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Sample records for aneurisma coronario gigante

  1. Gigantism

    MedlinePlus

    Gigantism; Pituitary giant; Overproduction of growth hormone; Growth hormone - excess production ... The most common cause of too much growth hormone release is a noncancerous (benign) tumor of the ...

  2. Dwarfism and gigantism in historical picture postcards.

    PubMed

    Enderle, A

    1998-05-01

    A collection of 893 historical picture postcards from 1900 to 1935, depicting dwarfs and giants, was analysed from medical and psychosocial viewpoints. In conditions such as 'bird headed dwarfism', achondroplasia, cretinism, so-called Aztecs or pinheads, Grebe chondrodysplasia, and acromegalic gigantism, the disorder could be diagnosed easily. In hypopituitary dwarfism, exact diagnosis was more difficult because of heterogeneity. The most common conditions depicted were pituitary dwarfism and achondroplasia. Most of those with gigantism had pituitary gigantism and acromegaly. Brothers and sisters or parents and their children provided evidence of mendelian inheritance of some of these disorders. The cards suggest that being put on show provided, at least in some cases, social benefits. PMID:9764085

  3. Gigantic Suprapubic Lymphedema: A Case Study

    PubMed Central

    Tanhaeivash, Roozbeh; Franiel, Tobias; Grimm, Marc-Oliver

    2016-01-01

    We present the first case study of idiopathic gigantic suprapubic lymphedema and buried penis treated with puboscrotal reconstruction in a patient with initial extreme obesity after an extensive weight reduction (120 kg). Massive localized lymphedema of the suprapubic region should be differentiated from the scrotal type. Severe lymphedema could not resolve on its own and weight reduction does not seem to be helpful in such cases. PMID:27574599

  4. Gigantic Suprapubic Lymphedema: A Case Study.

    PubMed

    Tanhaeivash, Roozbeh; Franiel, Tobias; Grimm, Marc-Oliver; Horstmann, Marcus

    2016-08-01

    We present the first case study of idiopathic gigantic suprapubic lymphedema and buried penis treated with puboscrotal reconstruction in a patient with initial extreme obesity after an extensive weight reduction (120 kg). Massive localized lymphedema of the suprapubic region should be differentiated from the scrotal type. Severe lymphedema could not resolve on its own and weight reduction does not seem to be helpful in such cases. PMID:27574599

  5. Evolution of Gigantism in Amphiumid Salamanders

    PubMed Central

    Bonett, Ronald M.; Chippindale, Paul T.; Moler, Paul E.; Van Devender, R. Wayne; Wake, David B.

    2009-01-01

    The Amphiumidae contains three species of elongate, permanently aquatic salamanders with four diminutive limbs that append one, two, or three toes. Two of the species, Amphiuma means and A. tridactylum, are among the largest salamanders in the world, reaching lengths of more than one meter, whereas the third species (A. pholeter), extinct amphiumids, and closely related salamander families are relatively small. Amphiuma means and A. tridactylum are widespread species and live in a wide range of lowland aquatic habitats on the Coastal Plain of the southeastern United States, whereas A. pholeter is restricted to very specialized organic muck habitats and is syntopic with A. means. Here we present analyses of sequences of mitochondrial and nuclear loci from across the distribution of the three taxa to assess lineage diversity, relationships, and relative timing of divergence in amphiumid salamanders. In addition we analyze the evolution of gigantism in the clade. Our analyses indicate three lineages that have diverged since the late Miocene, that correspond to the three currently recognized species, but the two gigantic species are not each other's closest relatives. Given that the most closely related salamander families and fossil amphiumids from the Upper Cretaceous and Paleocene are relatively small, our results suggest at least two extreme changes in body size within the Amphuimidae. Gigantic body size either evolved once as the ancestral condition of modern amphiumas, with a subsequent strong size reduction in A. pholeter, or gigantism independently evolved twice in the modern species, A. means and A. tridactylum. These patterns are concordant with differences in habitat breadth and range size among lineages, and have implications for reproductive isolation and diversification of amphiumid salamanders. PMID:19461997

  6. Sotos syndrome: An interesting disorder with gigantism

    PubMed Central

    Nalini, A.; Biswas, Arundhati

    2008-01-01

    We report the case of a 16-year-old boy diagnosed to have Sotos syndrome, with rare association of bilateral primary optic atrophy and epilepsy. He presented with accelerated linear growth, facial gestalt, distinctive facial features, seizures and progressive diminution of vision in both eyes. He had features of gigantism from early childhood. An MRI showed that brain and endocrine functions were normal. This case is of interest, as we have to be aware of this not so rare disorder. In addition to the classic features, there were two unusual associations with Sotos syndrome in the patient. PMID:19893668

  7. Gigantism and Its Implications for the History of Life.

    PubMed

    Vermeij, Geerat J

    2016-01-01

    Gigantism-very large body size-is an ecologically important trait associated with competitive superiority. Although it has been studied in particular cases, the general conditions for the evolution and maintenance of gigantism remain obscure. I compiled sizes and dates for the largest species in 3 terrestrial and 7 marine trophic and habitat categories of animals from throughout the Phanerozoic. The largest species (global giants) in all categories are of post-Paleozoic age. Gigantism at this level appeared tens to hundreds of millions of years after mass extinctions and long after the origins of clades in which it evolved. Marine gigantism correlates with high planktic or seafloor productivity, but on land the correspondence between productivity and gigantism is weak at best. All global giants are aerobically active animals, not gentle giants with low metabolic demands. Oxygen concentration in the atmosphere correlates with gigantism in the Paleozoic but not thereafter, likely because of the elaboration of efficient gas-exchange systems in clades containing giants. Although temperature and habitat size are important in the evolution of very large size in some cases, the most important (and rare) enabling circumstance is a highly developed ecological infrastructure in which essential resources are abundant and effectively recycled and reused, permitting activity levels to increase and setting the stage for gigantic animals to evolve. Gigantism as a hallmark of competitive superiority appears to have lost its luster on land after the Mesozoic in favor of alternative means of achieving dominance, especially including social organization and coordinated food-gathering. PMID:26771527

  8. Analysis of lightning development associated with gigantic jets

    NASA Astrophysics Data System (ADS)

    Lu, G.; Cummer, S. A.; Lyons, W. A.; Krehbiel, P. R.; Li, J.; Beasley, W. H.; Rison, W.; Thomas, R. J.; Edens, H. E.; Stanley, M. A.; MacGorman, D. R.; Van Der Velde, O. A.; Cohen, M.; Lang, T. J.; Rutledge, S. A.

    2011-12-01

    We have examined two negative gigantic jets that occurred sufficiently near a very high-frequency (VHF) lightning mapping network that the associated lightning development is well characterized. Remote sensing of broadband (<1 Hz to 400 kHz) magnetic fields provides extra insights into the charge transfer and detailed sequence of fast discharge events associated with these gigantic jets. In both cases the jet-producing flash began with an upward negative leader that first exaggerated the charge imbalance in the upper part of the storm by dissipating upper positive cloud charge, making conditions more favorable for subsequent negative leaders to emanate from the cloud top and develop into a gigantic jet. Neither flash developed cloud-to-ground strokes, confirming the notion that the major charge transfer during gigantic jets occurred between the cloud and the ionosphere. One of these two jets yielded high-altitude VHF sources above 20 km and up to ~35 km, suggesting that VHF techniques are applicable to detect and track the lower portion of negative jet phenomena. Several gigantic jets observed near Duke University, including one appearing to be of positive polarity, are examined to see if the underlying lightning-gigantic jet correlation as inferred from remote magnetic fields generally fits the picture described above.

  9. Gigantism and Its Implications for the History of Life

    PubMed Central

    Vermeij, Geerat J.

    2016-01-01

    Gigantism—very large body size—is an ecologically important trait associated with competitive superiority. Although it has been studied in particular cases, the general conditions for the evolution and maintenance of gigantism remain obscure. I compiled sizes and dates for the largest species in 3 terrestrial and 7 marine trophic and habitat categories of animals from throughout the Phanerozoic. The largest species (global giants) in all categories are of post-Paleozoic age. Gigantism at this level appeared tens to hundreds of millions of years after mass extinctions and long after the origins of clades in which it evolved. Marine gigantism correlates with high planktic or seafloor productivity, but on land the correspondence between productivity and gigantism is weak at best. All global giants are aerobically active animals, not gentle giants with low metabolic demands. Oxygen concentration in the atmosphere correlates with gigantism in the Paleozoic but not thereafter, likely because of the elaboration of efficient gas-exchange systems in clades containing giants. Although temperature and habitat size are important in the evolution of very large size in some cases, the most important (and rare) enabling circumstance is a highly developed ecological infrastructure in which essential resources are abundant and effectively recycled and reused, permitting activity levels to increase and setting the stage for gigantic animals to evolve. Gigantism as a hallmark of competitive superiority appears to have lost its luster on land after the Mesozoic in favor of alternative means of achieving dominance, especially including social organization and coordinated food-gathering. PMID:26771527

  10. Ependimoma myxopapilar sacro gigante con osteolisis

    PubMed Central

    Ajler, Pablo; Landriel, Federico; Goldschmidt, Ezequiel; Campero, Álvaro; Yampolsky, Claudio

    2014-01-01

    Objetivo: la presentación de un caso de una paciente con un ependimoma sacro con extensa infiltración y destrucción ósea local. Descripción del caso: una mujer de 53 años acudió a la consulta por dolor lumbosacro y alteraciones sensitivas perineales y esfinterianas. La imágenes por Resonancia Magnética (IRM) y la Tomografía Axial Computada (TAC) mostraron una lesión expansiva gigante a nivel S2-S4 con extensa osteólisis e invasión de tejidos adyacentes. Se realizó una exéresis tumoral completa con mejoría del estatus funcional. La anatomía patológica informó ependimoma mixopapilar. Discusión: la extensión de la resección quirúrgica es el mejor predictor de buen pronóstico. El tratamiento radiante se reserva como opción adyuvante para las resecciones incompletas y recidiva tumoral. La quimioterapia sólo debería utilizarse en casos en que la cirugía y la radioterapia estén contraindicadas. Conclusión: Los ependimomas mixopapilares sacros con destrucción ósea y presentación intra y extradural son muy infrecuentes y deben ser tenidos en cuenta entre los diagnósticos diferenciales preoperatorios. Su resección total, siempre que sea posible, es la mejor alternativa terapéutica. PMID:25165615

  11. Macrodystrophia Lipomatosa: An Unusual Cause of Localized Gigantism

    PubMed Central

    Maheswari, S Uma; Sampath, V; Ramesh, A; Manoharan, K

    2016-01-01

    Macrodystrophia lipomatosa (MDL) is a rare congenital form of localized gigantism characterized by progressive overgrowth of all mesenchymal elements with a disproportionate increase in fibro adipose tissue. Here we report a case of 20 years old male who presented with history of painless gradual enlargement of entire left upper limb since childhood. Magnetic resonance imaging and histopathology confirmed the diagnosis of macrodystrophia lipomatosa. This condition has to be differentiated from other causes of localized gigantism, since these conditions differ in their course, prognosis, complications and treatment. PMID:27293271

  12. First observations of Gigantic Jets from Monsoon Thunderstorms over India

    NASA Astrophysics Data System (ADS)

    Singh, Rajesh; Maurya, Ajeet; Chanrion, Olivier; Neubert, Torsten; Cummer, Steven; Mlynarczyk, Janusz; Bór, József; Siingh, Devendraa; Cohen, Morris; Kumar, Sushil

    2016-04-01

    Gigantic Jets are electric discharges from thunderstorm cloud tops to the bottom of the ionosphere at ~80 km altitude. After their first discovery in 2001, relatively few observations have been reported. Most of these are from satellites at large distances and a few tens from the ground at higher spatial resolution. Here we report the first Gigantic Jets observed in India from two thunderstorm systems that developed over the land surface from monsoon activity, each storm producing two Gigantic Jets. The jets were recorded by a video camera system at standard video rate (20 ms exposure) at a few hundred km distance. ELF measurements suggest that the jets are of the usual negative polarity and that they develop in less than 40 ms, which is faster than most jets reported in the past. The jets originate from the leading edge of a slowly drifting convective cloud complex close to the highest regions of the clouds and carry ~25 Coulomb of charge to the ionosphere. One jet has a markedly horizontal displacement that we suggest is caused by a combination of close-range cloud electric fields at inception, and longer-range cloud fields at larger distances during full development. The Gigantic Jets are amongst the few that have been observed over land.

  13. Twin Explosions In Gigantic Dusty Potato Crisp

    NASA Astrophysics Data System (ADS)

    2006-05-01

    ESO's Very Large Telescope, equipped with the multi-mode FORS instrument, took an image of NGC 3190, a galaxy so distorted that astronomers gave it two names. And as if to prove them right, in 2002 it fired off, almost simultaneously, two stellar explosions, a very rare event. This beautiful edge-on spiral galaxy with tightly wound arms and a warped shape that makes it resemble a gigantic potato crisp lies in the constellation Leo ('the Lion') [1] and is approximately 70 million light years away. It is the dominant member of a small group of galaxies known as Hickson 44, named after the Canadian astronomer, Paul Hickson. In addition to NGC 3190 [2], Hickson 44 consists of one elliptical and two spiral galaxies. These are, however, slightly out of the field of view and therefore not visible here. ESO PR Photo 17/06 ESO PR Photo 17/06 The Spiral Galaxy NGC 3190 In 1982, Hickson published a catalogue of over 400 galaxies found in compact, physically-related groups of typically 4 to 5 galaxies per group (see the image of Robert's Quartet in ESO PR Photo 34/05 as another example). Such compact groups allow astronomers to study how galaxies dynamically affect each other, and help them test current ideas on how galaxies form. One idea is that compact groups of galaxies, such as Hickson 44, merge to form a giant elliptical galaxy, such as NGC 1316 (see ESO PR 17/00). Indeed, signs of tidal interactions are visible in the twisted dust lane of NGC 3190. This distortion initially misled astronomers into assigning a separate name for the southwestern side, NGC 3189, although NGC 3190 is the favoured designation. NGC 3190 has an 'Active Galactic Nucleus', and as such, the bright, compact nucleus is thought to host a supermassive black hole. In March 2002, a new supernova (SN 2002bo) was found in between the 'V' of the dust lanes in the southeastern part of NGC 3190. It was discovered independently by the Brazilian and Japanese amateur astronomers, Paulo Cacella and Yoji Hirose

  14. Hereditary Gigantism-the biblical giant Goliath and his brothers.

    PubMed

    Donnelly, Deirdre E; Morrison, Patrick J

    2014-05-01

    The biblical giant Goliath has an identifiable family tree suggestive of autosomal dominant inheritance. We suggest that he had a hereditary pituitary disorder possibly due to the AIP gene, causing early onset and familial acromegaly or gigantism. We comment on the evidence within the scriptures for his other relatives including a relative with six digits and speculate on possible causes of the six digits. Recognition of a hereditary pituitary disorder in the biblical Goliath and his family sheds additional information on his and other family members' battles with David and his relatives. PMID:25075136

  15. Proteus syndrome: A rare cause of gigantic limb

    PubMed Central

    Chakrabarti, Nandini; Chattopadhyay, Chandan; Bhuban, Majhi; Pal, Salil Kumar

    2014-01-01

    A congenital disorder with variable manifestations, including partial gigantism of the hands and feet with hypertrophy of soles, nevi, hemihypertrophy, gynecomastia, macrocephaly and other skull abnormalities, and abdominal lipomatosis. The cause is unknown, although a genetic origin, generally of autosomal-dominant transmission, has been conjectured. Symptoms can be treated, but there is no known cure. We present the case of a young male with grotesque overgrowth of the right lower limb, splenomegaly and multiple nevi. Angiography revealed venous malformation within the limb. The findings are in conformity to the criteria for the Proteus syndrome. PMID:24860761

  16. Gigantic jets between a thundercloud and the ionosphere.

    PubMed

    Su, H T; Hsu, R R; Chen, A B; Wang, Y C; Hsiao, W S; Lai, W C; Lee, L C; Sato, M; Fukunishi, H

    2003-06-26

    Transient luminous events in the atmosphere, such as lighting-induced sprites and upwardly discharging blue jets, were discovered recently in the region between thunderclouds and the ionosphere. In the conventional picture, the main components of Earth's global electric circuit include thunderstorms, the conducting ionosphere, the downward fair-weather currents and the conducting Earth. Thunderstorms serve as one of the generators that drive current upward from cloud tops to the ionosphere, where the electric potential is hundreds of kilovolts higher than Earth's surface. It has not been clear, however, whether all the important components of the global circuit have even been identified. Here we report observations of five gigantic jets that establish a direct link between a thundercloud (altitude approximately 16 km) and the ionosphere at 90 km elevation. Extremely-low-frequency radio waves in four events were detected, while no cloud-to-ground lightning was observed to trigger these events. Our result indicates that the extremely-low-frequency waves were generated by negative cloud-to-ionosphere discharges, which would reduce the electrical potential between ionosphere and ground. Therefore, the conventional picture of the global electric circuit needs to be modified to include the contributions of gigantic jets and possibly sprites. PMID:12827198

  17. Gigantic enhancement of spin Seebeck effect by phonon drag

    NASA Astrophysics Data System (ADS)

    Adachi, Hiroto; Uchida, Ken-Ichi; Saitoh, Eiji; Ohe, Jun-Ichiro; Takahashi, Saburo; Maekawa, Sadamichi

    2011-03-01

    We investigate both theoretically and experimentally a gigantic enhancement of the spin Seebeck effect [K. Uchida et al., Nature 455, 778 (2008); C. M. Jaworski et al., Nature Mater. 9, 898 (2010); K. Uchida et al., Nature Mater. 9, 894 (2010)] in a prototypical magnet La Y2 Fe 5 O12 at low temperatures. Our theoretical analysis sheds light on the important role of phonons; the spin Seebeck effect is enormously enhanced by nonequilibrium phonons that drag the low-lying spin excitations. We further argue that this scenario gives a clue to understand the observation of the spin Seebeck effect that is unaccompanied by a global spin current, and predict that the substrate condition affects the observed signal.

  18. Methodology of growing gigantic sapphire for GSLW project

    NASA Astrophysics Data System (ADS)

    Abgaryan, Artoush A.; Hartounian, Gomidas

    2005-09-01

    In our present world the Crystal Growth Technology does not have the necessary and sufficient conditions to manufacture large sizes; especially in the Sapphire Crystal world. We have a theoretical and methodological development for growing gigantic Sapphire Crystal Lenses. Our gigantic Sapphire Crystal Lenses have a unique optical characteristic which will be used in the Global System of Laser Weapons (GSLW); hence solving one of the crucial problems in the Relay Mirror System; where it captures the Laser beam from the earth surface, cleaning the beam in the Satellite and redirecting the laser energy to the precise desired target. Developed and solution for the temperature and heat-elasticity fields in growth systems are considered theoretical, in order to assess their effects on the optical symmetry of the growing crystal. The process is modeled using three-dimensional curvilinear coordinates to describe a closed, low-strain heat-elasticity system, with allowance made for the temperature variations of the thermal properties of the multilayer growth system, and nonlinear and unsteady-state process with arbitrary boundary conditions. The results presented as plots of the strain, stress, displacement, and temperature fields; demonstrate the potential of the method for designing new growth units and improving the existing ones and suggesting that crystals, in general, without frustration of optical symmetry can, in principle, be grown. In order to solve generalized problem for large optics. It is required to have super and correct mathematical computing calculations, and using basic fundamental laws of nature regarding optical symmetry in the crystal, and discovering the radical "new wave method" for crystal growth technology.

  19. Gigantic surface lifetime of an intrinsic topological insulator.

    PubMed

    Neupane, Madhab; Xu, Su-Yang; Ishida, Yukiaki; Jia, Shuang; Fregoso, Benjamin M; Liu, Chang; Belopolski, Ilya; Bian, Guang; Alidoust, Nasser; Durakiewicz, Tomasz; Galitski, Victor; Shin, Shik; Cava, Robert J; Hasan, M Zahid

    2015-09-11

    The interaction between light and novel two-dimensional electronic states holds promise to realize new fundamental physics and optical devices. Here, we use pump-probe photoemission spectroscopy to study the optically excited Dirac surface states in the bulk-insulating topological insulator Bi_{2}Te_{2}Se and reveal optical properties that are in sharp contrast to those of bulk-metallic topological insulators. We observe a gigantic optical lifetime exceeding 4  μs (1  μs=10^{-6}  s) for the surface states in Bi_{2}Te_{2}Se, whereas the lifetime in most topological insulators, such as Bi_{2}Se_{3}, has been limited to a few picoseconds (1  ps=10^{-12}  s). Moreover, we discover a surface photovoltage, a shift of the chemical potential of the Dirac surface states, as large as 100 mV. Our results demonstrate a rare platform to study charge excitation and relaxation in energy and momentum space in a two-dimensional system. PMID:26406846

  20. Atmospheric oxygen and the evolution of insect gigantism

    NASA Astrophysics Data System (ADS)

    Dudley, R.

    2003-04-01

    Geophysical analyses suggest the presence of a late Paleozoic oxygen pulse beginning in the late Devonian and continuing through to the late Carboniferous. During this time, atmospheric oxygen levels increased to values potentially as high as 35% relative to the contemporary value of 21%. Widespread gigantism in late Paleozoic insects and other arthropods is consistent with enhanced oxygen flux within diffusion-limited tracheal systems, and thus with relaxation of constraints on maximum insect body size. Because total atmospheric pressure increases with increased oxygen partial pressure, concurrently hyperdense conditions would have augmented aerodynamic force production in early forms of flying insects. Hyperoxia of the late Paleozoic atmosphere may also have physiologically facilitated the initial evolution of insect flight metabolism. By the late Permian, evolution of decompositional microbial and fungal communities together with disequilibrium in rates of carbon deposition gradually reduced oxygen concentrations to values possibly as low as 15%. The disappearance of giant insects by the end of the Permian is consistent with extinction of these taxa for reasons of asphyxiation on a geological time scale. In modern selection experiments with Drosophila flies, substantial plasticity in body size can be evoked under conditions of variable oxygen. In particular, moderate hyperbaria (and thus hyperoxia) evokes a 20% increase in adult body size over merely five generations, suggesting ready capacity for evolutionary responses by insects to fluctuating atmospheric oxygen.

