarus subgenera. Studies of the crayfish genus Orconectes have shown gonopod morphology used to delimit subgenera is also affected by convergent evolution. This suggests that morphological diagnoses based on traditional crayfish taxonomy might be confounded by convergent evolution across the cambarids and has little utility in diagnosing relationships or defining natural groups. We further suggest that convergent morphological evolution appears to be a common occurrence in invertebrates suggesting the need for careful phylogenetically based interpretations of morphological evolution in invertebrate systematics. PMID:23049950

Can we apply the MRI BI-RADS lexicon morphology descriptors on contrast-enhanced spectral mammography?

PubMed

Kamal, Rasha M; Helal, Maha H; Mansour, Sahar M; Haggag, Marwa A; Nada, Omniya M; Farahat, Iman G; Alieldin, Nelly H

2016-07-12

To assess the feasibility of using the MRI breast imaging reporting and data system (BI-RADS) lexicon morphology descriptors to characterize enhancing breast lesions identified on contrast-enhanced spectral mammography (CESM). The study is a retrospective analysis of the morphology descriptors of 261 enhancing breast lesions identified on CESM in 239 patients. We presented the morphological categorization of the included lesions into focus, mass and non-mass. Further classifications included (1) the multiplicity for "focus" category, (2) the shape, margin and internal enhancement for "mass" category and (3) the distribution and internal enhancement for "non-mass" category. Each morphology descriptor was evaluated individually (irrespective of all other descriptors) by calculating its sensitivity, specificity, positive-predictive value (PPV) and negative-predictive value (NPV) and likelihood ratios (LRs). The study included 68/261 (26.1%) benign lesions and 193/261 (73.9%) malignant lesions. Intensely enhancing foci, whether single (7/12, 58.3%) or multiple (2/12, 16.7%), were malignant. Descriptors of "irregular"-shape (PPV: 92.4%) and "non-circumscribed" margin (odds ratio: 55.2, LR positive: 4.77; p-value: <0.001) were more compatible with malignancy. Internal mass enhancement patterns showed a very low specificity (58.0%) and NPV (40.0%). Non-mass enhancement (NME) was detected in 81/261 lesions. Asymmetrical NME in 81% (n = 52/81) lesions was malignant lesions and internal enhancement patterns indicative of malignancy were the heterogeneous and clumped ones. We can apply the MRI morphology descriptors to characterize lesions on CESM, but with few expectations. In many situations, irregular-shaped, non-circumscribed masses and NME with focal, ductal or segmental distribution and heterogeneous or clumped enhancement are the most suggestive descriptors of malignant pathologies. (1) The MRI BI-RADS lexicon morphology descriptors can be applied in the characterization of enhancing lesions on CESM with a few exceptions. (2) Multiple bilateral intensely enhancing foci should not be included under the normal background parenchymal enhancement unless they are proved to be benign by biopsy. (3) Mass lesion features that indicated malignancy were irregular-shaped, spiculated and irregular margins and heterogeneous internal enhancement patterns. The rim enhancement pattern should not be considered as a descriptor of malignant lesions unless CESM is coupled with an ultrasound examination.

Can we apply the MRI BI-RADS lexicon morphology descriptors on contrast-enhanced spectral mammography?

PubMed Central

Kamal, Rasha M; Helal, Maha H; Haggag, Marwa A; Nada, Omniya M; Farahat, Iman G; Alieldin, Nelly H

2016-01-01

Objective: To assess the feasibility of using the MRI breast imaging reporting and data system (BI-RADS) lexicon morphology descriptors to characterize enhancing breast lesions identified on contrast-enhanced spectral mammography (CESM). Methods: The study is a retrospective analysis of the morphology descriptors of 261 enhancing breast lesions identified on CESM in 239 patients. We presented the morphological categorization of the included lesions into focus, mass and non-mass. Further classifications included (1) the multiplicity for “focus” category, (2) the shape, margin and internal enhancement for “mass” category and (3) the distribution and internal enhancement for “non-mass” category. Each morphology descriptor was evaluated individually (irrespective of all other descriptors) by calculating its sensitivity, specificity, positive-predictive value (PPV) and negative-predictive value (NPV) and likelihood ratios (LRs). Results: The study included 68/261 (26.1%) benign lesions and 193/261 (73.9%) malignant lesions. Intensely enhancing foci, whether single (7/12, 58.3%) or multiple (2/12, 16.7%), were malignant. Descriptors of “irregular”-shape (PPV: 92.4%) and “non-circumscribed” margin (odds ratio: 55.2, LR positive: 4.77; p-value: <0.001) were more compatible with malignancy. Internal mass enhancement patterns showed a very low specificity (58.0%) and NPV (40.0%). Non-mass enhancement (NME) was detected in 81/261 lesions. Asymmetrical NME in 81% (n = 52/81) lesions was malignant lesions and internal enhancement patterns indicative of malignancy were the heterogeneous and clumped ones. Conclusion: We can apply the MRI morphology descriptors to characterize lesions on CESM, but with few expectations. In many situations, irregular-shaped, non-circumscribed masses and NME with focal, ductal or segmental distribution and heterogeneous or clumped enhancement are the most suggestive descriptors of malignant pathologies. Advances in knowledge: (1) The MRI BI-RADS lexicon morphology descriptors can be applied in the characterization of enhancing lesions on CESM with a few exceptions. (2) Multiple bilateral intensely enhancing foci should not be included under the normal background parenchymal enhancement unless they are proved to be benign by biopsy. (3) Mass lesion features that indicated malignancy were irregular-shaped, spiculated and irregular margins and heterogeneous internal enhancement patterns. The rim enhancement pattern should not be considered as a descriptor of malignant lesions unless CESM is coupled with an ultrasound examination. PMID:27327403

Gene silencing reveals multiple functions of Na+/K+-ATPase in the salmon louse (Lepeophtheirus salmonis).

PubMed

Komisarczuk, Anna Z; Kongshaug, Heidi; Nilsen, Frank

2018-02-01

Na + /K + -ATPase has a key function in a variety of physiological processes including membrane excitability, osmoregulation, regulation of cell volume, and transport of nutrients. While knowledge about Na + /K + -ATPase function in osmoregulation in crustaceans is extensive, the role of this enzyme in other physiological and developmental processes is scarce. Here, we report characterization, transcriptional distribution and likely functions of the newly identified L. salmonis Na + /K + -ATPase (LsalNa + /K + -ATPase) α subunit in various developmental stages. The complete mRNA sequence was identified, with 3003 bp open reading frame encoding a putative protein of 1001 amino acids. Putative protein sequence of LsalNa + /K + -ATPase revealed all typical features of Na + /K + -ATPase and demonstrated high sequence identity to other invertebrate and vertebrate species. Quantitative RT-PCR analysis revealed higher LsalNa + /K + -ATPase transcript level in free-living stages in comparison to parasitic stages. In situ hybridization analysis of copepodids and adult lice revealed LsalNa + /K + -ATPase transcript localization in a wide variety of tissues such as nervous system, intestine, reproductive system, and subcuticular and glandular tissue. RNAi mediated knock-down of LsalNa + /K + -ATPase caused locomotion impairment, and affected reproduction and feeding. Morphological analysis of dsRNA treated animals revealed muscle degeneration in larval stages, severe changes in the oocyte formation and maturation in females and abnormalities in tegmental glands. Thus, the study represents an important foundation for further functional investigation and identification of physiological pathways in which Na + /K + -ATPase is directly or indirectly involved. Copyright © 2018 Elsevier Inc. All rights reserved.

Longli is not a hybrid of longan and lychee as revealed by genome size analysis and trichome morphology

USDA-ARS?s Scientific Manuscript database

Lychee, longan, longli, and rambutan are closely related, commercially important fruit trees in the Sapindaceae family. Longli fruits are morphologically similar to both lychee and longan, displaying a yellow-brown pericarp like longan, and small, sharp protuberances like lychee. These similarities ...

Awareness of Derivation and Compounding in Chinese-English Biliteracy Acquisition

ERIC Educational Resources Information Center

Zhang, Dongbo; Koda, Keiko

2014-01-01

This study examines the intra-and inter-lingual relationships between first and second language morphological awareness and reading comprehension among grade 6 Chinese learners of English as a foreign language in China. Morphological awareness measures covered compounding as well as derivation. Hierarchical regression analyses revealed that within…

Genotyping-by-sequencing reveals the origin of the Tunisian relatives of cultivated carrot

USDA-ARS?s Scientific Manuscript database

Knowledge of the morphological diversity of a germplasm collection is fundamental for genebank managers and plant breeders. The main objective of this work was to characterize 33 landraces of carrot from 13 different regions of Tunisia, based on 34 agro-morphological characters related to leaves and...

Aureobasidium pullulans morphology: two adapted polysaccharide stains.

PubMed

Oller, Anna R

2005-12-01

Morphological stages of Aureobasidium pullulans were investigated utilizing different media ingredients and were visualized by bright-field microscopy. A polysaccharide stain was developed to stain chlamydospores, cell walls, hyphae, and conidia, since current staining techniques do not reveal subcellular details to identify fungi, especially those that exhibit polysaccharide secretions.

What Do Graded Effects of Semantic Transparency Reveal about Morphological Processing?

ERIC Educational Resources Information Center

Feldman, Laurie Beth; Soltano, Emily G.; Pastizzo, Matthew J.; Francis, Sarah E.

2004-01-01

We examined the influence of semantic transparency on morphological facilitation in English in three lexical decision experiments. Decision latencies to visual targets (e.g., CASUALNESS) were faster after semantically transparent (e.g., CASUALLY) than semantically opaque (e.g., CASUALTY) primes whether primes were auditory and presented…

Morphological, molecular and ecological aspects of the South American hypogeous fungi Alpova austroalnicola sp. nov.

Treesearch

Eduardo R. Nouhra; Laura S. Domínguez; Alejandra G. Becerra; James M. Trappe

2005-01-01

Field studies in Argentina's Yunga District revealed Alpova austroalnicola sp. nov., a hypogeous fungus associated with Alnus acuminata ssp, acuminata. Morphological and molecular studies based on amplification and sequencing of the nuclear LSU rDNA gene showed its unique identity within ...

Morphological awareness and reading comprehension: Examining mediating factors.

PubMed

Levesque, Kyle C; Kieffer, Michael J; Deacon, S Hélène

2017-08-01

The relation between morphological awareness-defined as the awareness of and ability to manipulate the smallest units of meaning in language-and reading comprehension remains in need of specification. In this study, we evaluated four potential intervening variables through which morphological awareness may contribute indirectly to reading comprehension. We assessed word reading and vocabulary as well as children's ability to read and analyze the meaning of morphologically complex words (morphological decoding and morphological analysis, respectively). Controls of phonological awareness and nonverbal ability were included in the model. Participants were 221 English-speaking children in Grade 3. Multivariate path analyses revealed evidence of two indirect relations and one direct relation between morphological awareness and reading comprehension. In the first indirect path, morphological awareness contributed to morphological decoding, which then influenced word reading and finally reading comprehension. In a second indirect path, morphological awareness contributed to morphological analysis, which contributed to reading comprehension. Finally, in a direct path, morphological awareness contributed to reading comprehension beyond all other variables. These findings inform as to the potential mechanisms underlying the relation between morphological awareness and reading comprehension in children. Copyright © 2017 Elsevier Inc. All rights reserved.

A Conserved Developmental Patterning Network Produces Quantitatively Different Output in Multiple Species of Drosophila

PubMed Central

Meyer, Miriah; Wunderlich, Zeba; Simirenko, Lisa; Luengo Hendriks, Cris L.; Keränen, Soile V. E.; Henriquez, Clara; Knowles, David W.; Biggin, Mark D.; Eisen, Michael B.; DePace, Angela H.

2011-01-01

Differences in the level, timing, or location of gene expression can contribute to alternative phenotypes at the molecular and organismal level. Understanding the origins of expression differences is complicated by the fact that organismal morphology and gene regulatory networks could potentially vary even between closely related species. To assess the scope of such changes, we used high-resolution imaging methods to measure mRNA expression in blastoderm embryos of Drosophila yakuba and Drosophila pseudoobscura and assembled these data into cellular resolution atlases, where expression levels for 13 genes in the segmentation network are averaged into species-specific, cellular resolution morphological frameworks. We demonstrate that the blastoderm embryos of these species differ in their morphology in terms of size, shape, and number of nuclei. We present an approach to compare cellular gene expression patterns between species, while accounting for varying embryo morphology, and apply it to our data and an equivalent dataset for Drosophila melanogaster. Our analysis reveals that all individual genes differ quantitatively in their spatio-temporal expression patterns between these species, primarily in terms of their relative position and dynamics. Despite many small quantitative differences, cellular gene expression profiles for the whole set of genes examined are largely similar. This suggests that cell types at this stage of development are conserved, though they can differ in their relative position by up to 3–4 cell widths and in their relative proportion between species by as much as 5-fold. Quantitative differences in the dynamics and relative level of a subset of genes between corresponding cell types may reflect altered regulatory functions between species. Our results emphasize that transcriptional networks can diverge over short evolutionary timescales and that even small changes can lead to distinct output in terms of the placement and number of equivalent cells. PMID:22046143

Species Delimitation and Lineage Separation History of a Species Complex of Aspens in China

PubMed Central

Zheng, Honglei; Fan, Liqiang; Milne, Richard I.; Zhang, Lei; Wang, Yaling; Mao, Kangshan

2017-01-01

Species delimitation in tree species is notoriously challenging due to shared polymorphisms among species. An integrative survey that considers multiple operational criteria is a possible solution, and we aimed to test it in a species complex of aspens in China. Genetic [four chloroplast DNA (cpDNA) fragments and 14 nuclear microsatellite loci (nSSR)] and morphological variations were collected for 76 populations and 53 populations, respectively, covering the major geographic distribution of the Populus davidiana-rotundifolia complex. Bayesian clustering, analysis of molecular variance (AMOVA), Principle Coordinate Analysis (PCoA), ecological niche modeling (ENM), and gene flow (migrants per generation), were employed to detect and test genetic clustering, morphological and habitat differentiation, and gene flow between/among putative species. The nSSR data and ENM suggested that there are two separately evolving meta-population lineages that correspond to P. davidiana (pd) and P. rotundifolia (pr). Furthermore, several lines of evidence supported a subdivision of P. davidiana into Northeastern (NEC) and Central-North (CNC) groups, yet they are still functioning as one species. CpDNA data revealed that five haplotype clades formed a pattern of [pdNEC, ((pdCNC, pr), (pdCNC, pr))], but most haplotypes are species-specific. Meanwhile, PCA based on morphology suggested a closer relationship between the CNC group (P. davidiana) and P. rontundifolia. Discrepancy of nSSR and ENM vs. cpDNA and morphology could have reflected a complex lineage divergence and convergence history. P. davidiana and P. rotundifolia can be regarded as a recently diverged species pair that experienced parapatric speciation due to ecological differentiation in the face of gene flow. Our findings highlight the importance of integrative surveys at population level, as we have undertaken, is an important approach to detect the boundary of a group of species that have experienced complex evolutionary history. PMID:28377782

Convergent adaptive radiations in Madagascan and Asian ranid frogs reveal covariation between larval and adult traits

PubMed Central

Bossuyt, Franky; Milinkovitch, Michel C.

2000-01-01

Recent studies have reported that independent adaptive radiations can lead to identical ecomorphs. Our phylogenetic analyses of nuclear and mitochondrial DNA sequences here indicate that a major radiation of ranid frogs on Madagascar produced morphological, physiological, and developmental characters that are remarkably similar to those that independently evolved on the Indian subcontinent. We demonstrate further that, in several cases, adult and larval stages each evolved sets of characters which are not only convergent between independent lineages, but also allowed both developmental stages to invade the same adaptive zone. It is likely that such covariations are produced by similar selective pressures on independent larval and adult characters rather than by genetic or functional linkage. We briefly discuss why larval/adult covariations might constitute an important evolutionary phenomenon in species for which more than one developmental stage potentially has access to multiple environmental conditions. PMID:10841558

Amniotic-Fluid Stem Cells: Growth Dynamics and Differentiation Potential after a CD-117-Based Selection Procedure

PubMed Central

Arnhold, S.; Glüer, S.; Hartmann, K.; Raabe, O.; Addicks, K.; Wenisch, S.; Hoopmann, M.

2011-01-01

Amniotic fluid (AF) has become an interesting source of fetal stem cells. However, AF contains heterogeneous and multiple, partially differentiated cell types. After isolation from the amniotic fluid, cells were characterized regarding their morphology and growth dynamics. They were sorted by magnetic associated cell sorting using the surface marker CD 117. In order to show stem cell characteristics such as pluripotency and to evaluate a possible therapeutic application of these cells, AF fluid-derived stem cells were differentiated along the adipogenic, osteogenic, and chondrogenic as well as the neuronal lineage under hypoxic conditions. Our findings reveal that magnetic associated cell sorting (MACS) does not markedly influence growth characteristics as demonstrated by the generation doubling time. There was, however, an effect regarding an altered adipogenic, osteogenic, and chondrogenic differentiation capacity in the selected cell fraction. In contrast, in the unselected cell population neuronal differentiation is enhanced. PMID:21437196

Adenoviruses as a model in the study of the effect of space flight factors

NASA Astrophysics Data System (ADS)

Nosach, L. M.; Povnitsa, O. Yu.; Zhovnovata, V. L.

Simulated microgravity conditions, independently of multiplicity of infection, does not influence the reproduction of adenoviruses in cells which were clinorotated for 48 hours after adsorption of virus. The incubation of infected cells before clinorotation under static conditions at a temperature of 4 °C for three days (the conditions for keeping cells before the flight) does not change the number of infected cells relatively to control, but some changes of cell morphology are revealed, namely round off and aggregation of cells. The adenoviruses which were exposed in the medium keep infectivity under the conditions of clinorotation at 4 and 20-22 °C over prolonged periods (90 and 60 days, respectively). A model is elaborated for investigation of the influence of space flight factors on the interaction of the adenovirus and Epstein-Barr virus genomes at combined infection of limphoblastoid cells.

Cryo-Scanning Electron Microscopy of Captured Cirrus Ice Particles

NASA Astrophysics Data System (ADS)

Magee, N. B.; Boaggio, K.; Bandamede, M.; Bancroft, L.; Hurler, K.

2016-12-01

We present the latest collection of high-resolution cryo-scanning electron microscopy images and microanalysis of cirrus ice particles captured by high-altitude balloon (ICE-Ball, see abstracts by K. Boaggio and M. Bandamede). Ice particle images and sublimation-residues are derived from particles captured during approximately 15 balloon flights conducted in Pennsylvania and New Jersey over the past 12 months. Measurements include 3D digital elevation model reconstructions of ice particles, and associated statistical analyses of entire particles and particle sub-facets and surfaces. This 3D analysis reveals that morphologies of most ice particles captured deviate significantly from ideal habits, and display geometric complexity and surface roughness at multiple measureable scales, ranging from 100's nanometers to 100's of microns. The presentation suggests potential a path forward for representing scattering from a realistically complex array of ice particle shapes and surfaces.

Molecular ecology of hydrothermal vent microbial communities.

PubMed

Jeanthon, C

2000-02-01

The study of the structure and diversity of hydrothermal vent microbial communities has long been restricted to the morphological description of microorganisms and the use of enrichment culture-based techniques. Until recently the identification of the culturable fraction required the isolation of pure cultures followed by testing for multiple physiological and biochemical traits. However, peculiar inhabitants of the hydrothermal ecosystem such as the invertebrate endosymbionts and the dense microbial mat filaments have eluded laboratory cultivation. Substantial progress has been achieved in recent years in techniques for the identification of microorganisms in natural environments. Application of molecular approaches has revealed the existence of unique and previously unrecognized microorganisms. These have provided fresh insight into the ecology, diversity and evolution of mesophilic and thermophilic microbial communities from the deep-sea hydrothermal ecosystem. This review reports the main discoveries made through the introduction of these powerful techniques in the study of deep-sea hydrothermal vent microbiology.

Computation material science of structural-phase transformation in casting aluminium alloys

NASA Astrophysics Data System (ADS)

Golod, V. M.; Dobosh, L. Yu

2017-04-01

Successive stages of computer simulation the formation of the casting microstructure under non-equilibrium conditions of crystallization of multicomponent aluminum alloys are presented. On the basis of computer thermodynamics and heat transfer during solidification of macroscale shaped castings are specified the boundary conditions of local heat exchange at mesoscale modeling of non-equilibrium formation the solid phase and of the component redistribution between phases during coalescence of secondary dendrite branches. Computer analysis of structural - phase transitions based on the principle of additive physico-chemical effect of the alloy components in the process of diffusional - capillary morphological evolution of the dendrite structure and the o of local dendrite heterogeneity which stochastic nature and extent are revealed under metallographic study and modeling by the Monte Carlo method. The integrated computational materials science tools at researches of alloys are focused and implemented on analysis the multiple-factor system of casting processes and prediction of casting microstructure.

Rare occurrence of heart lesions in Pacific oysters Crassostrea gigas caused by an unknown bacterial infection.

PubMed

Meyer, Gary R; Lowe, Geoffrey J; Bower, Susan M

2017-09-20

On rare occasions, small cream-coloured cysts have been observed in the heart and pericardial cavity of Pacific oysters Crassostrea gigas from British Columbia, Canada. Histopathology revealed the presence of large colonies of bacteria (up to 800 µm in diameter) causing significant host response and hypertrophy of the heart epithelium. The causative bacteria were characterized as follows: Gram-negative, coccoid to small rod-shaped, typically <1.5 µm in size, cell walls highly endowed with surface fimbriae and division via binary fission. Although these bacteria shared some morphological characteristics with the order Rickettsiales, they did not require an intracellular existence for multiplication. Unfortunately, a cultured isolate was not available, and a retrospective attempt to further characterize the bacteria using DNA sequence analysis of a fragment from the 16S rDNA region proved to be uninformative.

The Developmental Process of the Growing Motile Ciliary Tip Region.

PubMed

Reynolds, Matthew J; Phetruen, Tanaporn; Fisher, Rebecca L; Chen, Ke; Pentecost, Brian T; Gomez, George; Ounjai, Puey; Sui, Haixin

2018-05-22

Eukaryotic motile cilia/flagella play vital roles in various physiological processes in mammals and some protists. Defects in cilia formation underlie multiple human disorders, known as ciliopathies. The detailed processes of cilia growth and development are still far from clear despite extensive studies. In this study, we characterized the process of cilium formation (ciliogenesis) by investigating the newly developed motile cilia of deciliated protists using complementary techniques in electron microscopy and image analysis. Our results demonstrated that the distal tip region of motile cilia exhibit progressive morphological changes as cilia develop. This developmental process is time-dependent and continues after growing cilia reach their full lengths. The structural analysis of growing ciliary tips revealed that B-tubules of axonemal microtubule doublets terminate far away from the tip end, which is led by the flagellar tip complex (FTC), demonstrating that the FTC might not directly mediate the fast turnover of intraflagellar transport (IFT).

Nuclear and mitochondrial markers reveal evidence for genetically segregated cryptic speciation in giant Pacific octopuses from Prince William Sound, Alaska

USGS Publications Warehouse

Toussaint, Rebecca K.; Scheel, David; Sage, G.K.; Talbot, S.L.

2012-01-01

Multiple species of large octopus are known from the north Pacific waters around Japan, however only one large species is known in the Gulf of Alaska (the giant Pacific octopus, Enteroctopus dofleini). Current taxonomy of E. dofleini is based on geographic and morphological characteristics, although with advances in genetic technology that is changing. Here, we used two mitochondrial genes (cytochrome b and cytochrome oxidase I), three nuclear genes (rhodopsin, octopine dehydrogenase, and paired-box 6), and 18 microsatellite loci for phylogeographic and phylogenetic analyses of octopuses collected from across southcentral and the eastern Aleutian Islands (Dutch Harbor), Alaska. Our results suggest the presence of a cryptic Enteroctopus species that is allied to, but distinguished from E. dofleini in Prince William Sound, Alaska. Existence of an undescribed and previously unrecognized taxon raises important questions about the taxonomy of octopus in southcentral Alaska waters.

hamlet, a binary genetic switch between single- and multiple- dendrite neuron morphology.