  1. LTR Retrotransposons Contribute to Genomic Gigantism in Plethodontid Salamanders

    PubMed Central

    Sun, Cheng; Shepard, Donald B.; Chong, Rebecca A.; López Arriaza, José; Hall, Kathryn; Castoe, Todd A.; Feschotte, Cédric; Pollock, David D.; Mueller, Rachel Lockridge

    2012-01-01

    Among vertebrates, most of the largest genomes are found within the salamanders, a clade of amphibians that includes 613 species. Salamander genome sizes range from ∼14 to ∼120 Gb. Because genome size is correlated with nucleus and cell sizes, as well as other traits, morphological evolution in salamanders has been profoundly affected by genomic gigantism. However, the molecular mechanisms driving genomic expansion in this clade remain largely unknown. Here, we present the first comparative analysis of transposable element (TE) content in salamanders. Using high-throughput sequencing, we generated genomic shotgun data for six species from the Plethodontidae, the largest family of salamanders. We then developed a pipeline to mine TE sequences from shotgun data in taxa with limited genomic resources, such as salamanders. Our summaries of overall TE abundance and diversity for each species demonstrate that TEs make up a substantial portion of salamander genomes, and that all of the major known types of TEs are represented in salamanders. The most abundant TE superfamilies found in the genomes of our six focal species are similar, despite substantial variation in genome size. However, our results demonstrate a major difference between salamanders and other vertebrates: salamander genomes contain much larger amounts of long terminal repeat (LTR) retrotransposons, primarily Ty3/gypsy elements. Thus, the extreme increase in genome size that occurred in salamanders was likely accompanied by a shift in TE landscape. These results suggest that increased proliferation of LTR retrotransposons was a major molecular mechanism contributing to genomic expansion in salamanders. PMID:22200636

  2. Gigantism and comparative life-history parameters of tyrannosaurid dinosaurs.

    PubMed

    Erickson, Gregory M; Makovicky, Peter J; Currie, Philip J; Norell, Mark A; Yerby, Scott A; Brochu, Christopher A

    2004-08-12

    How evolutionary changes in body size are brought about by variance in developmental timing and/or growth rates (also known as heterochrony) is a topic of considerable interest in evolutionary biology. In particular, extreme size change leading to gigantism occurred within the dinosaurs on multiple occasions. Whether this change was brought about by accelerated growth, delayed maturity or a combination of both processes is unknown. A better understanding of relationships between non-avian dinosaur groups and the newfound capacity to reconstruct their growth curves make it possible to address these questions quantitatively. Here we study growth patterns within the Tyrannosauridae, the best known group of large carnivorous dinosaurs, and determine the developmental means by which Tyrannosaurus rex, weighing 5,000 kg and more, grew to be one of the most enormous terrestrial carnivorous animals ever. T. rex had a maximal growth rate of 2.1 kg d(-1), reached skeletal maturity in two decades and lived for up to 28 years. T. rex's great stature was primarily attained by accelerating growth rates beyond that of its closest relatives. PMID:15306807

  3. Biology of the sauropod dinosaurs: the evolution of gigantism

    PubMed Central

    Sander, P Martin; Christian, Andreas; Clauss, Marcus; Fechner, Regina; Gee, Carole T; Griebeler, Eva-Maria; Gunga, Hanns-Christian; Hummel, Jürgen; Mallison, Heinrich; Perry, Steven F; Preuschoft, Holger; Rauhut, Oliver W M; Remes, Kristian; Tütken, Thomas; Wings, Oliver; Witzel, Ulrich

    2011-01-01

    The herbivorous sauropod dinosaurs of the Jurassic and Cretaceous periods were the largest terrestrial animals ever, surpassing the largest herbivorous mammals by an order of magnitude in body mass. Several evolutionary lineages among Sauropoda produced giants with body masses in excess of 50 metric tonnes by conservative estimates. With body mass increase driven by the selective advantages of large body size, animal lineages will increase in body size until they reach the limit determined by the interplay of bauplan, biology, and resource availability. There is no evidence, however, that resource availability and global physicochemical parameters were different enough in the Mesozoic to have led to sauropod gigantism. We review the biology of sauropod dinosaurs in detail and posit that sauropod gigantism was made possible by a specific combination of plesiomorphic characters (phylogenetic heritage) and evolutionary innovations at different levels which triggered a remarkable evolutionary cascade. Of these key innovations, the most important probably was the very long neck, the most conspicuous feature of the sauropod bauplan. Compared to other herbivores, the long neck allowed more efficient food uptake than in other large herbivores by covering a much larger feeding envelope and making food accessible that was out of the reach of other herbivores. Sauropods thus must have been able to take up more energy from their environment than other herbivores. The long neck, in turn, could only evolve because of the small head and the extensive pneumatization of the sauropod axial skeleton, lightening the neck. The small head was possible because food was ingested without mastication. Both mastication and a gastric mill would have limited food uptake rate. Scaling relationships between gastrointestinal tract size and basal metabolic rate (BMR) suggest that sauropods compensated for the lack of particle reduction with long retention times, even at high uptake rates. The

  4. Genomic gigantism: DNA loss is slow in mountain grasshoppers.

    PubMed

    Bensasson, D; Petrov, D A; Zhang, D X; Hartl, D L; Hewitt, G M

    2001-02-01

    Several studies have shown DNA loss to be inversely correlated with genome size in animals. These studies include a comparison between Drosophila and the cricket, Laupala, but there has been no assessment of DNA loss in insects with very large genomes. Podisma pedestris, the brown mountain grasshopper, has a genome over 100 times as large as that of Drosophila and 10 times as large as that of Laupala. We used 58 paralogous nuclear pseudogenes of mitochondrial origin to study the characteristics of insertion, deletion, and point substitution in P. pedestris and Italopodisma. In animals, these pseudogenes are "dead on arrival"; they are abundant in many different eukaryotes, and their mitochondrial origin simplifies the identification of point substitutions accumulated in nuclear pseudogene lineages. There appears to be a mononucleotide repeat within the 643-bp pseudogene sequence studied that acts as a strong hot spot for insertions or deletions (indels). Because the data for other insect species did not contain such an unusual region, hot spots were excluded from species comparisons. The rate of DNA loss relative to point substitution appears to be considerably and significantly lower in the grasshoppers studied than in Drosophila or Laupala. This suggests that the inverse correlation between genome size and the rate of DNA loss can be extended to comparisons between insects with large or gigantic genomes (i.e., Laupala and Podisma). The low rate of DNA loss implies that in grasshoppers, the accumulation of point mutations is a more potent force for obscuring ancient pseudogenes than their loss through indel accumulation, whereas the reverse is true for Drosophila. The main factor contributing to the difference in the rates of DNA loss estimated for grasshoppers, crickets, and Drosophila appears to be deletion size. Large deletions are relatively rare in Podisma and Italopodisma. PMID:11158383

  5. Gigantism and Acromegaly Due to Xq26 Microduplications and GPR101 Mutation

    PubMed Central

    Trivellin, G.; Daly, A.F.; Faucz, F.R.; Yuan, B.; Rostomyan, L.; Larco, D.O.; Schernthaner-Reiter, M.H.; Szarek, E.; Leal, L.F.; Caberg, J.-H.; Castermans, E.; Villa, C.; Dimopoulos, A.; Chittiboina, P.; Xekouki, P.; Shah, N.; Metzger, D.; Lysy, P.A.; Ferrante, E.; Strebkova, N.; Mazerkina, N.; Zatelli, M.C.; Lodish, M.; Horvath, A.; de Alexandre, R. Bertollo; Manning, A.D.; Levy, I.; Keil, M.F.; de la Luz Sierra, M.; Palmeira, L.; Coppieters, W.; Georges, M.; Naves, L.A.; Jamar, M.; Bours, V.; Wu, T.J.; Choong, C.S.; Bertherat, J.; Chanson, P.; Kamenický, P.; Farrell, W.E.; Barlier, A.; Quezado, M.; Bjelobaba, I.; Stojilkovic, S.S.; Wess, J.; Costanzi, S.; Liu, P.; Lupski, J.R.; Beckers, A.; Stratakis, C.A.

    2015-01-01

    BACKGROUND Increased secretion of growth hormone leads to gigantism in children and acromegaly in adults; the genetic causes of gigantism and acromegaly are poorly understood. METHODS We performed clinical and genetic studies of samples obtained from 43 patients with gigantism and then sequenced an implicated gene in samples from 248 patients with acromegaly. RESULTS We observed microduplication on chromosome Xq26.3 in samples from 13 patients with gigantism; of these samples, 4 were obtained from members of two unrelated kindreds, and 9 were from patients with sporadic cases. All the patients had disease onset during early childhood. Of the patients with gigantism who did not carry an Xq26.3 microduplication, none presented before the age of 5 years. Genomic characterization of the Xq26.3 region suggests that the microduplications are generated during chromosome replication and that they contain four protein-coding genes. Only one of these genes, GPR101, which encodes a G-protein–coupled receptor, was overexpressed in patients’ pituitary lesions. We identified a recurrent GPR101 mutation (p.E308D) in 11 of 248 patients with acromegaly, with the mutation found mostly in tumors. When the mutation was transfected into rat GH3 cells, it led to increased release of growth hormone and proliferation of growth hormone–producing cells. CONCLUSIONS We describe a pediatric disorder (which we have termed X-linked acrogigantism [X-LAG]) that is caused by an Xq26.3 genomic duplication and is characterized by early-onset gigantism resulting from an excess of growth hormone. Duplication of GPR101 probably causes X-LAG. We also found a recurrent mutation in GPR101 in some adults with acromegaly. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and others.) PMID:25470569

  6. An Evolutionary Cascade Model for Sauropod Dinosaur Gigantism - Overview, Update and Tests

    PubMed Central

    Sander, P. Martin

    2013-01-01

    Sauropod dinosaurs are a group of herbivorous dinosaurs which exceeded all other terrestrial vertebrates in mean and maximal body size. Sauropod dinosaurs were also the most successful and long-lived herbivorous tetrapod clade, but no abiological factors such as global environmental parameters conducive to their gigantism can be identified. These facts justify major efforts by evolutionary biologists and paleontologists to understand sauropods as living animals and to explain their evolutionary success and uniquely gigantic body size. Contributions to this research program have come from many fields and can be synthesized into a biological evolutionary cascade model of sauropod dinosaur gigantism (sauropod gigantism ECM). This review focuses on the sauropod gigantism ECM, providing an updated version based on the contributions to the PLoS ONE sauropod gigantism collection and on other very recent published evidence. The model consist of five separate evolutionary cascades (“Reproduction”, “Feeding”, “Head and neck”, “Avian-style lung”, and “Metabolism”). Each cascade starts with observed or inferred basal traits that either may be plesiomorphic or derived at the level of Sauropoda. Each trait confers hypothetical selective advantages which permit the evolution of the next trait. Feedback loops in the ECM consist of selective advantages originating from traits higher in the cascades but affecting lower traits. All cascades end in the trait “Very high body mass”. Each cascade is linked to at least one other cascade. Important plesiomorphic traits of sauropod dinosaurs that entered the model were ovipary as well as no mastication of food. Important evolutionary innovations (derived traits) were an avian-style respiratory system and an elevated basal metabolic rate. Comparison with other tetrapod lineages identifies factors limiting body size. PMID:24205267

  7. Gigantic self-confined pahoehoe inflated lava flows in Argentina

    NASA Astrophysics Data System (ADS)

    Pasquare', G.; Bistacchi, A.

    2007-05-01

    The largest lava flows on Earth are pahoehoe basalts emplaced by inflation, a process which can change lava lobes initially a few decimetres thick into large lava sheets several metres thick. Inflation involves the initial formation of a thin, solidified, viscoelastic crust, under which liquid lava is continually added. This thermally efficient endogenous growth process explains the spread of huge volumes of lava over large, almost flat areas, as in the sheet flows which characterise the distal portions of Hawaiian volcanoes or some continental flood basalt provinces. Long, narrow, inflated pahoehoe flows have occasionally been described, either emplaced along pre-existing river channels or confined within topographic barriers. In this contribution we present previously unknown inflated pahoehoe lava flows following very long, narrow pathways over an almost flat surface, with no topographic confinement. Lava, which erupted in Late Quaternary times from the eastern tip of a 60 km long volcanic fissure in Argentina, formed several discrete flows extending as far as 180 km from the source. This fissure was characterized by a long-lasting and complex activity. Alkali-basaltic lava flows were emitted at the two extremities of the fissure system. In the intermediate section of the fissure, the Payun Matru, a great trachitic composite volcano, developed, giving rise to a large caldera which produced large pyroclastic flows. Alkali-basalts predate and postdate the trachitic activity, in fact at the end of the trachitic activity, new basaltic lava flows (mainly aa) were emitted from both ends of the fissure. We studied in details the youngest of the gigantic flows (Pampas Onduladas lava flow), which progressively develops through differing thermally-efficient flow mechanisms. The flow created a large shield volcanic structure at the eastern tip of the E-W fissure and spread to the E forming a very large and thick inflated pahoehoe sheet flow. Leaving the flanks of the

  8. Discharge processes, electric field, and electron energy in ISUAL-recorded gigantic jets

    NASA Astrophysics Data System (ADS)

    Kuo, Cheng-Ling; Chou, J. K.; Tsai, L. Y.; Chen, A. B.; Su, H. T.; Hsu, R. R.; Cummer, S. A.; Frey, H. U.; Mende, S. B.; Takahashi, Y.; Lee, L. C.

    2009-04-01

    This article reports the first high time resolution measurements of gigantic jets from the Imager of Sprites and Upper Atmospheric Lightning (ISUAL) experiment. The velocity of the upward propagating fully developed jet stage of the gigantic jets was ˜107 m s-1, which is similar to that observed for downward sprite streamers. Analysis of spectral ratios for the fully developed jet emissions gives a reduced E field of 400-655 Td and average electron energy of 8.5-12.3 eV. These values are higher than those in the sprites but are similar to those predicted by streamer models, which implies the existence of streamer tips in fully developed jets. The gigantic jets studied here all contained two distinct photometric peaks. The first peak is from the fully developed jet, which steadily propagates from the cloud top (˜20 km) to the lower ionosphere at ˜90 km. We suggest that the second photometric peak, which occurs ˜1 ms after the first peak, is from a current wave or potential wave-enhanced emissions that originate at an altitude of ˜50 km and extend toward the cloud top. We propose that the fully developed jet serves as an extension of the local ionosphere and produces a lowered ionosphere boundary. As the attachment processes remove the charges, the boundary of the local ionosphere moves up. The current in the channel persists and its contact point with the ionosphere moves upward, which produces the upward surging trailing jets. Imager and photometer data indicate that the lightning activity associated with the gigantic jets likely is in-cloud, and thus the initiation of the gigantic jets is not directly associated with cloud-to-ground discharges.

  9. Gigantic Cosmic Corkscrew Reveals New Details About Mysterious Microquasar

    NASA Astrophysics Data System (ADS)

    2004-10-01

    Making an extra effort to image a faint, gigantic corkscrew traced by fast protons and electrons shot out from a mysterious microquasar paid off for a pair of astrophysicists who gained new insights into the beast's inner workings and also resolved a longstanding dispute over the object's distance. Microquasar SS 433 VLA Image of Microquasar SS 433 CREDIT: Blundell & Bowler, NRAO/AUI/NSF (Click on Image for Larger Version) The astrophysicists used the National Science Foundation's Very Large Array (VLA) radio telescope to capture the faintest details yet seen in the plasma jets emerging from the microquasar SS 433, an object once dubbed the "enigma of the century." As a result, they have changed scientists' understanding of the jets and settled the controversy over its distance "beyond all reasonable doubt," they said. SS 433 is a neutron star or black hole orbited by a "normal" companion star. The powerful gravity of the neutron star or black hole draws material from the stellar wind of its companion into an accretion disk of material tightly circling the dense central object prior to being pulled onto it. This disk propels jets of fast protons and electrons outward from its poles at about a quarter of the speed of light. The disk in SS 433 wobbles like a child's top, causing its jets to trace a corkscrew in the sky every 162 days. The new VLA study indicates that the speed of the ejected particles varies over time, contrary to the traditional model for SS 433. "We found that the actual speed varies between 24 percent to 28 percent of light speed, as opposed to staying constant," said Katherine Blundell, of the University of Oxford in the United Kingdom. "Amazingly, the jets going in both directions change their speeds simultaneously, producing identical speeds in both directions at any given time," Blundell added. Blundell worked with Michael Bowler, also of Oxford. The scientists' findings have been accepted by the Astrophysical Journal Letters. SS 433 New VLA

  10. A gigantic nothosaur (Reptilia: Sauropterygia) from the Middle Triassic of SW China and its implication for the Triassic biotic recovery

    NASA Astrophysics Data System (ADS)

    Liu, Jun; Hu, Shi-Xue; Rieppel, Olivier; Jiang, Da-Yong; Benton, Michael J.; Kelley, Neil P.; Aitchison, Jonathan C.; Zhou, Chang-Yong; Wen, Wen; Huang, Jin-Yuan; Xie, Tao; Lv, Tao

    2014-11-01

    The presence of gigantic apex predators in the eastern Panthalassic and western Tethyan oceans suggests that complex ecosystems in the sea had become re-established in these regions at least by the early Middle Triassic, after the Permian-Triassic mass extinction (PTME). However, it is not clear whether oceanic ecosystem recovery from the PTME was globally synchronous because of the apparent lack of such predators in the eastern Tethyan/western Panthalassic region prior to the Late Triassic. Here we report a gigantic nothosaur from the lower Middle Triassic of Luoping in southwest China (eastern Tethyan ocean), which possesses the largest known lower jaw among Triassic sauropterygians. Phylogenetic analysis suggests parallel evolution of gigantism in Triassic sauropterygians. Discovery of this gigantic apex predator, together with associated diverse marine reptiles and the complex food web, indicates global recovery of shallow marine ecosystems from PTME by the early Middle Triassic.

  11. A gigantic nothosaur (Reptilia: Sauropterygia) from the Middle Triassic of SW China and its implication for the Triassic biotic recovery.

    PubMed

    Liu, Jun; Hu, Shi-Xue; Rieppel, Olivier; Jiang, Da-Yong; Benton, Michael J; Kelley, Neil P; Aitchison, Jonathan C; Zhou, Chang-Yong; Wen, Wen; Huang, Jin-Yuan; Xie, Tao; Lv, Tao

    2014-01-01

    The presence of gigantic apex predators in the eastern Panthalassic and western Tethyan oceans suggests that complex ecosystems in the sea had become re-established in these regions at least by the early Middle Triassic, after the Permian-Triassic mass extinction (PTME). However, it is not clear whether oceanic ecosystem recovery from the PTME was globally synchronous because of the apparent lack of such predators in the eastern Tethyan/western Panthalassic region prior to the Late Triassic. Here we report a gigantic nothosaur from the lower Middle Triassic of Luoping in southwest China (eastern Tethyan ocean), which possesses the largest known lower jaw among Triassic sauropterygians. Phylogenetic analysis suggests parallel evolution of gigantism in Triassic sauropterygians. Discovery of this gigantic apex predator, together with associated diverse marine reptiles and the complex food web, indicates global recovery of shallow marine ecosystems from PTME by the early Middle Triassic. PMID:25429609

  12. A gigantic nothosaur (Reptilia: Sauropterygia) from the Middle Triassic of SW China and its implication for the Triassic biotic recovery

    PubMed Central

    Liu, Jun; Hu, Shi-xue; Rieppel, Olivier; Jiang, Da-yong; Benton, Michael J.; Kelley, Neil P.; Aitchison, Jonathan C.; Zhou, Chang-yong; Wen, Wen; Huang, Jin-yuan; Xie, Tao; Lv, Tao

    2014-01-01

    The presence of gigantic apex predators in the eastern Panthalassic and western Tethyan oceans suggests that complex ecosystems in the sea had become re-established in these regions at least by the early Middle Triassic, after the Permian-Triassic mass extinction (PTME). However, it is not clear whether oceanic ecosystem recovery from the PTME was globally synchronous because of the apparent lack of such predators in the eastern Tethyan/western Panthalassic region prior to the Late Triassic. Here we report a gigantic nothosaur from the lower Middle Triassic of Luoping in southwest China (eastern Tethyan ocean), which possesses the largest known lower jaw among Triassic sauropterygians. Phylogenetic analysis suggests parallel evolution of gigantism in Triassic sauropterygians. Discovery of this gigantic apex predator, together with associated diverse marine reptiles and the complex food web, indicates global recovery of shallow marine ecosystems from PTME by the early Middle Triassic. PMID:25429609

  13. Cope's Rule and Romer's theory: patterns of diversity and gigantism in eurypterids and Palaeozoic vertebrates

    PubMed Central

    Lamsdell, James C.; Braddy, Simon J.

    2010-01-01

    Gigantism is widespread among Palaeozoic arthropods, yet causal mechanisms, particularly the role of (abiotic) environmental factors versus (biotic) competition, remain unknown. The eurypterids (Arthropoda: Chelicerata) include the largest arthropods; gigantic predatory pterygotids (Eurypterina) during the Siluro-Devonian and bizarre sweep-feeding hibbertopterids (Stylonurina) from the Carboniferous to end-Permian. Analysis of family-level originations and extinctions among eurypterids and Palaeozoic vertebrates show that the diversity of Eurypterina waned during the Devonian, while the Placodermi radiated, yet Stylonurina remained relatively unaffected; adopting a sweep-feeding strategy they maintained their large body size by avoiding competition, and persisted throughout the Late Palaeozoic while the predatory nektonic Eurypterina (including the giant pterygotids) declined during the Devonian, possibly out-competed by other predators including jawed vertebrates. PMID:19828493

  14. Starvation reveals the cause of infection-induced castration and gigantism

    PubMed Central

    Cressler, Clayton E.; Nelson, William A.; Day, Troy; McCauley, Edward

    2014-01-01

    Parasites often induce life-history changes in their hosts. In many cases, these infection-induced life-history changes are driven by changes in the pattern of energy allocation and utilization within the host. Because these processes will affect both host and parasite fitness, it can be challenging to determine who benefits from them. Determining the causes and consequences of infection-induced life-history changes requires the ability to experimentally manipulate life history and a framework for connecting life history to host and parasite fitness. Here, we combine a novel starvation manipulation with energy budget models to provide new insights into castration and gigantism in the Daphnia magna–Pasteuria ramosa host–parasite system. Our results show that starvation primarily affects investment in reproduction, and increasing starvation stress reduces gigantism and parasite fitness without affecting castration. These results are consistent with an energetic structure where the parasite uses growth energy as a resource. This finding gives us new understanding of the role of castration and gigantism in this system, and how life-history variation will affect infection outcome and epidemiological dynamics. The approach of combining targeted life-history manipulations with energy budget models can be adapted to understand life-history changes in other disease systems. PMID:25143034

  15. Ecological explanations to island gigantism: dietary niche divergence, predation, and size in an endemic lizard.

    PubMed

    Runemark, Anna; Sagonas, Kostas; Svensson, Erik I

    2015-08-01

    Although rapid evolution of body size on islands has long been known, the ecological mechanisms behind this island phenomenon remain poorly understood. Diet is an important selective pressure for morphological divergence. Here we investigate if selection for novel diets has contributed to the multiple independent cases of island gigantism in the Skyros wall lizard (Podarcis gaigeae) and if diet, predation, or both factors best explain island gigantism. We combined data on body size, shape, bite force, and realized and available diets to address this. Several lines of evidence suggest that diet has contributed to the island gigantism. The larger islet lizards have relatively wider heads and higher bite performance in relation to mainland lizards than would be expected from size differences alone. The proportions of consumed and available hard prey are higher on islets than mainland localities, and lizard body size is significantly correlated with the proportion of hard prey. Furthermore, the main axis of divergence in head shape is significantly correlated with dietary divergence. Finally, a model with only diet and one including diet and predation regime explain body size divergence equally well. Our results suggest that diet is an important ecological factor behind insular body size divergence, but could be consistent with an additional role for predation. PMID:26405734

  16. Vínculos observacionais para o processo-S em estrelas gigantes de Bário

    NASA Astrophysics Data System (ADS)

    Smiljanic, R. H. S.; Porto de Mello, G. F.; da Silva, L.