PubMed

Moore, Adrian W; Jan, Lily Yeh; Jan, Yuh Nung

2002-08-23

The dendritic morphology of neurons determines the number and type of inputs they receive. In the Drosophila peripheral nervous system (PNS), the external sensory (ES) neurons have a single nonbranched dendrite, whereas the lineally related multidendritic (MD) neurons have extensively branched dendritic arbors. We report that hamlet is a binary genetic switch between these contrasting morphological types. In hamlet mutants, ES neurons are converted to an MD fate, whereas ectopic hamlet expression in MD precursors results in transformation of MD neurons into ES neurons. Moreover, hamlet expression induced in MD neurons undergoing dendrite outgrowth drastically reduces arbor branching.

Homoplasious colony morphology and mito-nuclear phylogenetic discordance among Eastern Pacific octocorals.

PubMed

Ament-Velásquez, Sandra L; Breedy, Odalisca; Cortés, Jorge; Guzman, Hector M; Wörheide, Gert; Vargas, Sergio

2016-05-01

Octocorals are a diverse and ecologically important group of cnidarians. However, the phylogenetic relationships of many octocoral groups are not well understood and are based mostly on mitochondrial sequence data. In addition, the discovery and description of new gorgonian species displaying unusual or intermediate morphologies and uncertain phylogenetic affinities further complicates the study of octocoral systematics and raises questions about the role played by processes such as plasticity, crypsis, and convergence in the evolution of this group of organisms. Here, we use nuclear (i.e. 28S rDNA) and mitochondrial (mtMutS) markers and a sample of Eastern Pacific gorgonians thought to be remarkable from a morphological point of view to shed light on the morphological diversification among these organisms. Our study reveals the loss of the anastomosed colony morphology in two unrelated lineages of the seafan genus Pacifigorgia and offers strong evidence for the independent evolution of a whip-like morphology in two lineages of Eastern Pacific Leptogorgia. Additionally, our data revealed one instance of mito-nuclear discordance in the genera Leptogorgia and Eugorgia, which may be the results of incomplete lineage sorting or ancient hybridization-introgression events. Our study stresses the importance of comprehensive taxonomic sampling and the use of independent sources of evidence to address the phylogenetic relationships and clarifying the evolution of octocorals. Copyright © 2016 Elsevier Inc. All rights reserved.

Revealing 3D Ultrastructure and Morphology of Stem Cell Spheroids by Electron Microscopy.

PubMed

Jaros, Josef; Petrov, Michal; Tesarova, Marketa; Hampl, Ales

2017-01-01

Cell culture methods have been developed in efforts to produce biologically relevant systems for developmental and disease modeling, and appropriate analytical tools are essential. Knowledge of ultrastructural characteristics represents the basis to reveal in situ the cellular morphology, cell-cell interactions, organelle distribution, niches in which cells reside, and many more. The traditional method for 3D visualization of ultrastructural components, serial sectioning using transmission electron microscopy (TEM), is very labor-intensive due to contentious TEM slice preparation and subsequent image processing of the whole collection. In this chapter, we present serial block-face scanning electron microscopy, together with complex methodology for spheroid formation, contrasting of cellular compartments, image processing, and 3D visualization. The described technique is effective for detailed morphological analysis of stem cell spheroids, organoids, as well as organotypic cell cultures.

Organogenesis in deep time: A problem in genomics, development, and paleontology.

PubMed

Pieretti, Joyce; Gehrke, Andrew R; Schneider, Igor; Adachi, Noritaka; Nakamura, Tetsuya; Shubin, Neil H

2015-04-21

The fossil record is a unique repository of information on major morphological transitions. Increasingly, developmental, embryological, and functional genomic approaches have also conspired to reveal evolutionary trajectory of phenotypic shifts. Here, we use the vertebrate appendage to demonstrate how these disciplines can mutually reinforce each other to facilitate the generation and testing of hypotheses of morphological evolution. We discuss classical theories on the origins of paired fins, recent data on regulatory modulations of fish fins and tetrapod limbs, and case studies exploring the mechanisms of digit loss in tetrapods. We envision an era of research in which the deep history of morphological evolution can be revealed by integrating fossils of transitional forms with direct experimentation in the laboratory via genome manipulation, thereby shedding light on the relationship between genes, developmental processes, and the evolving phenotype.

3D morphology of Au and Au@Ag nanobipyramids

NASA Astrophysics Data System (ADS)

Burgin, Julien; Florea, Ileana; Majimel, Jérôme; Dobri, Adam; Ersen, Ovidiu; Tréguer-Delapierre, Mona

2012-02-01

The morphologies of Au and Au@Ag nanobipyramids were investigated using electron tomography. The 3D reconstruction reveals that the Au bipyramids have an irregular six-fold twinning structure with highly stepped dominant {151} facets. These short steps/edges stabilized via surface adsorbed CTAB favor the growth of silver on the lateral facets leading to strong blue shifts in longitudinal plasmon surface resonance.The morphologies of Au and Au@Ag nanobipyramids were investigated using electron tomography. The 3D reconstruction reveals that the Au bipyramids have an irregular six-fold twinning structure with highly stepped dominant {151} facets. These short steps/edges stabilized via surface adsorbed CTAB favor the growth of silver on the lateral facets leading to strong blue shifts in longitudinal plasmon surface resonance. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr11454b

Modelling rate distributions using character compatibility: implications for morphological evolution among fossil invertebrates.

PubMed

Wagner, Peter J

2012-02-23

Rate distributions are important considerations when testing hypotheses about morphological evolution or phylogeny. They also have implications about general processes underlying character evolution. Molecular systematists often assume that rates are Poisson processes with gamma distributions. However, morphological change is the product of multiple probabilistic processes and should theoretically be affected by hierarchical integration of characters. Both factors predict lognormal rate distributions. Here, a simple inverse modelling approach assesses the best single-rate, gamma and lognormal models given observed character compatibility for 115 invertebrate groups. Tests reject the single-rate model for nearly all cases. Moreover, the lognormal outperforms the gamma for character change rates and (especially) state derivation rates. The latter in particular is consistent with integration affecting morphological character evolution.

Deaf college students' mathematical skills relative to morphological knowledge, reading level, and language proficiency.

PubMed

Kelly, Ronald R; Gaustad, Martha G

2007-01-01

This study of deaf college students examined specific relationships between their mathematics performance and their assessed skills in reading, language, and English morphology. Simple regression analyses showed that deaf college students' language proficiency scores, reading grade level, and morphological knowledge regarding word segmentation and meaning were all significantly correlated with both the ACT Mathematics Subtest and National Technical Institute for the Deaf (NTID) Mathematics Placement Test scores. Multiple regression analyses identified the best combination from among these potential independent predictors of students' performance on both the ACT and NTID mathematics tests. Additionally, the participating deaf students' grades in their college mathematics courses were significantly and positively associated with their reading grade level and their knowledge of morphological components of words.

A reservoir morphology database for the conterminous United States

USGS Publications Warehouse

Rodgers, Kirk D.

2017-09-13

The U.S. Geological Survey, in cooperation with the Reservoir Fisheries Habitat Partnership, combined multiple national databases to create one comprehensive national reservoir database and to calculate new morphological metrics for 3,828 reservoirs. These new metrics include, but are not limited to, shoreline development index, index of basin permanence, development of volume, and other descriptive metrics based on established morphometric formulas. The new database also contains modeled chemical and physical metrics. Because of the nature of the existing databases used to compile the Reservoir Morphology Database and the inherent missing data, some metrics were not populated. One comprehensive database will assist water-resource managers in their understanding of local reservoir morphology and water chemistry characteristics throughout the continental United States.

Clinical, Morphological, and Molecular Characterization of Penicillium canis sp. nov., Isolated from a Dog with Osteomyelitis

PubMed Central

Sutton, Deanna A.; Swenson, Cheryl L.; Bailey, Chris J.; Wiederhold, Nathan P.; Nelson, Nathan C.; Thompson, Elizabeth H.; Wickes, Brian L.; French, Stephanie; Fu, Jianmin; Vilar-Saavedra, Paulo

2014-01-01

Infections caused by Penicillium species are rare in dogs, and the prognosis in these cases is poor. An unknown species of Penicillium was isolated from a bone lesion in a young dog with osteomyelitis of the right ilium. Extensive diagnostic evaluation did not reveal evidence of dissemination. Resolution of lameness and clinical stability of disease were achieved with intravenous phospholipid-complexed amphotericin B initially, followed by long-term combination therapy with terbinafine and ketoconazole. A detailed morphological and molecular characterization of the mold was undertaken. Sequence analysis of the internal transcribed spacer revealed the isolate to be closely related to Penicillium menonorum and Penicillium pimiteouiense. Additional sequence analysis of β-tubulin, calmodulin, minichromosome maintenance factor, DNA-dependent RNA polymerase, and pre-rRNA processing protein revealed the isolate to be a novel species; the name Penicillium canis sp. nov. is proposed. Morphologically, smooth, ovoid conidia, a greenish gray colony color, slow growth on all media, and a failure to form ascomata distinguish this species from closely related Penicillium species. PMID:24789186

Clinical, morphological, and molecular characterization of Penicillium canis sp. nov., isolated from a dog with osteomyelitis.

PubMed

Langlois, Daniel K; Sutton, Deanna A; Swenson, Cheryl L; Bailey, Chris J; Wiederhold, Nathan P; Nelson, Nathan C; Thompson, Elizabeth H; Wickes, Brian L; French, Stephanie; Fu, Jianmin; Vilar-Saavedra, Paulo; Peterson, Stephen W

2014-07-01

Infections caused by Penicillium species are rare in dogs, and the prognosis in these cases is poor. An unknown species of Penicillium was isolated from a bone lesion in a young dog with osteomyelitis of the right ilium. Extensive diagnostic evaluation did not reveal evidence of dissemination. Resolution of lameness and clinical stability of disease were achieved with intravenous phospholipid-complexed amphotericin B initially, followed by long-term combination therapy with terbinafine and ketoconazole. A detailed morphological and molecular characterization of the mold was undertaken. Sequence analysis of the internal transcribed spacer revealed the isolate to be closely related to Penicillium menonorum and Penicillium pimiteouiense. Additional sequence analysis of β-tubulin, calmodulin, minichromosome maintenance factor, DNA-dependent RNA polymerase, and pre-rRNA processing protein revealed the isolate to be a novel species; the name Penicillium canis sp. nov. is proposed. Morphologically, smooth, ovoid conidia, a greenish gray colony color, slow growth on all media, and a failure to form ascomata distinguish this species from closely related Penicillium species. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Schwann cell-specific JAM-C-deficient mice reveal novel expression and functions for JAM-C in peripheral nerves

PubMed Central

Colom, Bartomeu; Poitelon, Yannick; Huang, Wenlong; Woodfin, Abigail; Averill, Sharon; Del Carro, Ubaldo; Zambroni, Desirée; Brain, Susan D.; Perretti, Mauro; Ahluwalia, Amrita; Priestley, John V.; Chavakis, Triantafyllos; Imhof, Beat A.; Feltri, M. Laura; Nourshargh, Sussan

2012-01-01

Junctional adhesion molecule-C (JAM-C) is an adhesion molecule expressed at junctions between adjacent endothelial and epithelial cells and implicated in multiple inflammatory and vascular responses. In addition, we recently reported on the expression of JAM-C in Schwann cells (SCs) and its importance for the integrity and function of peripheral nerves. To investigate the role of JAM-C in neuronal functions further, mice with a specific deletion of JAM-C in SCs (JAM-C SC KO) were generated. Compared to wild-type (WT) controls, JAM-C SC KO mice showed electrophysiological defects, muscular weakness, and hypersensitivity to mechanical stimuli. In addressing the underlying cause of these defects, nerves from JAM-C SC KO mice were found to have morphological defects in the paranodal region, exhibiting increased nodal length as compared to WTs. The study also reports on previously undetected expressions of JAM-C, namely on perineural cells, and in line with nociception defects of the JAM-C SC KO animals, on finely myelinated sensory nerve fibers. Collectively, the generation and characterization of JAM-C SC KO mice has provided unequivocal evidence for the involvement of SC JAM-C in the fine organization of peripheral nerves and in modulating multiple neuronal responses.—Colom, B., Poitelon, Y., Huang, W., Woodfin, A., Averill, S., Del Carro, U., Zambroni, D., Brain, S. D., Perretti, M., Ahluwalia, A., Priestley, J. V., Chavakis, T., Imhof, B. A., Feltri, M. L., Nourshargh, S. Schwann cell-specific JAM-C-deficient mice reveal novel expression and functions for JAM-C in peripheral nerves. PMID:22090315

Identification and Analyses of AUX-IAA target genes controlling multiple pathways in developing fiber cells of Gossypium hirsutum L

PubMed Central

Nigam, Deepti; Sawant, Samir V

2013-01-01

Technological development led to an increased interest in systems biological approaches in plants to characterize developmental mechanism and candidate genes relevant to specific tissue or cell morphology. AUX-IAA proteins are important plant-specific putative transcription factors. There are several reports on physiological response of this family in Arabidopsis but in cotton fiber the transcriptional network through which AUX-IAA regulated its target genes is still unknown. in-silico modelling of cotton fiber development specific gene expression data (108 microarrays and 22,737 genes) using Algorithm for the Reconstruction of Accurate Cellular Networks (ARACNe) reveals 3690 putative AUX-IAA target genes of which 139 genes were known to be AUX-IAA co-regulated within Arabidopsis. Further AUX-IAA targeted gene regulatory network (GRN) had substantial impact on the transcriptional dynamics of cotton fiber, as showed by, altered TF networks, and Gene Ontology (GO) biological processes and metabolic pathway associated with its target genes. Analysis of the AUX-IAA-correlated gene network reveals multiple functions for AUX-IAA target genes such as unidimensional cell growth, cellular nitrogen compound metabolic process, nucleosome organization, DNA-protein complex and process related to cell wall. These candidate networks/pathways have a variety of profound impacts on such cellular functions as stress response, cell proliferation, and cell differentiation. While these functions are fairly broad, their underlying TF networks may provide a global view of AUX-IAA regulated gene expression and a GRN that guides future studies in understanding role of AUX-IAA box protein and its targets regulating fiber development. PMID:24497725

Label-free imaging of trabecular meshwork cells using Coherent Anti-Stokes Raman Scattering (CARS) microscopy

PubMed Central

Lei, Tim C.; Ammar, David A.; Masihzadeh, Omid; Gibson, Emily A.

2011-01-01

Purpose To image the human trabecular meshwork (TM) using a non-invasive, non-destructive technique without the application of exogenous label. Methods Flat-mounted TM samples from a human cadaver eye were imaged using two nonlinear optical techniques: coherent anti-Stokes Raman scattering (CARS) and two-photon autofluorescence (TPAF). In TPAF, two optical photons are simultaneously absorbed and excite molecules in the sample that then emit a higher energy photon. The signal is predominately from collagen and elastin. The CARS technique uses two laser frequencies to specifically excite carbon-hydrogen bonds, allowing the visualization of lipid-rich cell membranes. Multiple images were taken along an axis perpendicular to the surface of the TM for subsequent analysis. Results Analysis of multiple TPAF images of the TM reveals the characteristic overlapping bundles of collagen of various sizes. Simultaneous CARS imaging revealed elliptical structures of ~7×10 µm in diameter populating the meshwork which were consistent with TM cells. Irregularly shaped objects of ~4 µm diameter appeared in both the TPAF and CARS channels, and are consistent with melanin granules. Conclusions CARS techniques were successful in imaging live TM cells in freshly isolated human TM samples. Similar images have been obtained with standard histological techniques, however the method described here has the advantage of being performed on unprocessed, unfixed tissue free from the potential distortions of the fine tissue morphology that can occur due to infusion of fixatives and treatment with alcohols. CARS imaging of the TM represents a new avenue for exploring details of aqueous outflow and TM cell physiology. PMID:22025898

Shrinking pleuritis with lobar atelectasis, a morphologic variant of round atelectasis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chung-Park, M.; Tomashefski, J.F. Jr.; Cohen, A.M.

1989-04-01

Round atelectasis (shrinking pleuritis) is typically a localized process characterized by focal pleural scarring and subjacent peripheral atelectasis. We report three patients, studied at autopsy, with an unusual variant of round atelectasis, termed shrinking pleuritis with lobar atelectasis, which is characterized by lobar atelectasis, visceral pleural fibrosis involving multiple lobes, interlobar fibrous cords, pleural effusion, and nonspecific, persistent infiltrates on chest radiogram. The possible causes of shrinking pleuritis with lobar atelectasis in our patients were multiple and included environmental dust exposure, infection, uremia, and recurrent pleural effusions. Our findings support both the folding (pleural effusion) and fibrosing (pleural injury) theoriesmore » of pathogenesis of round atelectasis and emphasize the spectrum of morphologic variability in this condition.« less

Relating electronic and geometric structure of atomic layer deposited BaTiO 3 to its electrical properties

DOE PAGES

Torgersen, Jan; Acharya, Shinjita; Dadlani, Anup Lal; ...

2016-03-24

Atomic layer deposition allows the fabrication of BaTiO 3 (BTO) ultrathin films with tunable dielectric properties, which is a promising material for electronic and optical technology. Industrial applicability necessitates a better understanding of their atomic structure and corresponding properties. Through the use of element-specific X-ray absorption near edge structure (XANES) analysis, O K-edge of BTO as a function of cation composition and underlying substrate (RuO 2 and SiO 2) is revealed. By employing density functional theory and multiple scattering simulations, we analyze the distortions in BTO’s bonding environment captured by the XANES spectra. The spectral weight shifts to lower energymore » with increasing Ti content and provides an atomic scale (microscopic) explanation for the increase in leakage current density. Differences in film morphologies in the first few layers near substrate–film interfaces reveal BTO’s homogeneous growth on RuO 2 and its distorted growth on SiO 2. As a result, this work links structural changes to BTO thin-film properties and provides insight necessary for optimizing future BTO and other ternary metal oxide-based thin-film devices.« less

In-Depth View of the Structure and Growth of SnO2 Nanowires and Nanobrushes.

PubMed

Stuckert, Erin P; Geiss, Roy H; Miller, Christopher J; Fisher, Ellen R

2016-08-31

Strategic application of an array of complementary imaging and diffraction techniques is critical to determine accurate structural information on nanomaterials, especially when also seeking to elucidate structure-property relationships and their effects on gas sensors. In this work, SnO2 nanowires and nanobrushes grown via chemical vapor deposition (CVD) displayed the same tetragonal SnO2 structure as revealed via powder X-ray diffraction bulk crystallinity data. Additional characterization using a range of electron microscopy imaging and diffraction techniques, however, revealed important structure and morphology distinctions between the nanomaterials. Tailoring scanning transmission electron microscopy (STEM) modes combined with transmission electron backscatter diffraction (t-EBSD) techniques afforded a more detailed view of the SnO2 nanostructures. Indeed, upon deeper analysis of individual wires and brushes, we discovered that, despite a similar bulk structure, wires and brushes grew with different crystal faces and lattice spacings. Had we not utilized multiple STEM diffraction modes in conjunction with t-EBSD, differences in orientation related to bristle density would have been overlooked. Thus, it is only through a methodical combination of several structural analysis techniques that precise structural information can be reliably obtained.

Growth, crystalline perfection, spectral and optical characterization of a novel optical material: l-tryptophan p-nitrophenol trisolvate single crystal.

PubMed

Sivakumar, N; Srividya, J; Mohana, J; Anbalagan, G

2015-03-15

l-tryptophan p-nitrophenol trisolvate (LTPN), an organic nonlinear optical material was synthesized using ethanol-water mixed solvent and the crystals were grown by a slow solvent evaporation method. The crystal structure and morphology were studied by single crystal X-ray diffraction analysis. The crystalline perfection of the LTPN crystal was analyzed by high-resolution X-ray diffraction study. The molecular structure of the crystal was confirmed by observing the various characteristic functional groups of the material using vibrational spectroscopy. The cut-off wavelength, optical transmission, refractive index and band gap energy were determined using UV-visible data. The variation of refractive index with wavelength shows the normal behavior. The second harmonic generation of the crystal was confirmed and the efficiency was measured using Kurtz Perry powder method. Single and multiple shot methods were employed to measure surface laser damage of the crystal. The photoluminescence spectral study revealed that the emission may be associated with the radiative recombination of trapped electrons and holes. Microhardness measurements revealed that LTPN belongs to a soft material category. Copyright © 2014 Elsevier B.V. All rights reserved.

Femtosecond laser-induced cross-periodic structures on a crystalline silicon surface under low pulse number irradiation

NASA Astrophysics Data System (ADS)

Ji, Xu; Jiang, Lan; Li, Xiaowei; Han, Weina; Liu, Yang; Wang, Andong; Lu, Yongfeng

2015-01-01

A cross-patterned surface periodic structure in femtosecond laser processing of crystalline silicon was revealed under a relatively low shots (4 < N < 10) with the pulse energy slightly higher than the ablation threshold. The experimental results indicated that the cross-pattern was composed of mutually orthogonal periodic structures (ripples). Ripples with a direction perpendicular to laser polarization (R⊥) spread in the whole laser-modified region, with the periodicity around 780 nm which was close to the central wavelength of the laser. Other ripples with a direction parallel to laser polarization (R‖) were found to be distributed between two of the adjacent ripples R⊥, with a periodicity about the sub-wavelength of the irradiated laser, 390 nm. The geometrical morphology of two mutually orthogonal ripples under static femtosecond laser irradiation could be continuously rotated as the polarization directions changed, but the periodicity remained almost unchanged. The underlying physical mechanism was revealed by numerical simulations based on the finite element method. It was found that the incubation effect with multiple shots, together with the redistributed electric field after initial ablation, plays a crucial role in the generation of the cross-patterned periodic surface structures.

Quantitative Outline-based Shape Analysis and Classification of Planetary Craterforms using Supervised Learning Models

NASA Astrophysics Data System (ADS)

Slezak, Thomas Joseph; Radebaugh, Jani; Christiansen, Eric

2017-10-01

The shapes of craterform morphology on planetary surfaces provides rich information about their origins and evolution. While morphologic information provides rich visual clues to geologic processes and properties, the ability to quantitatively communicate this information is less easily accomplished. This study examines the morphology of craterforms using the quantitative outline-based shape methods of geometric morphometrics, commonly used in biology and paleontology. We examine and compare landforms on planetary surfaces using shape, a property of morphology that is invariant to translation, rotation, and size. We quantify the shapes of paterae on Io, martian calderas, terrestrial basaltic shield calderas, terrestrial ash-flow calderas, and lunar impact craters using elliptic Fourier analysis (EFA) and the Zahn and Roskies (Z-R) shape function, or tangent angle approach to produce multivariate shape descriptors. These shape descriptors are subjected to multivariate statistical analysis including canonical variate analysis (CVA), a multiple-comparison variant of discriminant analysis, to investigate the link between craterform shape and classification. Paterae on Io are most similar in shape to terrestrial ash-flow calderas and the shapes of terrestrial basaltic shield volcanoes are most similar to martian calderas. The shapes of lunar impact craters, including simple, transitional, and complex morphology, are classified with a 100% rate of success in all models. Multiple CVA models effectively predict and classify different craterforms using shape-based identification and demonstrate significant potential for use in the analysis of planetary surfaces.

Spiraling into History: A Molecular Phylogeny and Investigation of Biogeographic Origins and Floral Evolution for the Genus Costus

PubMed Central

Salzman, Shayla; Driscoll, Heather E.; Renner, Tanya; André, Thiago; Shen, Stacy; Specht, Chelsea D.