    2003-08-01

    Estrelas de bário são gigantes vermelhas de tipo GK que apresentam excessos atmosféricos dos elementos do processo-s. Tais excessos são esperados em estrelas na fase de pulsos térmicos do AGB (TP-AGB). As estrelas de bário são, no entanto, menos massivas e menos luminosas que as estrelas do AGB, assim, não poderiam ter se auto-enriquecido. Seu enriquecimento teria origem em uma estrela companheira, inicialmente mais massiva, que evolui pelo TP-AGB, se auto-enriquece com os elementos do processo-s e transfere material contaminado para a atmosfera da atual estrela de bário. A companheira evolui então para anã branca deixando de ser observada diretamente. As estrelas de bário são, portanto, úteis como testes observacionais para teorias de nucleossíntese pelo processo-s, convecção e perda de massa. Análises detalhadas de abundância com dados de alta qualidade para estes objetos são ainda escassas na literatura. Neste trabalho construímos modelos de atmosferas e, procedendo a uma análise diferencial, determinamos parâmetros atmosféricos e evolutivos de uma amostra de dez gigantes de bário e quatro normais. Determinamos seus padrões de abundância para Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Y, Zr, Ba, La, Ce, Nd, Sm, Eu e Gd, concluindo que algumas estrelas classificadas na literatura como gigantes de bário são na verdade gigantes normais. Comparamos dois padrões médios de abundância, para estrelas com grandes excessos e estrelas com excessos moderados, com modelos teóricos de enriquecimento pelo processo-s. Os dois grupos de estrelas são ajustados pelos mesmos parâmetros de exposição de nêutrons. Tal resultado sugere que a ocorrência do fenômeno de bário com diferentes intensidades não se deve a diferentes exposições de nêutrons. Discutimos ainda efeitos nucleossintéticos, ligados ao processo-s, sugeridos na literatura para os elementos Cu, Mn, V e Sc.

  17. Formación y evolución de planetas gigantes

    NASA Astrophysics Data System (ADS)

    Benvenuto, O. G.; Brunini, A.

    Presentamos el estado actual del trabajo que estamos realizando en el estudio de la formación de planetas gigantes. Detallamos los algoritmos numéricos necesarios para realizar este tipo de cálculo. Presentamos algunos resultados de la formación de objetos con masas de hasta una docena de veces la del planeta Júpiter, resaltando las principales caracteríticas. Finalmente detallamos los problemas que pensamos abordar en un futuro cercano en este tema de investigación.

  18. A gigantic coronal jet ejected from a compact active region in a coronal hole

    NASA Technical Reports Server (NTRS)

    Shibata, K.; Nitta, N.; Strong, K. T.; Matsumoto, R.; Yokoyama, T.; Hirayama, T.; Hudson, H.; Ogawara, Y.

    1994-01-01

    A gigantic coronal jet greater than 3 x 10(exp 5) km long (nearly half the solar radius) has been found with the soft X-ray telescope (SXT) on board the solar X-ray satellite, Yohkoh. The jet was ejected on 1992 January 11 from an 'anemone-type' active region (AR) appearing in a coronal hole and is one of the largest coronal X-ray jets observed so far by SXT. This gigantic jet is the best observed example of many other smaller X-ray jets, because the spatial structures of both the jet and the AR located at its base are more easily resolved. The range of apparent translational velocities of the bulk of the jet was between 90 and 240 km s(exp -1), with the corresponding kinetic energy estimated to be of order of 10(exp 28) ergs. A detailed analysis reveals that the jet was associated with a loop brightening (a small flare) that occurred in the active region. Several features of this observation suggest and are consistent with a magnetic reconnection mechanism for the production of such a 'jet-loop-brightening' event.

  19. A gigantic coronal jet ejected from a compact active region in a coronal hole

    NASA Astrophysics Data System (ADS)

    Shibata, K.; Nitta, N.; Strong, K. T.; Matsumoto, R.; Yokoyama, T.; Hirayama, T.; Hudson, H.; Ogawara, Y.

    1994-08-01

    A gigantic coronal jet greater than 3 x 105 km long (nearly half the solar radius) has been found with the soft X-ray telescope (SXT) on board the solar X-ray satellite, Yohkoh. The jet was ejected on 1992 January 11 from an 'anemone-type' active region (AR) appearing in a coronal hole and is one of the largest coronal X-ray jets observed so far by SXT. This gigantic jet is the best observed example of many other smaller X-ray jets, because the spatial structures of both the jet and the AR located at its base are more easily resolved. The range of apparent translational velocities of the bulk of the jet was between 90 and 240 km s-1, with the corresponding kinetic energy estimated to be of order of 1028 ergs. A detailed analysis reveals that the jet was associated with a loop brightening (a small flare) that occurred in the active region. Several features of this observation suggest and are consistent with a magnetic reconnection mechanism for the production of such a 'jet-loop-brightening' event.

  20. The small but clear gravity signal above the natural cave 'Grotta Gigante' (Trieste, Italy)

    NASA Astrophysics Data System (ADS)

    Braitenberg, Carla; Sampietro, Daniele; Zuliani, David; Barbagallo, Alfio; Fabris, Paolo; Fabbri, Julius; Rossi, Lorenzo; Handi Mansi, Ahmed

    2014-05-01

    Gravity observations are a powerful means for detecting underground mass changes. The Italian and Slovenian Karst has a number of explored caves, several are also touristic due to their size (e.g. Grotta Gigante in Italy; Skocjianske Jame and Postojnska Jama in Slovenia). Just a few years ago another big cave was discovered by chance close to Trieste when drilling a tunnel for a motor-highway, which shows that more caves are expected to be discovered in coming years. We have acquired the gravity field above the Grotta Gigante cave, a cave roughly 100 m high and 200 m long with a traditional spring-gravity meter (Lacoste&Romberg) and height measurements made with GPS and total station. The GPS was made with two different teams and processing algorithms, to cross-check accuracy and error estimate. Some stations had to be surveyed with a classical instrument due to the vegetation which concealed the satellite positioning signal. Here we present the results of the positioning acquisitions and the gravity field. The cave produces a signal of 1.5 mGal, with a clear elongated concentric symmetry. The survey shows that a systematic coverage of the Karst would have the benefit to recover the position of all of the greater existing caves. This will have a large impact on civil and environmental purposes, since it will for example allow to plan the urban development at a safety distance from subsurface caves.

  1. Pituitary gigantism presenting with depressive mood disorder and diabetic ketoacidosis in an Asian adolescent.

    PubMed

    Kuo, Sheng-Fong; Chuang, Wen-Yu; Ng, Sohching; Chen, Chih-Hung; Chang, Chen-Nen; Chou, Chi-Hsiang; Weng, Wei-Chieh; Yeh, Chih-Hua; Lin, Jen-Der

    2013-01-01

    Hyperglycemia is seldom described in young patients with pituitary gigantism. Here, we describe the case of a 17-year-old Taiwanese boy who developed depressive mood disorder and diabetic ketoacidosis (DKA) at the presentation of pituitary gigantism. The boy complained of lethargy and dysphoric mood in June 2008. He presented at the emergency department with epigastralgia and dyspnea in January 2009. Results of laboratory tests suggested type 1 diabetes mellitus with DKA. However, serum C-peptide level was normal on follow-up. Although he had no obvious features of acral enlargement, a high level of insulin-like growth factor 1 was detected, and a 75 g oral glucose suppression test showed no suppression of serum growth hormone levels. A pituitary macroadenoma was found on subsequent magnetic resonance imaging. The pituitary adenoma was surgically removed, followed by gamma-knife radiosurgery, and Sandostatin long-acting release treatment. He was then administered metformin, 500 mg twice daily, and to date, his serum glycohemoglobin has been <7%. PMID:23729615

  2. One-pot versus sequential reactions in the self-assembly of gigantic nanoscale polyoxotungstates.

    PubMed

    Gao, Jing; Yan, Jun; Beeg, Sebastian; Long, De-Liang; Cronin, Leroy

    2013-02-01

    By using a new type of lacunary tungstoselenite {Se(2)W(29)O(103)} (1), which contains a "defect" pentagonal {W(W)(4)} unit, we explored the assembly of clusters using this building block and demonstrate how this unit can give rise to gigantic nanomolecular species, using both a "one-pot" and "stepwise" synthetic assembly approach. Specifically, exploration of the one-pot synthetic parameter space lead to the discovery of {Co(2.5)(W(3.5)O(14))(SeW(9)O(33))(Se(2)W(30)O(107))} (2), {CoWO(H(2)O)(3)(Se(2)W(26)O(85))(Se(3)W(30)O(107))(2)} (3), and {Ni(2)W(2)O(2)Cl(H(2)O)(3)(Se(2)W(29)O(103)) (Se(3)W(30)O(107))(2)} (4), effectively demonstrating the potential of the {Se(2)W(29)} based building blocks, which was further extended by the isolation of a range of 3d transition metal doped tetramer family derivatives: {M(2)W(n)O(m)(H(2)O)(m)(Se(2)W(29)O(102))(4)} (M = Mn, Co, Ni or Zn, n = 2, m = 4; M = Cu, n = 3, m = 5) (5-9). To contrast the 'one-pot' approach, an optimized stepwise self-assembly investigation utilizing 1 as a precursor was performed showing that the high nuclearity clusters can condense in a more controllable way allowing the tetrameric clusters (5-8) to be synthesized with higher yield, but it was also shown that 1 can be used to construct a gigantic {W(174)} hexameric-cluster {Cu(9)Cl(3)(H(2)O)(18)(Se(2)W(29)O(102))(6)} (10). Further, 1 can also dimerize to {(Se(2)W(30)O(105))(2)} (11) by addition of extra tungstate under similar conditions. All the clusters were characterized by single-crystal X-ray crystallography, chemical analysis, infrared spectroscopy, thermogravimetric analysis, and electrospray ionization mass spectrometry, which remarkably showed that all the clusters, even the largest cluster, 10 (∼50 kD), could be observed as the intact cluster demonstrating the extraordinary potential of this approach to construct robust gigantic nanoscale polyoxotungstates. PMID:23244039

  3. Intraspecific competition and high food availability are associated with insular gigantism in a lizard

    NASA Astrophysics Data System (ADS)

    Pafilis, Panayiotis; Meiri, Shai; Foufopoulos, Johannes; Valakos, Efstratios

    2009-09-01

    Resource availability, competition, and predation commonly drive body size evolution. We assess the impact of high food availability and the consequent increased intraspecific competition, as expressed by tail injuries and cannibalism, on body size in Skyros wall lizards ( Podarcis gaigeae). Lizard populations on islets surrounding Skyros (Aegean Sea) all have fewer predators and competitors than on Skyros but differ in the numbers of nesting seabirds. We predicted the following: (1) the presence of breeding seabirds (providing nutrients) will increase lizard population densities; (2) dense lizard populations will experience stronger intraspecific competition; and (3) such aggression, will be associated with larger average body size. We found a positive correlation between seabird and lizard densities. Cannibalism and tail injuries were considerably higher in dense populations. Increases in cannibalism and tail loss were associated with large body sizes. Adult cannibalism on juveniles may select for rapid growth, fuelled by high food abundance, setting thus the stage for the evolution of gigantism.

  4. Giants among larges: how gigantism impacts giant virus entry into amoebae.

    PubMed

    Rodrigues, Rodrigo Araújo Lima; Abrahão, Jônatas Santos; Drumond, Betânia Paiva; Kroon, Erna Geessien

    2016-06-01

    The proposed order Megavirales comprises the nucleocytoplasmic large DNA viruses (NCLDV), infecting a wide range of hosts. Over time, they co-evolved with different host cells, developing various strategies to penetrate them. Mimiviruses and other giant viruses enter cells through phagocytosis, while Marseillevirus and other large viruses explore endocytosis and macropinocytosis. These differing strategies might reflect the evolution of those viruses. Various scenarios have been proposed for the origin and evolution of these viruses, presenting one of the most enigmatic issues to surround these microorganisms. In this context, we believe that giant viruses evolved independently by massive gene/size gain, exploring the phagocytic pathway of entry into amoebas. In response to gigantism, hosts developed mechanisms to evade these parasites. PMID:27039270

  5. A gigantic, exceptionally complete titanosaurian sauropod dinosaur from southern Patagonia, Argentina.

    PubMed

    Lacovara, Kenneth J; Lamanna, Matthew C; Ibiricu, Lucio M; Poole, Jason C; Schroeter, Elena R; Ullmann, Paul V; Voegele, Kristyn K; Boles, Zachary M; Carter, Aja M; Fowler, Emma K; Egerton, Victoria M; Moyer, Alison E; Coughenour, Christopher L; Schein, Jason P; Harris, Jerald D; Martínez, Rubén D; Novas, Fernando E

    2014-01-01

    Titanosaurian sauropod dinosaurs were the most diverse and abundant large-bodied herbivores in the southern continents during the final 30 million years of the Mesozoic Era. Several titanosaur species are regarded as the most massive land-living animals yet discovered; nevertheless, nearly all of these giant titanosaurs are known only from very incomplete fossils, hindering a detailed understanding of their anatomy. Here we describe a new and gigantic titanosaur, Dreadnoughtus schrani, from Upper Cretaceous sediments in southern Patagonia, Argentina. Represented by approximately 70% of the postcranial skeleton, plus craniodental remains, Dreadnoughtus is the most complete giant titanosaur yet discovered, and provides new insight into the morphology and evolutionary history of these colossal animals. Furthermore, despite its estimated mass of about 59.3 metric tons, the bone histology of the Dreadnoughtus type specimen reveals that this individual was still growing at the time of death. PMID:25186586

  6. Gigantic directional asymmetry of luminescence in multiferroic CuB 2O 4

    NASA Astrophysics Data System (ADS)

    Toyoda, S.; Abe, N.; Arima, T.

    2016-05-01

    In multiferroic materials, luminescence intensities can be direction dependent, i.e., different between the opposite propagating directions of emitted light. However, the effect has not been thought to be used for technological applications, since only small directional asymmetry has been reported so far. Here we show that the effect is robust in multiferroic CuB2O4 . The luminescence intensity changes by about 70 % between the opposite directions of the emission, which is about 100 times larger than the previously reported values. We demonstrate that such a gigantic directional asymmetry of luminescence can be applied to the imaging of canted antiferromagnetic domains. The observation of the effect and its application to magnetic domain imaging are important for a deeper understanding of light-matter interactions as well as technological applications such as optical reading techniques for magnetic memory devices.

  7. Gate-tunable gigantic lattice deformation in VO{sub 2}

    SciTech Connect

    Okuyama, D. E-mail: nakano@imr.tohoku.ac.jp Hatano, T.; Nakano, M. E-mail: nakano@imr.tohoku.ac.jp; Takeshita, S.; Ohsumi, H.; Tardif, S.; Shibuya, K.; Yumoto, H.; Koyama, T.; Ohashi, H.; Takata, M.; Kawasaki, M.; Tokura, Y.; Iwasa, Y. E-mail: nakano@imr.tohoku.ac.jp; Arima, T.

    2014-01-13

    We examined the impact of electric field on crystal lattice of vanadium dioxide (VO{sub 2}) in a field-effect transistor geometry by in-situ synchrotron x-ray diffraction measurements. Whereas the c-axis lattice parameter of VO{sub 2} decreases through the thermally induced insulator-to-metal phase transition, the gate-induced metallization was found to result in a significant increase of the c-axis length by almost 1% from that of the thermally stabilized insulating state. We also found that this gate-induced gigantic lattice deformation occurs even at the thermally stabilized metallic state, enabling dynamic control of c-axis lattice parameter by more than 1% at room temperature.

  8. The Early ULF Signal of the Gigantic Jets Revealed By Hilbert-Huang Transform

    NASA Astrophysics Data System (ADS)

    Huang, Po-Hsun; Bing-Chih Chen, Alfred

    2015-04-01

    The conventional Fourier analysis on the sferics in ULF and VLF bandpasses has been done for years. Several phenomena e.g. whistler and Schumann resonance have been well studied by the Fourier spectrum comprehensively. But the Fourier analysis is computed by an integration over time, therefore, the temporal resolution is smoothed, and limited not only by the sampling rate but also the size of the integration window. The instantaneous frequency can't be obtained through this conventional approach. We introduce the Hilbert-Huang transform (HHT) instead of Fourier transform to analyze the sferics of TLEs recorded at Lulin observatory. The Hilbert-Huang transform decomposes a signal into so-called intrinsic mode functions (IMF), and derive instantaneous frequency data by differentiating the phase angle yielded by Hilbert transform. Our analysis of HHT on several gigantic jets recorded by ground observation surprisingly revealed an early signal of frequency-change during the phase of the leading jet, and this early signal can not be identified by Fourier analysis. In the phase of leading jet, the amplitude of the sferics remains a constant and no significant features are recognized in the recorded waveform, but an obvious frequency change about 100-200 millisecond prior to the main discharge of the full development jets (FDJs), which can be clearly recognized in the HHT spectra of all observed gigantic jets. From a further simulation, this frequency change is confirmed to come from the nature of the discharge, not an alias or a false signal generated by the analysis method. This early signal may implies an in-cloud discharge process which is suggested by Krehbiel et al. [2008

  9. Can Oxygen Set Thermal Limits in an Insect and Drive Gigantism?

    PubMed Central

    Verberk, Wilco C. E. P.; Bilton, David T.

    2011-01-01

    Background Thermal limits may arise through a mismatch between oxygen supply and demand in a range of animal taxa. Whilst this oxygen limitation hypothesis is supported by data from a range of marine fish and invertebrates, its generality remains contentious. In particular, it is unclear whether oxygen limitation determines thermal extremes in tracheated arthropods, where oxygen limitation may be unlikely due to the efficiency and plasticity of tracheal systems in supplying oxygen directly to metabolically active tissues. Although terrestrial taxa with open tracheal systems may not be prone to oxygen limitation, species may be affected during other life-history stages, particularly if these rely on diffusion into closed tracheal systems. Furthermore, a central role for oxygen limitation in insects is envisaged within a parallel line of research focussing on insect gigantism in the late Palaeozoic. Methodology/Principal Findings Here we examine thermal maxima in the aquatic life stages of an insect at normoxia, hypoxia (14 kPa) and hyperoxia (36 kPa). We demonstrate that upper thermal limits do indeed respond to external oxygen supply in the aquatic life stages of the stonefly Dinocras cephalotes, suggesting that the critical thermal limits of such aquatic larvae are set by oxygen limitation. This could result from impeded oxygen delivery, or limited oxygen regulatory capacity, both of which have implications for our understanding of the limits to insect body size and how these are influenced by atmospheric oxygen levels. Conclusions/Significance These findings extend the generality of the hypothesis of oxygen limitation of thermal tolerance, suggest that oxygen constraints on body size may be stronger in aquatic environments, and that oxygen toxicity may have actively selected for gigantism in the aquatic stages of Carboniferous arthropods. PMID:21818347

  10. A Gray-purple Mass on the Floor of the Mouth: Gigantic Mucogingival Pyogenic Granuloma in a Teenage Patient

    PubMed Central

    Brunet-LLobet, Lluís; Miranda-Rius, Jaume; Lahor-Soler, Eduard; Mrina, Ombeni; Nadal, Alfons

    2014-01-01

    Pyogenic granuloma is defined as a benign neoplasm of vascular phenotype. This case describes the clinical and histopathological features of a gigantic mucogingival pyogenic granuloma, in a 14-year-old healthy black boy. This exophytic gray-purple mass, related to a toothpick injury, had more than twelve-month evolution on the anterior mandible involving lingual area besides to the floor of the mouth pressing the right salivary duct. Conservative excision was performed, followed by uncomplicated healing with no recurrence in two years. The histopathological examination reported a pyogenic granuloma (lobular capillary haemangioma). The authors provide a discussion of the presurgical differential diagnosis of the lesion. This case report presents an extremely uncommon location of a gigantic pyogenic granuloma, involving mucogingival complex and affecting the salivary outflow. This clinical manuscript may shed light on the controversies about possible mechanisms inducing oral pyogenic granuloma. PMID:24987485

  11. Peculiarities of the geologic structure of gigantic gas fields of the western Siberian oil and gas province

    SciTech Connect

    Belyi, N.

    1991-03-01

    The Western Siberian Oil and Gas Province is a unique one regarding the concentration of natural gas resources in Mesozoic terrigenous formations. Discovery of gigantic natural gas fields makes it possible to provide high level of gas production for future prospects. The USSR has enormous potential possibilities for discoveries of new natural gas fields onshore, as well as offshore. At present, three gigantic gas fields have been developed, namely Medvezhie, Urongoi, and Yamburg. The first one has been in operation for 18 years. In the Mesozoic section, three productive complexes can be noticed: Upper Cretaceous, Lower Cretaceous, and Jurassic. The Upper Cretaceous production complex is mostly explored, with unique gas resources containing mainly methane having been discovered. The Lower Cretaceous production complex is characterized by considerable lithofaceous uniformity of reservoirs. Gas pools of this complex contain considerable quantities of condensate quite often having oil rims. The Jurassic production complex, which is characterized by its complicated structure and considerable changeability of the filtration properties, is less studied. Study of the geological structural peculiarities of the gigantic gas fields of Western Siberia gives us the possibility to find new approval for the development and exploration of gas fields.

  12. Gravity combined with laser-scan in Grotta Gigante: a benchmark cave for gravity studies

    NASA Astrophysics Data System (ADS)

    Pivetta, Tommaso; Braitenberg, Carla

    2014-05-01

    Laser scanning has become one of the most important topographic techniques in the last decades, due to its ability to reconstruct complex surfaces with high resolution and precision and due to its fast acquisition time. Recently a laser-scan survey has been acquired (Fingolo et al., 2011) in the "Grotta Gigante" cave near Trieste, Italy, the biggest cave worldwide according to the Guinness Awards. In this paper this survey is used to obtain a 3D discretization of the cave with prisms. Then through this new model, with the densities derived from campaign measurements, the exact gravimetric effect of the structure was computed (Nagy et al., 2000) and compared with the gravity observation at the surface. The transition from the cloud of laser-scan points to the prism model was carried out by different computer elaborations; first of all the reduction of the data density through an averaging process that allows to pass from over 10000 points/m2 to less than 10points/m2. Then the whole dataset was filtered from the outliers by the means of a simple quadratic surface that fit the data (Turner, 1999). The reduced data points should be divided into the 2 surfaces of top and bottom, that are used to define the prisms. This step was performed using the local regression method (Loess) to calculate a surface located halfway between top and bottom points. Once the top and bottom interfaces were obtained it was possible to get the final prism representation and calculate the gravity signal. The observed Bouguer field is explained very well by our model and the residuals are used to evaluate possible secondary caves. The final prism model together with the gravity database on surface and inside the cave form a perfect benchmark to test forward and inverse potential field algorithms. References Fingolo M., Facco L., Ceccato A., Breganze C., Paganini P., Cezza M., Grotta Gigante di Trieste. Tra realtà virtuale e rilievi 3D ad alta risoluzione, Veneto Geologi, 75, pp.21-25, 2011

  13. Lower limb gigantism, lymphedema, and painful varicosities following a thigh vascular access graft.

    PubMed

    Thompson, Michael; Mathuram Thiyagarajan, Umasankar; Akoh, Jacob A

    2014-07-01

    Prosthetic arteriovenous grafts (AVGs) are associated with greater morbidity than autogenous arteriovenous fistulas (AVFs), but their use is indicated when AVF formation is not possible. This report adds to the literature a case of lower limb gigantism, painful varicosities, and lymphedema following long-term use of AVG in the upper thigh. The patient's past medical history included renal transplantation on the same side well before the AVG was inserted and right leg deep vein thrombosis. Suspicion of AVG thrombosis was excluded by Doppler ultrasound, which demonstrated an access flow of 1700 mL/min. A computed tomography (CT) scan of the abdomen and pelvis did not identify the cause of her symptoms. Whereas functional incompetence of the iliac vein valve might be responsible for the varicosities, the extent of hypertrophy in this case raises the suspicion of lymphatic blockage possibly secondary to groin dissection undertaken at the time of graft insertion, in addition to the previous dissection at the time of transplantation. This case highlights the need for minimal groin dissection during AVG insertion, particularly in patients with a history of previous abdominopelvic surgery. PMID:24467313

  14. The properties of a gigantic jet reflected in a simultaneous sprite: Observations interpreted by a model

    NASA Astrophysics Data System (ADS)

    Neubert, T.; Chanrion, O.; Arnone, E.; Zanotti, F.; Cummer, S.; Li, J.; Füllekrug, M.; Soula, S.; van der Velde, O.

    2011-12-01

    Thunderstorm clouds may discharge directly to the ionosphere in spectacular luminous jets - the largest electric discharges of our planet. The properties of these “giants,” such as their polarity, conductivity, and currents, have been predicted by models, but are poorly characterized by measurements. A recent observation of a giant, fortuitously illuminated by an unusual sprite discharge in the mesosphere, allows us to study their electric properties and effects on the atmosphere-ionosphere. We show from a first-principles model of the combined giant and sprite event that the observations are consistent with the nature of the giant being a leader in the stratosphere of line charge density ˜0.8 mCm-1 and of multiple streamers in the mesosphere. It is further shown that the giant modifies the free electron content of the lower ionosphere because of electric field-driven ionization, electron attachment and detachment processes. This is the first time that sprites are used for sounding the properties of the mesosphere. The results presented here will allow evaluation of theories for jet and gigantic jets and of their influence on the atmosphere and ionosphere.

  15. A Thermodynamic, kinematic and microphysical analysis of a jet and gigantic jet-producing Florida thunderstorm

    NASA Astrophysics Data System (ADS)

    Lazarus, S. M.; Splitt, M. E.; Brownlee, James; Spiva, Nicholas; Liu, Ningyu

    2015-08-01

    This paper presents a meteorological analysis of a storm that produced two jets, four gigantic jets (GJ), and a starter, which were observed by two radars as well as the Kennedy Space Center 4-Dimensional Lightning Surveillance System on 3 August 2013 in Central Florida. The work is the first application of dual polarization data to a jet-producing storm and is the fifth case related to a tropical disturbance. The storm environment is consistent with the moist tropical paradigm that characterizes about three quarters of the surface and aircraft observed jet and GJ events. The most unstable (MU) convective available potential energy is not unusual for Florida summer convection and is below the climatological mean for these events. An unusual speed shear layer is located near the storm equilibrium level (EL) and the storm exhibits a tilted structure with CGs displaced upshear. The turbulence, as measured by the eddy dissipation rate, is extreme near the storm top during the event window, consistent with the GJ mixing hypothesis. The individual events are collocated with, and track along, the center axis of the divergent outflow at the EL and occur within the region of the coldest GOES IR temperatures—placing the events within the overshoot. The dual polarization data indicate a deep graupel column, extending above the mixed phase layer, to a 13 km altitude.

  16. A gigantic new dinosaur from Argentina and the evolution of the sauropod hind foot

    PubMed Central

    González Riga, Bernardo J.; Lamanna, Matthew C.; Ortiz David, Leonardo D.; Calvo, Jorge O.; Coria, Juan P.

    2016-01-01

    Titanosauria is an exceptionally diverse, globally-distributed clade of sauropod dinosaurs that includes the largest known land animals. Knowledge of titanosaurian pedal structure is critical to understanding the stance and locomotion of these enormous herbivores and, by extension, gigantic terrestrial vertebrates as a whole. However, completely preserved pedes are extremely rare among Titanosauria, especially as regards the truly giant members of the group. Here we describe Notocolossus gonzalezparejasi gen. et sp. nov. from the Upper Cretaceous of Mendoza Province, Argentina. With a powerfully-constructed humerus 1.76 m in length, Notocolossus is one of the largest known dinosaurs. Furthermore, the complete pes of the new taxon exhibits a strikingly compact, homogeneous metatarsus—seemingly adapted for bearing extraordinary weight—and truncated unguals, morphologies that are otherwise unknown in Sauropoda. The pes underwent a near-progressive reduction in the number of phalanges along the line to derived titanosaurs, eventually resulting in the reduced hind foot of these sauropods. PMID:26777391

  17. A gigantic new dinosaur from Argentina and the evolution of the sauropod hind foot.

    PubMed

    González Riga, Bernardo J; Lamanna, Matthew C; Ortiz David, Leonardo D; Calvo, Jorge O; Coria, Juan P

    2016-01-01

    Titanosauria is an exceptionally diverse, globally-distributed clade of sauropod dinosaurs that includes the largest known land animals. Knowledge of titanosaurian pedal structure is critical to understanding the stance and locomotion of these enormous herbivores and, by extension, gigantic terrestrial vertebrates as a whole. However, completely preserved pedes are extremely rare among Titanosauria, especially as regards the truly giant members of the group. Here we describe Notocolossus gonzalezparejasi gen. et sp. nov. from the Upper Cretaceous of Mendoza Province, Argentina. With a powerfully-constructed humerus 1.76 m in length, Notocolossus is one of the largest known dinosaurs. Furthermore, the complete pes of the new taxon exhibits a strikingly compact, homogeneous metatarsus--seemingly adapted for bearing extraordinary weight--and truncated unguals, morphologies that are otherwise unknown in Sauropoda. The pes underwent a near-progressive reduction in the number of phalanges along the line to derived titanosaurs, eventually resulting in the reduced hind foot of these sauropods. PMID:26777391

  18. A gigantic bird-like dinosaur from the Late Cretaceous of China.

    PubMed

    Xu, Xing; Tan, Qingwei; Wang, Jianmin; Zhao, Xijin; Tan, Lin

    2007-06-14

    An evolutionary trend of decreasing size is present along the line to birds in coelurosaurian theropod evolution, but size increases are seen in many coelurosaurian subgroups, in which large forms are less bird-like. Here we report on a new non-avian dinosaur, Gigantoraptor erlianensis, gen. et sp. nov., from the Late Cretaceous Iren Dabasu Formation of Nei Mongol, China. Although it has a body mass of about 1,400 kg, a phylogenetic analysis positions this new taxon within the Oviraptorosauria, a group of small, feathered theropods rarely exceeding 40 kg in body mass. A histological analysis suggests that Gigantoraptor gained this size by a growth rate considerably faster than large North American tyrannosaurs such as Albertosaurus and Gorgosaurus. Gigantoraptor possesses several salient features previously unknown in any other dinosaur and its hind limb bone scaling and proportions are significantly different from those of other coelurosaurs, thus increasing the morphological diversity among dinosaurs. Most significantly, the gigantic Gigantoraptor shows many bird-like features absent in its smaller oviraptorosaurian relatives, unlike the evolutionary trend seen in many other coelurosaurian subgroups. PMID:17565365

  19. Discovery of gigantic molecular nanostructures using a flow reaction array as a search engine

    PubMed Central

    Zang, Hong-Ying; de la Oliva, Andreu Ruiz; Miras, Haralampos N.; Long, De-Liang; McBurney, Roy T.; Cronin, Leroy

    2014-01-01

    The discovery of gigantic molecular nanostructures like coordination and polyoxometalate clusters is extremely time-consuming since a vast combinatorial space needs to be searched, and even a systematic and exhaustive exploration of the available synthetic parameters relies on a great deal of serendipity. Here we present a synthetic methodology that combines a flow reaction array and algorithmic control to give a chemical ‘real-space’ search engine leading to the discovery and isolation of a range of new molecular nanoclusters based on [Mo2O2S2]2+-based building blocks with either fourfold (C4) or fivefold (C5) symmetry templates and linkers. This engine leads us to isolate six new nanoscale cluster compounds: 1, {Mo10(C5)}; 2, {Mo14(C4)4(C5)2}; 3, {Mo60(C4)10}; 4, {Mo48(C4)6}; 5, {Mo34(C4)4}; 6, {Mo18(C4)9}; in only 200 automated experiments from a parameter space spanning ~5 million possible combinations. PMID:24770632

  20. Discovery of gigantic molecular nanostructures using a flow reaction array as a search engine.

    PubMed

    Zang, Hong-Ying; de la Oliva, Andreu Ruiz; Miras, Haralampos N; Long, De-Liang; McBurney, Roy T; Cronin, Leroy

    2014-01-01

    The discovery of gigantic molecular nanostructures like coordination and polyoxometalate clusters is extremely time-consuming since a vast combinatorial space needs to be searched, and even a systematic and exhaustive exploration of the available synthetic parameters relies on a great deal of serendipity. Here we present a synthetic methodology that combines a flow reaction array and algorithmic control to give a chemical 'real-space' search engine leading to the discovery and isolation of a range of new molecular nanoclusters based on [Mo(2)O(2)S(2)](2+)-based building blocks with either fourfold (C4) or fivefold (C5) symmetry templates and linkers. This engine leads us to isolate six new nanoscale cluster compounds: 1, {Mo(10)(C5)}; 2, {Mo(14)(C4)4(C5)2}; 3, {Mo(60)(C4)10}; 4, {Mo(48)(C4)6}; 5, {Mo(34)(C4)4}; 6, {Mo(18)(C4)9}; in only 200 automated experiments from a parameter space spanning ~5 million possible combinations. PMID:24770632

  1. Evolución de planetas gigantes y posibilidades de su detección directa

    NASA Astrophysics Data System (ADS)

    Brunini, A.; Benvenuto, O. G.

    Desde la reciente detección de planetas gigantes orbitando estrellas cercanas de tipo solar por medio de efecto Doppler, uno de los principales problemas, en cuanto al estudio de los sistemas planetarios extrasolares, se refiere a la posibilidad de obtener evidencia directa de su existencia. Esto parece ser factible gracias a que en un futuro cercano entrarán en operación algunos telescopios especialmente adecuados a estos propósitos. Por tal motivo, hemos comenzado desde hace un tiempo un esfuerzo en cuanto al estudio de la evolución planetaria. A tales efectos hemos adaptado el código de evolución estelar de nuestro Observatorio al caso planetario. Las principales diferencias entre el caso estelar y el planetario se encuentran en la ecuación de estado. A tales fines hemos incluído la reciente ecuación de estado de Saumon, Chabrier y Van Horn, las opacidades radiativas de Guillot et al., procesos de quema de Deuterio, etc. También se ha considerado la posible existencia de fases de hielo y roca en el interior planetario. Por el momento hemos despreciado los efectos de la rotación planetaria. Con este código hemos computado la evolución de planetas con masas desde 10 hasta 0.3 masas de Júpiter. Utilizando nuestros resultados numéricos discutimos la detectabilidad de estos objetos en condiciones realistas.

  2. Respiratory Evolution Facilitated the Origin of Pterosaur Flight and Aerial Gigantism

    PubMed Central

    Claessens, Leon P. A. M.; O'Connor, Patrick M.; Unwin, David M.

    2009-01-01

    Pterosaurs, enigmatic extinct Mesozoic reptiles, were the first vertebrates to achieve true flapping flight. Various lines of evidence provide strong support for highly efficient wing design, control, and flight capabilities. However, little is known of the pulmonary system that powered flight in pterosaurs. We investigated the structure and function of the pterosaurian breathing apparatus through a broad scale comparative study of respiratory structure and function in living and extinct archosaurs, using computer-assisted tomographic (CT) scanning of pterosaur and bird skeletal remains, cineradiographic (X-ray film) studies of the skeletal breathing pump in extant birds and alligators, and study of skeletal structure in historic fossil specimens. In this report we present various lines of skeletal evidence that indicate that pterosaurs had a highly effective flow-through respiratory system, capable of sustaining powered flight, predating the appearance of an analogous breathing system in birds by approximately seventy million years. Convergent evolution of gigantism in several Cretaceous pterosaur lineages was made possible through body density reduction by expansion of the pulmonary air sac system throughout the trunk and the distal limb girdle skeleton, highlighting the importance of respiratory adaptations in pterosaur evolution, and the dramatic effect of the release of physical constraints on morphological diversification and evolutionary radiation. PMID:19223979

  3. Discovery of gigantic molecular nanostructures using a flow reaction array as a search engine

    NASA Astrophysics Data System (ADS)

    Zang, Hong-Ying; de La Oliva, Andreu Ruiz; Miras, Haralampos N.; Long, De-Liang; McBurney, Roy T.; Cronin, Leroy

    2014-04-01

    The discovery of gigantic molecular nanostructures like coordination and polyoxometalate clusters is extremely time-consuming since a vast combinatorial space needs to be searched, and even a systematic and exhaustive exploration of the available synthetic parameters relies on a great deal of serendipity. Here we present a synthetic methodology that combines a flow reaction array and algorithmic control to give a chemical ‘real-space’ search engine leading to the discovery and isolation of a range of new molecular nanoclusters based on [Mo2O2S2]2+-based building blocks with either fourfold (C4) or fivefold (C5) symmetry templates and linkers. This engine leads us to isolate six new nanoscale cluster compounds: 1, {Mo10(C5)}; 2, {Mo14(C4)4(C5)2}; 3, {Mo60(C4)10}; 4, {Mo48(C4)6}; 5, {Mo34(C4)4}; 6, {Mo18(C4)9}; in only 200 automated experiments from a parameter space spanning ~5 million possible combinations.

  4. Optical and radio signatures of negative gigantic jets: Cases from Typhoon Lionrock (2010)

    NASA Astrophysics Data System (ADS)

    Huang, Sung-Ming; Hsu, Rue-Rou; Lee, Li-Jou; Su, Han-Tzong; Kuo, Cheng-Ling; Wu, Chun-Chieh; Chou, Jung-Kuang; Chang, Shu-Chun; Wu, Yen-Jung; Chen, Alfred B.

    2012-08-01

    On 31 August 2010, more than 100 transient luminous events were observed to occur over Typhoon Lionrock when it passed at ˜210 km to the southwest of the NCKU site in Taiwan. Among them, 14 negative gigantic jets (GJs) with clear recognizable morphologies and radio frequency signals are analyzed. These GJs are all found to have negative discharge polarity and thus are type I GJs. Morphologically, they are grouped into three forms: tree-like, carrot-like, and a new intermediate type called tree-carrot-like GJs. The ULF and ELF/VLF band signals of these events contain clear signatures associated with GJ development stages, including the initiating lightning, the leading jet, the fully developed jet, and the trailing jet. Though the radio waveform for each group of GJs always contains a fast descending pulse linked with the surge current upon the GJ-ionosphere contact, the detailed waveforms actually vary substantially. Cross analysis of the optical and radio frequency signals for these GJs indicates that a large surge current moment (CM) (>60 kA-km) appears to be essentially associated with the tree-like GJs. In contrast, the carrot-like and the tree-carrot-like GJs are both related to a surge CM less than 36 kA-km, and a continuing CM less than 27 kA-km further separates the carrot-like GJs from the tree-carrot-like GJs. Furthermore, on the peak CM versus charge moment change diagram for the initiating lightning, different groups of GJs seem to exhibit different trends. This feature suggests that the eventual forms of negative GJs may have been determined at the initiating lightning stage.

  5. Multi-instrumental observations of a positive gigantic jet produced by a winter thunderstorm in Europe

    NASA Astrophysics Data System (ADS)

    van der Velde, Oscar A.; Bór, József; Li, Jingbo; Cummer, Steven A.; Arnone, Enrico; Zanotti, Ferruccio; Füllekrug, Martin; Haldoupis, Christos; Naitamor, Samir; Farges, Thomas

    2010-12-01

    At 2336:56 UTC on 12 December 2009, a bright gigantic jet (GJ) was recorded by an observer in Italy. Forty-nine additional sprites, elves, halos and two cases of upward lightning were observed that night. The location of the GJ corresponded to a distinct cloud top (-34°C) west of Ajaccio, Corsica. The GJ reached approximately 91 km altitude, with a "trailing jet" reaching 49-59 km, matching with earlier reported GJs. The duration was short at 120-160 ms. This is the first documented GJ which emerged from a maritime winter thunderstorm only 6.5 km tall, showing high cloud tops are not required for initiation of GJs. In the presence of strong vertical wind shear, the meteorological situation was different from typical outbreaks of fall and winter thunderstorms in the Mediterranean. During the trailing jet phase of the GJ, a sprite with halo triggered by a nearby cloud-to-ground lightning flash occurred at a relatively low altitude (<72 km). At the same time, the trailing jet and beads were reilluminated. Electromagnetic waveforms from Hungary, Poland, and the USA revealed this GJ is the first reported to transfer negative charge (approximately 136 C) from the ionosphere to the positively charged origins in the cloud (i.e., a positive cloud-to-ionosphere discharge, +CI), with a large total charge moment change of 11600 C km and a maximum current of 3.3 kA. Early VLF transmitter amplitude perturbations detected concurrently with the GJ confirm the production of large conductivity changes due to electron density enhancements in the D-region of the ionosphere.

  6. New color images of sprites, halos and gigantic jets from the International Space Station

    NASA Astrophysics Data System (ADS)

    Yair, Y.; Rubanenko, L.; Mezuman, K.; Elhalel, G.; Pariente, M.; Glickman-Pariente, M.; Ziv, B.; Takahashi, Y.; Inoue, T.

    2012-12-01

    During July-August 2011, Expedition 28/29 JAXA astronaut Satoshi Furukawa conducted TLE observations from the International Space Station in conjunction with the "Cosmic Shore" program produced by NHK. An EMCCD normal video-rate color TV camera was used to conduct directed observations from the Earth-pointing Copula module. The target selection was based on the methodology developed for the MEIDEX sprite campaign on board the space shuttle Columbia in January 2003 (Ziv et al., 2004). We used the Aviation Weather Center (http://aviationweather.gov) daily significant weather forecast maps (SIGWX) to select regions with high probability for convective activity and thunderstorm such that they were within the camera FOV as deduced from the ISS trajectory and distance to the limb (2240 km). For increasing the chance for successful observations, only storms with predicted "Frequent Cb" and cloud tops above 45 Kft (~14 km) were selected. Additionally, we targeted tropical storms and hurricanes over the oceans. The observation geometry was pre-determined and uploaded daily to the ISS with pointing options to limb, oblique or nadir, based on the predicted location of the storm with regards to the ISS. The pointing angle was rotated in real-time according to visual eyesight by the astronaut. We present results of 10 confirmed TLEs: 8 sprites, 1 sprite halo and 1 gigantic jet, out of <2 hours of video. Sprites tend to appear in a single frame simultaneously with maximum lightning brightness. Unique images (a) from nadir of a sprite horizontally displaced form the lightning light and (b) from oblique view of a sprite halo, enable the calculation of dimensions and volumes occupied by these TLEs. Since time stamping on the ISS images was accurate within 1 s, matching with ELF and WWLLN data for the parent lightning location is limited. Nevertheless, the results prove that the ISS is an ideal platform for lightning and TLE observations, and careful operational procedures greatly

  7. Gigantic jets produced by an isolated tropical thunderstorm near Réunion Island

    NASA Astrophysics Data System (ADS)

    Soula, Serge; van der Velde, Oscar; Montanya, Joan; Huet, Patrice; Barthe, Christelle; Bór, József

    2011-10-01

    Five gigantic jets (GJs) have been recorded with video and photograph cameras on 7 March 2010 above an isolated tropical storm east of Réunion Island. Three of them were produced before the storm reached its coldest cloud top temperature (approximately -81°C), and two others occurred during the cloud extension. Thanks to the close distance of observation (˜50 km), the luminosity within the cloud was recorded, and the events are analyzed in unprecedented detail. The tops of the GJs are estimated between 80 and 90 km. All these GJs are accompanied by long, continuous cloud illumination, and they are preceded and followed by intermittent optical flashes from the cloud, most of time without any cloud-to-ground (CG) flash simultaneously detected, which suggests they originated mainly as intracloud discharges and without any charge transfer to Earth. The CG lightning activity is observed to cease a few tens of seconds before the jets. According to ELF data recorded at Nagycenk, Hungary, the five GJs serve to raise negative charge. Their duration ranges from 333 to 850 ms. The leading jet has the most variable duration (33-167 ms) and propagates faster at higher altitudes. The trailing jet exhibits a continuous decrease of luminosity in different parts of the jet (lower channel, transition zone and, for most events, carrot sprite-like top) and in the cloud, with possible rebrightening. The lower channels (˜20-40 km altitude) produce blue luminosity which decreases with altitude and become more and more diffuse with time. The transition zone (around 40-65 km) consists of bright red, luminous beads slowly going up (˜104 m s-1), retracing the initial leading jet channels.