2015-01-01

Rapid radiations are notoriously difficult to resolve, yet understanding phylogenetic patterns in such lineages can be useful for investigating evolutionary processes associated with bursts of speciation and morphological diversification. Here we present an expansive molecular phylogeny of Costus L. (Costaceae Nakai) with a focus on the Neotropical species within the clade, sampling 47 of the known 51 Neotropical species and including five molecular markers for phylogenetic analysis (ITS, ETS, rps16, trnL-F, and CaM). We use the phylogenetic results to investigate shifts in pollination syndrome, with the intention of addressing potential mechanisms leading to the rapid radiation documented for this clade. Our ancestral reconstruction of pollination syndrome presents the first evidence in this genus of an evolutionary toggle in pollination morphologies, demonstrating both the multiple independent evolutions of ornithophily (bird pollination) as well as reversals to melittophily (bee pollination). We show that the ornithophilous morphology has evolved at least eight times independently with four potential reversals to melittophilous morphology, and confirm prior work showing that neither pollination syndrome defines a monophyletic lineage. Based on the current distribution for the Neotropical and African species, we reconstruct the ancestral distribution of the Neotropical clade as the Pacific Coast of Mexico and Central America. Our results indicate an historic dispersal of a bee-pollinated taxon from Africa to the Pacific Coast of Mexico/Central America, with subsequent diversification leading to the evolution of a bird-pollinated floral morphology in multiple derived lineages. PMID:26146450

'Ogura'-based 'CMS' lines with different nuclear backgrounds of cabbage revealed substantial diversity at morphological and molecular levels.

PubMed

Parkash, Chander; Kumar, Sandeep; Singh, Rajender; Kumar, Ajay; Kumar, Satish; Dey, Shyam Sundar; Bhatia, Reeta; Kumar, Raj

2018-01-01

A comprehensive study on characterization and genetic diversity analysis was carried out in 16 'Ogura'-based 'CMS' lines of cabbage using 14 agro-morphological traits and 29 SSR markers. Agro-morphological characterization depicted considerable variations for different horticultural traits studied. The genotype, ZHA-2, performed better for most of the economically important quantitative traits. Further, gross head weight (0.76), head length (0.60) and head width (0.83) revealed significant positive correlation with net head weight. Dendrogram based on 10 quantitative traits exhibited considerable diversity among different CMS lines and principle component analysis (PCA) indicated that net and gross head weight, and head length and width are the main components of divergence between 16 CMS lines of cabbage. In molecular study, a total of 58 alleles were amplified by 29 SSR primers, averaging to 2.0 alleles in each locus. High mean values of Shannon's Information index (0.62), expected (0.45) and observed (0.32) heterozygosity and polymorphic information content (0.35) depicted substantial polymorphism. Dendrogram based on Jaccard's similarity coefficient constructed two major groups and eight sub-groups, which revealed substantial diversity among different CMS lines. In overall, based on agro-morphological and molecular studies genotype RRMA, ZHA-2 and RCA were found most divergent. Hence, they have immense potential in future breeding programs for the high-yielding hybrid development in cabbage.

Chemometric investigation of light-shade effects on essential oil yield and morphology of Moroccan Myrtus communis L.

PubMed

Fadil, Mouhcine; Farah, Abdellah; Ihssane, Bouchaib; Haloui, Taoufik; Lebrazi, Sara; Zghari, Badreddine; Rachiq, Saâd

2016-01-01

To investigate the effect of environmental factors such as light and shade on essential oil yield and morphological traits of Moroccan Myrtus communis, a chemometric study was conducted on 20 individuals growing under two contrasting light environments. The study of individual's parameters by principal component analysis has shown that essential oil yield, altitude, and leaves thickness were positively correlated between them and negatively correlated with plants height, leaves length and leaves width. Principal component analysis and hierarchical cluster analysis have also shown that the individuals of each sampling site were grouped separately. The one-way ANOVA test has confirmed the effect of light and shade on essential oil yield and morphological parameters by showing a statistically significant difference between them from the shaded side to the sunny one. Finally, the multiple linear model containing main, interaction and quadratic terms was chosen for the modeling of essential oil yield in terms of morphological parameters. Sun plants have a small height, small leaves length and width, but they are thicker and richer in essential oil than shade plants which have shown almost the opposite. The highlighted multiple linear model can be used to predict essential oil yield in the studied area.

Environmental and Genetic Determinants of Colony Morphology in Yeast

PubMed Central

Granek, Joshua A.; Magwene, Paul M.

2010-01-01

Nutrient stresses trigger a variety of developmental switches in the budding yeast Saccharomyces cerevisiae. One of the least understood of such responses is the development of complex colony morphology, characterized by intricate, organized, and strain-specific patterns of colony growth and architecture. The genetic bases of this phenotype and the key environmental signals involved in its induction have heretofore remained poorly understood. By surveying multiple strain backgrounds and a large number of growth conditions, we show that limitation for fermentable carbon sources coupled with a rich nitrogen source is the primary trigger for the colony morphology response in budding yeast. Using knockout mutants and transposon-mediated mutagenesis, we demonstrate that two key signaling networks regulating this response are the filamentous growth MAP kinase cascade and the Ras-cAMP-PKA pathway. We further show synergistic epistasis between Rim15, a kinase involved in integration of nutrient signals, and other genes in these pathways. Ploidy, mating-type, and genotype-by-environment interactions also appear to play a role in the controlling colony morphology. Our study highlights the high degree of network reuse in this model eukaryote; yeast use the same core signaling pathways in multiple contexts to integrate information about environmental and physiological states and generate diverse developmental outputs. PMID:20107600

Convergent, Parallel and Correlated Evolution of Trophic Morphologies in the Subfamily Schizothoracinae from the Qinghai-Tibetan Plateau

PubMed Central

Qi, Delin; Chao, Yan; Guo, Songchang; Zhao, Lanying; Li, Taiping; Wei, Fulei; Zhao, Xinquan

2012-01-01

Schizothoracine fishes distributed in the water system of the Qinghai-Tibetan plateau (QTP) and adjacent areas are characterized by being highly adaptive to the cold and hypoxic environment of the plateau, as well as by a high degree of diversity in trophic morphology due to resource polymorphisms. Although convergent and parallel evolution are prevalent in the organisms of the QTP, it remains unknown whether similar evolutionary patterns have occurred in the schizothoracine fishes. Here, we constructed for the first time a tentative molecular phylogeny of the schizothoracine fishes based on the complete sequences of the cytochrome b gene. We employed this molecular phylogenetic framework to examine the evolution of trophic morphologies. We used Pagel's maximum likelihood method to estimate the evolutionary associations of trophic morphologies and food resource use. Our results showed that the molecular and published morphological phylogenies of Schizothoracinae are partially incongruent with respect to some intergeneric relationships. The phylogenetic results revealed that four character states of five trophic morphologies and of food resource use evolved at least twice during the diversification of the subfamily. State transitions are the result of evolutionary patterns including either convergence or parallelism or both. Furthermore, our analyses indicate that some characters of trophic morphologies in the Schizothoracinae have undergone correlated evolution, which are somewhat correlated with different food resource uses. Collectively, our results reveal new examples of convergent and parallel evolution in the organisms of the QTP. The adaptation to different trophic niches through the modification of trophic morphologies and feeding behaviour as found in the schizothoracine fishes may account for the formation and maintenance of the high degree of diversity and radiations in fish communities endemic to QTP. PMID:22470515

Meiotic recombination and spermatogenic impairment in Mus musculus domesticus carrying multiple simple Robertsonian translocations.

PubMed

Merico, V; Pigozzi, M I; Esposito, A; Merani, M S; Garagna, S

2003-01-01

We quantitatively analyzed the spermatogenic process, including evaluation of seminiferous tubules with defective cycles, rates of germ cell death and sperm morphology, in adult male mice with standard telocentric chromosomes (2n = 40, CD1 strain), homozygous (2n = 24, Mil II population) and heterozygous (2n = 24 x 40) for Robertsonian (Rb) rearrangements. The animals were analyzed at three different ages: three, five and seven months after birth. The number and position of crossover events were also determined by chiasmata counting and immunostaining with an antibody against mouse MLH1 protein. Our analysis of spermatogenesis confirms the impairment of the spermatogenic process in multiple simple heterozygotes due to both germ cell and abnormal sperm morphology. The detrimental effects exerted by Rb heterozygosities were found to be at least partially buffered with time: the frequency of defective tubules was lower and germ cell survival and sperm morphology better in 7-month-old animals than in the 3- and 5-month-old mice. While there are previously published data on germ cell death in multiple simple heterozygotes, this is the first report of a partial rescue of spermatogenesis with time. The mean frequency of MLH1 foci was lower in Rb homozygous and heterozygous mice than in mice carrying all telocentric chromosomes. The lower number of foci in Rb mice can be ascribed to a decrease in the number of multiple chiasmata and the maintenance of single chiasmata preferentially located in the terminal region of both the telocentric and metacentric chromosomes. Copyright 2003 S. Karger AG, Basel

DNA barcoding reveals a cryptic nemertean invasion in Atlantic and Mediterranean waters

NASA Astrophysics Data System (ADS)

Fernández-Álvarez, Fernando Ángel; Machordom, Annie

2013-09-01

For several groups, like nemerteans, morphology-based identification is a hard discipline, but DNA barcoding may help non-experts in the identification process. In this study, DNA barcoding is used to reveal the cryptic invasion of Pacific Cephalothrix cf. simula into Atlantic and Mediterranean coasts. Although DNA barcoding is a promising method for the identification of Nemertea, only 6 % of the known number of nemertean species is currently associated with a correct DNA barcode. Therefore, additional morphological and molecular studies are necessary to advance the utility of DNA barcoding in the characterisation of possible nemertean alien invasions.

Galaxy Morphology Revealed By SDSS: Blue Elliptical Galaxies

NASA Astrophysics Data System (ADS)

Ann, Hong Bae

The Sloan Digital Sky Survey (SDSS) reveals many new features of galaxy morphologies. Among others, the discovery of blue elliptical galaxies provides some insights into the formation and evolution of galaxies. There seems to be two types of blue elliptical galaxies. One type shows globally blue colors suggesting star formations over the entire galaxy whereas the other type shows blue core that indicates enhanced star formation in the nuclear regions. The former seems to be currently forming galaxies, while the latter is thought to be in transition stage from the blue cloud to the red sequence due to AGN feedback.

Strong signatures of selection in the domestic pig genome.

PubMed

Rubin, Carl-Johan; Megens, Hendrik-Jan; Martinez Barrio, Alvaro; Maqbool, Khurram; Sayyab, Shumaila; Schwochow, Doreen; Wang, Chao; Carlborg, Örjan; Jern, Patric; Jørgensen, Claus B; Archibald, Alan L; Fredholm, Merete; Groenen, Martien A M; Andersson, Leif

2012-11-27

Domestication of wild boar (Sus scrofa) and subsequent selection have resulted in dramatic phenotypic changes in domestic pigs for a number of traits, including behavior, body composition, reproduction, and coat color. Here we have used whole-genome resequencing to reveal some of the loci that underlie phenotypic evolution in European domestic pigs. Selective sweep analyses revealed strong signatures of selection at three loci harboring quantitative trait loci that explain a considerable part of one of the most characteristic morphological changes in the domestic pig--the elongation of the back and an increased number of vertebrae. The three loci were associated with the NR6A1, PLAG1, and LCORL genes. The latter two have repeatedly been associated with loci controlling stature in other domestic animals and in humans. Most European domestic pigs are homozygous for the same haplotype at these three loci. We found an excess of derived nonsynonymous substitutions in domestic pigs, most likely reflecting both positive selection and relaxed purifying selection after domestication. Our analysis of structural variation revealed four duplications at the KIT locus that were exclusively present in white or white-spotted pigs, carrying the Dominant white, Patch, or Belt alleles. This discovery illustrates how structural changes have contributed to rapid phenotypic evolution in domestic animals and how alleles in domestic animals may evolve by the accumulation of multiple causative mutations as a response to strong directional selection.

Strong signatures of selection in the domestic pig genome

PubMed Central

Rubin, Carl-Johan; Megens, Hendrik-Jan; Barrio, Alvaro Martinez; Maqbool, Khurram; Sayyab, Shumaila; Schwochow, Doreen; Wang, Chao; Carlborg, Örjan; Jern, Patric; Jørgensen, Claus B.; Archibald, Alan L.; Fredholm, Merete; Groenen, Martien A. M.; Andersson, Leif

2012-01-01

Domestication of wild boar (Sus scrofa) and subsequent selection have resulted in dramatic phenotypic changes in domestic pigs for a number of traits, including behavior, body composition, reproduction, and coat color. Here we have used whole-genome resequencing to reveal some of the loci that underlie phenotypic evolution in European domestic pigs. Selective sweep analyses revealed strong signatures of selection at three loci harboring quantitative trait loci that explain a considerable part of one of the most characteristic morphological changes in the domestic pig—the elongation of the back and an increased number of vertebrae. The three loci were associated with the NR6A1, PLAG1, and LCORL genes. The latter two have repeatedly been associated with loci controlling stature in other domestic animals and in humans. Most European domestic pigs are homozygous for the same haplotype at these three loci. We found an excess of derived nonsynonymous substitutions in domestic pigs, most likely reflecting both positive selection and relaxed purifying selection after domestication. Our analysis of structural variation revealed four duplications at the KIT locus that were exclusively present in white or white-spotted pigs, carrying the Dominant white, Patch, or Belt alleles. This discovery illustrates how structural changes have contributed to rapid phenotypic evolution in domestic animals and how alleles in domestic animals may evolve by the accumulation of multiple causative mutations as a response to strong directional selection. PMID:23151514

Morphological development of cellulose fibrils of a bleached eucalyptus pulp by mechanical fibrillation

Treesearch

Q.Q. Wang; J.Y. Zhu; R. Gleisner; T.A. Kuster; U. Baxa; S.E. McNeil

2012-01-01

This study reports the production of cellulose nanofibrils (CNF) from a bleached eucalyptus pulp using a commercial stone grinder. Scanning electronic microscopy and transmission electronic microscopy imaging were used to reveal morphological development of CNF at micro and nano scales, respectively. Two major structures were identified (1) highly kinked, naturally...

Morphology and vulcanizate properties of ethylene-propylene-diene rubber/ styrene-butadiene rubber blends.

PubMed

Park, Gayoung; Kim, Yun Hee; Kim, Dong Soo; Ko, Young Chun

2010-05-01

Morphology and vulcanizate properties of EPDM/SBR blends were investigated. AAHR (a mixture of aliphatic and aromatic hydrocarbon resins) was used as a compatibilizer and bis(3-triethoxysilylpropyl)tetrasulfide (TESPT) was used as a coupling agent. The vulcanizate properties and the morphological studies revealed that EPDM and SBR were incompatible, and the addition of AAHR was very effective to enhance the compatibility between EPDM and SBR. The weight percent of bound rubbers was increased with increasing SBR contents. The addition of an AAHR increased the amounts of bound rubbers, and hence the vulcanizate properties such as tear strength and fatigue resistance of the EPDM/SBR blends were improved. The dynamic mechanical analysis and the morphological studies revealed that the addition of TESPT increased the weight of bound rubbers and provided better dispersion of carbon black, resulting in good mechanical properties such as tear strength and fatigue resistance of the vulcanized EPDM/SBR blends. The smaller particle of zinc oxide (i.e., 50 nm > 100 nm > 1000 nm) yielded to the better blending properties of the polymer blend.

Paleogenetic analyses reveal unsuspected phylogenetic affinities between mice and the extinct Malpaisomys insularis, an endemic rodent of the Canaries.

PubMed

Pagès, Marie; Chevret, Pascale; Gros-Balthazard, Muriel; Hughes, Sandrine; Alcover, Josep Antoni; Hutterer, Rainer; Rando, Juan Carlos; Michaux, Jacques; Hänni, Catherine

2012-01-01

The lava mouse, Malpaisomys insularis, was endemic to the Eastern Canary islands and became extinct at the beginning of the 14(th) century when the Europeans reached the archipelago. Studies to determine Malpaisomys' phylogenetic affinities, based on morphological characters, remained inconclusive because morphological changes experienced by this insular rodent make phylogenetic investigations a real challenge. Over 20 years since its first description, Malpaisomys' phylogenetic position remains enigmatic. In this study, we resolved this issue using molecular characters. Mitochondrial and nuclear markers were successfully amplified from subfossils of three lava mouse samples. Molecular phylogenetic reconstructions revealed, without any ambiguity, unsuspected relationships between Malpaisomys and extant mice (genus Mus, Murinae). Moreover, through molecular dating we estimated the origin of the Malpaisomys/mouse clade at 6.9 Ma, corresponding to the maximal age at which the archipelago was colonised by the Malpaisomys ancestor via natural rafting. This study reconsiders the derived morphological characters of Malpaisomys in light of this unexpected molecular finding. To reconcile molecular and morphological data, we propose to consider Malpaisomys insularis as an insular lineage of mouse.

Growth of high-quality AlN epitaxial film by optimizing the Si substrate surface

NASA Astrophysics Data System (ADS)

Huang, Liegen; Li, Yuan; Wang, Wenliang; Li, Xiaochan; zheng, Yulin; Wang, Haiyan; Zhang, Zichen; Li, Guoqiang

2018-03-01

High-quality AlN epitaxial films have been grown on Si substrates by optimizing the hydrofluoric acid (HF) solution for cleaning of Si substrates. Effect of the Si substrate surface on the surface morphology and structural property of AlN epitaxial films is investigated in detail. It is revealed that as the concentration of HF solution increases from 0 to 2.0%, the surface morphology and the crystalline quality are initially improved and then get worse, and show an optimized value at 1.5%. The as-grown ∼200 nm-thick AlN epitaxial films on Si substrates grown with HF solution of 1.5% reveal the root-mean-square (RMS) surface roughness of 0.49 nm and the full-width at half-maximum for AlN(0002) X-ray rocking curve of 0.35°, indicating the smooth surface morphology and the high crystalline quality. The corresponding mechanism is proposed to interpret the effect of Si substrate surface on surface morphology and structural property of AlN epitaxial films, and provides an effective approach for the perspective fabrication of AlN-based devices.

Interactive Effects of Nutrient and Mechanical Stresses on Plant Morphology

PubMed Central

Puijalon, Sara; Lena, Jean-Paul; Bornette, Gudrun

2007-01-01

Background and Aims Plant species frequently encounter multiple stresses under natural conditions, and the way they cope with these stresses is a major determinant of their ecological breadth. The way mechanical (e.g. wind, current) and resource stresses act simultaneously on plant morphological traits has been poorly addressed, even if both stresses often interact. This paper aims to assess whether hydraulic stress affects plant morphology in the same way at different nutrient levels. Methods An examination was made of morphological variations of an aquatic plant species growing under four hydraulic stress (flow velocity) gradients located in four habitats distributed along a nutrient gradient. Morphological traits covering plant size, dry mass allocation, organ water content and foliage architecture were measured. Key Results Significant interactive effects of flow velocity and nutrient level were observed for all morphological traits. In particular, increased flow velocity resulted in size reductions under low nutrient conditions, suggesting an adaptive response to flow stress (escape strategy). On the other hand, moderate increases in flow velocity resulted in increased size under high nutrient conditions, possibly related to an inevitable growth response to a higher nutrient supply induced by water renewal at the plant surface. For some traits (e.g. dry mass allocation), a consistent sense of variation as a result of increasing flow velocity was observed, but the amount of variation was either reduced or amplified under nutrient-rich compared with nutrient-poor conditions, depending on the traits considered. Conclusions These results suggest that, for a given species, a stress factor may result, in contrasting patterns and hence strategies, depending on a second stress factor. Such results emphasize the relevance of studies on plant responses to multiple stresses for understanding the actual ecological breadth of species. PMID:17913725

Sperm motility and morphology changes in rats exposed to cadmium and diazinon.

PubMed

Adamkovicova, Maria; Toman, Robert; Martiniakova, Monika; Omelka, Radoslav; Babosova, Ramona; Krajcovicova, Vladimira; Grosskopf, Birgit; Massanyi, Peter

2016-08-08

Humans are ubiquitously exposed to multiple environmental contaminants. Consequences of combined action on the reproductive system remain unknown. This study aimed to assess single and joint effects of cadmium and diazinon exposure on sperm quality parameters. Male adult Wistar rats were randomized into 4 groups of ten animals each. Group A was used as a control, animals from group B were exposed to cadmium (30 mg/L), rats from group C were administered with diazinon (40 mg/L), and rats from group D were exposed simultaneously to cadmium (30 mg/L) and diazinon (40 mg/L) via drinking water for 90 days. Sperm morphology and motility were evaluated using a bright field microscope and a computer-assisted semen analysis. The percentage of motile spermatozoa and morphologically normal sperm was markedly reduced in rats from the group B. Rats from the C group showed an increase in velocity parameters, amplitude of lateral head displacement, decrease in beat-cross frequency, and an increase in abnormal sperm morphology. Simultaneous coexposure to cadmium and diazinon increased distance and velocity parameters, and amplitude of lateral head displacement. Reductions were observed in straightness, linearity, wobble, and beat-cross frequency. The decreased normal sperm morphology rates were related to defects of the sperm tail. Exposure to cadmium and diazinon at relatively low doses impairs sperm quality and can reduce male fertility. Cadmium and diazinon caused significant changes on sperm morphology with varying effects on motility patterns. These parameters were significantly higher in the group D as compared to the group C. The findings have important implications for reproductive risk assessment of combined exposures to multiple chemicals.

Four reversible and reconfigurable structures for three-phase emulsions: extended morphologies and applications

NASA Astrophysics Data System (ADS)

Ge, Xue-Hui; Geng, Yu-Hao; Zhang, Qiao-Chu; Shao, Meng; Chen, Jian; Luo, Guang-Sheng; Xu, Jian-Hong

2017-02-01

Here in this article, we classify and conclude the four morphologies of three-phase emulsions. Remarkably, we achieve the reversible transformations between every shape. Through theoretical analysis, we choose four liquid systems to form these four morphologies. Then monodispersed droplets with these four morphologies are formed through a microfluidic device and captured in a petri-dish. By replacing their ambient solution of the captured emulsions, in-situ morphology transformations between each shape are achieved. The process is well recorded through photographs and videos and they are systematical and reversible. Finally, we use the droplets structure to form an on-off switch to start and shut off the evaporation of one volatile phase to achieve the process monitoring. This could be used to initiate and quench a reaction, which offers a novel idea to achieve the switchable and reversible reaction control in multiple-phase reactions.

Morphological divergence in a continental adaptive radiation: South American ovenbirds of the genus Cinclodes

USGS Publications Warehouse

Rader, Jonathan A.; Dillon, Michael E.; Chesser, R. Terry; Sabat, Pablo; Martinez del Rio, Carlos

2015-01-01

Cinclodes is an ecologically diverse genus of South American passerine birds and represents a case of continental adaptive radiation along multiple axes. We investigated morphological diversification in Cinclodes using a comprehensive set of morphometric measurements of study skins. Principal component analysis identified 2 primary axes of morphological variation: one describing body size and a second capturing differences in wing-tip shape and toe length. Phylogenetic analyses of the first principal component suggest an early divergence ofCinclodes into 2 main clades characterized by large and small body sizes. We suggest that 2 morphological outliers within these main clades (C. antarcticus and C. palliatus) may be cases of island gigantism and that a third (C. patagonicus) may reflect ecological character displacement. Despite its ecological and physiological diversity, the genus Cinclodes does not appear to show morphological diversity beyond what is typical of other avian genera.

Multilocus phylogeny of the avian family Alaudidae (larks) reveals complex morphological evolution, non-monophyletic genera and hidden species diversity.