  8. Gigantic lateral spreading of mountains in the epicentral area of the expected Tokai earthquake, central Japan

    NASA Astrophysics Data System (ADS)

    Chigira, Masahiro; Nakamura, Takeshi

    2010-05-01

    Lateral spreading of mountains is not only a degradation process itself but also it could become the background of a catastrophic landslide that occurs at its spreading rims. We found gigantic lateral spreading behind the Yui landsllide area, which is located along the Pacific Sea coast in the epicentral area of the expected Tokai earthquake, central Japan. The Yui landslide area is located on a socially very important place, where are major lifelines connecting east and west Japan: Tokaido railway, Tokaido Shinkansen, and Tomei highway. The Yui landslide area comprises many landslide units and has been causing many catastrophs. The lateral spreading is characterized by NS-trending multiple ridges and linear depressions as long as 1 to 2 km and up to 60 m deep. These features are observable on the aerial photographs and are clearly identified by using airborne laser scanner. Mountains subjected to the lateral spreading is 3 km wide in EW and 6 km long in NS and are 250 to 500 m high above sea level. These morphological features suggest that the NS trending ridges spread laterally to EW and their central parts settled down like the way by which horsts and grabens are made. The ridges are underlain by Miocene beds consisting of the alternating beds of mudstone and sandstone in the lower part and of sandstone and conglomerate in the upper part. The spreading ridge occupies the axial part of a NS-trending syncline, which has a half wave length longer than 2 km and comprises minor folds with a wavelength on the order of hundred meters. This structure, synclinorium, suggests that there could be decollements along the enveloping surface of the minor folds and that the lateral spreading could have a low-angle slip surface along the enveloping surface of the minor folds. There are many landslides along the side slopes of the laterally spread ridges and they have been moving many times by rainstorms and also by earthquakes. The movements are recorded since 1781, but the

  9. Gigantic landslides versus glacial deposits: on origin of large hummock deposits in Alai Valley, Northern Pamir

    NASA Astrophysics Data System (ADS)

    Reznichenko, Natalya

    2015-04-01

    As glaciers are sensitive to local climate, their moraines position and ages are used to infer past climates and glacier dynamics. These chronologies are only valid if all dated moraines are formed as the result of climatically driven advance and subsequent retreat. Hence, any accurate palaeoenvironmental reconstruction requires thorough identification of the landform genesis by complex approach including geomorphological, sedimentological and structural landform investigation. Here are presented the implication of such approach for the reconstruction of the mega-hummocky deposits formation both of glacial and landslide origin in the glaciated Alai Valley of the Northern Pamir with further discussion on these and similar deposits validity for palaeoclimatic reconstructions. The Tibetan Plateau valleys are the largest glaciated regions beyond the ice sheets with high potential to provide the best geological record of glacial chronologies and, however, with higher probabilities of the numerous rock avalanche deposits including those that were initially considered of glacial origin (Hewitt, 1999). The Alai Valley is the largest intermountain depression in the upper reaches of the Amudarja River basin that has captured numerous unidentified extensive hummocky deposits descending from the Zaalai Range of Northern Pamir, covering area in more than 800 km2. Such vast hummocky deposits are usually could be formed either: 1) glacially by rapid glacial retreat due to the climate signal or triggered a-climatically glacial changes, such as glacial surge or landslide impact, or 2) during the landslide emplacement. Combination of sediment tests on agglomerates forming only in rock avalanche material (Reznichenko et al., 2012) and detailed geomorphological and sedimentological descriptions of these deposits allowed reconstructing the glacial deposition in the Koman and Lenin glacial catchments with identification of two gigantic rock avalanches and their relation to this glacial

  10. Exploring the symmetry, structure, and self-assembly mechanism of a gigantic seven-fold symmetric {Pd₈₄} wheel.

    PubMed

    Scullion, Rachel A; Surman, Andrew J; Xu, Feng; Mathieson, Jennifer S; Long, De-Liang; Haso, Fadi; Liu, Tianbo; Cronin, Leroy

    2014-09-15

    The symmetry, structure and formation mechanism of the structurally self-complementary {Pd84} = [Pd84O42(PO4)42(CH3CO2)28](70-) wheel is explored. Not only does the symmetry give rise to a non-closest packed structure, the mechanism of the wheel formation is proposed to depend on the delicate balance between reaction conditions. We achieve the resolution of gigantic polyoxopalladate species through electrophoresis and size-exclusion chromatography, the latter has been used in conjunction with electrospray mass spectrometry to probe the formation of the ring, which was found to proceed by the stepwise aggregation of {Pd6}(-) = [Pd6O4(CH3CO2)2(PO4)3Na(6-n)H(n)](-) building blocks. Furthermore, the higher-order assembly of these clusters into hollow blackberry structures of around 50 nm has been observed using dynamic and static light scattering. PMID:25044792

  11. System of gigantic valleys northwest of Tharsis, Mars: Latent catastrophic flooding, northwest watershed, and implications for northern plains ocean

    USGS Publications Warehouse

    Dohm, J.M.; Anderson, R.C.; Baker, V.R.; Ferris, J.C.; Hare, T.M.; Strom, R.G.; Rudd, L.P.; Rice, J. W., Jr.; Casavant, R.R.; Scott, D.H.

    2000-01-01

    Mars Orbiter Laser Altimeter (MOLA) reveals a system of gigantic valleys to the northwest of the huge martian shield volcano, Arsia Mons, in the western hemisphere of Mars. These newly identified northwestern slope valleys (NSVs) potentially signify previously undocumented martian catastrophic floods and may corroborate the northern ocean hypotheses. These features, which generally correspond spatially to gravity lows, were previously obscurred in Mariner and Viking Orbiter imagery by veneers of materials, including volcanic lava flows and air fall deposits. Geologic investigations of the Tharsis region suggest that the NSVs were mainly carved prior to the construction of Arsia Mons and its associated Late Hesperian and Amazonian age lava flows, concurrent with the early development of the outflow channels that debouch into Chryse Planitia.

  12. Occurrence of gigantic biogenic magnetite during the Paleocene-Eocene Thermal Maximum

    NASA Astrophysics Data System (ADS)

    Schumann, D.; Raub, T. D.; Kopp, R. E.; Guerquin-Kern, J. L.; Wu, T. D.; Rouiller, I.; Smirnov, A. V.; Sears, S. K.; Lücken, U.; Tikoo, S. M.; Hesse, R.; Kirschvink, J. L.; Vali, H.

    2009-04-01

    et al. 2008] to other PETM locations of the Atlantic margin and to a possible modern analog environment. High surface productivity with low-organic carbon density sediments and meter-scale sedimentary suboxic zones are provided by tropical shelves fed by energetic river systems, such as the Amazon. We inverstigated several magnetic extracts of samples taken from the meter-scale suboxic zones of the Amazone delta system. Sluijs A, Brinkhuis H, Schouten S, Bohaty SM, John CM, Zachos JC, Reichart GJ, Damste JSS, Crouch EM, Dickens GR. 2007. Environmental precursors to rapid light carbon injection at the Palaeocene/Eocene boundary. Nature 450:1218-1221. Kopp RE, Raub TD, Schumann D, Vali H, Smirnov AV, Kirschvink JL 2007. Magnetofossil spike during the Paleocene-Eocene thermal maximum: Ferromagnetic resonance, rock magnetic, and electron microscopy evidence from Ancora, New Jersey, United States. Paleoceanography, doi:10.1029/2007pa001473. Lipper PC, Zachos JC 2007. A biogenic origin for anomalous fine-grained magnetic material at the Paleocone-Eocene booundary at Wilson Lake, New Jesery. Paleoceanography, doi:10.1029/2007pa001471. Schumann D, Raub TD, Kopp RE, Guerquin-Kern JL, Wu TD, Rouiller I, Smirnov AV, Sears K, Lücken U, Tikoo SM, Hesse R, Kirschvink JL, Vali H 2008. Gigantism in unique biogenic magnetite at the Paleocene-Eocene Thermal Maximum. PNAS, 105:17648-17653.

  13. Ultrafast gigantic photo-response in charge-ordered organic salt (EDO-TTF)2PF6 on 10-fs time scales

    SciTech Connect

    Itatani, J.; Rini, M.; Cavalleri, A.; Onda, K.; Ishikawa, T.; Ogihara, S.; Koshihara, S.; Shao, X.; Nakano, Y.; Yamochi, H.; Saito, G.; Schoenlein, R.W.

    2008-08-01

    The initial dynamics of photo-induced phase transition in charge-ordered organic salt (EDO-TTF){sub 2}PF{sub 6} was investigated using 10-fs near-infrared laser pulses. We observed sub-20-fs gigantic photo-responses (|{Delta}R/R|>100%) due to intra-molecular vibration and a clear signature of a structural bottleneck ({approx}50 fs) for the first time.

  14. Herbivory and body size: allometries of diet quality and gastrointestinal physiology, and implications for herbivore ecology and dinosaur gigantism.

    PubMed

    Clauss, Marcus; Steuer, Patrick; Müller, Dennis W H; Codron, Daryl; Hummel, Jürgen

    2013-01-01

    Digestive physiology has played a prominent role in explanations for terrestrial herbivore body size evolution and size-driven diversification and niche differentiation. This is based on the association of increasing body mass (BM) with diets of lower quality, and with putative mechanisms by which a higher BM could translate into a higher digestive efficiency. Such concepts, however, often do not match empirical data. Here, we review concepts and data on terrestrial herbivore BM, diet quality, digestive physiology and metabolism, and in doing so give examples for problems in using allometric analyses and extrapolations. A digestive advantage of larger BM is not corroborated by conceptual or empirical approaches. We suggest that explanatory models should shift from physiological to ecological scenarios based on the association of forage quality and biomass availability, and the association between BM and feeding selectivity. These associations mostly (but not exclusively) allow large herbivores to use low quality forage only, whereas they allow small herbivores the use of any forage they can physically manage. Examples of small herbivores able to subsist on lower quality diets are rare but exist. We speculate that this could be explained by evolutionary adaptations to the ecological opportunity of selective feeding in smaller animals, rather than by a physiologic or metabolic necessity linked to BM. For gigantic herbivores such as sauropod dinosaurs, other factors than digestive physiology appear more promising candidates to explain evolutionary drives towards extreme BM. PMID:24204552

  15. Predation as the primary selective force in recurrent evolution of gigantism in Poecilozonites land snails in Quaternary Bermuda

    PubMed Central

    Olson, Storrs L.; Hearty, Paul J.

    2010-01-01

    During the last half million years, pulses of gigantism in the anagenetic lineage of land snails of the subgenus Poecilozonites on Bermuda were correlated with glacial periods when lower sea level resulted in an island nearly an order of magnitude larger than at present. During those periods, the island was colonized by large vertebrate predators that created selection pressure for large size and rapid growth in the snails. Extreme reduction in land area from rising seas, along with changes in ecological conditions at the onset of interglacial episodes, marked extinction events for large predators, after which snails reverted to much smaller size. The giant snails were identical in morphology during the last two glacials when the predators included a large flightless rail Rallus recessus (marine isotope stages (MIS) 4-2) and a crane Grus latipes and a duck Anas pachysceles (MIS 6). In a preceding glacial period (MIS 10), when the fauna also included the tortoise Hesperotestudo bermudae, the snails were not only large, but the shells were much thicker, presumably to prevent crushing by tortoises. Evolution of Poecilozonites provides an outstanding example of dramatic morphological change in response to environmental pressures in the absence of cladogenesis. PMID:20554560

  16. Herbivory and Body Size: Allometries of Diet Quality and Gastrointestinal Physiology, and Implications for Herbivore Ecology and Dinosaur Gigantism

    PubMed Central

    Clauss, Marcus; Steuer, Patrick; Müller, Dennis W. H.; Codron, Daryl; Hummel, Jürgen

    2013-01-01

    Digestive physiology has played a prominent role in explanations for terrestrial herbivore body size evolution and size-driven diversification and niche differentiation. This is based on the association of increasing body mass (BM) with diets of lower quality, and with putative mechanisms by which a higher BM could translate into a higher digestive efficiency. Such concepts, however, often do not match empirical data. Here, we review concepts and data on terrestrial herbivore BM, diet quality, digestive physiology and metabolism, and in doing so give examples for problems in using allometric analyses and extrapolations. A digestive advantage of larger BM is not corroborated by conceptual or empirical approaches. We suggest that explanatory models should shift from physiological to ecological scenarios based on the association of forage quality and biomass availability, and the association between BM and feeding selectivity. These associations mostly (but not exclusively) allow large herbivores to use low quality forage only, whereas they allow small herbivores the use of any forage they can physically manage. Examples of small herbivores able to subsist on lower quality diets are rare but exist. We speculate that this could be explained by evolutionary adaptations to the ecological opportunity of selective feeding in smaller animals, rather than by a physiologic or metabolic necessity linked to BM. For gigantic herbivores such as sauropod dinosaurs, other factors than digestive physiology appear more promising candidates to explain evolutionary drives towards extreme BM. PMID:24204552

  17. Predation as the primary selective force in recurrent evolution of gigantism in Poecilozonites land snails in Quaternary Bermuda.

    PubMed

    Olson, Storrs L; Hearty, Paul J

    2010-12-23

    During the last half million years, pulses of gigantism in the anagenetic lineage of land snails of the subgenus Poecilozonites on Bermuda were correlated with glacial periods when lower sea level resulted in an island nearly an order of magnitude larger than at present. During those periods, the island was colonized by large vertebrate predators that created selection pressure for large size and rapid growth in the snails. Extreme reduction in land area from rising seas, along with changes in ecological conditions at the onset of interglacial episodes, marked extinction events for large predators, after which snails reverted to much smaller size. The giant snails were identical in morphology during the last two glacials when the predators included a large flightless rail Rallus recessus (marine isotope stages (MIS) 4-2) and a crane Grus latipes and a duck Anas pachysceles (MIS 6). In a preceding glacial period (MIS 10), when the fauna also included the tortoise Hesperotestudo bermudae, the snails were not only large, but the shells were much thicker, presumably to prevent crushing by tortoises. Evolution of Poecilozonites provides an outstanding example of dramatic morphological change in response to environmental pressures in the absence of cladogenesis. PMID:20554560

  18. Genetic analysis of durable resistance to Magnaporthe oryzae in the rice accession Gigante Vercelli identified two blast resistance loci.

    PubMed

    Urso, Simona; Desiderio, Francesca; Biselli, Chiara; Bagnaresi, Paolo; Crispino, Laura; Piffanelli, Pietro; Abbruscato, Pamela; Assenza, Federica; Guarnieri, Giada; Cattivelli, Luigi; Valè, Giampiero

    2016-02-01

    Rice cultivars exhibiting durable resistance to blast, the most important rice fungal disease provoking up to 30 % of rice losses, are very rare and searching for sources of such a resistance represents a priority for rice-breeding programs. To this aim we analyzed Gigante Vercelli (GV) and Vialone Nano (VN), two temperate japonica rice cultivars in Italy displaying contrasting response to blast, with GV showing a durable and broad-spectrum resistance, whereas VN being highly susceptible. An SSR-based genetic map developed using a GV × VN population segregating for blast resistance identified two blast resistance loci, localized to the long arm of chromosomes 1 and 4 explaining more than 78 % of the observed phenotypic variation for blast resistance. The pyramiding of two blast resistance QTLs was therefore involved in the observed durable resistance in GV. Mapping data were integrated with information obtained from RNA-seq expression profiling of all classes of resistance protein genes (resistance gene analogs, RGAs) and with the map position of known cloned or mapped blast resistance genes to search candidates for the GV resistant response. A co-localization of RGAs with the LOD peak or the marker interval of the chromosome 1 QTL was highlighted and a valuable tool for selecting the resistance gene during breeding programs was developed. Comparative analysis with known blast resistance genes revealed co-positional relationships between the chromosome 1 QTL with the Pi35/Pish blast resistance alleles and showed that the chromosome 4 QTL represents a newly identified blast resistance gene. The present genetic analysis has therefore allowed the identification of two blast resistance loci in the durable blast-resistant rice cultivar GV and tools for molecular selection of these resistance genes. PMID:26141566

  19. What lies beneath: sub-articular long bone shape scaling in eutherian mammals and saurischian dinosaurs suggests different locomotor adaptations for gigantism.

    PubMed

    Bonnan, Matthew F; Wilhite, D Ray; Masters, Simon L; Yates, Adam M; Gardner, Christine K; Aguiar, Adam

    2013-01-01

    Eutherian mammals and saurischian dinosaurs both evolved lineages of huge terrestrial herbivores. Although significantly more saurischian dinosaurs were giants than eutherians, the long bones of both taxa scale similarly and suggest that locomotion was dynamically similar. However, articular cartilage is thin in eutherian mammals but thick in saurischian dinosaurs, differences that could have contributed to, or limited, how frequently gigantism evolved. Therefore, we tested the hypothesis that sub-articular bone, which supports the articular cartilage, changes shape in different ways between terrestrial mammals and dinosaurs with increasing size. Our sample consisted of giant mammal and reptile taxa (i.e., elephants, rhinos, sauropods) plus erect and non-erect outgroups with thin and thick articular cartilage. Our results show that eutherian mammal sub-articular shape becomes narrow with well-defined surface features as size increases. In contrast, this region in saurischian dinosaurs expands and remains gently convex with increasing size. Similar trends were observed in non-erect outgroup taxa (monotremes, alligators), showing that the trends we report are posture-independent. These differences support our hypothesis that sub-articular shape scales differently between eutherian mammals and saurischian dinosaurs. Our results show that articular cartilage thickness and sub-articular shape are correlated. In mammals, joints become ever more congruent and thinner with increasing size, whereas archosaur joints remained both congruent and thick, especially in sauropods. We suggest that gigantism occurs less frequently in mammals, in part, because joints composed of thin articular cartilage can only become so congruent before stress cannot be effectively alleviated. In contrast, frequent gigantism in saurischian dinosaurs may be explained, in part, by joints with thick articular cartilage that can deform across large areas with increasing load. PMID:24130690

  20. A Mixed-Ligand Approach for a Gigantic and Hollow Heterometallic Cage {Ni64 RE96 } for Gas Separation and Magnetic Cooling Applications.

    PubMed

    Chen, Wei-Peng; Liao, Pei-Qin; Yu, Youzhu; Zheng, Zhiping; Chen, Xiao-Ming; Zheng, Yan-Zhen

    2016-08-01

    Nanosized aggregations of metal ions shielded by organic ligands possessing both exquisite structural aesthetics and intriguing properties are fundamentally interesting. Three isostructural gigantic transition-metal-rare-earth heterometallic coordination cages are reported, abbreviated as {Ni64 RE96 } (RE=Gd, Dy, and Y) and obtained by a mixed-ligand approach, each possessing a cuboidal framework made of 160 metal ions and a nanosized spherical cavity in the center. Along with the structural novelty, these hollow cages show highly selective adsorptions for CO2 over CH4 or N2 at ambient temperatures. Moreover, the gadolinium analogue exhibits large magnetocaloric effect at ultralow temperatures. PMID:27345594

  1. Nanoscale assemblies of gigantic molecular {Mo154}-rings: (dimethyldioctadecylammonium)20[Mo154O462H8(H2O)70].

    PubMed

    Akutagawa, Tomoyuki; Jin, Reina; Tunashima, Ryo; Noro, Shin-Ichiro; Cronin, Leroy; Nakamura, Takayoshi

    2008-01-01

    Clusters based on the mixed-valence gigantic inorganic ring [Mo154O462H14(H2O)70]14- ({Mo154}-ring) and dimethyldioctadecylammonium (DODA) were combined to form novel molecular assemblies of an inorganic-organic hybrid molecular system as Langmuir-Blodgett (LB) and cast films. (DODA)20[Mo154O462H8(H2O)70] (2) was prepared by cation exchange and was characterized by a combination of thermogravimetry, IR, UV-vis-NIR, 1H NMR, and XRD measurements. The salt 2 was soluble in common organic solvents, and the chemical stability of {Mo154}-ring encapsulated by DODA cationic surfactants in CHCl3 was found to be higher than that of the "native" sodium salt of the {Mo154}-ring in H2O. Uniform spherical vesicle-like molecular assemblies of (DODA)20[Mo154O462H8(H2O)70] were observed in dilute THF, whose average diameter of 95 nm and a normalized variance of 5.7% were confirmed by a X-ray small-angle scattering. Deposition of 2 as a cast film showed circular domains with a typical diameter of approximately 100 nm, indicating possible similarities between solution and surface-deposited structures. The resulting LB films of salt 2 were transferred from an acidic buffer subphase with pH = 1.5 onto mica, giving a two-dimensional film surface with a unity transfer ratio. Further, the electronic absorption spectra of the LB multilayer were consistent with the classic type II mixed-valence MoV/MoVI electronic state well know for molybdenum blue {Mo154}-ring systems, and it appears that on the surface the plane of the {Mo154}-ring is approximately parallel to the substrate surface, as indicated by polarized electronic spectra, while the alkyl chains of DODA were relatively normal to the substrate surface. Therefore, the layer between the {Mo154}-rings and DODA cations was alternately stacked along the direction of film propagation. Finally, it was found that the surface morphology of the cast and LB films was determined by the molecular assembly of (DODA)20[Mo154O462H8(H2O)70] in

  2. Darwin's "Gigantic Blunder."

    ERIC Educational Resources Information Center

    Barrett, Paul H.

    1973-01-01

    Darwin's attempt at unraveling the Glen Roy parallel road mystery is discussed. He admitted that Louis Agassiz's glacier theory seemed reasonable but he was reluctant to give up on his own marine theory. (DF)

  3. No More Gigantism

    ERIC Educational Resources Information Center

    Vohra, B. B.

    1975-01-01

    The food situation in India is critical. It requires the development of both land and water resources, both of which are largely untapped. Ground water is one undeveloped resource that can help alleviate the irrigation problems facing agriculture. More efficient utilization could free millions of hectares of land for cultivation. (MA)

  4. Generation of "gigantic" ultra-short microwave pulses based on passive mode-locking effect in electron oscillators with saturable absorber in the feedback loop

    NASA Astrophysics Data System (ADS)

    Ginzburg, N. S.; Denisov, G. G.; Vilkov, M. N.; Zotova, I. V.; Sergeev, A. S.

    2016-05-01

    A periodic train of powerful ultrashort microwave pulses can be generated in electron oscillators with a non-linear saturable absorber installed in the feedback loop. This method of pulse formation resembles the passive mode-locking widely used in laser physics. Nevertheless, there is a specific feature in the mechanism of pulse amplification when consecutive energy extraction from different fractions of a stationary electron beam takes place due to pulse slippage over the beam caused by the difference between the wave group velocity and the electron axial velocity. As a result, the peak power of generated "gigantic" pulses can exceed not only the level of steady-state generation but also, in the optimal case, the power of the driving electron beam.

  5. A probable case of gigantism/acromegaly in skeletal remains from the Jewish necropolis of "Ronda Sur" (Lucena, Córdoba, Spain; VIII-XII centuries CE).

    PubMed

    Viciano, Joan; De Luca, Stefano; López-Lázaro, Sandra; Botella, Daniel; Diéguez-Ramírez, Juan Pablo

    2015-01-01

    Pituitary gigantism is a rare endocrine disorder caused by hypersecretion of growth hormone during growing period. Individuals with this disorder have an enormous growth in height and associated degenerative changes. The continued hypersecretion of growth hormone during adulthood leads to acromegaly, a condition related to the disproportionate bone growth of the skull, hands and feet. The skeletal remains studied belong to a young adult male from the Jewish necropolis of "Ronda Sur" in Lucena (Córdoba, Spain, VIII-XII centuries CE). The individual shows a very large and thick neurocranium, pronounced supraorbital ridges, an extremely prominent occipital protuberance, and an extremely large and massive mandible. Additional pathologies include enlargement of the vertebral bodies with degenerative changes, thickened ribs, and a slight increased length of the diaphysis with an increased cortical bone thickness of lower limbs. Comparative metric analysis of the mandible with other individuals from the same population and a contemporary Mediterranean population shows a trend toward acromegalic morphology. This case is an important contribution in paleopathological literature because it is a rare condition that has not been widely documented in ancient skeletal remains. PMID:25776010

  6. The very-broad-band long-base tiltmeters of Grotta Gigante (Trieste, Italy): Secular term tilting and the great Sumatra-Andaman islands earthquake of December 26, 2004

    NASA Astrophysics Data System (ADS)

    Braitenberg, Carla; Romeo, Giovanni; Taccetti, Quintilio; Nagy, Ildikò

    2006-01-01

    The horizontal pendulums of the Grotta Gigante (Giant Cave) in the Trieste Karst, are long-base tiltmeters with Zöllner type suspension. The instruments have been continuously recording tilt and shear in the Grotta Gigante since the date of their installation by Prof. Antonio Marussi in 1966. Their setup has been completely overhauled several times since installation, restricting the interruptions of the measurements though to a minimum. The continuous recordings, apart from some interruptions, cover thus almost 40 years of measurements, producing a very noticeable long-term tiltmeter record of crustal deformation. The original recording system, still in function, was photographic with a mechanical timing and paper-advancing system, which has never given any problems at all, as it is very stable and not vulnerable by external factors as high humidity, problems in power supply, lightning or similar. In December 2003 a new recording system was installed, based on a solid-state acquisition system intercepting a laser light reflected from a mirror mounted on the horizontal pendulum beam. The sampling rate is 30 Hz, which turns the long-base instrument to a very-broad-band tiltmeter, apt to record the tilt signal on a broad-band of frequencies, ranging from secular deformation rate through the earth tides to seismic waves. Here we describe the acquisition system and present two endline members of the instrumental observation, the up to date long-term recording, and the observation of the great Sumatra-Andaman Islands earthquake of December 26, 2004, seismic moment magnitude Mw = 9.1-9.3 [Lay, T., Kanamori, H., Ammon, C.J., Nettles, M., Ward, S.N., Aster, R.C., Beck, S.L., Bilek, S.L., Brudzinski, M.L., Butler, R., DeShon, H.R., Ekström, G., Satake, K., Sipkin, S., 2005. The Great Sumatra-Andaman Earthquake of 26 December 2004. Science. 308, 1127-1133.]. The secular-term observations indicate an average tilting over the last four decades towards NW of 23.4 nrad

  7. Ultrafast and Gigantic Spin Injection in Semiconductors

    NASA Astrophysics Data System (ADS)

    Battiato, M.; Held, K.

    2016-05-01

    The injection of spin currents in semiconductors is one of the big challenges of spintronics. Motivated by the ultrafast demagnetization and spin injection into metals, we propose an alternative femtosecond route based on the laser excitation of superdiffusive spin currents in a ferromagnet such as Ni. Our calculations show that even though only a fraction of the current crosses the Ni-Si interface, the laser-induced creation of strong transient electrical fields at a ferromagnet-semiconductor interface allows for the injection of chargeless spin currents with record spin polarizations of 80%. Beyond that they are pulsed on the time scale of 100 fs which opens the door for new experiments and ultrafast spintronics.

  8. Ultrafast and Gigantic Spin Injection in Semiconductors.

    PubMed

    Battiato, M; Held, K

    2016-05-13

    The injection of spin currents in semiconductors is one of the big challenges of spintronics. Motivated by the ultrafast demagnetization and spin injection into metals, we propose an alternative femtosecond route based on the laser excitation of superdiffusive spin currents in a ferromagnet such as Ni. Our calculations show that even though only a fraction of the current crosses the Ni-Si interface, the laser-induced creation of strong transient electrical fields at a ferromagnet-semiconductor interface allows for the injection of chargeless spin currents with record spin polarizations of 80%. Beyond that they are pulsed on the time scale of 100 fs which opens the door for new experiments and ultrafast spintronics. PMID:27232029

  9. Sotos' Syndrome (Cerebral Gigantism) with Peripheral Dysostosis

    PubMed Central

    Evans, P. R.

    1971-01-01

    A girl had short stumpy hands and feet due to osseous dystrophy; in other respects she showed all the main and many of the minor features of Sotos' syndrome during infancy. Then she was on the 97th centile for height, but she grew to be a woman on the 10th centile. Menarche was at 12¾ years; growth in height stopped before 14½ though epiphysial fusion had not occurred; educational difficulties were still being fought at 18 years but she was well adjusted and happy. ImagesFIG. 1FIG. 2FIG. 3 PMID:5089596

  10. A distância e o conteúdo estelar da região HII gigante G333.1-0.4 - vínculos para a taxa de formação estelar da galáxia

    NASA Astrophysics Data System (ADS)

    Figuerêdo, E.; Damineli, A.; Blum, R.; Conti, P.

    2003-08-01

    Neste trabalho apresentamos imagens de alta resolução angular da região HII gigante G333.1-0.4 obtidas através dos filtros J, H e K no telescópio de 4-m do CTIO. Este trabalho faz parte de um estudo de regiões HII gigantes no infravermelho próximo que tem por objetivo estudar a natureza da formação de estrelas massivas e traçar a estrutura espiral de nossa galáxia. Nossa determinação da distância é baseada no método da paralaxe espectroscópica de estrelas OB localizadas na seqüência principal de idade zero (ZAMS) do Diagrama HR. No caso de G333.1-0.4, a magnitude aparente das estrelas localizadas na ZAMS indica que a distância não pode ser maior do que o limite inferior determinado por técnica rádio (2,8 kpc). Resultados semelhantes foram encontrados para regiões estudadas anteriormente, reforçando a idéia de que a taxa de formação estelar na Via Láctea é menor do que o determinado a partir de dados rádio. Nossos resultados mais recentes sobre o conteúdo estelar de G333.1-0.4 revelaram vários objetos que possuem cores bastante avermelhadas (H-K > 2,0). Nós identificamos estes objetos usando os diagramas cor-cor e cor-magnitude dos aglomerados. Estes objetos apresentam um forte excesso em emissão na banda K e possivelmente se tratam de estrelas do tipo OB envolvidas por um disco/envelope circumestelar espesso. O estudo da função de massa inical desta região, em conjunto com resultados de nossos trabalhos anteriores, aponta para uma IMF independente da posição galática. A contagem de estrelas nos fornece um valor para o número de fótons no contínuo de Lyman que corrobora com a afirmação de que G333.1-0.4 se encontra mais próxima da menor distância determinada por rádio.

  11. A Gigantic Anogenital Lesion: Buschke-Lowenstein Tumor

    PubMed Central

    Sandhu, Rikinder; Min, Zaw; Bhanot, Nitin

    2014-01-01

    Buschke-Lowenstein tumor is a relatively rare sexually transmitted disease. It is a neoplasm of the anogenital region which has benign appearance on histopathology but is locally destructive. It carries a high recurrence rate and a significant potential for malignant transformation. Human papilloma virus has been implicated as an etiologic agent for this tumor. Since this disease is rare and no controlled studies exist, radical excision of this anogenital lesion is generally recommended as the first line therapy and close vigilance and followup are essential. We have discussed an overview of etiopathogenesis, clinical presentation, diagnosis, and management of this uncommonly encountered disease. PMID:25431694

  12. Benign or Malignant? Two Case Reports of Gigantic Prostatic Cyst.

    PubMed

    Yu, Jiang; Wang, Xizhi; Luo, Feiye; Wang, Bo; Wang, Yi

    2016-09-01

    A 60-year-old male with a huge prostate cyst presented with obstruction symptom of urethra and intestinal tract. Complete excision of the cystic prostate failed as a result of the strong adherence and twice operations history, but we confirmed prostate adenocarcinoma and relieved his obstruction symptom. Case 2 was a 77-year-old male with an 8 cm cyst of which biopsy showed prostate cancer in local hospital. He was admitted 18 months later because of intestinal obstruction. Radical resection had a satisfied result of obstruction symptom and PSA. Here we summarized malignant characteristics of cystic lesions in prostate or surrounding structures and management. PMID:27500085

  13. Acromegalic gigantism, physicians and body snatching. Past or present?

    PubMed

    de Herder, Wouter W

    2012-09-01

    The skeletons of 2 famous acromegalic giants: Charles Byrne (1761-1783) and Henri Cot = Joseph Dusorc (1883-1912) and the embalmed body of the famous acromegalic giant Édouard Beaupré (1881-1904) all ended up in the medical collections of museums despite the fact that these patients had never donated or even refused to donate their corpses, nor had their relatives given permission. The corpse of the acromegalic giant John Aasen (1890-1938) was voluntarily donated to a physician annex collector of trivia from acromegalic giants. The autopsy on the acromegalic giant John Turner (1874-1911) was performed during his funeral ceremony without the relatives being informed. Only recently, the acromegalic giant Alexander Sizonenko (1959-2012) was made a financial offer during his life in exchange for his body after his death. The case-histories of these 6 patients and also the circumstances that led to the (in-) voluntary donation of their bodies are reviewed. PMID:22481633

  14. Gigantism, temperature and metabolic rate in terrestrial poikilotherms.

    PubMed

    Makarieva, Anastassia M; Gorshkov, Victor G; Li, Bai-Lian

    2005-11-01

    The mechanisms dictating upper limits to animal body size are not well understood. We have analysed body length data for the largest representatives of 24 taxa of terrestrial poikilotherms from tropical, temperate and polar environments. We find that poikilothermic giants on land become two-three times shorter per each 10 degrees of decrease in ambient temperature. We quantify that this diminution of maximum body size accurately compensates the drop of metabolic rate dictated by lower temperature. This supports the idea that the upper limit to body size within each taxon can be set by a temperature-independent critical minimum value of mass-specific metabolic rate, a fall below which is not compatible with successful biological performance. PMID:16191647

  15. Gigantism in unique biogenic magnetite at the Paleocene-Eocene Thermal Maximum.

    PubMed

    Schumann, Dirk; Raub, Timothy D; Kopp, Robert E; Guerquin-Kern, Jean-Luc; Wu, Ting-Di; Rouiller, Isabelle; Smirnov, Aleksey V; Sears, S Kelly; Lücken, Uwe; Tikoo, Sonia M; Hesse, Reinhard; Kirschvink, Joseph L; Vali, Hojatollah

    2008-11-18

    We report the discovery of exceptionally large biogenic magnetite crystals in clay-rich sediments spanning the Paleocene-Eocene Thermal Maximum (PETM) in a borehole at Ancora, NJ. Aside from previously described abundant bacterial magnetofossils, electron microscopy reveals novel spearhead-like and spindle-like magnetite up to 4 microm long and hexaoctahedral prisms up to 1.4 microm long. Similar to magnetite produced by magnetotactic bacteria, these single-crystal particles exhibit chemical composition, lattice perfection, and oxygen isotopes consistent with an aquatic origin. Electron holography indicates single-domain magnetization despite their large crystal size. We suggest that the development of a thick suboxic zone with high iron bioavailability--a product of dramatic changes in weathering and sedimentation patterns driven by severe global warming--drove diversification of magnetite-forming organisms, likely including eukaryotes. PMID:18936486

  16. Gigantism in unique biogenic magnetite at the Paleocene–Eocene Thermal Maximum

    PubMed Central

    Schumann, Dirk; Raub, Timothy D.; Kopp, Robert E.; Guerquin-Kern, Jean-Luc; Wu, Ting-Di; Rouiller, Isabelle; Smirnov, Aleksey V.; Sears, S. Kelly; Lücken, Uwe; Tikoo, Sonia M.; Hesse, Reinhard; Kirschvink, Joseph L.; Vali, Hojatollah

    2008-01-01

    We report the discovery of exceptionally large biogenic magnetite crystals in clay-rich sediments spanning the Paleocene–Eocene Thermal Maximum (PETM) in a borehole at Ancora, NJ. Aside from previously described abundant bacterial magnetofossils, electron microscopy reveals novel spearhead-like and spindle-like magnetite up to 4 μm long and hexaoctahedral prisms up to 1.4 μm long. Similar to magnetite produced by magnetotactic bacteria, these single-crystal particles exhibit chemical composition, lattice perfection, and oxygen isotopes consistent with an aquatic origin. Electron holography indicates single-domain magnetization despite their large crystal size. We suggest that the development of a thick suboxic zone with high iron bioavailability—a product of dramatic changes in weathering and sedimentation patterns driven by severe global warming—drove diversification of magnetite-forming organisms, likely including eukaryotes. PMID:18936486

  17. Supercontinental warming of the mantle at the origin of gigantic flood basalts

    NASA Astrophysics Data System (ADS)

    Coltice, N.; Phillips, B. R.; Bertrand, H.; Ricard, Y.; Rey, P.

    2006-12-01

    Continents episodically cluster together into a supercontinent, eventually breaking up with intense magmatic activity supposedly causedby mantle plumes. The break-up of Pangea, the last supercontinent, was accompanied by the emplacement of the largest known continental flood basalt, the Central Atlantic Magmatic Province, causing massive extinctions at the Triassic/Jurassic boundary. However, there is little support for a plume origin for this catastrophic event. On the basis of 2D and 3D spherical convection modelling in a internally heated mantle, we show that continental aggregation leads to large-scale melting without requiring the involvement of plumes. When only internal heat sources in the mantle are considered, the formationof a supercontinent causes the enlargement of the wavelength of the flow and a subcontinental warming as large as 100^{\\mboxo}C. This temperature increase may lead to large- scale melting without the involvment of plumes. Our results suggest the existence of two distinct types of continental flood basalts, caused by plume or by supercontinental warming. We review some potential candidates for our proposed model.

  18. A Gigantic Shark from the Lower Cretaceous Duck Creek Formation of Texas

    PubMed Central

    Frederickson, Joseph A.; Schaefer, Scott N.; Doucette-Frederickson, Janessa A.

    2015-01-01

    Three large lamniform shark vertebrae are described from the Lower Cretaceous of Texas. We interpret these fossils as belonging to a single individual with a calculated total body length of 6.3 m. This large individual compares favorably to another shark specimen from the roughly contemporaneous Kiowa Shale of Kansas. Neither specimen was recovered with associated teeth, making confident identification of the species impossible. However, both formations share a similar shark fauna, with Leptostyrax macrorhiza being the largest of the common lamniform sharks. Regardless of its actual identification, this new specimen provides further evidence that large-bodied lamniform sharks had evolved prior to the Late Cretaceous. PMID:26039066

  19. High-level organization of isochores into gigantic superstructures in the human genome

    NASA Astrophysics Data System (ADS)

    Carpena, P.; Oliver, J. L.; Hackenberg, M.; Coronado, A. V.; Barturen, G.; Bernaola-Galván, P.

    2011-03-01

    Human DNA shows a complex structure with compositional features at many scales; the isochores—long DNA segments (~105 bp) of relatively homogeneous guanine-cytosine (G + C) content—are the largest well-documented and well-analyzed compositional structures. However, we report here on the existence of a high-level compositional organization of isochores in the human genome. By using a segmentation algorithm incorporating the long-range correlations existing in human DNA, we find that every chromosome is composed of a few huge segments (~ 107 bp) of relatively homogeneous G + C content, which become the largest compositional organization of the genome. Finally, we show evidence of the biological relevance of these superstructures, pointing to a large-scale functional organization of the human genome.

  20. Low-magnesium uranium-calcite with high degree of crystallinity and gigantic luminescence emission.

    PubMed

    Valle-Fuentes, Francisco-Jose; Garcia-Guinea, Javier; Cremades, Ana; Correcher, Virgilio; Sanchez-Moral, Sergio; Gonzalez-Martin, Rafael; Sanchez-Muñoz, Luis; Lopez-Arce, Paula

    2007-01-01

    Cabrera (Madrid) low-Mg calcites exhibit: (i) an unusual twofold elevation in X-ray diffraction pattern intensity; (ii) a 60-fold elevation of luminescence emission, compared to six common natural calcites selected for comparison purposes; (iii) a natural relatively high radiation level of circa 200 nSvh(-1) not detected in 1300 other calcites from the Natural History Museum of Madrid. Calcites were analysed by the X-ray diffraction powder method (XRD), cathodo-luminescence spectroscopy in scanning electron microscopy (CL-SEM), thermoluminescence (TL), differential thermal analysis (DTA), X-ray fluorescence spectrometry (XRF) and particle size distribution (PSD). The Cabrera calcite study shows: (i) helicoidally distributed steps along the (0001) orientation; (ii) protuberance defects onto the (0001) surface, observed by SEM; (iii) XRF chemical contents of 0.03% MgO, 0.013% of Y(2)O(3), and 0.022% of U(3)O(8), with accessory amounts of rare earth elements (REE); (iv) DTA dissociation temperature of 879 degrees C; (v) TL maxima peaks at 233 and 297 degrees C whose areas are 60 times compared to other calcites; (vi) spectra CL-SEM bands at 2.0 and 3.4 eV in the classic structure of Mn(2+) activators; (vii) a twofold XRD pattern explained given that sample is a low-Mg calcite. The huge TL and CL emissions of the Cabrera calcite sample must be linked with the uranyl group presence. This intense XRD pattern in low-Mg calcites could bring into being analytical errors. PMID:17011199

  1. A gigantic shark from the lower cretaceous duck creek formation of Texas.

    PubMed

    Frederickson, Joseph A; Schaefer, Scott N; Doucette-Frederickson, Janessa A

    2015-01-01

    Three large lamniform shark vertebrae are described from the Lower Cretaceous of Texas. We interpret these fossils as belonging to a single individual with a calculated total body length of 6.3 m. This large individual compares favorably to another shark specimen from the roughly contemporaneous Kiowa Shale of Kansas. Neither specimen was recovered with associated teeth, making confident identification of the species impossible. However, both formations share a similar shark fauna, with Leptostyrax macrorhiza being the largest of the common lamniform sharks. Regardless of its actual identification, this new specimen provides further evidence that large-bodied lamniform sharks had evolved prior to the Late Cretaceous. PMID:26039066

  2. Gigantism in honeybees: Apis cerana queens reared in mixed-species colonies

    NASA Astrophysics Data System (ADS)

    Tan, Ken; Hepburn, H. R.; He, Shaoyu; Radloff, S. E.; Neumann, P.; Fang, Xiang

    2006-07-01

    The development of animals depends on both genetic and environmental effects to a varying extent. Their relative influences can be evaluated in the social insects by raising the intracolonial diversity to an extreme in nests consisting of workers from more than one species. In this study, we studied the effects of mixed honeybee colonies of Apis mellifera and Apis cerana on the rearing of grafted queen larvae of A. cerana. A. mellifera sealed worker brood was introduced into A. cerana colonies and on emergence, the adults were accepted. Then, A. cerana larvae were grafted for queen rearing into two of these mixed-species colonies. Similarly, A. cerana larvae and A. mellifera larvae were also grafted conspecifically as controls. The success rate of A. cerana queen rearing in the test colonies was 64.5%, surpassing all previous attempts at interspecific queen rearing. After emergence, all virgin queens obtained from the three groups ( N=90) were measured morphometrically. The A. cerana queens from the mixed-species colonies differed significantly in size and pigmentation from the A. cerana control queens and closely approximated the A. mellifera queens. It is inferred that these changes in the A. cerana queens reared in the mixed-species colonies can be attributed to feeding by heterospecific nurse bees and/or chemical differences in royal jelly. Our data show a strong impact of environment on the development of queens. The results further suggest that in honeybees the cues for brood recognition can be learned by heterospecific workers after eclosion, thereby providing a novel analogy to slave making in ants.

  3. Gigantic optical nonlinearity in one-dimensional Mott-Hubbard insulators

    PubMed

    Kishida; Matsuzaki; Okamoto; Manabe; Yamashita; Taguchi; Tokura

    2000-06-22

    The realization of all-optical switching, modulating and computing devices is an important goal in modern optical technology. Nonlinear optical materials with large third-order nonlinear susceptibilities (chi(3)) are indispensable for such devices, because the magnitude of this quantity dominates the device performance. A key strategy in the development of new materials with large nonlinear susceptibilities is the exploration of quasi-one-dimensional systems, or 'quantum wires'--the quantum confinement of electron-hole motion in one-dimensional space can enhance chi(3). Two types of chemically synthesized quantum wires have been extensively studied: the band insulators of silicon polymers, and Peierls insulators of pi-conjugated polymers and platinum halides. In these systems, chi(3) values of 10(-12) to 10(-7) e.s.u. (electrostatic system of units) have been reported. Here we demonstrate an anomalous enhancement of the third-order nonlinear susceptibility in a different category of quantum wires: one-dimensional Mott insulators of 3d transition-metal oxides and halides. By analysing the electroreflectance spectra of these compounds, we measure chi(3) values in the range 10(-8) to 10(-5) e.s.u. The anomalous enhancement results from a large dipole moment between the lowest two excited states of these systems. PMID:10879529

  4. Alcohol chemistry in the Galactic Center molecular clouds. A gigantic Hot Core

    NASA Astrophysics Data System (ADS)

    Requena Torres, M. A.; Martín-Pintado, J.; Rodríguez-Franco, A.; Martín, S.; Rodríguez-FerńNdez, N. J.

    We have carried out a systematic study of CH3OH, C2H5OH, (CH3)2O, HCOOCH3, HCOOH, CH3COOH, H2CO and CS in different Galactic Center (GC) molecular clouds. Figure 1 shows the relative abundances of those molecules with respect to CH3OH in the GC as function of the CH3OH abundance. The CH3OH abundance between sources in the GC varies in nearly two orders of magnitude. The abundance ratio of these molecules relative to CH3OH is basically independent of the CH3OH abundances and only varies in a factor of ~ 4 - 8. The abundance ratio of CS relative to CH3OH seem to vary by a factor of 60. Our data are compared with observations of the same molecules in short-lived objects like the hot cores. The abundance and the abundance ratios of the complex molecules relative to CH3OH in massive hot cores are similar to that found in the GC clouds. Alcohol related chemistry is believed to be driven by gas phase reactions after evaporation of alcohols from grain mantles. Gas phase chemistry based in the ejection of alcohols from grains (see Charnley et al. 1995; Horn et al. (2004)) can not explain the observed abundances of HCOOCH3 in the GC and the rather constant relative abundances of the other complex molecules. Our data suggest that basically all the molecules related to alcohol chemistry could be produced on grain mantles and/or depleted from gas phase after their formation. This interpretation requires frequent shocks in the GC region to keep the high abundances of these molecules in gas phase and a rather uniform average composition of the icy grain mantles. The molecular clouds associated with the Sickle and the Thermal Radio Arches (TRA), which seem to be affected by UV radiation, see Rodriguez-Fernandez et al. (2001), show lower abundances of C2H5OH relative to CH3OH which could be explained by shock ejection and photo dissociation conditions.

  5. The Battle of the Pronouns: Gigantic Clashes in a Book of Dinasaur Riddles.

    ERIC Educational Resources Information Center

    Sterne, Noelle

    1981-01-01

    The author of "Tyrannosaurus Wrecks: A Book of Dinosaur Riddles" discusses her difficulties in choosing appropriate male-female pronouns for the subjects of her riddles. The problems consisted of the necessity of using entrenched male stereotypes, avoiding damaging female stereotypes, and breaking through stereotypes. (KC)

  6. Discovery of the Largest Orbweaving Spider Species: The Evolution of Gigantism in Nephila

    PubMed Central

    Kuntner, Matjaž; Coddington, Jonathan A.