PubMed

Alström, Per; Barnes, Keith N; Olsson, Urban; Barker, F Keith; Bloomer, Paulette; Khan, Aleem Ahmed; Qureshi, Masood Ahmed; Guillaumet, Alban; Crochet, Pierre-André; Ryan, Peter G

2013-12-01

The Alaudidae (larks) is a large family of songbirds in the superfamily Sylvioidea. Larks are cosmopolitan, although species-level diversity is by far largest in Africa, followed by Eurasia, whereas Australasia and the New World have only one species each. The present study is the first comprehensive phylogeny of the Alaudidae. It includes 83.5% of all species and representatives from all recognised genera, and was based on two mitochondrial and three nuclear loci (in total 6.4 kbp, although not all loci were available for all species). In addition, a larger sample, comprising several subspecies of some polytypic species was analysed for one of the mitochondrial loci. There was generally good agreement in trees inferred from different loci, although some strongly supported incongruences were noted. The tree based on the concatenated multilocus data was overall well resolved and well supported by the data. We stress the importance of performing single gene as well as combined data analyses, as the latter may obscure significant incongruence behind strong nodal support values. The multilocus tree revealed many unpredicted relationships, including some non-monophyletic genera (Calandrella, Mirafra, Melanocorypha, Spizocorys). The tree based on the extended mitochondrial data set revealed several unexpected deep divergences between taxa presently treated as conspecific (e.g. within Ammomanes cinctura, Ammomanes deserti, Calandrella brachydactyla, Eremophila alpestris), as well as some shallow splits between currently recognised species (e.g. Certhilauda brevirostris-C. semitorquata-C. curvirostris; Calendulauda barlowi-C. erythrochlamys; Mirafra cantillans-M. javanica). Based on our results, we propose a revised generic classification, and comment on some species limits. We also comment on the extraordinary morphological adaptability in larks, which has resulted in numerous examples of parallel evolution (e.g. in Melanocorypha mongolica and Alauda leucoptera [both usually placed in Melanocorypha]; Ammomanopsis grayi and Ammomanes cinctura/deserti [former traditionally placed in Ammomanes]; Chersophilus duponti and Certhilauda spp.; Eremopterix hova [usually placed in Mirafra] and several Mirafra spp.), as well as both highly conserved plumages (e.g. within Mirafra) and strongly divergent lineages (e.g. Eremopterix hova vs. other Eremopterix spp.; Calandrella cinerea complex vs. Eremophila spp.; Eremalauda dunni vs. Chersophilus duponti; Melanocorypha mongolica and male M. yeltoniensis vs. other Melanocorypha spp. and female M. yeltoniensis). Sexual plumage dimorphism has evolved multiple times. Few groups of birds show the same level of disagreement between taxonomy based on morphology and phylogenetic relationships as inferred from DNA sequences. Copyright © 2013 Elsevier Inc. All rights reserved.

Determinants and taxonomic consequences of extreme egg shell variability in Ramazzottius subanomalus (Biserov, 1985) (Tardigrada).

PubMed

Stec, Daniel; Morek, Witold; Gąsiorek, Piotr; Kaczmarek, Łukasz; Michalczyk, Łukasz

2016-12-15

Nearly a half of known eutardigrade species lay ornamented eggs. The ornamentation is thought to provide attachment of the egg to the substrate and protection for the developing embryo, but from the taxonomic point of view chorion morphology may also provide key characters for species differentiation and identification, especially between closely related taxa. Nonetheless, despite the evolutionary and taxonomic importance of the egg shell, the determinants of its morphology are very poorly, if at all, understood. Here, we combine morphological, molecular and experimental approaches in an attempt to separate the genetic and environmental factors that shape egg chorion morphology in Ramazzottius subanomalus (Biserov, 1985). Our integrative study, based on a population of R. subanomalus isolated from a single moss sample, revealed (1) remarkable variation in egg shell morphology, but (2) relatively little variation in animal morphometric traits, and (3) genetic differentiation, expressed as two ITS-2 haplotypes, but no parallel polymorphism in COI. Although animals did not differ morphometrically between the haplotypes, eggs laid by haplotype 1 and 2 females exhibited highly statistically significant differences in all measured traits. The study demonstrates, for the first time, a correlation between phenotypic and genetic variability within a tardigrade species. The revealed congruence between genetic and morphological traits might be viewed as an example of incipient speciation that illustrates early evolutionary steps leading to species complexes that differ primarily in terms of egg shell morphology. Moreover, our data confirm the value of the ITS-2 fragment in distinguishing very closely related tardigrade lineages.

Integrated Metabolomics and Morphogenesis Reveal Volatile Signaling of the Nematode-Trapping Fungus Arthrobotrys oligospora.

PubMed

Wang, Bai-Le; Chen, Yong-Hong; He, Jia-Ning; Xue, Hua-Xi; Yan, Ni; Zeng, Zhi-Jun; Bennett, Joan W; Zhang, Ke-Qin; Niu, Xue-Mei

2018-05-01

The adjustment of metabolic patterns is fundamental to fungal biology and plays vital roles in adaptation to diverse ecological challenges. Nematode-trapping fungi can switch their lifestyle from saprophytic to pathogenic by developing specific trapping devices induced by nematodes to infect their prey as a response to nutrient depletion in nature. However, the chemical identity of the specific fungal metabolites used during the switch remains poorly understood. We hypothesized that these important signal molecules might be volatile in nature. Gas chromatography-mass spectrometry was used to carry out comparative analysis of fungal metabolomics during the saprophytic and pathogenic lifestyles of the model species Arthrobotrys oligospora Two media commonly used in research on this species, cornmeal agar (CMA) and potato dextrose agar (PDA), were chosen for use in this study. The fungus produced a small group of volatile furanone and pyrone metabolites that were associated with the switch from the saprophytic to the pathogenic stage. A. oligospora fungi grown on CMA tended to produce more traps and employ attractive furanones to improve the utilization of traps, while fungi grown on PDA developed fewer traps and used nematode-toxic furanone metabolites to compensate for insufficient traps. Another volatile pyrone metabolite, maltol, was identified as a morphological regulator for enhancing trap formation. Deletion of the gene AOL_s00079g496 in A. oligospora led to increased amounts of the furanone attractant (2-fold) in mutants and enhanced the attractive activity (1.5-fold) of the fungus, while it resulted in decreased trap formation. This investigation provides new insights regarding the comprehensive tactics of fungal adaptation to environmental stress, integrating both morphological and metabolomic mechanisms. IMPORTANCE Nematode-trapping fungi are a unique group of soil-living fungi that can switch from the saprophytic to the pathogenic lifestyle once they come into contact with nematodes as a response to nutrient depletion. In this study, we investigated the metabolic response during the switch and the key types of metabolites involved in the interaction between fungi and nematodes. Our findings indicate that A. oligospora develops multiple and flexible metabolic tactics corresponding to different morphological responses to nematodes. A. oligospora can use similar volatile furanone and pyrone metabolites with different ecological functions to help capture nematodes in the fungal switch from the saprophytic to the pathogenic lifestyle. Furthermore, studies with A. oligospora mutants with increased furanone and pyrone metabolites confirmed the results. This investigation reveals the importance of volatile signaling in the comprehensive tactics used by nematode-trapping fungi, integrating both morphological and metabolomic mechanisms. Copyright © 2018 Wang et al.

Integrated Metabolomics and Morphogenesis Reveal Volatile Signaling of the Nematode-Trapping Fungus Arthrobotrys oligospora

PubMed Central

Wang, Bai-Le; Chen, Yong-Hong; He, Jia-Ning; Xue, Hua-Xi; Yan, Ni; Zeng, Zhi-Jun; Bennett, Joan W.

2018-01-01

ABSTRACT The adjustment of metabolic patterns is fundamental to fungal biology and plays vital roles in adaptation to diverse ecological challenges. Nematode-trapping fungi can switch their lifestyle from saprophytic to pathogenic by developing specific trapping devices induced by nematodes to infect their prey as a response to nutrient depletion in nature. However, the chemical identity of the specific fungal metabolites used during the switch remains poorly understood. We hypothesized that these important signal molecules might be volatile in nature. Gas chromatography-mass spectrometry was used to carry out comparative analysis of fungal metabolomics during the saprophytic and pathogenic lifestyles of the model species Arthrobotrys oligospora. Two media commonly used in research on this species, cornmeal agar (CMA) and potato dextrose agar (PDA), were chosen for use in this study. The fungus produced a small group of volatile furanone and pyrone metabolites that were associated with the switch from the saprophytic to the pathogenic stage. A. oligospora fungi grown on CMA tended to produce more traps and employ attractive furanones to improve the utilization of traps, while fungi grown on PDA developed fewer traps and used nematode-toxic furanone metabolites to compensate for insufficient traps. Another volatile pyrone metabolite, maltol, was identified as a morphological regulator for enhancing trap formation. Deletion of the gene AOL_s00079g496 in A. oligospora led to increased amounts of the furanone attractant (2-fold) in mutants and enhanced the attractive activity (1.5-fold) of the fungus, while it resulted in decreased trap formation. This investigation provides new insights regarding the comprehensive tactics of fungal adaptation to environmental stress, integrating both morphological and metabolomic mechanisms. IMPORTANCE Nematode-trapping fungi are a unique group of soil-living fungi that can switch from the saprophytic to the pathogenic lifestyle once they come into contact with nematodes as a response to nutrient depletion. In this study, we investigated the metabolic response during the switch and the key types of metabolites involved in the interaction between fungi and nematodes. Our findings indicate that A. oligospora develops multiple and flexible metabolic tactics corresponding to different morphological responses to nematodes. A. oligospora can use similar volatile furanone and pyrone metabolites with different ecological functions to help capture nematodes in the fungal switch from the saprophytic to the pathogenic lifestyle. Furthermore, studies with A. oligospora mutants with increased furanone and pyrone metabolites confirmed the results. This investigation reveals the importance of volatile signaling in the comprehensive tactics used by nematode-trapping fungi, integrating both morphological and metabolomic mechanisms. PMID:29453265

The effects of tissue-non-specific alkaline phosphatase gene therapy on craniosynostosis and craniofacial morphology in the FGFR2C342Y/+ mouse model of Crouzon craniosynostosis.

PubMed

Wang, E; Nam, H K; Liu, J; Hatch, N E

2015-04-01

Craniosynostosis, the premature fusion of cranial bones, has traditionally been described as a disease of increased bone mineralization. However, multiple mouse models of craniosynostosis display craniosynostosis simultaneously with diminished cranial bone volume and/or density. We propose an alternative hypothesis that craniosynostosis results from abnormal tissue mineralization through the downregulation of tissue-non-specific alkaline phosphatase (TNAP) enzyme downstream of activating mutations in FGFRs. Neonatal Crouzon (FGFRC342Y/+) and wild-type (FGFR+/+) mice were injected with lentivirus to deliver a recombinant form of TNAP. Mice were sacrificed at 4 weeks postnatal. Serum was collected to test for alkaline phosphatase (AP), phosphorus, and calcium levels. Craniofacial bone fusion and morphology were assessed by micro-computed tomography. Injection with the TNAP lentivirus significantly increased serum AP levels (increased serum AP levels are indicative of efficient transduction and production of the recombinant protein), but results were variable and dependent upon viral lot and the litter of mice injected. Morphological analysis revealed craniofacial form differences for inferior surface (p=0.023) and cranial height (p=0.014) regions between TNAP lentivirus-injected and vehicle-injected Crouzon mice. With each unit increase in AP level, the odds of lambdoid suture fusion decreased by 84.2% and these results came close to statistical significance (p=0.068). These results suggest that TNAP deficiency may mediate FGFR2-associated craniosynostosis. Future studies should incorporate injection of recombinant TNAP protein, to avoid potential side effects and variable efficacy of lentiviral gene delivery. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Plasticity first: molecular signatures of a complex morphological trait in filamentous cyanobacteria.

PubMed

Koch, Robin; Kupczok, Anne; Stucken, Karina; Ilhan, Judith; Hammerschmidt, Katrin; Dagan, Tal

2017-08-31

Filamentous cyanobacteria that differentiate multiple cell types are considered the peak of prokaryotic complexity and their evolution has been studied in the context of multicellularity origins. Species that form true-branching filaments exemplify the most complex cyanobacteria. However, the mechanisms underlying the true-branching morphology remain poorly understood despite of several investigations that focused on the identification of novel genes or pathways. An alternative route for the evolution of novel traits is based on existing phenotypic plasticity. According to that scenario - termed genetic assimilation - the fixation of a novel phenotype precedes the fixation of the genotype. Here we show that the evolution of transcriptional regulatory elements constitutes a major mechanism for the evolution of new traits. We found that supplementation with sucrose reconstitutes the ancestral branchless phenotype of two true-branching Fischerella species and compared the transcription start sites (TSSs) between the two phenotypic states. Our analysis uncovers several orthologous TSSs whose transcription level is correlated with the true-branching phenotype. These TSSs are found in genes that encode components of the septosome and elongasome (e.g., fraC and mreB). The concept of genetic assimilation supplies a tenable explanation for the evolution of novel traits but testing its feasibility is hindered by the inability to recreate and study the evolution of present-day traits. We present a novel approach to examine transcription data for the plasticity first route and provide evidence for its occurrence during the evolution of complex colony morphology in true-branching cyanobacteria. Our results reveal a route for evolution of the true-branching phenotype in cyanobacteria via modification of the transcription level of pre-existing genes. Our study supplies evidence for the 'plasticity-first' hypothesis and highlights the importance of transcriptional regulation in the evolution of novel traits.

Effects of pH values of hydrogen peroxide bleaching agents on enamel surface properties.

PubMed

Xu, B; Li, Q; Wang, Y

2011-01-01

This study investigated the influence of pH values of bleaching agents on the properties of the enamel surface. Sixty freshly extracted premolars were embedded in epoxy resin and mesiodistally sectioned through the buccal aspect into two parts. The sectioned slabs were distributed among six groups (n=10) and treated using different solutions. Group HCl was treated with HCl solution (pH=3.0) and served as a positive control. Group DW, stored in distilled water (pH=7.0), served as a negative control. Four treatment groups were treated using 30% hydrogen peroxide solutions with different pH values: group HP3 (pH=3.0), group HP5 (pH=5.0), group HP7 (pH=7.0), and group HP8 (pH=8.0). The buccal slabs were subjected to spectrophotometric evaluations. Scanning electron microscopy investigation and Micro-Raman spectroscopy were used to evaluate enamel surface morphological and chemical composition alterations. pH value has a significant influence on the color changes after bleaching (p<0.001). Tukey's multiple comparisons revealed that the order of color changes was HP8, HP7>HP5, HP3>HCl>DW. No obvious morphological alterations were detected on the enamel surface in groups DW, HP7, and HP8. The enamel surface of groups HCl and HP3 showed significant alterations with an erosion appearance. No obvious chemical composition changes were detected with respect to Micro-Raman analysis. Within the limitations of this study, it was concluded that no obvious morphological or chemical composition alterations of enamel surface were detected in the neutral or alkaline bleaching solutions. Bleaching solutions with lower pH values could result in more significant erosion of enamel, which represented a slight whitening effect.

Petascale Simulations of the Morphology and the Molecular Interface of Bulk Heterojunctions

DOE PAGES

Carrillo, Jan-Michael Y.; Seibers, Zach; Kumar, Rajeev; ...

2016-07-14

Understanding how additives interact and segregate within bulk heterojunction (BHJ) thin films is critical for exercising control over structure at multiple length scales and delivering improvements in photovoltaic performance. The morphological evolution of poly(3-hexylthiophene) (P3HT) and phenyl-C 61-butyric acid methyl ester (PCBM) blends that are commensurate with the size of a BHJ thin film is examined using petascale coarse-grained molecular dynamics simulations. When comparing 2 component and 3 component systems containing short P3HT chains as additives undergoing thermal annealing we demonstrate that the short chains alter the morphol- ogy in apparently useful ways: They efficiently migrate to the P3HT/PCBM interface,more » increasing the P3HT domain size and interfacial area. Simulation results agree with depth profiles determined from neutron reflectometry measurements that reveal PCBM enrichment near substrate and air interfaces, but a decrease in that PCBM enrich- ment when a small amount of short P3HT chains are integrated into the BHJ blend. Atomistic simulations of the P3HT/PCBM blend interfaces show a non-monotonic dependence of the interfacial thickness as a function of number of repeat units in the oligomeric P3HT additive, and the thiophene rings orient parallel to the interfacial plane as they approach the PCBM domain. Using the nanoscale geometries of the P3HT oligomers, LUMO and HOMO energy levels calculated by density functional theory are found to be invariant across the donor/acceptor interface. Finally, these connections between additives, processing, and morphology at all length scales are generally useful for efforts to improve device performance.« less

Developmental morphology of cover crop species exhibit contrasting behaviour to changes in soil bulk density, revealed by X-ray computed tomography

PubMed Central

Burr-Hersey, Jasmine E.; Mooney, Sacha J.; Bengough, A. Glyn; Mairhofer, Stefan

2017-01-01

Plant roots growing through soil typically encounter considerable structural heterogeneity, and local variations in soil dry bulk density. The way the in situ architecture of root systems of different species respond to such heterogeneity is poorly understood due to challenges in visualising roots growing in soil. The objective of this study was to visualise and quantify the impact of abrupt changes in soil bulk density on the roots of three cover crop species with contrasting inherent root morphologies, viz. tillage radish (Raphanus sativus), vetch (Vicia sativa) and black oat (Avena strigosa). The species were grown in soil columns containing a two-layer compaction treatment featuring a 1.2 g cm-3 (uncompacted) zone overlaying a 1.4 g cm-3 (compacted) zone. Three-dimensional visualisations of the root architecture were generated via X-ray computed tomography, and an automated root-segmentation imaging algorithm. Three classes of behaviour were manifest as a result of roots encountering the compacted interface, directly related to the species. For radish, there was switch from a single tap-root to multiple perpendicular roots which penetrated the compacted zone, whilst for vetch primary roots were diverted more horizontally with limited lateral growth at less acute angles. Black oat roots penetrated the compacted zone with no apparent deviation. Smaller root volume, surface area and lateral growth were consistently observed in the compacted zone in comparison to the uncompacted zone across all species. The rapid transition in soil bulk density had a large effect on root morphology that differed greatly between species, with major implications for how these cover crops will modify and interact with soil structure. PMID:28753645

Developmental morphology of cover crop species exhibit contrasting behaviour to changes in soil bulk density, revealed by X-ray computed tomography.

PubMed

Burr-Hersey, Jasmine E; Mooney, Sacha J; Bengough, A Glyn; Mairhofer, Stefan; Ritz, Karl

2017-01-01

Plant roots growing through soil typically encounter considerable structural heterogeneity, and local variations in soil dry bulk density. The way the in situ architecture of root systems of different species respond to such heterogeneity is poorly understood due to challenges in visualising roots growing in soil. The objective of this study was to visualise and quantify the impact of abrupt changes in soil bulk density on the roots of three cover crop species with contrasting inherent root morphologies, viz. tillage radish (Raphanus sativus), vetch (Vicia sativa) and black oat (Avena strigosa). The species were grown in soil columns containing a two-layer compaction treatment featuring a 1.2 g cm-3 (uncompacted) zone overlaying a 1.4 g cm-3 (compacted) zone. Three-dimensional visualisations of the root architecture were generated via X-ray computed tomography, and an automated root-segmentation imaging algorithm. Three classes of behaviour were manifest as a result of roots encountering the compacted interface, directly related to the species. For radish, there was switch from a single tap-root to multiple perpendicular roots which penetrated the compacted zone, whilst for vetch primary roots were diverted more horizontally with limited lateral growth at less acute angles. Black oat roots penetrated the compacted zone with no apparent deviation. Smaller root volume, surface area and lateral growth were consistently observed in the compacted zone in comparison to the uncompacted zone across all species. The rapid transition in soil bulk density had a large effect on root morphology that differed greatly between species, with major implications for how these cover crops will modify and interact with soil structure.

Phylogenetic analysis of molecular and morphological data highlights uncertainty in the relationships of fossil and living species of Elopomorpha (Actinopterygii: Teleostei).

PubMed

Dornburg, Alex; Friedman, Matt; Near, Thomas J

2015-08-01

Elopomorpha is one of the three main clades of living teleost fishes and includes a range of disparate lineages including eels, tarpons, bonefishes, and halosaurs. Elopomorphs were among the first groups of fishes investigated using Hennigian phylogenetic methods and continue to be the object of intense phylogenetic scrutiny due to their economic significance, diversity, and crucial evolutionary status as the sister group of all other teleosts. While portions of the phylogenetic backbone for Elopomorpha are consistent between studies, the relationships among Albula, Pterothrissus, Notacanthiformes, and Anguilliformes remain contentious and difficult to evaluate. This lack of phylogenetic resolution is problematic as fossil lineages are often described and placed taxonomically based on an assumed sister group relationship between Albula and Pterothrissus. In addition, phylogenetic studies using morphological data that sample elopomorph fossil lineages often do not include notacanthiform or anguilliform lineages, potentially introducing a bias toward interpreting fossils as members of the common stem of Pterothrissus and Albula. Here we provide a phylogenetic analysis of DNA sequences sampled from multiple nuclear genes that include representative taxa from Albula, Pterothrissus, Notacanthiformes and Anguilliformes. We integrate our molecular dataset with a morphological character matrix that spans both living and fossil elopomorph lineages. Our results reveal substantial uncertainty in the placement of Pterothrissus as well as all sampled fossil lineages, questioning the stability of the taxonomy of fossil Elopomorpha. However, despite topological uncertainty, our integration of fossil lineages into a Bayesian time calibrated framework provides divergence time estimates for the clade that are consistent with previously published age estimates based on the elopomorph fossil record and molecular estimates resulting from traditional node-dating methods. Copyright © 2015 Elsevier Inc. All rights reserved.

Hox gene expression during postlarval development of the polychaete Alitta virens.

PubMed

Bakalenko, Nadezhda I; Novikova, Elena L; Nesterenko, Alexander Y; Kulakova, Milana A

2013-05-01

Hox genes are the family of transcription factors that play a key role in the patterning of the anterior-posterior axis of all bilaterian animals. These genes display clustered organization and colinear expression. Expression boundaries of individual Hox genes usually correspond with morphological boundaries of the body. Previously, we studied Hox gene expression during larval development of the polychaete Alitta virens (formerly Nereis virens) and discovered that Hox genes are expressed in nereid larva according to the spatial colinearity principle. Adult Alitta virens consist of multiple morphologically similar segments, which are formed sequentially in the growth zone. Since the worm grows for most of its life, postlarval segments constantly change their position along the anterior-posterior axis. We studied the expression dynamics of the Hox cluster during postlarval development of the nereid Alitta virens and found that 8 out of 11 Hox genes are transcribed as wide gene-specific gradients in the ventral nerve cord, ectoderm, and mesoderm. The expression domains constantly shift in accordance with the changing proportions of the growing worm, so expression domains of most Hox genes do not have stable anterior or/and posterior boundaries.In the course of our study, we revealed long antisense RNA (asRNA) for some Hox genes. Expression patterns of two of these genes were analyzed using whole-mount in-situ hybridization. This is the first discovery of antisense RNA for Hox genes in Lophotrochozoa. Hox gene expression in juvenile A. virens differs significantly from Hox gene expression patterns both in A. virens larva and in other Bilateria.We suppose that the postlarval function of the Hox genes in this polychaete is to establish and maintain positional coordinates in a constantly growing body, as opposed to creating morphological difference between segments.

DNA barcoding and morphological identification of neotropical ichthyoplankton from the Upper Paraná and São Francisco.

PubMed

Becker, R A; Sales, N G; Santos, G M; Santos, G B; Carvalho, D C

2015-07-01

The identification of fish larvae from two neotropical hydrographic basins using traditional morphological taxonomy and DNA barcoding revealed no conflicting results between the morphological and barcode identification of larvae. A lower rate (25%) of correct morphological identification of eggs as belonging to migratory or non-migratory species was achieved. Accurate identification of ichthyoplankton by DNA barcoding is an important tool for fish reproductive behaviour studies, correct estimation of biodiversity by detecting eggs from rare species, as well as defining environmental and management strategies for fish conservation in the neotropics. © 2015 The Fisheries Society of the British Isles.