    2009-01-01

    Background More than 41,000 spider species are known with about 400–500 added each year, but for some well-known groups, such as the giant golden orbweavers, Nephila, the last valid described species dates from the 19th century. Nephila are renowned for being the largest web-spinning spiders, making the largest orb webs, and are model organisms for the study of extreme sexual size dimorphism (SSD) and sexual biology. Here, we report on the discovery of a new, giant Nephila species from Africa and Madagascar, and review size evolution and SSD in Nephilidae. Methodology We formally describe N. komaci sp. nov., the largest web spinning species known, and place the species in phylogenetic context to reconstruct the evolution of mean size (via squared change parsimony). We then test female and male mean size correlation using phylogenetically independent contrasts, and simulate nephilid body size evolution using Monte Carlo statistics. Conclusions Nephila females increased in size almost monotonically to establish a mostly African clade of true giants. In contrast, Nephila male size is effectively decoupled and hovers around values roughly one fifth of female size. Although N. komaci females are the largest Nephila yet discovered, the males are also large and thus their SSD is not exceptional. PMID:19844575

  7. Hard magnetic ferrite with a gigantic coercivity and high frequency millimetre wave rotation

    PubMed Central

    Namai, Asuka; Yoshikiyo, Marie; Yamada, Kana; Sakurai, Shunsuke; Goto, Takashi; Yoshida, Takayuki; Miyazaki, Tatsuro; Nakajima, Makoto; Suemoto, Tohru; Tokoro, Hiroko; Ohkoshi, Shin-ichi

    2012-01-01

    Magnetic ferrites such as Fe3O4 and Fe2O3 are extensively used in a range of applications because they are inexpensive and chemically stable. Here we show that rhodium-substituted ε-Fe2O3, ε-RhxFe2−xO3 nanomagnets prepared by a nanoscale chemical synthesis using mesoporous silica as a template, exhibit a huge coercive field (Hc) of 27 kOe at room temperature. Furthermore, a crystallographically oriented sample recorded an Hc value of 31 kOe, which is the largest value among metal-oxide-based magnets and is comparable to those of rare-earth magnets. In addition, ε-RhxFe2−xO3 shows high frequency millimetre wave absorption up to 209 GHz. ε-Rh0.14Fe1.86O3 exhibits a rotation of the polarization plane of the propagated millimetre wave at 220 GHz, which is one of the promising carrier frequencies (the window of air) for millimetre wave wireless communications. PMID:22948817

  8. Gigantic unruptured sinus of Valsalva aneurysm presenting as an incidental murmur.

    PubMed

    Yagoub, Hatim; Srinivas, Bhanu Prakash; McCarthy, James; Kiernan, Thomas John

    2012-01-01

    We report a case of a 56-year-old man referred by his family physician with an asymptomatic cardiac murmur. Trans-thoracic echocardiography (TTE) suggested an unruptured right sinus of Valsalva aneurysm (SVA) causing extrinsic compression of the right ventricular outflow tract. This was confirmed with an ECG-gated cardiac CT showing a large right SVA measuring 35×37×42 mm in size. Coronary angiography demonstrated non-obstructive coronary artery disease. Ascending thoracic anterior in the right anterior oblique view delineated the right SVA. The patient underwent aortic valve sparing surgical repair of the aneurysm with an excellent result. Echocardiography confirmed obliteration of the aneurysm and normal aortic valve function postoperatively. PMID:23008378

  9. A step to the gigantic genome of the desert locust: chromosome sizes and repeated DNAs.

    PubMed

    Camacho, J P M; Ruiz-Ruano, F J; Martín-Blázquez, R; López-León, M D; Cabrero, J; Lorite, P; Cabral-de-Mello, D C; Bakkali, M

    2015-06-01

    The desert locust (Schistocerca gregaria) has been used as material for numerous cytogenetic studies. Its genome size is estimated to be 8.55 Gb of DNA comprised in 11 autosomes and the X chromosome. Its X0/XX sex chromosome determinism therefore results in females having 24 chromosomes whereas males have 23. Surprisingly, little is known about the DNA content of this locust's huge chromosomes. Here, we use the Feulgen Image Analysis Densitometry and C-banding techniques to respectively estimate the DNA quantity and heterochromatin content of each chromosome. We also identify three satellite DNAs using both restriction endonucleases and next-generation sequencing. We then use fluorescent in situ hybridization to determine the chromosomal location of these satellite DNAs as well as that of six tandem repeat DNA gene families. The combination of the results obtained in this work allows distinguishing between the different chromosomes not only by size, but also by the kind of repetitive DNAs that they contain. The recent publication of the draft genome of the migratory locust (Locusta migratoria), the largest animal genome hitherto sequenced, invites for sequencing even larger genomes. S. gregaria is a pest that causes high economic losses. It is thus among the primary candidates for genome sequencing. But this species genome is about 50 % larger than that of L. migratoria, and although next-generation sequencing currently allows sequencing large genomes, sequencing it would mean a greater challenge. The chromosome sizes and markers provided here should not only help planning the sequencing project and guide the assembly but would also facilitate assigning assembled linkage groups to actual chromosomes. PMID:25472934

  10. Gigantic Ordovician volcanic ash fall in North America and Europe: Biological, tectonomagmatic, and event-stratigraphic significance

    SciTech Connect

    Huff, W.D. ); Bergstroem, S.M. ); Kolata, D.R. )

    1992-10-01

    Biostratigraphical, geochemical, isotopic, and paleogeographic data suggest that the Millbrig K-bentonite, one of the thickest and most widespread Ordovician volcanic ash beds in eastern North America, is the same as the so-called 'Big Bentonite' in Baltoscandia. This is the first time that the same K-bentonite has been identified in both North America and Europe, and it serves as a unique event-stratigraphic marker over a large portion of the Northern Hemisphere. This eruption produced at least 340 km[sup 3] of dense-rock-equivalent ash that was deposited in a layer up to 1-2 m thick over several million square kilometers. As much as 800 km[sup 3] of additional ash may have fallen into the Iapetus Ocean, for a total of 1,140 km[sup 3]. Trace element geochemistry shows that the ash was derived from a felsic calc-alkalic magmatic source characteristic of volcanism in a continental crust-based, destructive plate-margin setting. This is one of the largest, if not the largest, ash falls recorded in Earth's Phanerozoic stratigraphic record, but its recognizable effect on faunas and floras was minimal, and it did not result in a global extinction event. The Millbrig-Big Bentonite bed provides accurate time control for sedimentologic, paleoecologic, and paleogeographic reconstructions across plates positioned in tropical (Laurentia) and temperate (Baltica) latitudes during Middle Ordovician time.

  11. Gigantic enhancement in response and reset time of ZnO UV nanosensor by utilizing Schottky contact and surface functionalization

    PubMed Central

    Zhou, Jun; Gu, Yudong; Hu, Youfan; Mai, Wenjie; Yeh, Ping-Hung; Bao, Gang; Sood, Ashok K.; Polla, Dennis L.; Wang, Zhong Lin

    2009-01-01

    UV response of ZnO nanowire nanosensor has been studied under ambient condition. By utilizing Schottky contact instead of Ohmic contact in device fabrication, the UV sensitivity of the nanosensor has been improved by four orders of magnitude, and the reset time has been drastically reduced from ∼417 to ∼0.8 s. By further surface functionalization with function polymers, the reset time has been reduced to ∼20 ms even without correcting the electronic response of the measurement system. These results demonstrate an effective approach for building high response and fast reset UV detectors. PMID:19654881

  12. A Gigantic Sarcopterygian (Tetrapodomorph Lobe-Finned Fish) from the Upper Devonian of Gondwana (Eden, New South Wales, Australia)

    PubMed Central

    Young, Ben; Dunstone, Robert L.; Senden, Timothy J.; Young, Gavin C.

    2013-01-01

    Edenopteron keithcrooki gen. et sp. nov. is described from the Famennian Worange Point Formation; the holotype is amongst the largest tristichopterids and sarcopterygians documented by semi-articulated remains from the Devonian Period. The new taxon has dentary fangs and premaxillary tusks, features assumed to be derived for large Northern Hemisphere tristichopterids (Eusthenodon, Hyneria, Langlieria). It resembles Eusthenodon in ornament, but is distinguished by longer proportions of the parietal compared to the post-parietal shield, and numerous differences in shape and proportions of other bones. Several characters (accessory vomers in the palate, submandibulars overlapping ventral jaw margin, scales ornamented with widely-spaced deep grooves) are recorded only in tristichopterids from East Gondwana (Australia-Antarctica). On this evidence Edenopteron gen. nov. is placed in an endemic Gondwanan subfamily Mandageriinae within the Tristichopteridae; it differs from the nominal genotype Mandageria in its larger size, less pointed skull, shape of the orbits and other skull characters. The hypothesis that tristichopterids evolved in Laurussia and later dispersed into Gondwana, and a derived subgroup of large Late Devonian genera dispersed from Gondwana, is inconsistent with the evidence of the new taxon. Using oldest fossil and most primitive clade criteria the most recent phylogeny resolves South China and Gondwana as areas of origin for all tetrapodomorphs. The immediate outgroup to tristichopterids remains unresolved – either Spodichthys from Greenland as recently proposed, or Marsdenichthys from Gondwana, earlier suggested to be the sister group to all tristichopterids. Both taxa combine two characters that do not co-occur in other tetrapodomorphs (extratemporal bone in the skull; non-cosmoid round scales with an internal boss). Recently both ‘primitive’ and ‘derived’ tristichopterids have been discovered in the late Middle Devonian of both hemispheres, implying extensive ghost lineages within the group. Resolving their phylogeny and biogeography will depend on a comprehensive new phylogenetic analysis. PMID:23483884

  13. The Pulpí gigantic geode (Almería, Spain): geology, metal pollution, microclimatology, and conservation

    NASA Astrophysics Data System (ADS)

    Fernández-Cortés, Ángel; Calaforra, José María; García-Guinea, Javier

    2006-07-01

    The discovery of the giant Geode of Pulpí (Almería, Spain) was considered as an important highlight in the geological heritage of Spain. Projects developed for their conservation were immediately initiated with legal figures of protection and tourist projects. The Geode has a tourist interest, which must be tempered by environmental restrictions limiting the public visits. First results demonstrate that a continuous visit of two or three people for more than 10 min provokes the appearance of condensation and risks corrosion of the gypsum crystals. In addition, the electron microprobe analyses confirms (1) the hydrothermal phases of iron-manganese in carbonated host rock; (2) the presence of sulphides with Fe-Zn-Pb-Ag-Sb-Cu-Hg-As-Te-Se; and (3) Ba, Ca, and Sr sulphates with mercury traces. The present proposal to label the geode and the mining environment as geological-natural heritage is feasible, although any tourist adaptation must not permit visits to the geode indoor and Hg levels must be controlled.

  14. Ultrafast gigantic photo-response in (EDO-TTF)2PF6 initiated by 10-fs laser pulses

    SciTech Connect

    Schoenlein, Robert William; Itatani, Jiro; Rini, Matteo; Cavalleri, Andrea; Onda, Ken; Ishikawa, Tadahiko; Koshihara, Shin-ya; Shao, Xiangfeng; Yamochi, Hideki; Saito, Gunzi; Schoenlein, Robert W.

    2006-08-07

    We photo-exited a charge-ordered organic salt (EDO-TTF)2PF6 with sub-10-fs optical pulses. The photo-induced metallic phase appeared within 80-fs after pumping, characterized by large changes in reflectivity (DELTA R/R~0.8) followed by strong coherent phonon modulation

  15. Oceanic ecosystem dynamics during gigantic volcanic episodes: the Ontong Java and Manihiki Plateaus recorded by calcareous nannoplankton. (Invited)

    NASA Astrophysics Data System (ADS)

    Erba, E.

    2010-12-01

    Earth's volcanic activity introduces environmental stress that biota are forced to survive. There is a general consensus on the role of volcanogenic carbon dioxide increases, and implicit tectonic-igneous events, triggering major climate changes and profound variations in chemical, physical and trophic characteristics of the oceans through the Phanerozoic. Cretaceous geological records indicate conditions of excess atmCO2 (up to 2000-3000 ppm) derived from construction of Large Igneous Provinces (LIPs). In such “high CO2 world” and greenhouse conditions, the deep ocean became depleted of oxygen promoting the accumulation and burial of massive amounts of organic matter; such episodes are recognized as Oceanic Anoxic Events (OAEs) and their geological records merit careful examination of how the Earth system, and Life in particular, can overcome extreme experiments of global change. The Early Aptian (˜ 120 million years ago) OAE1a is a complex example of volcanicCO2-induced environmental stress. There is a general consensus on the causes of this case-history, namely excess CO2 derived from the construction of the Ontong Java-Manihiki LIP. Multi- and inter-disciplinary studies of the OAE1a have pointed out C, O, Os, Sr isotopic anomalies, a biocalcification crisis in pelagic and neritic settings, enhanced fertility and primary productivity, as well as ocean acidification. Available cyclochronology allows high-resolution dating of biotic and environmental fluctuations, providing the precision necessary for understanding the role of volcanogenic CO2 on nannoplankton biocalcification, adaptations, evolutionary innovation and/or extinctions. The reconstructed sequence of volcanogenic CO2 pulses, and perhaps some clathrate melting, triggered a climate change to supergreenhouse conditions, anoxia and ocean acidification. The demise of heavily calcified nannoconids and reduced calcite paleofluxes marks beginning of the pre-OAE1a calcification crisis. Ephemeral coccolith dwarfism and malformation represent adjustments to survive lower pH. Deep-water acidification occurs with a delay of 25-30 thousand years: a dissolution event recording 1 to 2km shallowing of the Calcite Compensation Depth anticipated the onset of anoxic sedimentation. A major acceleration in weathering has been identified in the lowermost part of OAE1a. After acidification-dissolution climax, nannoplankton and carbonate recovery developed over ~160 kyr, under persisting global dysoxia-anoxia. This recovery presumably implies a stasis of the LIP activity and gradual buffering of ocean acidification or a decrease in volcanogenic CO2 emissions and consistently higher CO2 drawdown through Corg burial and/or weathering. Rising CO2 and surface-ocean acidification during OAE1a triggered false extinctions among calcareous nannoplankton. Conversely, a major origination episode starts approximately 1 My before global anoxia and persists through OAE1a and associated acidification. Increasing pCO2 caused complex and species-specific reactions, including production of r-strategist taxa, which, however, secreted dwarf and malformed coccoliths as a strategy to overcome acidification.

  16. A gigantic sarcopterygian (tetrapodomorph lobe-finned fish) from the upper Devonian of Gondwana (Eden, New South Wales, Australia).

    PubMed

    Young, Ben; Dunstone, Robert L; Senden, Timothy J; Young, Gavin C

    2013-01-01

    Edenopteron keithcrooki gen. et sp. nov. is described from the Famennian Worange Point Formation; the holotype is amongst the largest tristichopterids and sarcopterygians documented by semi-articulated remains from the Devonian Period. The new taxon has dentary fangs and premaxillary tusks, features assumed to be derived for large Northern Hemisphere tristichopterids (Eusthenodon, Hyneria, Langlieria). It resembles Eusthenodon in ornament, but is distinguished by longer proportions of the parietal compared to the post-parietal shield, and numerous differences in shape and proportions of other bones. Several characters (accessory vomers in the palate, submandibulars overlapping ventral jaw margin, scales ornamented with widely-spaced deep grooves) are recorded only in tristichopterids from East Gondwana (Australia-Antarctica). On this evidence Edenopteron gen. nov. is placed in an endemic Gondwanan subfamily Mandageriinae within the Tristichopteridae; it differs from the nominal genotype Mandageria in its larger size, less pointed skull, shape of the orbits and other skull characters. The hypothesis that tristichopterids evolved in Laurussia and later dispersed into Gondwana, and a derived subgroup of large Late Devonian genera dispersed from Gondwana, is inconsistent with the evidence of the new taxon. Using oldest fossil and most primitive clade criteria the most recent phylogeny resolves South China and Gondwana as areas of origin for all tetrapodomorphs. The immediate outgroup to tristichopterids remains unresolved - either Spodichthys from Greenland as recently proposed, or Marsdenichthys from Gondwana, earlier suggested to be the sister group to all tristichopterids. Both taxa combine two characters that do not co-occur in other tetrapodomorphs (extratemporal bone in the skull; non-cosmoid round scales with an internal boss). Recently both 'primitive' and 'derived' tristichopterids have been discovered in the late Middle Devonian of both hemispheres, implying extensive ghost lineages within the group. Resolving their phylogeny and biogeography will depend on a comprehensive new phylogenetic analysis. PMID:23483884

  17. Sistema Solar: de la observación de La Tierra a los planetas gigantes y sus lunas

    NASA Astrophysics Data System (ADS)

    Rodrigo, R.

    La fotoquímica tiene un papel principal en la composición de las atmósferas planetarias. Se examinan diferentes procesos fotoquímicos tanto para atmósferas oxidadas como reductoras, poniendo un especial énfasis en los ciclos químicos más importantes. En este sentido, se presentan diferentes ciclos químicos capaces de producir hidrocarbonos y nitrilos en atmósferas reductoras, así como aquellos capaces de mantener las proporciones de mezcla de las moléculas que contienen oxígeno, tales como CO2, O2 y H2O. También se analizan otros procesos importantes tales como la condensación y procesos de sputtering y de sublimación que han de tenerse en cuenta cuando se realizan modelos sobre la composición atmosférica.

  18. From Ally McBeal to Sabado Gigante: Contributions of Television Viewing to the Gender Role Attitudes of Latino Adolescents

    ERIC Educational Resources Information Center

    Rivadeneyra, Rocio; Ward, L. Monique

    2005-01-01

    Although previous findings indicate that frequent television viewing is associated with holding more stereotypical attitudes about gender, no studies have examined this connection among Latino youth, who are frequent viewers of both English- and Spanish-language programming. The present study attempted to rectify this situation by examining…

  19. Gigantism in a Bacterium, Epulopiscium fishelsoni, Correlates with Complex Patterns in Arrangement, Quantity, and Segregation of DNA

    PubMed Central

    Bresler, V.; Montgomery, W. L.; Fishelson, L.; Pollak, P. E.

    1998-01-01

    Epulopiscium fishelsoni, gut symbiont of the brown surgeonfish (Acanthurus nigrofuscus) in the Red Sea, attains a larger size than any other eubacterium, varies 10- to 20-fold in length (and >2,000-fold in volume), and undergoes a complex daily life cycle. In early morning, nucleoids contain highly condensed DNA in elongate, chromosome-like structures which are physically separated from the general cytoplasm. Cell division involves production of two (rarely three) nucleoids within a cell, deposition of cell walls around expanded nucleoids, and emergence of daughter cells from the parent cell. Fluorescence measurements of DNA, RNA, and other cell components indicate the following. DNA quantity is proportional to cell volume over cell lengths of ∼30 μm to >500 μm. For cells of a given size, nucleoids of cells with two nucleoids (binucleoid) contain approximately equal amounts of DNA. And each nucleoid of a binucleoid cell contains one-half the DNA of the single nucleoid in a uninucleoid cell of the same size. The life cycle involves approximately equal subdivision of DNA among daughter cells, formation of apical caps of condensed DNA from previously decondensed and diffusely distributed DNA, and “pinching” of DNA near the middle of the cell in the absence of new wall formation. Mechanisms underlying these patterns remain unclear, but formation of daughter nucleoids and cells occurs both during diurnal periods of host feeding and bacterial cell growth and during nocturnal periods of host inactivity when mean bacterial cell size declines. PMID:9791108

  20. Dual electron-phonon coupling model for gigantic photoenhancement of the dielectric constant and electronic conductivity in SrTi O3

    NASA Astrophysics Data System (ADS)

    Qiu, Y.; Wu, C. Q.; Nasu, K.

    2005-12-01

    In connection with the recent experimental discovery on photoenhancements of the electronic conductivity and the quasi-static electric susceptibility in SrTiO3 , we theoretically study a photogeneration mechanism of charged and conductive ferroelectric domains in this perovskite type quantum dielectric. The photo-generated electron, being quite itinerant in the 3d band of Ti4+ , is assumed to couple weakly but quadratically with soft-anharmonic T1u phonons in this quantum dielectric, in view of the parity of this lattice vibration. The photo-generated electron is also assumed to couple strongly but linearly with the breathing type high energy phonons. Using a tight-binding model for electrons, we will show that this dual electron-phonon coupling results in two types of polarons, a “super-para-electric (SPE) large polaron” with a quasi-globle parity violation, and an “off-center type self-trapped polaron” with only a local parity violation. This SPE large polaron is shown to be equal to a singly charged (e-) and conductive ferroelectric domain with a quasi-macroscopic range. Two of such large polarons are shown to aggregate and form an SPE large bipolaron, which is still conductive. Various other bipolaron clusters are also shown to be formed in this electron-phonon coupled system. These large polarons have a high mobility and an enhanced quasi-static dielectric susceptibility. Effect of adulteration is also discussed.

  1. Replacement of wheat bran with spineless cactus (Opuntia ficus indica Mill cv Gigante) and urea in the diets of Holstein x Gyr heifers.

    PubMed

    de Figueiredo Monteiro, Carolina Corrêa; Silva de Melo, Airon Aparecido; Ferreira, Marcelo Andrade; de Souza Campos, José Mauricio; Rodrigues Souza, Julyana Sena; Dos Santos Silva, Evannielly Thuanny; de Paula Xavier de Andrade, Rafael; da Silva, Emmanuelle Cordeiro

    2014-10-01

    The aim of this study was to evaluate the replacement effect of wheat bran with spineless cactus and urea in heifers. Twenty-four heifers with an average initial weight of 185 ± 13 kg were used in this experiment. Four levels of spineless cactus corrected with urea and ammonium sulfate (9:1) were studied: 0, 33, 66, and 100 % replacement with wheat bran. Samples of feed, orts, and feces were analyzed to estimate the intake and digestibility of dry matter (DM) and nutrients. Indigestible neutral detergent fiber was used as an internal marker. The experiment was conducted in a completely randomized design. Dry matter, neutral detergent fiber, and total digestible nutrient intake demonstrated a quadratic effect (P < 0.05). Rumen degradable protein intake increased linearly (P < 0.05). The maximum DM digestibility was estimated to be 0.67 with a 43 % replacement. Crude protein and NDF digestibility increased linearly (P < 0.05). The total body weight gain and average daily gain decreased linearly with the replacement. Thus, it is practical to replace wheat bran with spineless cactus containing urea and ammonium sulfate up to 66 % in sugar cane-based diets. PMID:24839899

  2. Detecção da fase impulsiva de uma explosão solar gigante até 405 GHz

    NASA Astrophysics Data System (ADS)

    Raulin, J.-P.; Makhmutov, V.; Kaufmann, P.; Pacini, A. A.; Luethi, T.; Hudson, H. S.; Gary, D. E.; Yoshimori, M.