Arsenic distribution and valence state variation studied by fast hierarchical length-scale morphological, compositional, and speciation imaging at the Nanoscopium, Synchrotron Soleil

NASA Astrophysics Data System (ADS)

Somogyi, Andrea; Medjoubi, Kadda; Sancho-Tomas, Maria; Visscher, P. T.; Baranton, Gil; Philippot, Pascal

2017-09-01

The understanding of real complex geological, environmental and geo-biological processes depends increasingly on in-depth non-invasive study of chemical composition and morphology. In this paper we used scanning hard X-ray nanoprobe techniques in order to study the elemental composition, morphology and As speciation in complex highly heterogeneous geological samples. Multivariate statistical analytical techniques, such as principal component analysis and clustering were used for data interpretation. These measurements revealed the quantitative and valance state inhomogeneity of As and its relation to the total compositional and morphological variation of the sample at sub-μm scales.

Semantic processing during morphological priming: an ERP study.

PubMed

Beyersmann, Elisabeth; Iakimova, Galina; Ziegler, Johannes C; Colé, Pascale

2014-09-04

Previous research has yielded conflicting results regarding the onset of semantic processing during morphological priming. The present study was designed to further explore the time-course of morphological processing using event-related potentials (ERPs). We conducted a primed lexical decision study comparing a morphological (LAVAGE - laver [washing - wash]), a semantic (LINGE - laver [laundry - wash]), an orthographic (LAVANDE - laver [lavender - wash]), and an unrelated control condition (HOSPICE - laver [nursing home - wash]), using the same targets across the four priming conditions. The behavioral data showed significant effects of morphological and semantic priming, with the magnitude of morphological priming being significantly larger than the magnitude of semantic priming. The ERP data revealed significant morphological but no semantic priming at 100-250 ms. Furthermore, a reduction of the N400 amplitude in the morphological condition compared to the semantic and orthographic condition demonstrates that the morphological priming effect was not entirely due to the semantic or orthographic overlap between the prime and the target. The present data reflect an early process of semantically blind morphological decomposition, and a later process of morpho-semantic decomposition, which we discuss in the context of recent morphological processing theories. Copyright © 2014 Elsevier B.V. All rights reserved.

The Arabidopsis USL1 controls multiple aspects of development by affecting late endosome morphology.

PubMed

Yuan, Rongrong; Lan, Jingqiu; Fang, Yuxing; Yu, Hao; Zhang, Jinzhe; Huang, Jiaying; Qin, Genji

2018-06-13

The polar transport of auxin controls many aspects of plant development. However, the molecular mechanisms underlying auxin tranport regulation remain to be further elucidated. We identified a mutant named as usl1 (unflattened and small leaves) in a genetic screen in Arabidopsis thaliana. The usl1 displayed multiple aspects of developmental defects in leaves, embryogenesis, cotyledons, silique phyllotaxy and lateral roots in addition to abnormal leaves. USL1 encodes a protein orthologous to the yeast vacuolar protein sorting (Vps) 38p and human UV RADIATION RESISTANCE-ASSOCIATED GENE (UVRAG). Cell biology, Co-IP/MS and yeast two-hybrid were used to identify the function of USL1. USL1 colocalizes at the subcellular level with VPS29, a key factor of the retromer complex that controls auxin transport. The morphology of the VPS29-associated late endosomes (LE) is altered from small dots in the wild-type to aberrant enlarged circles in the usl1 mutants. The usl1 mutant synergistically interacts with vps29. We also found that USL1 forms a complex with AtVPS30 and AtVPS34. We propose that USL1 controls multiple aspects of plant development by affecting late endosome morphology and by regulating the PIN1 polarity. Our findings provide a new layer of the understanding on the mechanisms of plant development regulation. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

Niche segregation among sympatric Amazonian teiid lizards.

PubMed

Vitt, L J; Sartorius, S S; Avila-Pires, T C S; Espósito, M C; Miles, D B

2000-02-01

We examined standard niche axes (time, place, and food) for three sympatric teiid lizards in the Amazon rain forest. Activity times during the day were similar among species. Ameiva ameiva were in more open microhabitats and had higher body temperatures compared with the two species of Kentropyx. Microhabitat overlaps were low and not significantly different from simulations based on Monte Carlo analysis. Grasshoppers, crickets, and spiders were important in the diets of all three species and many relatively abundant prey were infrequently eaten (e.g., ants). Dietary overlaps were most similar between the two species of Kentropyx even though microhabitat overlaps were relatively low. A Monte Carlo analysis on prey types revealed that dietary overlaps were higher at all ranks than simulated overlaps indicating that use of prey is not random. Although prey size was correlated with lizard body size, there were no species differences in adjusted prey size. A. ameiva ate more prey items at a given body size than either species of Kentropyx. Body size varies among species, with A. ameiva being the largest and K. altamazonica the smallest. The two species of Kentropyx are most distant morphologically, with A. ameiva intermediate. The most distant species morphologically are the most similar in terms of prey types. A morphological analysis including 15 species from four genera revealed patterns of covariation that reflected phylogenetic affinities (i.e., taxonomic patterns are evident). A cluster analysis revealed that A. ameiva, K. pelviceps, and K. altamazonica were in the same morphological group and that within that group, A. ameiva differed from the rest of the species. In addition, K. pelviceps and K. altamazonica were distinguishable from other species of Kentropyx based on morphology.

The diversity and structure of marine protists in the coastal waters of China revealed by morphological observation and 454 pyrosequencing

NASA Astrophysics Data System (ADS)

Liu, Yun; Song, Shuqun; Chen, Tiantian; Li, Caiwen

2017-04-01

Pyrosequencing of the 18S rRNA gene has been widely adopted to study the eukaryotic diversity in various types of environments, and has an advantage over traditional morphology methods in exploring unknown microbial communities. To comprehensively assess the diversity and community composition of marine protists in the coastal waters of China, we applied both morphological observations and high-throughput sequencing of the V2 and V3 regions of 18S rDNA simultaneously to analyze samples collected from the surface layer of the Yellow and East China Seas. Dinoflagellates, diatoms and ciliates were the three dominant protistan groups as revealed by the two methods. Diatoms were the first dominant protistan group in the microscopic observations, with Skeletonema mainly distributed in the nearshore eutrophic waters and Chaetoceros in higher temperature and higher pH waters. The mixotrophic dinoflagellates, Gymnodinium and Gyrodinium, were more competitive in the oligotrophic waters. The pyrosequencing method revealed an extensive diversity of dinoflagellates. Chaetoceros was the only dominant diatom group in the pyrosequencing dataset. Gyrodinium represented the most abundant reads and dominated the offshore oligotrophic protistan community as they were in the microscopic observations. The dominance of parasitic dinoflagellates in the pyrosequencing dataset, which were overlooked in the morphological observations, indicates more attention should be paid to explore the potential role of this group. Both methods provide coherent clustering of samples. Nutrient levels, salinity and pH were the main factors influencing the distribution of protists. This study demonstrates that different primer pairs used in the pyrosequencing will indicate different protistan community structures. A suitable marker may reveal more comprehensive composition of protists and provide valuable information on environmental drivers.

Modelling rate distributions using character compatibility: implications for morphological evolution among fossil invertebrates

PubMed Central

Wagner, Peter J.

2012-01-01

Rate distributions are important considerations when testing hypotheses about morphological evolution or phylogeny. They also have implications about general processes underlying character evolution. Molecular systematists often assume that rates are Poisson processes with gamma distributions. However, morphological change is the product of multiple probabilistic processes and should theoretically be affected by hierarchical integration of characters. Both factors predict lognormal rate distributions. Here, a simple inverse modelling approach assesses the best single-rate, gamma and lognormal models given observed character compatibility for 115 invertebrate groups. Tests reject the single-rate model for nearly all cases. Moreover, the lognormal outperforms the gamma for character change rates and (especially) state derivation rates. The latter in particular is consistent with integration affecting morphological character evolution. PMID:21795266

Natural hybridization and genetic and morphological variation between two epiphytic bromeliads

PubMed Central

Neri, Jordana; Wendt, Tânia

2018-01-01

Abstract Reproductive isolation is of fundamental importance for maintaining species boundaries in sympatry. Here, we examine the genetic and morphological differences between two closely related bromeliad species: Vriesea simplex and Vriesea scalaris. Furthermore, we examined the occurrence of natural hybridization and discuss the action of reproductive isolation barriers. Nuclear genomic admixture suggests hybridization in sympatric populations, although interspecific gene flow is low among species in all sympatric zones (Nem < 0.5). Thus, morphological and genetic divergence (10.99 %) between species can be maintained despite ongoing natural hybridization. Cross-evaluation of our genetic and morphological data suggests that species integrity is maintained by the simultaneous action of multiple barriers, such as divergent reproductive systems among species, differences in floral traits and low hybrid seed viability. PMID:29308124

Wrinkling pattern evolution of cylindrical biological tissues with differential growth.

PubMed

Jia, Fei; Li, Bo; Cao, Yan-Ping; Xie, Wei-Hua; Feng, Xi-Qiao

2015-01-01

Three-dimensional surface wrinkling of soft cylindrical tissues induced by differential growth is explored. Differential volumetric growth can cause their morphological stability, leading to the formation of hexagonal and labyrinth wrinkles. During postbuckling, multiple bifurcations and morphological transitions may occur as a consequence of continuous growth in the surface layer. The physical mechanisms underpinning the morphological evolution are examined from the viewpoint of energy. Surface curvature is found to play a regulatory role in the pattern evolution. This study may not only help understand the morphogenesis of soft biological tissues, but also inspire novel routes for creating desired surface patterns of soft materials.

Cryptic diversity in a fig wasp community-morphologically differentiated species are sympatric but cryptic species are parapatric.

PubMed

Darwell, C T; Cook, J M

2017-02-01

A key debate in ecology centres on the relative importance of niche and neutral processes in determining patterns of community assembly with particular focus on whether ecologically similar species with similar functional traits are able to coexist. Meanwhile, molecular studies are increasingly revealing morphologically indistinguishable cryptic species with presumably similar ecological roles. Determining the geographic distribution of such cryptic species provides opportunities to contrast predictions of niche vs. neutral models. Discovery of sympatric cryptic species increases alpha diversity and supports neutral models, while documentation of allopatric/parapatric cryptic species increases beta diversity and supports niche models. We tested these predictions using morphological and molecular data, coupled with environmental niche modelling analyses, of a fig wasp community along its 2700-km latitudinal range. Molecular methods increased previous species diversity estimates from eight to eleven species, revealing morphologically cryptic species in each of the four wasp genera studied. Congeneric species pairs that were differentiated by a key morphological functional trait (ovipositor length) coexisted sympatrically over large areas. In contrast, morphologically similar species, with similar ovipositor lengths, typically showed parapatric ranges with very little overlap. Despite parapatric ranges, environmental niche models of cryptic congeneric pairs indicate large regions of potential sympatry, suggesting that competitive processes are important in determining the distributions of ecologically similar species. Niche processes appear to structure this insect community, and cryptic diversity may typically contribute mostly to beta rather than alpha diversity. © 2016 John Wiley & Sons Ltd.

Morphology enabled dipole inversion (MEDI) from a single-angle acquisition: comparison with COSMOS in human brain imaging.

PubMed

Liu, Tian; Liu, Jing; de Rochefort, Ludovic; Spincemaille, Pascal; Khalidov, Ildar; Ledoux, James Robert; Wang, Yi

2011-09-01

Magnetic susceptibility varies among brain structures and provides insights into the chemical and molecular composition of brain tissues. However, the determination of an arbitrary susceptibility distribution from the measured MR signal phase is a challenging, ill-conditioned inverse problem. Although a previous method named calculation of susceptibility through multiple orientation sampling (COSMOS) has solved this inverse problem both theoretically and experimentally using multiple angle acquisitions, it is often impractical to carry out on human subjects. Recently, the feasibility of calculating the brain susceptibility distribution from a single-angle acquisition was demonstrated using morphology enabled dipole inversion (MEDI). In this study, we further improved the original MEDI method by sparsifying the edges in the quantitative susceptibility map that do not have a corresponding edge in the magnitude image. Quantitative susceptibility maps generated by the improved MEDI were compared qualitatively and quantitatively with those generated by calculation of susceptibility through multiple orientation sampling. The results show a high degree of agreement between MEDI and calculation of susceptibility through multiple orientation sampling, and the practicality of MEDI allows many potential clinical applications. Copyright © 2011 Wiley-Liss, Inc.

Quantified biotic and abiotic responses to multiple stress in freshwater, marine and ground waters.

PubMed

Nõges, Peeter; Argillier, Christine; Borja, Ángel; Garmendia, Joxe Mikel; Hanganu, Jenică; Kodeš, Vit; Pletterbauer, Florian; Sagouis, Alban; Birk, Sebastian

2016-01-01

We reviewed 219 papers and built an inventory of 532 items of ecological evidence on multiple stressor impacts in rivers, lakes, transitional and coastal waters, as well as groundwaters. Our review revealed that, despite the existence of a huge conceptual knowledge base in aquatic ecology, few studies actually provide quantitative evidence on multi-stress effects. Nutrient stress was involved in 71% to 98% of multi-stress situations in the three types of surface water environments, and in 42% of those in groundwaters. However, their impact manifested differently along the groundwater-river-lake-transitional-coastal continuum, mainly determined by the different hydro-morphological features of these ecosystems. The reviewed papers addressed two-stressor combinations most frequently (42%), corresponding with the actual status-quo of pressures acting on European surface waters as reported by the Member States in the WISE WFD Database (EEA, 2015). Across all biological groups analysed, higher explanatory power of the stress-effect models was discernible for lakes under multi-stressor compared to single stressor conditions, but generally lower for coastal and transitional waters. Across all aquatic environments, the explanatory power of stress-effect models for fish increased when multi-stressor conditions were taken into account in the analysis, qualifying this organism group as a useful indicator of multi-stress effects. In contrast, the explanatory power of models using benthic flora decreased under conditions of multiple stress. Copyright © 2015 Elsevier B.V. All rights reserved.

Impact of stacking order on the microstructural properties of Cu2ZnGeSe4 thin film absorber layer

NASA Astrophysics Data System (ADS)

Mary, G. Swapna; Chandra, G. Hema; Sunil, M. Anantha; Subbaiah, Y. P. Venkata; Gupta, Mukul; Rao, R. Prasada

2018-05-01

Six possible multiple stacks of Cu-ZnSe-Ge with selenium incorporation at a precursor stage were prepared using electron beam evaporation followed by vacuum selenization at 475 °C for 30 min to investigate the role of stacking order on the growth and properties of Cu2ZnGeSe4 films. The X-ray diffraction measurements affirm the existence of various binary and ternary phases (ZnSe, Cu2Se, GeSe2 and Cu2GeSe3) for all the precursor stacks. These phases are completely diminished after selenization at 475 °C except a minor co-existence of ZnSe (111) phase along with dominant Cu2ZnGeSe4 (112) phase for stack A: (Cu/Se/ZnSe/Se/Ge/Se) × 4. The Raman measurements for selenized multiple stack A, revealed two major A3, A1 modes at 206 cm-1 and 176 cm-1 and one minor E5 mode at 270 cm-1 corresponding to CZGSe phase. The surface morphology and the elemental distribution across the thickness found to vary significantly with the change of stacking order. The selenized multiple stacks A films shows densely packed flake and capsule shaped grains. The selenized stack A found to have a direct energy band gap of 1.60 eV, showing p-type conductivity with a Hall mobility of 22 cm2 (Vs)-1.

Antibody-enhanced dengue disease generates a marked CNS inflammatory response in the black-tufted marmoset Callithrix penicillata.

PubMed

Vasconcelos, Barbara Cristina Baldez; Vieira, Juliana Almeida; Silva, Geane Oliveira; Fernandes, Taiany Nogueira; Rocha, Luciano Chaves; Viana, André Pereira; Serique, Cássio Diego Sá; Filho, Carlos Santos; Bringel, Raissa Aires Ribeiro; Teixeira, Francisco Fernando Dacier Lobato; Ferreira, Milene Silveira; Casseb, Samir Mansour Moraes; Carvalho, Valéria Lima; de Melo, Karla Fabiane Lopes; de Castro, Paulo Henrique Gomes; Araújo, Sanderson Corrêa; Diniz, José Antonio Picanço; Demachki, Samia; Anaissi, Ana Karyssa Mendes; Sosthenes, Marcia Consentino Kronka; Vasconcelos, Pedro Fernando da Costa; Anthony, Daniel Clive; Diniz, Cristovam Wanderley Picanço; Diniz, Daniel Guerreiro

2016-02-01

Severe dengue disease is often associated with long-term neurological impairments, but it is unclear what mechanisms are associated with neurological sequelae. Previously, we demonstrated antibody-enhanced dengue disease (ADE) dengue in an immunocompetent mouse model with a dengue virus 2 (DENV2) antibody injection followed by DENV3 virus infection. Here we migrated this ADE model to Callithrix penicillata. To mimic human multiple infections of endemic zones where abundant vectors and multiple serotypes co-exist, three animals received weekly subcutaneous injections of DENV3 (genotype III)-infected supernatant of C6/36 cell cultures, followed 24 h later by anti-DENV2 antibody for 12 weeks. There were six control animals, two of which received weekly anti-DENV2 antibodies, and four further animals received no injections. After multiple infections, brain, liver, and spleen samples were collected and tissue was immunolabeled for DENV3 antigens, ionized calcium binding adapter molecule 1, Ki-67, TNFα. There were marked morphological changes in the microglial population of ADE monkeys characterized by more highly ramified microglial processes, higher numbers of trees and larger surface areas. These changes were associated with intense TNFα-positive immunolabeling. It is unclear why ADE should generate such microglial activation given that IgG does not cross the blood-brain barrier, but this study reveals that in ADE dengue therapy targeting the CNS host response is likely to be important. © 2015 Japanese Society of Neuropathology.

Identification of Important Iranian Hardwoods by Morphological Properties of Vessel Elements (Maceration process)

Treesearch

Vahidreza Safdari; Margaret S. Devall

2011-01-01

For the identification of small to large wood samples and various types of composites that may not provide enough of all surfaces necessary to reveal diagnostic characteristics, such as sawdust, decayed wood fragments, archeological wood, and even large wood samples, morphological and anatomical characteristics of vessels are very useful. In this research,...

The relative effects on math performance of single- versus multiple-ratio schedules: a case study1

PubMed Central

Lovitt, Tom C.; Esveldt, Karen A.

1970-01-01

This series of four experiments sought to assess the comparative effects of multiple- versus single-ratio schedules on a pupil's responding to mathematics materials. Experiment I, which alternated between single- and multiple-ratio contingencies, revealed that during the latter phase the subject responded at a higher rate. Similar findings were revealed by Exp. II. The third experiment, which manipulated frequency of reinforcement rather than multiple ratios, revealed that the alteration had a minimal effect on the subject's response rate. A final experiment, conducted to assess further the effects of multiple ratios, provided data similar to those of Exp. I and II. PMID:16795267

Maternal creatine supplementation affects the morpho-functional development of hippocampal neurons in rat offspring.

PubMed

Sartini, S; Lattanzi, D; Ambrogini, P; Di Palma, M; Galati, C; Savelli, D; Polidori, E; Calcabrini, C; Rocchi, M B L; Sestili, P; Cuppini, R

2016-01-15

Creatine supplementation has been shown to protect neurons from oxidative damage due to its antioxidant and ergogenic functions. These features have led to the hypothesis of creatine supplementation use during pregnancy as prophylactic treatment to prevent CNS damage, such as hypoxic-ischemic encephalopathy. Unfortunately, very little is known on the effects of creatine supplementation during neuron differentiation, while in vitro studies revealed an influence on neuron excitability, leaving the possibility of creatine supplementation during the CNS development an open question. Using a multiple approach, we studied the hippocampal neuron morphological and functional development in neonatal rats born by dams supplemented with 1% creatine in drinking water during pregnancy. CA1 pyramidal neurons of supplemented newborn rats showed enhanced dendritic tree development, increased LTP maintenance, larger evoked-synaptic responses, and higher intrinsic excitability in comparison to controls. Moreover, a faster repolarizing phase of action potential with the appearance of a hyperpolarization were recorded in neurons of the creatine-treated group. Consistently, CA1 neurons of creatine exposed pups exhibited a higher maximum firing frequency than controls. In summary, we found that creatine supplementation during pregnancy positively affects morphological and electrophysiological development of CA1 neurons in offspring rats, increasing neuronal excitability. Altogether, these findings emphasize the need to evaluate the benefits and the safety of maternal intake of creatine in humans. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Exploring the Martian Highlands using a Rover-Deployed Ground Penetrating Radar

NASA Technical Reports Server (NTRS)

Grant, J. A.; Schutz, A. E.; Campbell, B. A.

2001-01-01

The Martian highlands record a long and often complex history of geologic activity that has shaped the planet over time. Results of geologic mapping and new data from the Mars Global Surveyor spacecraft reveal layered surfaces created by multiple processes that are often mantled by eolian deposits. Knowledge of the near-surface stratigraphy as it relates to evolution of surface morphology will provide critical context for interpreting rover/lander remote sensing data and for defining the geologic setting of a highland lander. Rover-deployed ground penetrating radar (GPR) can directly measure the range and character of in situ radar properties, thereby helping to constrain near-surface geology and structure. As is the case for most remote sensing instruments, a GPR may not detect water unambiguously on Mars. Nevertheless, any local, near-surface occurrence of liquid water will lead to large, easily detected dielectric contrasts. Moreover, definition of stratigraphy and setting will help in evaluating the history of aqueous activity and where any water might occur and be accessible. GPR data can also be used to infer the degree of any post-depositional pedogenic alteration or weathering, thereby enabling assessment of pristine versus secondary morphology. Most importantly perhaps, GPR can provide critical context for other rover and orbital instruments/data sets. Hence, rover-deployment of a GPR deployment should enable 3-D mapping of local stratigraphy and could guide subsurface sampling.

Discriminant analysis of multiple cortical changes in mild cognitive impairment

NASA Astrophysics Data System (ADS)

Wu, Congling; Guo, Shengwen; Lai, Chunren; Wu, Yupeng; Zhao, Di; Jiang, Xingjun

2017-02-01

To reveal the differences in brain structures and morphological changes between the mild cognitive impairment (MCI) and the normal control (NC), analyze and predict the risk of MCI conversion. First, the baseline and 2-year longitudinal follow-up magnetic resonance (MR) images of 73 NC, 46 patients with stable MCI (sMCI) and 40 patients with converted MCI (cMCI) were selected. Second, the FreeSurfer was used to extract the cortical features, including the cortical thickness, surface area, gray matter volume and mean curvature. Third, the support vector machine-recursive feature elimination method (SVM-RFE) were adopted to determine salient features for effective discrimination. Finally, the distribution and importance of essential brain regions were described. The experimental results showed that the cortical thickness and gray matter volume exhibited prominent capability in discrimination, and surface area and mean curvature behaved relatively weak. Furthermore, the combination of different morphological features, especially the baseline combined with the longitudinal changes, can be used to evidently improve the performance of classification. In addition, brain regions with high weights predominately located in the temporal lobe and the frontal lobe, which were relative to emotional control and memory functions. It suggests that there were significant different patterns in the brain structure and changes between the compared group, which could not only be effectively applied for classification, but also be used to evaluate and predict the conversion of the patients with MCI.

Novel NAC Transcription Factor TaNAC67 Confers Enhanced Multi-Abiotic Stress Tolerances in Arabidopsis

PubMed Central

Mao, Xinguo; Chen, Shuangshuang; Li, Ang; Zhai, Chaochao; Jing, Ruilian

2014-01-01

Abiotic stresses are major environmental factors that affect agricultural productivity worldwide. NAC transcription factors play pivotal roles in abiotic stress signaling in plants. As a staple crop, wheat production is severely constrained by abiotic stresses whereas only a few NAC transcription factors have been characterized functionally. To promote the application of NAC genes in wheat improvement by biotechnology, a novel NAC gene designated TaNAC67 was characterized in common wheat. To determine its role, transgenic Arabidopsis overexpressing TaNAC67-GFP controlled by the CaMV-35S promoter was generated and subjected to various abiotic stresses for morphological and physiological assays. Gene expression showed that TaNAC67 was involved in response to drought, salt, cold and ABA treatments. Localization assays revealed that TaNAC67 localized in the nucleus. Morphological analysis indicated the transgenics had enhanced tolerances to drought, salt and freezing stresses, simultaneously supported by enhanced expression of multiple abiotic stress responsive genes and improved physiological traits, including strengthened cell membrane stability, retention of higher chlorophyll contents and Na+ efflux rates, improved photosynthetic potential, and enhanced water retention capability. Overexpression of TaNAC67 resulted in pronounced enhanced tolerances to drought, salt and freezing stresses, therefore it has potential for utilization in transgenic breeding to improve abiotic stress tolerance in crops. PMID:24427285

Molecular biomarkers for progression of intraductal papillary mucinous neoplasm of the pancreas.

PubMed

Kuboki, Yuko; Shimizu, Kyoko; Hatori, Takashi; Yamamoto, Masakazu; Shibata, Noriyuki; Shiratori, Keiko; Furukawa, Toru

2015-03-01

We aimed to identify molecular biomarkers for assessing the progression of intraductal papillary mucinous neoplasm of the pancreas (IPMN). We retrospectively investigated molecular aberrations and their associations with clinicopathological features in 172 IPMNs. GNAS and KRAS mutations were detected in 48% and 56% of IPMNs, respectively. No mutations of EGFR, PIK3CA GNAO1, GNAQ, or GNAI2 were observed. Significant associations were observed between IPMN morphological types and GNAS mutations, KRAS mutations, the expression of phosphorylated MAPK (pMAPK), AKT, and phosphorylated AKT (pAKT), nuclear accumulation of β-catenin, SMAD4 loss, and TP53 overexpression; histological grades and the expression of EGFR, pMAPK, AKT, and pAKT, the nuclear β-catenin, SMAD4 loss, and TP53 overexpression; invasive phenotypes and KRAS mutations, the nuclear β-catenin, and SMAD4 loss; and prognosis and SMAD4 loss and TP53 overexpression. Multivariate analysis to compare prognostic impacts of multiple molecular features revealed that TP53 overexpression was an independent prognostic factor (P = 0.030; hazard ratio, 5.533). These results indicate that mutations in GNAS and KRAS, the expression of EGFR and pMAPK, the nuclear β-catenin, SMAD4 loss, and TP53 overexpression may be relevant for assessing the clinical course of IPMN, including its progression into different morphological types, invasion, and prognosis.

SSU rRNA-based phylogenetic position of the genera Amoeba and Chaos (Lobosea, Gymnamoebia): the origin of gymnamoebae revisited.

PubMed

Bolivar, I; Fahrni, J F; Smirnov, A; Pawlowski, J

2001-12-01

Naked lobose amoebae (gymnamoebae) are among the most abundant group of protists present in all aquatic and terrestrial biotopes. Yet, because of lack of informative morphological characters, the origin and evolutionary history of gymnamoebae are poorly known. The first molecular studies revealed multiple origins for the amoeboid lineages and an extraordinary diversity of amoebae species. Molecular data, however, exist only for a few species of the numerous taxa belonging to this group. Here, we present the small-subunit (SSU) rDNA sequences of four species of typical large gymnamoebae: Amoeba proteus, Amoeba leningradensis, Chaos nobile, and Chaos carolinense. Sequence analysis suggests that the four species are closely related to the species of genera Saccamoeba, Leptomyxa, Rhizamoeba, Paraflabellula, Hartmannella, and Echinamoeba. All of them form a relatively well-supported clade, which corresponds to the subclass Gymnamoebia, in agreement with morphology-based taxonomy. The other gymnamoebae cluster in small groups or branch separately. Their relationships change depending on the type of analysis and the model of nucleotide substitution. All gymnamoebae branch together in Neighbor-Joining analysis with corrections for among-site rate heterogeneity and proportion of invariable sites. This clade, however, is not statistically supported by SSU rRNA gene sequences and further analysis of protein sequence data will be necessary to test the monophyly of gymnamoebae.

Plasma cell morphology in multiple myeloma and related disorders.

PubMed

Ribourtout, B; Zandecki, M

2015-06-01

Normal and reactive plasma cells (PC) are easy to ascertain on human bone marrow films, due to their small mature-appearing nucleus and large cytoplasm, the latter usually deep blue after Giemsa staining. Cytoplasm is filled with long strands of rough endoplasmic reticulum and one large Golgi apparatus (paranuclear hof), demonstrating that PC are dedicated mainly to protein synthesis and excretion (immunoglobulin). Deregulation of the genome may induce clonal expansion of one PC that will lead to immunoglobulin overproduction and eventually to one among the so-called PC neoplasms. In multiple myeloma (MM), the number of PC is over 10% in most patients studied. Changes in the morphology of myeloma PC may be inconspicuous as compared to normal PC (30-50% patients). In other instances PC show one or several morphological changes. One is related to low amount of cytoplasm, defining lymphoplasmacytoid myeloma (10-15% patients). In other cases (40-50% patients), named immature myeloma cases, nuclear-cytoplasmic asynchrony is observed: presence of one nucleolus, finely dispersed chromatin and/or irregular nuclear contour contrast with a still large and blue (mature) cytoplasm. A peculiar morphological change, corresponding to the presence of very immature PC named plasmablasts, is observed in 10-15% cases. Several prognostic morphological classifications have been published, as mature myeloma is related to favorable outcome and immature myeloma, peculiarly plasmablastic myeloma, is related to dismal prognosis. However, such classifications are no longer included in current prognostic schemes. Changes related to the nucleus are very rare in monoclonal gammopathy of unknown significance (MGUS). In contrast, anomalies related to the cytoplasm of PC, including color (flaming cells), round inclusions (Mott cells, Russell bodies), Auer rod-like or crystalline inclusions, are reported in myeloma cases as well as in MGUS and at times in reactive disorders. They do not correspond to malignant changes of PC but are related to abnormal synthesis, trafficking, or excretion of the immunoglobulin that is stored in excess within the cytoplasm. Occurrence of crystalline inclusions within PC may be the first anomaly leading to the diagnosis of adult Fanconi syndrome. After a historical perspective, the authors report on the various morphological aspects of PC that may occur in multiple myeloma and related disorders, and discuss about their clinical and pathophysiological significance. Today, morphological identification and accurate determination of % PC within bone marrow remain ancillary criteria for the diagnosis of MM and help for the diagnosis of rare renal disorders. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Martian rampart crater ejecta - Experiments and analysis of melt-water interaction

NASA Astrophysics Data System (ADS)

Wohletz, K. H.; Sheridan, M. F.

1983-10-01

Viking images of Martian craters with rampart-bordered ejecta deposits reveal distinct impact ejecta morphology when compared to that associated with similar-sized craters on the Moon and Mercury. It is suggested that target water explosively vaporized during impact alters initial ballistic trajectories of ejecta and produces surging flow emplacement. The dispersal of particulates during a series of controlled steam explosions generated by interaction of a thermite melt with water has been experimentally modeled. Study of terrestrial, lobate, volcanic ejecta produced by steam-blast explosions reveals that particle size and vapor to clast volume ratio are primary parameters characterizing the emplacement mechanism and deposit morphology.

The mitochondrial genomes of Campodea fragilis and C. lubbocki(Hexapoda: Diplura): high genetic divergence in a morphologically uniformtaxon

DOE Office of Scientific and Technical Information (OSTI.GOV)

Podsiadlowski, L.; Carapelli, A.; Nardi, F.

2005-12-01

Mitochondrial genomes from two dipluran hexapods of the genus Campodea have been sequenced. Gene order is the same as in most other hexapods and crustaceans. Secondary structures of tRNAs reveal specific structural changes in tRNA-C, tRNA-R, tRNA-S1 and tRNA-S2. Comparative analyses of nucleotide and amino acid composition, as well as structural features of both ribosomal RNA subunits, reveal substantial differences among the analyzed taxa. Although the two Campodea species are morphologically highly uniform, genetic divergence is larger than expected, suggesting a long evolutionary history under stable ecological conditions.

Effects of experimental warming on survival, phenology and morphology of an aquatic insect (Odonata)

PubMed Central

McCauley, Shannon J.; Hammond, John I.; Frances, Dachin N.; Mabry, Karen E.

2014-01-01

1. Organisms can respond to changing climatic conditions in multiple ways including changes in phenology, body size or morphology, and range shifts. Understanding how developmental temperatures affect insect life-history timing and morphology is crucial because body size and morphology affect multiple aspects of life history, including dispersal ability, while phenology can shape population performance and community interactions. 2. We experimentally assessed how developmental temperatures experienced by aquatic larvae affected survival, phenology, and adult morphology of dragonflies (Pachydiplax longipennis). Larvae were reared under 3 environmental temperatures: ambient, +2.5 °C, and +5 °C, corresponding to temperature projections for our study area 50 and 100 years in the future, respectively. Experimental temperature treatments tracked naturally-occurring variation. 3. We found clear effects of temperature in the rearing environment on survival and phenology: dragonflies reared at the highest temperatures had the lowest survival rates, and emerged from the larval stage approximately 3 weeks earlier than animals reared at ambient temperatures. There was no effect of rearing temperature on overall body size. Although neither the relative wing nor thorax size was affected by warming, a non-significant trend towards an interaction between sex and warming in relative thorax size suggests that males may be more sensitive to warming than females, a pattern that should be investigated further. 4. Warming strongly affected survival in the larval stage and the phenology of adult emergence. Understanding how warming in the developmental environment affects later life-history stages is critical to interpreting the consequences of warming for organismal performance. PMID:26028806

The evolution of jaw protrusion mechanics is tightly coupled to bentho-pelagic divergence in damselfishes (Pomacentridae).

PubMed

Cooper, W James; Carter, Casey B; Conith, Andrew J; Rice, Aaron N; Westneat, Mark W

2017-02-15

Most species-rich lineages of aquatic organisms have undergone divergence between forms that feed from the substrate (benthic feeding) and forms that feed from the water column (pelagic feeding). Changes in trophic niche are frequently accompanied by changes in skull mechanics, and multiple fish lineages have evolved highly specialized biomechanical configurations that allow them to protrude their upper jaws toward the prey during feeding. Damselfishes (family Pomacentridae) are an example of a species-rich lineage with multiple trophic morphologies and feeding ecologies. We sought to determine whether bentho-pelagic divergence in the damselfishes is tightly coupled to changes in jaw protrusion ability. Using high-speed video recordings and kinematic analysis, we examined feeding performance in 10 species that include three examples of convergence on herbivory, three examples of convergence on omnivory and two examples of convergence on planktivory. We also utilized morphometrics to characterize the feeding morphology of an additional 40 species that represent all 29 damselfish genera. Comparative phylogenetic analyses were then used to examine the evolution of trophic morphology and biomechanical performance. We find that pelagic-feeding damselfishes (planktivores) are strongly differentiated from extensively benthic-feeding species (omnivores and herbivores) by their jaw protrusion ability, upper jaw morphology and the functional integration of upper jaw protrusion with lower jaw abduction. Most aspects of cranial form and function that separate these two ecological groups have evolved in correlation with each other and the evolution of the functional morphology of feeding in damselfishes has involved repeated convergence in form, function and ecology. © 2017. Published by The Company of Biologists Ltd.

Identification of Lygus hesperus by DNA barcoding reveals insignificant levels of genetic structure among distant and habitat diverse populations.

PubMed

Zhou, Changqing; Kandemir, Irfan; Walsh, Douglas B; Zalom, Frank G; Lavine, Laura Corley

2012-01-01

The western tarnished plant bug Lygus hesperus is an economically important pest that belongs to a complex of morphologically similar species that makes identification problematic. The present study provides evidence for the use of DNA barcodes from populations of L. hesperus from the western United States of America for accurate identification. This study reports DNA barcodes for 134 individuals of the western tarnished plant bug from alfalfa and strawberry agricultural fields in the western United States of America. Sequence divergence estimates of <3% reveal that morphologically variable individuals presumed to be L. hesperus were accurately identified. Paired estimates of F(st) and subsequent estimates of gene flow show that geographically distinct populations of L. hesperus are genetically similar. Therefore, our results support and reinforce the relatively recent (<100 years) migration of the western tarnished plant bug into agricultural habitats across the western United States. This study reveals that despite wide host plant usage and phenotypically plastic morphological traits, the commonly recognized western tarnished plant bug belongs to a single species, Lygus hesperus. In addition, no significant genetic structure was found for the geographically diverse populations of western tarnished plant bug used in this study.

High efficient perovskite solar cell material CH3NH3PbI3: Synthesis of films and their characterization

NASA Astrophysics Data System (ADS)

Bera, Amrita Mandal; Wargulski, Dan Ralf; Unold, Thomas

2018-04-01

Hybrid organometal perovskites have been emerged as promising solar cell material and have exhibited solar cell efficiency more than 20%. Thin films of Methylammonium lead iodide CH3NH3PbI3 perovskite materials have been synthesized by two different (one step and two steps) methods and their morphological properties have been studied by scanning electron microscopy and optical microscope imaging. The morphology of the perovskite layer is one of the most important parameters which affect solar cell efficiency. The morphology of the films revealed that two steps method provides better surface coverage than the one step method. However, the grain sizes were smaller in case of two steps method. The films prepared by two steps methods on different substrates revealed that the grain size also depend on the substrate where an increase of the grain size was found from glass substrate to FTO with TiO2 blocking layer to FTO without any change in the surface coverage area. Present study reveals that an improved quality of films can be obtained by two steps method by an optimization of synthesis processes.

Eco-evolution in size-structured ecosystems: simulation case study of rapid morphological changes in alewife.

PubMed

Kang, Jung Koo; Thibert-Plante, Xavier

2017-02-27

Over the last 300 years, interactions between alewives and zooplankton communities in several lakes in the U.S. have caused the alewives' morphology to transition rapidly from anadromous to landlocked. Lakes with landlocked alewives contain smaller-bodied zooplankton than those without alewives. Landlocked adult alewives display smaller body sizes, narrower gapes, smaller inter-gill-raker spacings, reach maturity at an earlier age, and are less fecund than anadromous alewives. Additionally, landlocked alewives consume pelagic prey exclusively throughout their lives whereas anadromous alewives make an ontogenetic transition from pelagic to littoral prey. These rapid, well-documented changes in the alewives' morphology provide important insights into the morphological evolution of fish. Predicting the morphological evolution of fish is crucial for fisheries and ecosystem management, but the involvement of multiple trophic interactions make predictions difficult. To obtain an improved understanding of rapid morphological change in fish, we developed an individual-based model that simulated rapid changes in the body size and gill-raker count of a fish species in a hypothetical, size-structured prey community. Model parameter values were based mainly on data from empirical studies on alewives. We adopted a functional trait approach; consequently, the model explicitly describes the relationships between prey body size, alewife body size, and alewife gill-raker count. We sought to answer two questions: (1) How does the impact of alewife populations on prey feed back to impact alewife size and gill raker number under several alternative scenarios? (2) Will the trajectory of the landlocked alewives' morphological evolution change after 150-300 years in freshwater? Over the first 250 years, the alewives' numbers of gill-rakers only increased when reductions in their body size substantially improved their ability to forage for small prey. Additionally, alewives' gill-raker counts increased more rapidly as the adverse effects of narrow gill-raker spacings on foraging for large prey were made less severe. For the first 150-250 years, alewives' growth decreased monotonically, and their gill-raker number increased monotonically. After the first 150-250 years, however, the alewives exhibited multiple evolutionary morphological trajectories in different trophic settings. In several of these settings, their evolutionary trajectories even reversed after the first 150-250 years. Alewives affected the abundance and morphology of their prey, which in turn changed the abundance and morphology of the alewives. Complex low-trophic-level interactions can alter the abundance and characteristics of alewives. This study suggests that the current morphology of recently (∼300 years)-landlocked alewives may not represent an evolutionarily stable state.

On the Origins of Starburst and Poststarburst Galaxies in Nearby Clusters

NASA Astrophysics Data System (ADS)

Caldwell, Nelson; Rose, James A.; Dendy, Kristi

1999-01-01

Hubble Space Telescope (HST) Wide Field Planetary Camera 2 images in B (F450W) and I (F814W) have been obtained for three starburst (SB) and two poststarburst (PSB) galaxies in the Coma Cluster and for three such galaxies in the cluster DC 048-52. V (F555W) and I images for an additional PSB galaxy in Coma have been extracted from the HST archive. Six of these galaxies were previously classified as E/S0 on the basis of ground-based images, two as Sa, and the other as an irregular. The HST images reveal these SB/PSB galaxies to be heterogeneous in morphology. Nevertheless, a common theme is that many of them, especially the SB galaxies, tend to have centralized spiral structure that appears simply as a bright ``bulge'' on ground-based images. In addition, while some PSB galaxies exhibit distinct spiral structure, on the whole they have smoother morphologies than the SB galaxies. The morphologies and luminosity profiles are generally consistent with substantial starbursts, in the form of centralized spiral structure (the SB galaxies), that fade into smoother morphologies (the PSB galaxies), with lingering spectroscopic evidence for past central starbursts. An important point is that the PSB galaxies retain disks; i.e., they have not evolved into spheroidal systems. While the morphologies revealed in the HST images are heterogeneous, and thus may not fit well into a single picture, we see evidence in several cases that the morphologies and centralized star formation have been driven by external tidal perturbations. We discuss several physical mechanisms for inducing star formation in cluster galaxies with a view toward explaining the particular morphologies seen in the HST images.

Natural Genetic Variation and Candidate Genes for Morphological Traits in Drosophila melanogaster

PubMed Central

Carreira, Valeria Paula; Mensch, Julián; Hasson, Esteban; Fanara, Juan José

2016-01-01

Body size is a complex character associated to several fitness related traits that vary within and between species as a consequence of environmental and genetic factors. Latitudinal and altitudinal clines for different morphological traits have been described in several species of Drosophila and previous work identified genomic regions associated with such variation in D. melanogaster. However, the genetic factors that orchestrate morphological variation have been barely studied. Here, our main objective was to investigate genetic variation for different morphological traits associated to the second chromosome in natural populations of D. melanogaster along latitudinal and altitudinal gradients in Argentina. Our results revealed weak clinal signals and a strong population effect on morphological variation. Moreover, most pairwise comparisons between populations were significant. Our study also showed important within-population genetic variation, which must be associated to the second chromosome, as the lines are otherwise genetically identical. Next, we examined the contribution of different candidate genes to natural variation for these traits. We performed quantitative complementation tests using a battery of lines bearing mutated alleles at candidate genes located in the second chromosome and six second chromosome substitution lines derived from natural populations which exhibited divergent phenotypes. Results of complementation tests revealed that natural variation at all candidate genes studied, invected, Fasciclin 3, toucan, Reticulon-like1, jing and CG14478, affects the studied characters, suggesting that they are Quantitative Trait Genes for morphological traits. Finally, the phenotypic patterns observed suggest that different alleles of each gene might contribute to natural variation for morphological traits. However, non-additive effects cannot be ruled out, as wild-derived strains differ at myriads of second chromosome loci that may interact epistatically with mutant alleles. PMID:27459710

An Amoeba/Zoozanthellae Consortium as a Model System for Animal/Algal Symbiosis

DTIC Science & Technology

1991-06-18

extensive multiple fission of Morph-1 cells. Morphology-V: Minigiants - 15-40 microns, complex net-like morphology resulted from fussion of mini oells...seaweeds and sea water (1:1) and autoclaved (20 minutes, 120aC, 250 psi). Nuclear staining: For staining the nuclei, cells were allowed to attach and...water were added (lug/ml) and the amoebae were observed under a fluorescent microscope. Nuclear stains penetrated fixed cells easily and brightly

Numerical modeling of planetary-scale waves on Jupiter

NASA Astrophysics Data System (ADS)

Cosentino, Richard; Morales-Juberias, Raul; Simon, Amy

2014-11-01

The atmosphere of Jupiter has multiple alternating east-wind wind jets with different cloud morphologies some of which can be explained by the presence of atmospheric waves. One jet feature observed by Cassini and HST at 30N, called the Jovian Ribbon for its similarity to Saturn's Ribbon, displays chaotic cloud morphology caused by multiple wave components with dominating planetary scale wave-numbers ranging from 13 to 30. Both the cloud morphology and the dominant wave numbers observed change as a function of time and correlate to changes in the jet's speed. The average speed of the westward jet where this Jovian Ribbon is found is small compared to other notable jets that display wave behavior, namely the high velocity eastward jets at 7N (hot spots) and 7S (chevrons). We present the results of numerical simulations that show how attributes like jet speed, location, vertical shear and other background properties of the atmosphere (e.g. static stability) contribute to the development and evolution of wave structures in jets similar to those observed. Additionally, we explore the effects of local convective events and other atmospheric disturbances such as spots, on the morphology of these jets and waves. This work was supported by NASA PATM grant number NNX14AH47G. Computing resources for this research were provided by NMT and Yellowstone at CISL.

Many-to-one form-to-function mapping weakens parallel morphological evolution.

PubMed

Thompson, Cole J; Ahmed, Newaz I; Veen, Thor; Peichel, Catherine L; Hendry, Andrew P; Bolnick, Daniel I; Stuart, Yoel E

2017-11-01

Evolutionary ecologists aim to explain and predict evolutionary change under different selective regimes. Theory suggests that such evolutionary prediction should be more difficult for biomechanical systems in which different trait combinations generate the same functional output: "many-to-one mapping." Many-to-one mapping of phenotype to function enables multiple morphological solutions to meet the same adaptive challenges. Therefore, many-to-one mapping should undermine parallel morphological evolution, and hence evolutionary predictability, even when selection pressures are shared among populations. Studying 16 replicate pairs of lake- and stream-adapted threespine stickleback (Gasterosteus aculeatus), we quantified three parts of the teleost feeding apparatus and used biomechanical models to calculate their expected functional outputs. The three feeding structures differed in their form-to-function relationship from one-to-one (lower jaw lever ratio) to increasingly many-to-one (buccal suction index, opercular 4-bar linkage). We tested for (1) weaker linear correlations between phenotype and calculated function, and (2) less parallel evolution across lake-stream pairs, in the many-to-one systems relative to the one-to-one system. We confirm both predictions, thus supporting the theoretical expectation that increasing many-to-one mapping undermines parallel evolution. Therefore, sole consideration of morphological variation within and among populations might not serve as a proxy for functional variation when multiple adaptive trait combinations exist. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

Zebrafish no isthmus reveals a role for pax2.1 in tubule differentiation and patterning events in the pronephric primordia.

PubMed

Majumdar, A; Lun, K; Brand, M; Drummond, I A

2000-05-01

Pax genes are important developmental regulators and function at multiple stages of vertebrate kidney organogenesis. In this report, we have used the zebrafish pax2.1 mutant no isthmus to investigate the role for pax2.1 in development of the pronephros. We demonstrate a requirement for pax2.1 in multiple aspects of pronephric development including tubule and duct epithelial differentiation and cloaca morphogenesis. Morphological analysis demonstrates that noi(- )larvae specifically lack pronephric tubules while glomerular cell differentiation is unaffected. In addition, pax2.1 expression in the lateral cells of the pronephric primordium is required to restrict the domains of Wilms' tumor suppressor (wt1) and vascular endothelial growth factor (VEGF) gene expression to medial podocyte progenitors. Ectopic podocyte-specific marker expression in pronephric duct cells correlates with loss of expression of the pronephric tubule and duct-specific markers mAb 3G8 and a Na(+)/K(+) ATPase (&agr;)1 subunit. The results suggest that the failure in pronephric tubule differentiation in noi arises from a patterning defect during differentiation of the pronephric primordium and that mutually inhibitory regulatory interactions play an important role in defining the boundary between glomerular and tubule progenitors in the forming nephron.

Schwann cell-specific JAM-C-deficient mice reveal novel expression and functions for JAM-C in peripheral nerves.

PubMed

Colom, Bartomeu; Poitelon, Yannick; Huang, Wenlong; Woodfin, Abigail; Averill, Sharon; Del Carro, Ubaldo; Zambroni, Desirée; Brain, Susan D; Perretti, Mauro; Ahluwalia, Amrita; Priestley, John V; Chavakis, Triantafyllos; Imhof, Beat A; Feltri, M Laura; Nourshargh, Sussan

2012-03-01

Junctional adhesion molecule-C (JAM-C) is an adhesion molecule expressed at junctions between adjacent endothelial and epithelial cells and implicated in multiple inflammatory and vascular responses. In addition, we recently reported on the expression of JAM-C in Schwann cells (SCs) and its importance for the integrity and function of peripheral nerves. To investigate the role of JAM-C in neuronal functions further, mice with a specific deletion of JAM-C in SCs (JAM-C SC KO) were generated. Compared to wild-type (WT) controls, JAM-C SC KO mice showed electrophysiological defects, muscular weakness, and hypersensitivity to mechanical stimuli. In addressing the underlying cause of these defects, nerves from JAM-C SC KO mice were found to have morphological defects in the paranodal region, exhibiting increased nodal length as compared to WTs. The study also reports on previously undetected expressions of JAM-C, namely on perineural cells, and in line with nociception defects of the JAM-C SC KO animals, on finely myelinated sensory nerve fibers. Collectively, the generation and characterization of JAM-C SC KO mice has provided unequivocal evidence for the involvement of SC JAM-C in the fine organization of peripheral nerves and in modulating multiple neuronal responses.

The fish diversity in the upper reaches of the Salween River, Nujiang River, revealed by DNA barcoding.

PubMed

Chen, Weitao; Ma, Xiuhui; Shen, Yanjun; Mao, Yuntao; He, Shunping

2015-11-30

Nujiang River (NR), an essential component of the biodiversity hotspot of the Mountains of Southwest China, possesses a characteristic fish fauna and contains endemic species. Although previous studies on fish diversity in the NR have primarily consisted of listings of the fish species observed during field collections, in our study, we DNA-barcoded 1139 specimens belonging to 46 morphologically distinct fish species distributed throughout the NR basin by employing multiple analytical approaches. According to our analyses, DNA barcoding is an efficient method for the identification of fish by the presence of barcode gaps. However, three invasive species are characterized by deep conspecific divergences, generating multiple lineages and Operational Taxonomic Units (OTUs), implying the possibility of cryptic species. At the other end of the spectrum, ten species (from three genera) that are characterized by an overlap between their intra- and interspecific genetic distances form a single genetic cluster and share haplotypes. The neighbor-joining phenogram, Barcode Index Numbers (BINs) and Automatic Barcode Gap Discovery (ABGD) identified 43 putative species, while the General Mixed Yule-coalescence (GMYC) identified five more OTUs. Thus, our study established a reliable DNA barcode reference library for the fish in the NR and sheds new light on the local fish diversity.

The fish diversity in the upper reaches of the Salween River, Nujiang River, revealed by DNA barcoding

PubMed Central

Chen, Weitao; Ma, Xiuhui; Shen, Yanjun; Mao, Yuntao; He, Shunping

2015-01-01

Nujiang River (NR), an essential component of the biodiversity hotspot of the Mountains of Southwest China, possesses a characteristic fish fauna and contains endemic species. Although previous studies on fish diversity in the NR have primarily consisted of listings of the fish species observed during field collections, in our study, we DNA-barcoded 1139 specimens belonging to 46 morphologically distinct fish species distributed throughout the NR basin by employing multiple analytical approaches. According to our analyses, DNA barcoding is an efficient method for the identification of fish by the presence of barcode gaps. However, three invasive species are characterized by deep conspecific divergences, generating multiple lineages and Operational Taxonomic Units (OTUs), implying the possibility of cryptic species. At the other end of the spectrum, ten species (from three genera) that are characterized by an overlap between their intra- and interspecific genetic distances form a single genetic cluster and share haplotypes. The neighbor-joining phenogram, Barcode Index Numbers (BINs) and Automatic Barcode Gap Discovery (ABGD) identified 43 putative species, while the General Mixed Yule-coalescence (GMYC) identified five more OTUs. Thus, our study established a reliable DNA barcode reference library for the fish in the NR and sheds new light on the local fish diversity. PMID:26616046

Functional capacity following univentricular repair--midterm outcome.

PubMed

Sen, Supratim; Bandyopadhyay, Biswajit; Eriksson, Peter; Chattopadhyay, Amitabha

2012-01-01

Previous studies have seldom compared functional capacity in children following Fontan procedure alongside those with Glenn operation as destination therapy. We hypothesized that Fontan circulation enables better midterm submaximal exercise capacity as compared to Glenn physiology and evaluated this using the 6-minute walk test. Fifty-seven children aged 5-18 years with Glenn (44) or Fontan (13) operations were evaluated with standard 6-minute walk protocols. Baseline SpO(2) was significantly lower in Glenn patients younger than 10 years compared to Fontan counterparts and similar in the two groups in older children. Postexercise SpO(2) fell significantly in Glenn patients compared to the Fontan group. There was no statistically significant difference in baseline, postexercise, or postrecovery heart rates (HRs), or 6-minute walk distances in the two groups. Multiple regression analysis revealed lower resting HR, higher resting SpO(2) , and younger age at latest operation to be significant determinants of longer 6-minute walk distance. Multiple regression analysis also established that younger age at operation, higher resting SpO(2) , Fontan operation, lower resting HR, and lower postexercise HR were significant determinants of higher postexercise SpO(2) . Younger age at operation and exercise, lower resting HR and postexercise HR, higher resting SpO(2) and postexercise SpO(2) , and dominant ventricular morphology being left ventricular or indeterminate/mixed had significant association with better 6-minute work on multiple regression analysis. Lower resting HR had linear association with longer 6-minute walk distances in the Glenn patients. Compared to Glenn physiology, Fontan operation did not have better submaximal exercise capacity assessed by walk distance or work on multiple regression analysis. Lower resting HR, higher resting SpO(2) , and younger age at operation were factors uniformly associated with better submaximal exercise capacity. © 2012 Wiley Periodicals, Inc.

Morphology and formation mechanism in precipitation of calcite induced by Curvibacter lanceolatus strain HJ-1

NASA Astrophysics Data System (ADS)

Zhang, Chonghong; Li, Fuchun; Lv, Jiejie

2017-11-01

Precipitation of calcium carbobate induced by microbial activities is common occurrence in controlled solution, but the formation mechanism and morphology in precipitation of calcite in solution systems is unclear, and the role of microbes is disputed. Here, culture experiment was performed for 50 days using the Curvibacter lanceolatus strain HJ-1 in a M2 culture medium, and the phase composition and morphology of the precipitates were characterized by the X-ray diffraction (XRD), Fourier transform infrared (FT-IR), and scanning electron microscopy (SEM) techniques. We show that the precipitation processes in our experiment lead to unusual morphologies of crystals corresponding to different growth stages, and the morphologies of the precipitated crystal aggregates ranging from the main rod-, cross-, star-, cauliflower-like morphologies to spherulitic structure. The complex and unusual morphologies of the precipitated calcite by strain HJ-1 may provide a reference point for better understanding the biomineralization mechanism of calcite, moreover, morphological transition of minerals revealed that the multi-ply crystals-aggregation mechanism for calcite growth in crystallisation media.

The role of habitat shift in the evolution of lizard morphology: evidence from tropical Tropidurus

PubMed Central

Vitt, Laurie J.; Caldwell, Janalee P.; Zani, Peter A.; Titus, Tom A.

1997-01-01

We compared morphology of two geographically close populations of the tropical lizard Tropidurus hispidus to test the hypothesis that habitat structure influences the evolution of morphology and ecology at the population level. T. hispidus isolated on a rock outcrop surrounded by tropical forest use rock crevices for refuge and appear dorsoventrally compressed compared with those in open savanna. A principal components analysis revealed that the populations were differentially distributed along an axis representing primarily three components of shape: body width, body height, and hind-leg length. Morphological divergence was supported by a principal components analysis of size-free morphological variables. Mitochondrial DNA sequences of ATPase 6 indicate that these populations are closely related relative to other T. hispidus, the rock outcrop morphology and ecology are derived within T. hispidus, and morphological and ecological divergence has occurred more rapidly than genetic divergence. This suggests that natural selection can rapidly adjust morphology and ecology in response to a recent history of exposure to habitats differing in structure, a result heretofore implied from comparative studies among lizard species. PMID:9108063

The role of habitat shift in the evolution of lizard morphology: evidence from tropical Tropidurus.

PubMed

Vitt, L J; Caldwell, J P; Zani, P A; Titus, T A

1997-04-15

We compared morphology of two geographically close populations of the tropical lizard Tropidurus hispidus to test the hypothesis that habitat structure influences the evolution of morphology and ecology at the population level. T. hispidus isolated on a rock outcrop surrounded by tropical forest use rock crevices for refuge and appear dorsoventrally compressed compared with those in open savanna. A principal components analysis revealed that the populations were differentially distributed along an axis representing primarily three components of shape: body width, body height, and hind-leg length. Morphological divergence was supported by a principal components analysis of size-free morphological variables. Mitochondrial DNA sequences of ATPase 6 indicate that these populations are closely related relative to other T. hispidus, the rock outcrop morphology and ecology are derived within T. hispidus, and morphological and ecological divergence has occurred more rapidly than genetic divergence. This suggests that natural selection can rapidly adjust morphology and ecology in response to a recent history of exposure to habitats differing in structure, a result heretofore implied from comparative studies among lizard species.

Anomalous charge transport in conjugated polymers reveals underlying mechanisms of trapping and percolation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mollinger, Sonya A.; Salleo, Alberto; Spakowitz, Andrew J.

While transport in conjugated polymers has many similarities to that in crystalline inorganic materials, several key differences reveal the unique relationship between the morphology of polymer films and the charge mobility. We develop a model that directly incorporates the molecular properties of the polymer film and correctly predicts these unique transport features. At low degree of polymerization, the increase of the mobility with the polymer chain length reveals trapping at chain ends, and saturation of the mobility at high degree of polymerization results from conformational traps within the chains. Similarly, the inverse field dependence of the mobility reveals that transportmore » on single polymer chains is characterized by the ability of the charge to navigate around kinks and loops in the chain. Lastly, these insights emphasize the connection between the polymer conformations and the transport and thereby offer a route to designing improved device morphologies through molecular design and materials processing.« less

Anomalous charge transport in conjugated polymers reveals underlying mechanisms of trapping and percolation

DOE PAGES

Mollinger, Sonya A.; Salleo, Alberto; Spakowitz, Andrew J.

2016-11-10

While transport in conjugated polymers has many similarities to that in crystalline inorganic materials, several key differences reveal the unique relationship between the morphology of polymer films and the charge mobility. We develop a model that directly incorporates the molecular properties of the polymer film and correctly predicts these unique transport features. At low degree of polymerization, the increase of the mobility with the polymer chain length reveals trapping at chain ends, and saturation of the mobility at high degree of polymerization results from conformational traps within the chains. Similarly, the inverse field dependence of the mobility reveals that transportmore » on single polymer chains is characterized by the ability of the charge to navigate around kinks and loops in the chain. Lastly, these insights emphasize the connection between the polymer conformations and the transport and thereby offer a route to designing improved device morphologies through molecular design and materials processing.« less

Diet-Morphology Correlations in the Radiation of South American Geophagine Cichlids (Perciformes: Cichlidae: Cichlinae)

PubMed Central

López-Fernández, Hernán; Winemiller, Kirk O.; Montaña, Carmen; Honeycutt, Rodney L.

2012-01-01

Genera within the South American cichlid tribe Geophagini display specialized feeding and reproductive strategies, with some taxa specialized for both substrate-sifting and mouth brooding. Several lineages within the clade also possess an epibranchial lobe (EBL), a unique pharyngeal structure that has been proposed to have a function in feeding and/or mouth brooding. A recently published genus-level phylogeny of Neotropical cichlids was used as the evolutionary framework for investigating the evolution of morphological features presumably correlated with diet and mouth brooding in the tribe Geophagini. We tested for possible associations between the geophagine epibranchial lobe and benthic feeding and mouth brooding. We also addressed whether the EBL may be associated with unique patterns of diversification in certain geophagine clades. Tests of binary character correlations revealed the EBL was significantly associated with mouth brooding. We also tested for a relationship between diet and morphology. We analyzed stomach contents and morphometric variation among 21 species, with data for two additional species obtained from the literature. Principal Components Analysis revealed axes of morphological variation significantly correlated with piscivory and benthivory, and both morphology and diet were significantly associated with phylogeny. These results suggest that the EBL could be an adaptation for either feeding or mouth brooding. The EBL, however, was not associated with species richness or accelerated rates of phyletic diversification. PMID:22485154

Impact of oleylamine: Oleic acid ratio on the morphology of yttria nanomaterials

DOE PAGES

Treadwell, LaRico J.; Boyle, Timothy J.; Bell, Nelson S.; ...

2017-03-31

In this paper, the impact on the final morphology of yttria (Y 2O 3) nanoparticles from different ratios (100/0, 90/10, 65/35, and 50/50) of oleylamine (ON) and oleic acid (OA) via a solution precipitation route has been determined. In all instances, powder X-ray diffraction indicated that the cubic Y 2O 3 phase (PDF #00-025-1200) with the space group I-3a (206) had been formed. Analysis of the collected FTIR data revealed the presence of stretches and bends consistent with ON and OA, for all ratios investigated, except the 100/0. Transmission electron microscopy images revealed regular and elongated hexagons were produced formore » the ON (100/0) sample. As OA was added, the nanoparticle morphology changed to lamellar pillars (90/10), then irregular particles (65/35), and finally plates (50/50). The formation of the hexagonal-shaped nanoparticles was determined to be due to the preferential adsorption of ON onto the {101} planes. As OA was added to the reaction mixture, it was found that the {111} planes were preferentially coated, replacing ON from the surface, resulting in the various morphologies noted. The roles of the ratio of ON/OA in the synthesis of the nanocrystals were elucidated in the formation of the various Y 2O 3 morphologies, as well as a possible growth mechanism based on the experimental data.« less

The Separability of Morphological Processes from Semantic Meaning and Syntactic Class in Production of Single Words: Evidence from the Hebrew Root Morpheme.

PubMed

Deutsch, Avital

2016-02-01

In the present study we investigated to what extent the morphological facilitation effect induced by the derivational root morpheme in Hebrew is independent of semantic meaning and grammatical information of the part of speech involved. Using the picture-word interference paradigm with auditorily presented distractors, Experiment 1 compared the facilitation effect induced by semantically transparent versus semantically opaque morphologically related distractor words (i.e., a shared root) on the production latency of bare nouns. The results revealed almost the same amount of facilitation for both relatedness conditions. These findings accord with the results of the few studies that have addressed this issue in production in Indo-European languages, as well as previous studies in written word perception in Hebrew. Experiment 2 compared the root's facilitation effect, induced by morphologically related nominal versus verbal distractors, on the production latency of bare nouns. The results revealed a facilitation effect of similar size induced by the shared root, regardless of the distractor's part of speech. It is suggested that the principle that governs lexical organization at the level of morphology, at least for Hebrew roots, is form-driven and independent of semantic meaning. This principle of organization crosses the linguistic domains of production and written word perception, as well as grammatical organization according to part of speech.

Martian Impact Craters as Revealed by MGS and Odyssey

NASA Technical Reports Server (NTRS)

Barlow, N. G.

2005-01-01

A variety of ejecta and interior morphologies were revealed for martian impact craters by Viking imagery. Numerous studies have classified these ejecta and interior morphologies and looked at how these morphologies correlate with crater diameter, latitude, terrain, and elevation [1, 2, 3, 4]. Many of these features, particularly the layered (fluidized) ejecta morphologies and central pits, have been proposed to result when the crater formed in target material containing high concentrations of volatiles. The Catalog of Large Martian Impact Craters was originally derived from the Viking 1:2,000,000 photomosaics and contains information on 42,283 impact craters 5-km diameter distributed across the entire martian surface. The information in this Catalog has been used to study the distributions of craters displaying specific ejecta and interior morphologies in an attempt to understand the environmental conditions which give rise to these features and to estimate the areal and vertical extents of subsurface volatile reservoirs [4, 5]. The Catalog is currently undergoing revision utilizing Mars Global Surveyor (MGS) and Mars Odyssey data [6]. The higher resolution multispectral imagery is resulting in numerous revisions to the original classifications and the addition of new elemental, thermophysical, and topographic data is allowing new insights into the environmental conditions under which these features form. A few of the new results from analysis of data in the revised Catalog are discussed below.

Extracting hurricane eye morphology from spaceborne SAR images using morphological analysis

NASA Astrophysics Data System (ADS)

Lee, Isabella K.; Shamsoddini, Ali; Li, Xiaofeng; Trinder, John C.; Li, Zeyu

2016-07-01

Hurricanes are among the most destructive global natural disasters. Thus recognizing and extracting their morphology is important for understanding their dynamics. Conventional optical sensors, due to cloud cover associated with hurricanes, cannot reveal the intense air-sea interaction occurring at the sea surface. In contrast, the unique capabilities of spaceborne synthetic aperture radar (SAR) data for cloud penetration, and its backscattering signal characteristics enable the extraction of the sea surface roughness. Therefore, SAR images enable the measurement of the size and shape of hurricane eyes, which reveal their evolution and strength. In this study, using six SAR hurricane images, we have developed a mathematical morphology method for automatically extracting the hurricane eyes from C-band SAR data. Skeleton pruning based on discrete skeleton evolution (DSE) was used to ensure global and local preservation of the hurricane eye shape. This distance weighted algorithm applied in a hierarchical structure for extraction of the edges of the hurricane eyes, can effectively avoid segmentation errors by reducing redundant skeletons attributed to speckle noise along the edges of the hurricane eye. As a consequence, the skeleton pruning has been accomplished without deficiencies in the key hurricane eye skeletons. A morphology-based analyses of the subsequent reconstructions of the hurricane eyes shows a high degree of agreement with the hurricane eye areas derived from reference data based on NOAA manual work.

Impact of oleylamine: Oleic acid ratio on the morphology of yttria nanomaterials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Treadwell, LaRico J.; Boyle, Timothy J.; Bell, Nelson S.

In this paper, the impact on the final morphology of yttria (Y 2O 3) nanoparticles from different ratios (100/0, 90/10, 65/35, and 50/50) of oleylamine (ON) and oleic acid (OA) via a solution precipitation route has been determined. In all instances, powder X-ray diffraction indicated that the cubic Y 2O 3 phase (PDF #00-025-1200) with the space group I-3a (206) had been formed. Analysis of the collected FTIR data revealed the presence of stretches and bends consistent with ON and OA, for all ratios investigated, except the 100/0. Transmission electron microscopy images revealed regular and elongated hexagons were produced formore » the ON (100/0) sample. As OA was added, the nanoparticle morphology changed to lamellar pillars (90/10), then irregular particles (65/35), and finally plates (50/50). The formation of the hexagonal-shaped nanoparticles was determined to be due to the preferential adsorption of ON onto the {101} planes. As OA was added to the reaction mixture, it was found that the {111} planes were preferentially coated, replacing ON from the surface, resulting in the various morphologies noted. The roles of the ratio of ON/OA in the synthesis of the nanocrystals were elucidated in the formation of the various Y 2O 3 morphologies, as well as a possible growth mechanism based on the experimental data.« less

Paleogenetic Analyses Reveal Unsuspected Phylogenetic Affinities between Mice and the Extinct Malpaisomys insularis, an Endemic Rodent of the Canaries

PubMed Central

Gros-Balthazard, Muriel; Hughes, Sandrine; Alcover, Josep Antoni; Hutterer, Rainer; Rando, Juan Carlos; Michaux, Jacques; Hänni, Catherine

2012-01-01

Background The lava mouse, Malpaisomys insularis, was endemic to the Eastern Canary islands and became extinct at the beginning of the 14th century when the Europeans reached the archipelago. Studies to determine Malpaisomys' phylogenetic affinities, based on morphological characters, remained inconclusive because morphological changes experienced by this insular rodent make phylogenetic investigations a real challenge. Over 20 years since its first description, Malpaisomys' phylogenetic position remains enigmatic. Methodology/Principal Findings In this study, we resolved this issue using molecular characters. Mitochondrial and nuclear markers were successfully amplified from subfossils of three lava mouse samples. Molecular phylogenetic reconstructions revealed, without any ambiguity, unsuspected relationships between Malpaisomys and extant mice (genus Mus, Murinae). Moreover, through molecular dating we estimated the origin of the Malpaisomys/mouse clade at 6.9 Ma, corresponding to the maximal age at which the archipelago was colonised by the Malpaisomys ancestor via natural rafting. Conclusion/Significance This study reconsiders the derived morphological characters of Malpaisomys in light of this unexpected molecular finding. To reconcile molecular and morphological data, we propose to consider Malpaisomys insularis as an insular lineage of mouse. PMID:22363563

Morphology informed by phylogeny reveals unexpected patterns of species differentiation in the aquatic moss Rhynchostegium riparioides s.l.

PubMed

Hutsemékers, Virginie; Vieira, Cristiana C; Ros, Rosa María; Huttunen, Sanna; Vanderpoorten, Alain

2012-02-01

Bryophyte floras typically exhibit extremely low levels of endemism. The interpretation, that this might reflect taxonomic shortcomings, is tested here for the Macaronesian flora, using the moss species complex of Rhynchostegium riparioides as a model. The deep polyphyly of R. riparioides across its distribution range reveals active differentiation that better corresponds to geographic than morphological differences. Morphometric analyses are, in fact, blurred by a size gradient that accounts for 80% of the variation observed among gametophytic traits. The lack of endemic diversification observed in R. riparioides in Macaronesia weakens the idea that the low rates of endemism observed in the Macaronesian bryophyte flora might solely be explained by taxonomic shortcomings. To the reverse, the striking polyphyly of North American and European lineages of R. riparioides suggests that the similarity between the floras of these continents has been over-emphasized. Discriminant analyses point to the existence of morphological discontinuities among the lineages resolved by the molecular phylogeny. The global rate of error associated to species identification based on morphology (0.23) indicates, however, that intergradation of shape and size characters among species in the group challenges their identification. Copyright © 2011 Elsevier Inc. All rights reserved.

Blending Gelators to Tune Gel Structure and Probe Anion-Induced Disassembly

PubMed Central

Foster, Jonathan A; Edkins, Robert M; Cameron, Gary J; Colgin, Neil; Fucke, Katharina; Ridgeway, Sam; Crawford, Andrew G; Marder, Todd B; Beeby, Andrew; Cobb, Steven L; Steed, Jonathan W

2014-01-01

Blending different low molecular weight gelators (LMWGs) provides a convenient route to tune the properties of a gel and incorporate functionalities such as fluorescence. Blending a series of gelators having a common bis-urea motif, and functionalised with different amino acid-derived end-groups and differing length alkylene spacers is reported. Fluorescent gelators incorporating 1-and 2-pyrenyl moieties provide a probe of the mixed systems alongside structural and morphological data from powder diffraction and electron microscopy. Characterisation of the individual gelators reveals that although the expected α-urea tape motif is preserved, there is considerable variation in the gelation properties, molecular packing, fibre morphology and rheological behaviour. Mixing of the gelators revealed examples in which: 1) the gels formed separate, orthogonal networks maintaining their own packing and morphology, 2) the gels blended together into a single network, either adopting the packing and morphology of one gelator, or 3) a new structure not seen for either of the gelators individually was created. The strong binding of the urea functionalities to anions was exploited as a means of breaking down the gel structure, and the use of fluorescent gel blends provides new insights into anion-mediated gel dissolution. PMID:24302604

Structure of the Shroom-Rho Kinase Complex Reveals a Binding Interface with Monomeric Shroom That Regulates Cell Morphology and Stimulates Kinase Activity

DOE PAGES

Zalewski, Jenna K.; Mo, Joshua H.; Heber, Simone; ...

2016-10-10

Shroom-mediated remodeling of the actomyosin cytoskeleton is a critical driver of cellular shape and tissue morphology that underlies the development of many tissues including the neural tube, eye, intestines, and vasculature. Shroom uses a conserved SD2 domain to direct the subcellular localization of Rho-associated kinase (Rock), which in turn drives changes in the cytoskeleton and cellular morphology through its ability to phosphorylate and activate non-muscle myosin II. Here in this paper, we present the structure of the human Shroom-Rock binding module, revealing an unexpected stoichiometry for Shroom in which two Shroom SD2 domains bind independent surfaces on Rock. Mutation ofmore » interfacial residues impaired Shroom-Rock binding in vitro and resulted in altered remodeling of the cytoskeleton and loss of Shroom-mediated changes in cellular morphology. In addition, we provide the first direct evidence that Shroom can function as a Rock activator. These data provide molecular insight into the Shroom-Rock interface and demonstrate that Shroom directly participates in regulating cytoskeletal dynamics, adding to its known role in Rock localization.« less

Characterization of multiple SPS knockout mutants reveals redundant functions of the four Arabidopsis sucrose phosphate synthase isoforms in plant viability, and strongly indicates that enhanced respiration and accelerated starch turnover can alleviate the blockage of sucrose biosynthesis.

PubMed

Bahaji, Abdellatif; Baroja-Fernández, Edurne; Ricarte-Bermejo, Adriana; Sánchez-López, Ángela María; Muñoz, Francisco José; Romero, Jose M; Ruiz, María Teresa; Baslam, Marouane; Almagro, Goizeder; Sesma, María Teresa; Pozueta-Romero, Javier

2015-09-01

We characterized multiple knock-out mutants of the four Arabidopsis sucrose phosphate synthase (SPSA1, SPSA2, SPSB and SPSC) isoforms. Despite their reduced SPS activity, spsa1/spsa2, spsa1/spsb, spsa2/spsb, spsa2/spsc, spsb/spsc, spsa1/spsa2/spsb and spsa2/spsb/spsc mutants displayed wild type (WT) vegetative and reproductive morphology, and showed WT photosynthetic capacity and respiration. In contrast, growth of rosettes, flowers and siliques of the spsa1/spsc and spsa1/spsa2/spsc mutants was reduced compared with WT plants. Furthermore, these plants displayed a high dark respiration phenotype. spsa1/spsb/spsc and spsa1/spsa2/spsb/spsc seeds poorly germinated and produced aberrant and sterile plants. Leaves of all viable sps mutants, except spsa1/spsc and spsa1/spsa2/spsc, accumulated WT levels of nonstructural carbohydrates. spsa1/spsc leaves possessed high levels of metabolic intermediates and activities of enzymes of the glycolytic and tricarboxylic acid cycle pathways, and accumulated high levels of metabolic intermediates of the nocturnal starch-to-sucrose conversion process, even under continuous light conditions. Results presented in this work show that SPS is essential for plant viability, reveal redundant functions of the four SPS isoforms in processes that are important for plant growth and nonstructural carbohydrate metabolism, and strongly indicate that accelerated starch turnover and enhanced respiration can alleviate the blockage of sucrose biosynthesis in spsa1/spsc leaves. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Nipbl and mediator cooperatively regulate gene expression to control limb development.

PubMed

Muto, Akihiko; Ikeda, Shingo; Lopez-Burks, Martha E; Kikuchi, Yutaka; Calof, Anne L; Lander, Arthur D; Schilling, Thomas F

2014-09-01

Haploinsufficiency for Nipbl, a cohesin loading protein, causes Cornelia de Lange Syndrome (CdLS), the most common "cohesinopathy". It has been proposed that the effects of Nipbl-haploinsufficiency result from disruption of long-range communication between DNA elements. Here we use zebrafish and mouse models of CdLS to examine how transcriptional changes caused by Nipbl deficiency give rise to limb defects, a common condition in individuals with CdLS. In the zebrafish pectoral fin (forelimb), knockdown of Nipbl expression led to size reductions and patterning defects that were preceded by dysregulated expression of key early limb development genes, including fgfs, shha, hand2 and multiple hox genes. In limb buds of Nipbl-haploinsufficient mice, transcriptome analysis revealed many similar gene expression changes, as well as altered expression of additional classes of genes that play roles in limb development. In both species, the pattern of dysregulation of hox-gene expression depended on genomic location within the Hox clusters. In view of studies suggesting that Nipbl colocalizes with the mediator complex, which facilitates enhancer-promoter communication, we also examined zebrafish deficient for the Med12 Mediator subunit, and found they resembled Nipbl-deficient fish in both morphology and gene expression. Moreover, combined partial reduction of both Nipbl and Med12 had a strongly synergistic effect, consistent with both molecules acting in a common pathway. In addition, three-dimensional fluorescent in situ hybridization revealed that Nipbl and Med12 are required to bring regions containing long-range enhancers into close proximity with the zebrafish hoxda cluster. These data demonstrate a crucial role for Nipbl in limb development, and support the view that its actions on multiple gene pathways result from its influence, together with Mediator, on regulation of long-range chromosomal interactions.

Drowned carbonate platforms in the Huon Gulf, Papua New Guinea

NASA Astrophysics Data System (ADS)

Webster, Jody M.; Wallace, Laura; Silver, Eli; Applegate, Bruce; Potts, Donald; Braga, Juan Carlos; Riker-Coleman, Kristin; Gallup, Christina

2004-11-01

The western Huon Gulf, Papua New Guinea, is an actively subsiding foreland basin dominated by drowned carbonate platforms. We investigated these platforms using new high-resolution multibeam, side-scan sonar and seismic data, combined with submersible observations and previously published radiometric and sedimentary facies data. The data reveal 14 distinct drowned carbonate platforms and numerous pinnacles/banks that increase in age (˜20-450 kyr) and depth (0.1-2.5 km) NE toward the Ramu-Markham Trench. Superimposed on this overall downward flexing of the platforms toward the trench is a systematic tilting of the deep platforms 15 m/km toward the NW and the shallow platforms 2 m/km toward the SE. This may reflect the encroaching thrust load from the NW (Finisterre Range) and spatial variations in the flexural rigidity of the underlying basement. The drowned platforms form a complex system of promontories and reentrants, with abundant pinnacles and banks preserved at similar depths seaward of the main platforms. This configuration closely mimics the present-day Huon coastline and its seaward islands fringed by modern coral reefs. The platforms retain structural, morphologic, and sedimentary facies evidence of primary platform growth, drowning, and subsequent backstepping, despite some lateral erosion of the platform margins (<100 m slope defacement) by mass wasting. Both platforms and pinnacles are composite features containing multiple terrace levels and notches, corresponding to multiple phases of growth, emergence, and drowning in response to rapid climatic and sea level changes during the evolution of each structure. On the basis of all observational and numerical modeling data, we propose a chronology for the initiation, growth, and drowning of the 14 platforms. Over shorter timescales (≤100 kyr) the rate and amplitude of eustatic sea level changes are critical in controlling initiation, growth, drowning or subaerial exposure, subsequent reinitiation, and final drowning of the platforms. However, continued tectonic subsidence and basement substrate morphology influence the overall backstepping geometry and subsequent tilting of the platforms over longer timescales (≥100-500 kyr).

CSI 2264: Simultaneous Optical and Infrared Light Curves of Young Disk-bearing Stars in NGC 2264 with CoRoT and Spitzer—Evidence for Multiple Origins of Variability

NASA Astrophysics Data System (ADS)

Cody, Ann Marie; Stauffer, John; Baglin, Annie; Micela, Giuseppina; Rebull, Luisa M.; Flaccomio, Ettore; Morales-Calderón, María; Aigrain, Suzanne; Bouvier, Jèrôme; Hillenbrand, Lynne A.; Gutermuth, Robert; Song, Inseok; Turner, Neal; Alencar, Silvia H. P.; Zwintz, Konstanze; Plavchan, Peter; Carpenter, John; Findeisen, Krzysztof; Carey, Sean; Terebey, Susan; Hartmann, Lee; Calvet, Nuria; Teixeira, Paula; Vrba, Frederick J.; Wolk, Scott; Covey, Kevin; Poppenhaeger, Katja; Günther, Hans Moritz; Forbrich, Jan; Whitney, Barbara; Affer, Laura; Herbst, William; Hora, Joseph; Barrado, David; Holtzman, Jon; Marchis, Franck; Wood, Kenneth; Medeiros Guimarães, Marcelo; Lillo Box, Jorge; Gillen, Ed; McQuillan, Amy; Espaillat, Catherine; Allen, Lori; D'Alessio, Paola; Favata, Fabio

2014-04-01

We present the Coordinated Synoptic Investigation of NGC 2264, a continuous 30 day multi-wavelength photometric monitoring campaign on more than 1000 young cluster members using 16 telescopes. The unprecedented combination of multi-wavelength, high-precision, high-cadence, and long-duration data opens a new window into the time domain behavior of young stellar objects. Here we provide an overview of the observations, focusing on results from Spitzer and CoRoT. The highlight of this work is detailed analysis of 162 classical T Tauri stars for which we can probe optical and mid-infrared flux variations to 1% amplitudes and sub-hour timescales. We present a morphological variability census and then use metrics of periodicity, stochasticity, and symmetry to statistically separate the light curves into seven distinct classes, which we suggest represent different physical processes and geometric effects. We provide distributions of the characteristic timescales and amplitudes and assess the fractional representation within each class. The largest category (>20%) are optical "dippers" with discrete fading events lasting ~1-5 days. The degree of correlation between the optical and infrared light curves is positive but weak; notably, the independently assigned optical and infrared morphology classes tend to be different for the same object. Assessment of flux variation behavior with respect to (circum)stellar properties reveals correlations of variability parameters with Hα emission and with effective temperature. Overall, our results point to multiple origins of young star variability, including circumstellar obscuration events, hot spots on the star and/or disk, accretion bursts, and rapid structural changes in the inner disk. Based on data from the Spitzer and CoRoT missions. The CoRoT space mission was developed and is operated by the French space agency CNES, with participation of ESA's RSSD and Science Programmes, Austria, Belgium, Brazil, Germany, and Spain.

Resource partitioning facilitates coexistence in sympatric cetaceans in the California Current.

PubMed

Fossette, Sabrina; Abrahms, Briana; Hazen, Elliott L; Bograd, Steven J; Zilliacus, Kelly M; Calambokidis, John; Burrows, Julia A; Goldbogen, Jeremy A; Harvey, James T; Marinovic, Baldo; Tershy, Bernie; Croll, Donald A

2017-11-01

Resource partitioning is an important process driving habitat use and foraging strategies in sympatric species that potentially compete. Differences in foraging behavior are hypothesized to contribute to species coexistence by facilitating resource partitioning, but little is known on the multiple mechanisms for partitioning that may occur simultaneously. Studies are further limited in the marine environment, where the spatial and temporal distribution of resources is highly dynamic and subsequently difficult to quantify. We investigated potential pathways by which foraging behavior may facilitate resource partitioning in two of the largest co-occurring and closely related species on Earth, blue ( Balaenoptera musculus ) and humpback ( Megaptera novaeangliae ) whales. We integrated multiple long-term datasets (line-transect surveys, whale-watching records, net sampling, stable isotope analysis, and remote-sensing of oceanographic parameters) to compare the diet, phenology, and distribution of the two species during their foraging periods in the highly productive waters of Monterey Bay, California, USA within the California Current Ecosystem. Our long-term study reveals that blue and humpback whales likely facilitate sympatry by partitioning their foraging along three axes: trophic, temporal, and spatial. Blue whales were specialists foraging on krill, predictably targeting a seasonal peak in krill abundance, were present in the bay for an average of 4.7 months, and were spatially restricted at the continental shelf break. In contrast, humpback whales were generalists apparently feeding on a mixed diet of krill and fishes depending on relative abundances, were present in the bay for a more extended period (average of 6.6 months), and had a broader spatial distribution at the shelf break and inshore. Ultimately, competition for common resources can lead to behavioral, morphological, and physiological character displacement between sympatric species. Understanding the mechanisms for species coexistence is both fundamental to maintaining biodiverse ecosystems, and provides insight into the evolutionary drivers of morphological differences in closely related species.

­­­­High-Resolution Mapping of Kick`em Jenny Submarine Volcano and Associated Landslides

NASA Astrophysics Data System (ADS)

Ruchala, T. L.; Carey, S.; Hart, L.; Chen, M.; Scott, C.; Tominaga, M.; Dondin, F. J. Y.; Fujii, M.

2016-02-01

To understand the physical and geological processes that drive the volcanism and control the morphology of Kick`em Jenny (KEJ) volcano, the only active submarine volcano in the in the Lesser Antilles volcanic arc, we conducted near-source, high-resolution mapping of KEJ and its subsurface using the Remotely Operated Vehicle (ROV) Hercules during cruise NA054 of the E/V Nautilus (Sept.-Oct. 2014). Shipboard bathymetric data (EM302 system) and slope analysis maps were used to decipher the detailed seafloor morphology surrounding KEJ. Multiple generations of submarine landslides and canyons were observed, suggesting the area has been hosting dynamic sediment transport systems at multiple scales over time. Some of them might have been associated by past eruptions. Clear contacts between partially lithified carbonate sediments and volcanic formations were identified from ROV videos at the middle of the landslide slope face. Detailed observations of facies on these exposures provide constraints on the time intervals between landslide events along the western slope of KEJ. ROV video imagery also identified outcrops of columnar basalts located in the middle of the landslide deposits. These are similar in appearance to those observed in the KEJ crater during previous ROV dives, indicating a possible travel distance of volcanic materials from the crater region along landslide path. High-resolution photo mosaics, bathymetry, and magnetic data acquired by ROV Hercules were used to investigate geological processes and the possible volcanic source of landslide material within the KEJ crater. Mapping in the northwestern part of the crater floor revealed distinctive regions, including (i) microbial mats, (ii) active hydrothermal vent sites; (iii) landforms curved by channelized bottom current where seafloor is outcropped; and (iv) coarse scree the distribution of which may correlate with the distance from the crater rim. Near-bottom magnetic profiles show coherent magnetic signatures with correlatable high amplitude anomalies located in the middle of the KEJ crater.

Physiological and morphological responses of the temperate seagrass Zostera muelleri to multiple stressors: investigating the interactive effects of light and temperature.

PubMed

York, Paul H; Gruber, Renee K; Hill, Ross; Ralph, Peter J; Booth, David J; Macreadie, Peter I

2013-01-01

Understanding how multiple environmental stressors interact to affect seagrass health (measured as morphological and physiological responses) is important for responding to global declines in seagrass populations. We investigated the interactive effects of temperature stress (24, 27, 30 and 32°C) and shading stress (75, 50, 25 and 0% shade treatments) on the seagrass Zostera muelleri over a 3-month period in laboratory mesocosms. Z. muelleri is widely distributed throughout the temperate and tropical waters of south and east coasts of Australia, and is regarded as a regionally significant species. Optimal growth was observed at 27°C, whereas rapid loss of living shoots and leaf mass occurred at 32°C. We found no difference in the concentration of photosynthetic pigments among temperature treatments by the end of the experiment; however, up-regulation of photoprotective pigments was observed at 30°C. Greater levels of shade resulting in high photochemical efficiencies, while elevated irradiance suppressed effective quantum yield (ΔF/FM'). Chlorophyll fluorescence fast induction curves (FIC) revealed that the J step amplitude was significantly higher in the 0% shade treatment after 8 weeks, indicating a closure of PSII reaction centres, which likely contributed to the decline in ΔF/FM' and photoinhibition under higher irradiance. Effective quantum yield of PSII (ΔF/FM') declined steadily in 32°C treatments, indicating thermal damage. Higher temperatures (30°C) resulted in reduced above-ground biomass ratio and smaller leaves, while reduced light led to a reduction in leaf and shoot density, above-ground biomass ratio, shoot biomass and an increase in leaf senescence. Surprisingly, light and temperature had few interactive effects on seagrass health, even though these two stressors had strong effects on seagrass health when tested in isolation. In summary, these results demonstrate that populations of Z. muelleri in south-eastern Australia are sensitive to small chronic temperature increases and light decreases that are predicted under future climate change scenarios.

DEEP CHANDRA X-RAY IMAGING OF A NEARBY RADIO GALAXY 4C+29.30: X-RAY/RADIO CONNECTION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Siemiginowska, Aneta; Aldcroft, Thomas L.; Burke, D. J.

2012-05-10

We report results from our deep Chandra X-ray observations of a nearby radio galaxy, 4C+29.30 (z = 0.0647). The Chandra image resolves structures on sub-arcsec to arcsec scales, revealing complex X-ray morphology and detecting the main radio features: the nucleus, a jet, hotspots, and lobes. The nucleus is absorbed (N{sub H} {approx_equal} 3.95{sup +0.27}{sub -0.33} Multiplication-Sign 10{sup 23} cm{sup -2}) with an unabsorbed luminosity of L{sub 2-10keV} {approx_equal} (5.08 {+-} 0.52) Multiplication-Sign 10{sup 43} erg s{sup -1} characteristic of Type 2 active galactic nuclei. Regions of soft (<2 keV) X-ray emission that trace the hot interstellar medium (ISM) are correlatedmore » with radio structures along the main radio axis, indicating a strong relation between the two. The X-ray emission extends beyond the radio source and correlates with the morphology of optical-line-emitting regions. We measured the ISM temperature in several regions across the galaxy to be kT {approx_equal} 0.5 keV, with slightly higher temperatures (of a few keV) in the center and in the vicinity of the radio hotspots. Assuming that these regions were heated by weak shocks driven by the expanding radio source, we estimated the corresponding Mach number of 1.6 in the southern regions. The thermal pressure of the X-ray-emitting gas in the outermost regions suggests that the hot ISM is slightly underpressured with respect to the cold optical-line-emitting gas and radio-emitting plasma, which both seem to be in a rough pressure equilibrium. We conclude that 4C+29.30 displays a complex view of interactions between the jet-driven radio outflow and host galaxy environment, signaling feedback processes closely associated with the central active nucleus.« less

Biogenic twinned crystals exhibiting unique morphological symmetry

NASA Astrophysics Data System (ADS)

Hirsch, Anna; Gur, Dvir; Palmer, Ben; Addadi, Lia; Leiserowitz, Leslie; Kronik, Leeor

Guanine crystals are widely used in nature as components of multilayer reflectors. Organisms control the size, morphology, and arrangement of these crystals, to obtain a variety of optical ''devices''. The reflection systems found in the lens of the scallop eye and in the copepod cuticle are unique in that the multilayered reflectors are tiled together to form a contiguous packed array. In the former, square crystals are tiled to form a reflecting mirror. In the latter, hexagonal crystals are closely packed to produce brilliant colors. Based on electron diffraction, morphology considerations, and density functional theory, these crystals were shown to possess similar monoclinic crystal symmetry, which we have previously identified as different from that of synthetic anhydrous guanine. However, the crystals are different in that multiple twinning about the {012} and the {011} crystallographic planes results in square and hexagonal morphology, respectively. This is a unique example where controlled twinning is used as a strategy to form a morphology with higher symmetry than that of the underlying crystal, allowing for tilling that facilitates optical functionality.

Morphological and ontogenetic stratification of abyssal and hadal Eurythenes gryllus sensu lato (Amphipoda: Lysianassoidea) from the Peru-Chile Trench

NASA Astrophysics Data System (ADS)

Eustace, Ryan M.; Ritchie, Heather; Kilgallen, Niamh M.; Piertney, Stuart B.; Jamieson, Alan J.

2016-03-01

The globally ubiquitous lysianassoid amphipod, Eurythenes gryllus, has been shown to consist of multiple genetically distinct cryptic taxa, with depth considered a major driver of speciation and morphological divergence. Here we examine morphological variation of E. gryllus sensu lato through a continuous depth distribution that spans from abyssal (3000-6000 m) into hadal depths (>6000 m) in the Peru-Chile Trench (SE Pacific Ocean). Three distinct morphospecies were identified: one was confirmed as being E. magellanicus (4602-5329 m) based on DNA sequence and morphological similarity. The other two morphologically distinct species were named based upon depth of occurrence; Abyssal (4602-6173 m) and Hadal (6173-8074 m). The three Eurythenes morphospecies showed vertical ontogenetic stratification across their bathymetric range, where juveniles were found shallower in their depth range and mature females deeper. Potential ecological and evolutionary drivers that explain the observed patterns of intra and inter-specific structure, such as hydrostatic pressure and topographical isolation, are discussed.

Sonographic evaluation of polycystic ovaries.

PubMed

Zhu, Ruo-Yan; Wong, Yee-Chee; Yong, Eu-Leong

2016-11-01

The morphological features of the ovaries in women with polycystic ovary syndrome (PCOS) have been well described by ultrasound imaging technology. These include enlarged ovary size, multiple small follicles of similar size, increased ovarian stromal volume and echogenicity, peripheral distribution of the follicles, and higher stromal blood flow. Ultrasound identification of the presence of polycystic ovarian morphology (PCOM) has been recognized as a component of PCOS diagnosis. With the advance of ultrasound technology, new definition has been proposed recently. There is, however, a paucity of data for the ovarian morphology in normal and PCOS adolescents. Magnetic resonance imaging has the potential to be an alternative imaging modality for diagnosing PCOM in adolescence. Copyright © 2016. Published by Elsevier Ltd.

Multiple Concentric Cylinder Model (MCCM) user's guide

NASA Technical Reports Server (NTRS)

Williams, Todd O.; Pindera, Marek-Jerzy

1994-01-01

A user's guide for the computer program mccm.f is presented. The program is based on a recently developed solution methodology for the inelastic response of an arbitrarily layered, concentric cylinder assemblage under thermomechanical loading which is used to model the axisymmetric behavior of unidirectional metal matrix composites in the presence of various microstructural details. These details include the layered morphology of certain types of ceramic fibers, as well as multiple fiber/matrix interfacial layers recently proposed as a means of reducing fabrication-induced, and in-service, residual stress. The computer code allows efficient characterization and evaluation of new fibers and/or new coating systems on existing fibers with a minimum of effort, taking into account inelastic and temperature-dependent properties and different morphologies of the fiber and the interfacial region. It also facilitates efficient design of engineered interfaces for unidirectional metal matrix composites.

Microglia Morphological Categorization in a Rat Model of Neuroinflammation by Hierarchical Cluster and Principal Components Analysis.

PubMed

Fernández-Arjona, María Del Mar; Grondona, Jesús M; Granados-Durán, Pablo; Fernández-Llebrez, Pedro; López-Ávalos, María D

2017-01-01

It is known that microglia morphology and function are closely related, but only few studies have objectively described different morphological subtypes. To address this issue, morphological parameters of microglial cells were analyzed in a rat model of aseptic neuroinflammation. After the injection of a single dose of the enzyme neuraminidase (NA) within the lateral ventricle (LV) an acute inflammatory process occurs. Sections from NA-injected animals and sham controls were immunolabeled with the microglial marker IBA1, which highlights ramifications and features of the cell shape. Using images obtained by section scanning, individual microglial cells were sampled from various regions (septofimbrial nucleus, hippocampus and hypothalamus) at different times post-injection (2, 4 and 12 h). Each cell yielded a set of 15 morphological parameters by means of image analysis software. Five initial parameters (including fractal measures) were statistically different in cells from NA-injected rats (most of them IL-1β positive, i.e., M1-state) compared to those from control animals (none of them IL-1β positive, i.e., surveillant state). However, additional multimodal parameters were revealed more suitable for hierarchical cluster analysis (HCA). This method pointed out the classification of microglia population in four clusters. Furthermore, a linear discriminant analysis (LDA) suggested three specific parameters to objectively classify any microglia by a decision tree. In addition, a principal components analysis (PCA) revealed two extra valuable variables that allowed to further classifying microglia in a total of eight sub-clusters or types. The spatio-temporal distribution of these different morphotypes in our rat inflammation model allowed to relate specific morphotypes with microglial activation status and brain location. An objective method for microglia classification based on morphological parameters is proposed. Main points Microglia undergo a quantifiable morphological change upon neuraminidase induced inflammation.Hierarchical cluster and principal components analysis allow morphological classification of microglia.Brain location of microglia is a relevant factor.