    2003-08-01

    A explosão ocorrida no dia 25/08/2001 foi uma das mais intensas do presente ciclo solar em ondas de rádio de altas frequências. Foram medidas em ondas milimétricas e submilimétricas, aproximadamente, 105 e vários milhares de unidades de fluxo solar, respectivamente. Apresentamos um estudo deste evento em múltiplas frequências, desde microondas (1GHz), até ondas submilimétricas (405 GHz) detectadas pelo Telescópio Solar para ondas Submilimétricas (SST). Esta base de dados foi complementada utilizando-se o experimento Yohkoh, incluindo a emissão em raios-X duros e raios-g (até 100 MeV), e imagens em raios-X moles da região ativa envolvida. Enfocamos e discutimos principalmente os seguintes aspectos da fase impulsiva do evento: (i) as implicações deduzidas do espectro eletromagnético, obtido pela primeira vez até 405 GHz; (ii) a dinâmica da região ativa. Os resultados mostram que para explicar o espectro rádio observado, são necessários entre 3.5×1037 e 1.5×1039 elétrons acelerados acima de 20 keV em uma região de campo magnético entre 300 e 800 Gauss. A estimativa do fluxo de fótons que seria produzido por estes elétrons, mostra que grande parte deles não precipitou na baixa atmosfera. A evolução temporal da emissão em raios-X moles revela que a configuração magnética da região ativa foi muito dinâmica durante a fase impulsiva da explosão. Em particular, mostramos que a produção dos elétrons altamente energéticos foi iniciada junto com a aparição, na baixa coroa solar, de um novo sistema compacto de estruturas magnéticas. Este fato sugere que os locais de aceleração estão localizados na baixa atmosfera do Sol, como resultado da interação entre o novo sistema compacto e o campo magnético ambiente da região ativa.

  3. The electromagnetic Ram action of the plasma focus as a paradigm for the generation of cosmic rays and the gigantic jets in active galaxies

    NASA Astrophysics Data System (ADS)

    Bostick, W. H.; Nardi, V.

    1985-08-01

    Recent measurements of the energy spectrum of the plasma-focus-generated deuteron beam yield as spectrum of the form N(E)=(approx.) E to the -2.7 for 1MeV E 13 MeV. Other measurements show that the beta 1 electron beam which is generated simultaneously with the deuteron beam is interrupted into segments of spacing 25ps and duration approximately 4ps. A stuttering-electro-magnetic-ram (ser) model of the plasma focus in proposed which is similar to Raudorf's electronic ram which produces a similar spectrum for an electron beam for 1Mev E 10MeV. It is proposed that the cosmic ray spectrum and the giganic galactic jets are both generated by ser action near the centers of active galaxies.

  4. The electromagnetic ram action of the plasma focus as a paradigm for the generation of cosmic rays and the gigantic jets in active galaxies

    NASA Technical Reports Server (NTRS)

    Bostick, W. H.; Nardi, V.

    1985-01-01

    Recent measurements of the energy spectrum of the plasma-focus-generated deuteron beam yield as spectrum of the form N(E)=(approx.) E to the -2.7 for 1MeV E 13 MeV. Other measurements show that the beta 1 electron beam which is generated simultaneously with the deuteron beam is interrupted into segments of spacing 25ps and duration approximately 4ps. A stuttering-electro-magnetic-ram (ser) model of the plasma focus in proposed which is similar to Raudorf's electronic ram which produces a similar spectrum for an electron beam for 1Mev E 10MeV. It is proposed that the cosmic ray spectrum and the giganic galactic jets are both generated by ser action near the centers of active galaxies.

  5. Synergistic combination of multi-Zr(IV) cations and lacunary Keggin germanotungstates leading to a gigantic Zr24-cluster-substituted polyoxometalate.

    PubMed

    Huang, Ling; Wang, Sa-Sa; Zhao, Jun-Wei; Cheng, Lin; Yang, Guo-Yu

    2014-05-28

    Synergistic directing roles of six lacunary fragments resulted in an unprecedented Zr24-cluster substituted poly(polyoxotungstate) Na10K22[Zr24O22(OH)10(H2O)2(W2O10H)2(GeW9O34)4(GeW8O31)2]·85H2O (Na10K22·1·85H2O), which contains the largest [Zr24O22(OH)10(H2O)2] (Zr24) cluster in all the Zr-based poly(polyoxometalate)s to date. The most remarkable feature is that the centrosymmetric Zr24-cluster-based hexamer contains two symmetry-related [Zr12O11(OH)5(H2O)(W2O10H)(GeW9O34)2(GeW8O31)](16-) trimers via six μ3-oxo bridges and was simultaneously trapped by three types of different segments of B-α-GeW9O34, B-α-GeW8O31, and W2O10. The other interesting characteristic is that there are two pairs of intriguing triangular atom alignments: one is composed of the Zr(2,4,6,8,11) and W21 atoms and the other contains the Ge(1-3), Zr(3,5,7,9,10,12) and W26 atoms, and the Zr5 atom is inside the triangle; a linking mode is unobserved. The oxygenation reactions of thioethers by H2O2 were evaluated when Na10K22·1·85H2O served as a catalyst. Results show that it is an effective catalyst for oxygenation of thioethers by H2O2. The unique redox property of oxygen-enriched polyoxotungstate fragments and Lewis acidity of the Zr cluster imbedded in Na10K22·1·85H2O provide a sufficient driving force for the catalytic conversion from thioethers to sulfoxides/sulfones. PMID:24819708

  6. McCune-Albright syndrome

    MedlinePlus

    ... bones in the face Gigantism Irregular, large patchy cafe-au-lait spots , especially on the back ... Acromegaly Adrenal abnormalities Gigantism Hyperparathyroidism Hyperthyroidism Hypophosphatemia Large cafe-au-lait spots on the skin Liver disease, ...

  7. Fermi discovers giant bubbles in Milky Way

    NASA Video Gallery

    Using data from NASA's Fermi Gamma-ray Space Telescope, scientists have recently discovered a gigantic, mysterious structure in our galaxy. This feature looks like a pair of bubbles extending above...

  8. Pituitary tumor

    MedlinePlus

    ... or more of the following conditions can occur: Hyperthyroidism (thyroid gland makes too much of its hormones; ... syndrome Cyst Endocrine glands Gigantism Growth hormone test Hyperthyroidism Hypopituitarism Multiple endocrine neoplasia (MEN) I Prolactin blood ...

  9. The evolution of high energy accelerators

    SciTech Connect

    Courant, E.D.

    1989-10-01

    In this lecture I would like to trace how high energy particle accelerators have grown from tools used for esoteric small-scale experiments to gigantic projects being hotly debated in Congress as well as in the scientific community.

  10. [Acromegaly--from myths to facts].

    PubMed

    Kałuzny, Marcin; Bolanowski, Marek

    2008-01-01

    The authors present numerous historical descriptions of persons who might suffered from gigantism or acromegaly. The oldest medical data of patients, initial attempts of causal neurosurgical treatment, history of growth hormone, insulin-like growth factor-1, growth hormone releasing hormone and somatostatin discovery is reported. The highest contemporary living persons are also listed. PMID:18615400

  11. Rock "n" Roll Presidents on Mount Rushmore. Second Grade Activity. Schools of California Online Resources for Education (SCORE): Connecting California's Classrooms to the World.

    ERIC Educational Resources Information Center

    Sawyer, Debbie

    A historian, Doane Robinson, and a sculptor, Gutzon Borglum, worked together to build a gigantic monument in South Dakota that honored four of the greatest U.S. presidents: George Washington, Abraham Lincoln, Theodore Roosevelt, and Thomas Jefferson. Robinson and Borglum wanted the monument to represent U.S. ideals. To celebrate the anniversary of…

  12. Riding the Dinosaur Wave.

    ERIC Educational Resources Information Center

    Girod, Mark

    1998-01-01

    As his geology students' specialized knowledge of the Mesozoic era increased, a high school teacher realized he needed a way to showcase their work. The Mesozoic Resource Center's biggest hit was a walk-through diorama showing how life might have been during each of three Mesozoic periods. Highlights included two gigantic student-built dinosaur…

  13. Mathematics in Use: Suspension Bridges.

    ERIC Educational Resources Information Center

    Ginther, John L.

    1992-01-01

    Reviews the mathematics utilized in the design and construction of suspension bridges, in general, then illustrates these mathematical concepts by examining data associated with the Mackinac Bridge, which connects the two peninsulas of Michigan. Emphasizes the strong interest factor these gigantic structures have for students by attaching a sense…

  14. Not Your Parents' Marching Bands: The History of HONK!, Pedagogy and Music Education

    ERIC Educational Resources Information Center

    Garofalo, Reebee

    2011-01-01

    The HONK! Festival of Activist Street Bands (honkfest.org) is an independent, grassroots, non-commercial weekend festival held each autumn in Somerville, Massachusetts. It is a moving spectacle of colourful marching bands, gigantic puppets, creative bikers, jugglers, hoopers, flag twirlers and stilt walkers, interspersed with unions, activist…

  15. Molecular Clouds, Star Formation and Galactic Structure.

    ERIC Educational Resources Information Center

    Scoville, Nick; Young, Judith S.

    1984-01-01

    Radio observations show that the gigantic clouds of molecules where stars are born are distributed in various ways in spiral galaxies, perhaps accounting for the variation in their optical appearance. Research studies and findings in this area are reported and discussed. (JN)

  16. Shake It up

    ERIC Educational Resources Information Center

    Gilstrap, Tatiana; Sheldon, Peter; Schimmoeller, Peggy

    2010-01-01

    If scientists know where earthquakes are most likely to occur, then architects and engineers can design safer buildings for such areas and potentially prevent some of the devastating aftereffects. Engineers have met this challenge through the design and use of gigantic shake tables to evaluate the stability of various structures. In this 45-minute…

  17. Oxygen from the lunar soil by molten silicate electrolysis

    NASA Technical Reports Server (NTRS)

    Colson, Russell O.; Haskin, Larry A.

    1992-01-01

    Accepting that oxygen, rather than gigantic gems or gold, is likely to make the Moon's Klondike, the extraction of oxygen from the lunar soil by molten silicate electrolysis has chosen to be investigated. Process theory and proposed lunar factory are addressed.

  18. Kuba, Kids, and an Airport: How One Community Celebrates Art and Imagination.

    ERIC Educational Resources Information Center

    Eller, Lennee; Grigsby, Eugene, Jr.

    2003-01-01

    Describes "The Kuba Project: An Exhibit of Gigantic Proportions" in which high school students learned about the Kuba people of the Congo and created monumental ceramic works of art. Explains that the student artwork was exhibited at the Phoenix Sky Harbor International Airport in Phoenix (Arizona) as part of the Sky Harbor Art Program. (CMK)

  19. The Story of Semco: The Company that Humanized Work

    ERIC Educational Resources Information Center

    Vanderburg, David

    2004-01-01

    This article examines and analyzes Semco, a company that changed the way it viewed and treated its workers for the better. It is the contention of Semco's CEO, that at most large corporations "everyone is part of a gigantic, impersonal machine, and it is impossible to feel motivated when you feel you are just another cog. Human nature demands…

  20. Gender, Education and Child Labour: A Sociological Perspective

    ERIC Educational Resources Information Center

    Bhat, Bilal Ahmad

    2010-01-01

    In all societies, boys and girls are assigned different societal roles and experience different perspectives of life as a result of their being male or female. Such differences have a gigantic impact on their lives. The importance of gender perspective is very important in understanding the convolution of child labour. Gender, as opposed to sex,…

  1. Variations on a Theme: Fourth Annual Review, 1969-70.

    ERIC Educational Resources Information Center

    Committee of Presidents of Universities of Ontario, Toronto.

    Over the past several years the universities of Ontario have made a gigantic effort under the direction of the Committee of Presidents of Universities of Ontario to provide quality higher education for all qualified students. Inter institutional cooperation and coordination has been a must in this effort, and maximum utilization of available…

  2. The Experience of External Studies. Occasional Papers No. 4.

    ERIC Educational Resources Information Center

    Riverina Coll. of Advanced Education, Wagga Wagga, New South Wales (Australia).

    This document brings together four invited papers by external students who have graduated from Riverina College: (1) "The External Student: One Profile" (Christine Del Gigante); (2) "Managing Life as a External Student" (Robert Landow); (3) "The Computerised Student" (John Chant); and (4) "The Right to Study" (Coral Davidson). Topics covered…

  3. Coral Reefs: A Gallery Program, Grades 7-12.

    ERIC Educational Resources Information Center

    National Aquarium in Baltimore, MD. Dept. of Education.

    Gallery classes at the National Aquarium in Baltimore give the opportunity to study specific aquarium exhibits which demonstrate entire natural habitats. The coral reef gallery class features the gigantic western Atlantic coral reef (325,000 gallons) with over 1,000 fish. The exhibit simulates a typical Caribbean coral reef and nearby sandy…

  4. Malformaciones arteriovenosas revisión y análisis descriptivo de 52 mavs tratadas durante el periodo de 2000-2010

    PubMed Central

    Rinaldi, Mariano; Mezzano, Emilio; Berra, Matias S.; Parés, Herald R.; Olocco, Ricardo V.; Papalini, Francisco R.

    2015-01-01

    Objetivo: Describir nuestra experiencia en el manejo de las Mavs analizando las características clínicas de los pacientes y los resultados postoperatorios. Método de análisis: Realizamos un análisis retrospectivo de 52 pacientes admitidos en el Servicio de neurocirugía para manejo quirúrgico: La información de referencia incluyo síntomas al inicio, diagnostico de admisión, hallazgos neurológicos y hallazgos en estudio por imágenes tales como tomografía cerebral, IRM cerebral y angiografía por sustracción digital. Los hallazgos postoperatorios de interés fueron: Mortalidad, examen neurológico postoperatorio y complicaciones asociadas. Presentamos nuestro análisis estadístico. Resultados: Edad promedio: 37,7 años. Distribución: Hombres: 61,5%. Motivos de consulta más frecuentes: Cefalea 63,5%, evento hemorrágico 59,6%, convulsiones 26,9%. Localización: Supratentorial: 92,9%, Infratentorial: 7,2%. 30,8%, de las Mavs fueron grado 2 y grado 3 Cincuenta por ciento del total presentaron aneurismas, del total de la MAVs, 59,6% debutó con sangrado, 26,9% con Crisis Convulsivas y 13,5% con déficit neurológico. Recibieron tratamiento endovascular previo a cirugía 30,7%. Durante el postoperatorio 23,1% presentaron mejoría clínica, 57,7% no presento modificación, 19,2% empeoraron en el postoperatorio. La mortalidad fue 13,5%. Conclusión: Creemos que el subgrupo de Mavs grados III a V representan una entidad que requiere una compleja toma de decisiones dada la alta incidencia de aneurismas asociados que presentan y su asociación con eventos de sangrado. Nuestra mortalidad postoperatoria coincide con la bibliografía. Palabras clave, Mavs- aneurismas asociados- Acv hemorrágico- convulsiones. PMID:26600984

  5. [In Process Citation].

    PubMed

    Daponte Codina, A; Bolivar Muñoz, J; Sánchez-Cantalejo, E; Mateo-Rodríguez, I; Babio, G; Romo-Avilés, N; Rosell-Ortiz, F; Grupo de Estudio de Género Y Enfermedades Cardiovasculares, G

    2016-01-01

     RESUMEN              Fundamento. Identificar factores asociados a la demora prehospitalaria en personas que han tenido un síndrome coronario agudo             Método. Se estudiaron mediante encuesta pacientes ingresados por síndrome coronario agudo en los 33 hospitales públicos andaluces, obteniéndose información sobre diferentes tipos de variables: socio-demográficas, contextuales, clínicas, percepción, actuaciones, y transporte. Se aplicaron modelos de regresión logística multivariante para calcular las odds ratio para la demora.             Resultados. De los 1.416 pacientes en total, más de la mitad tuvieron una demora superior a la hora. Se asocia a la distancia al hospital y al medio de transporte: cuando el evento ocurre en la misma ciudad del hospital, utilizar medios propios aumenta la demora, odds ratio= 1,51 (1,02-2,23);  si la distancia es entre 1-25 kilómetros, no hay una diferencia entre medios propios y ambulancia, odds ratio = 1,41 y odds ratio = 1,43 respectivamente; y cuando supera los25 kilómetros la ambulancia implica mayor demora, odds ratio = 3,13 y odds ratio = 2,20 respectivamente. Además, la sintomatología típica reduce la demora entre los hombres, pero la aumenta entre las mujeres. Asimismo, no darle importancia, esperar a la resolución de los síntomas, buscar atención sanitaria diferente a urgencias hospitalarias o al 061, tener antecedentes, encontrarse fuera de la vivienda habitual, y tener ingresos menores de 1.500 euros aumentan la demora. Tener síntomas respiratorios la reduce.             Conclusiones. La demora prehospitalaria no se ajusta a las recomendaciones sanitarias, asociándose al  entorno físico y social, a factores clínicos, y de percepción y actitudinales de los sujetos.              Palabras clave. Síndrome coronario agudo. Demora prehospitalaria. Género. Servicios de emergencias sanitarias. Desigualdades. PMID:27125609

  6. A giant phyllodes tumor causing ulceration and severe breast disfigurement: case report and review of giant phyllodes

    PubMed Central

    Sbeih, Mohammed A.; Engdahl, Ryan; Landa, Marina; Ojutiku, Oreoluwa; Morrison, Norman; Depaz, Hector

    2015-01-01

    Phyllodes tumors are rare fibroepithelial tumors that account for <1% of the breast tumors in women. These tumors are often benign unilateral lesions of the female breast (70%). Less common are malignant phyllodes, which have the potential for hematogenous spread. Phyllodes tumors can be seen in all age groups, and the median age of presentation is 45 years. Surgery is the main form of treatment. Wide excisions with margins of 1cm are suggested. While smaller and moderate size phyllodes may typically be seen, gigantic ones are very rare. These may be seen in neglected tumors. By definition, a giant phyllodes tumor is one larger than 10 cm in diameter. We report a gigantic phyllodes tumor that grew over 7 years period causing significant ulceration and disfigurement and review features of these tumors and management. PMID:26703928

  7. A giant phyllodes tumor causing ulceration and severe breast disfigurement: case report and review of giant phyllodes.

    PubMed

    Sbeih, Mohammed A; Engdahl, Ryan; Landa, Marina; Ojutiku, Oreoluwa; Morrison, Norman; Depaz, Hector

    2015-01-01

    Phyllodes tumors are rare fibroepithelial tumors that account for <1% of the breast tumors in women. These tumors are often benign unilateral lesions of the female breast (70%). Less common are malignant phyllodes, which have the potential for hematogenous spread. Phyllodes tumors can be seen in all age groups, and the median age of presentation is 45 years. Surgery is the main form of treatment. Wide excisions with margins of 1cm are suggested. While smaller and moderate size phyllodes may typically be seen, gigantic ones are very rare. These may be seen in neglected tumors. By definition, a giant phyllodes tumor is one larger than 10 cm in diameter. We report a gigantic phyllodes tumor that grew over 7 years period causing significant ulceration and disfigurement and review features of these tumors and management. PMID:26703928

  8. Latent outflow activity for western Tharsis, Mars: Significant flood record exposed

    USGS Publications Warehouse

    Dohm, J.M.; Anderson, R.C.; Baker, V.R.; Ferris, J.C.; Rudd, L.P.; Hare, T.M.; Rice, J. W., Jr.; Casavant, R.R.; Strom, R.G.; Zimbelman, J.R.; Scott, D.H.

    2001-01-01

    Observations permitted by the newly acquired Mars Observer Laser Altimeter data have revealed a system of gigantic valleys northwest of the huge Martian shield volcano, Arsia Mons, in the western hemisphere of Mars (northwestern slope valleys (NSVs)). These features, which generally correspond spatially to gravity lows, are obscured by veneers of materials including volcanic lava flows, air fall deposits, and eolian materials. Geologic investigations of the Tharsis region suggest that the system of gigantic valleys predates the construction of Arsia Mons and its extensive associated lava flows of mainly late Hesperian and Amazonian age and coincides stratigraphically with the early development of the outflow channels that debouch into Chryse Planitia. Similar to the previously identified outflow channels, which issued tremendous volumes of water into topographic lows such as Chryse Planitia, the NSVs potentially represent flooding of immense magnitude and, as such, a source of water for a northern plains ocean.

  9. High-altitude electrical discharges associated with thunderstorms and lightning

    NASA Astrophysics Data System (ADS)

    Liu, Ningyu; McHarg, Matthew G.; Stenbaek-Nielsen, Hans C.

    2015-12-01

    The purpose of this paper is to introduce electrical discharge phenomena known as transient luminous events above thunderstorms to the lightning protection community. Transient luminous events include the upward electrical discharges from thunderstorms known as starters, jets, and gigantic jets, and electrical discharges initiated in the lower ionosphere such as sprites, halos, and elves. We give an overview of these phenomena with a focus on starters, jets, gigantic jets, and sprites, because similar to ordinary lightning, streamers and leaders are basic components of these four types of transient luminous events. We present a few recent observations to illustrate their main properties and briefly review the theories. The research in transient luminous events has not only advanced our understanding of the effects of thunderstorms and lightning in the middle and upper atmosphere, but also improved our knowledge of basic electrical discharge processes critical for sparks and lightning.

  10. Crystallographic Observation of Dynamic Gas Adsorption Sites and Thermal Expansion in a Breathable Fluorous Metal?Organic Framework

    SciTech Connect

    Yang, Chi; Wang, Xiaoping; Omary, Mohammad A

    2009-01-01

    Playing accordion: Cooling a single crystal of a microporous fluorous metal-organic framework under ambient atmosphere leads to very large breathing upon gas adsorption, during which multiple N2 molecules are filled into channels and cages (see picture). While the framework exhibits remarkable positive thermal expansion under vacuum, a gigantic apparent negative thermal expansion takes place when the crystal is exposed to N2 at ambient pressure.

  11. Treatment of macroglossia in Beckwith-Wiedemann syndrome.

    PubMed

    Clauser, Luigi; Tieghi, Riccardo; Polito, Jessica

    2006-03-01

    A case of macroglossia caused by Beckwith Wiedemann syndrome is reported. Beckwith-Wiedemann Syndrome is an overgrowth disorder characterized by a constellation of congenital anomalies. The most common manifestations are omphalocele, macroglossia, gigantism, and visceromegaly. When the tongue reaches a huge dimension, clinical symptoms are represented by dysphagia, alterations in speech, difficulty in chewing, obstruction of the upper airways, and psychologic consequences derived from the patient's physical appearance. The authors describe the surgical strategy performed in the reported case. PMID:16633192

  12. Four New Bat Species (Rhinolophus hildebrandtii Complex) Reflect Plio-Pleistocene Divergence of Dwarfs and Giants across an Afromontane Archipelago

    PubMed Central

    Taylor, Peter J.; Stoffberg, Samantha; Monadjem, Ara; Schoeman, Martinus Corrie; Bayliss, Julian; Cotterill, Fenton P. D.

    2012-01-01

    Gigantism and dwarfism evolve in vertebrates restricted to islands. We describe four new species in the Rhinolophus hildebrandtii species-complex of horseshoe bats, whose evolution has entailed adaptive shifts in body size. We postulate that vicissitudes of palaeoenvironments resulted in gigantism and dwarfism in habitat islands fragmented across eastern and southern Africa. Mitochondrial and nuclear DNA sequences recovered two clades of R. hildebrandtii senso lato which are paraphyletic with respect to a third lineage (R. eloquens). Lineages differ by 7.7 to 9.0% in cytochrome b sequences. Clade 1 includes R. hildebrandtii sensu stricto from the east African highlands and three additional vicariants that speciated across an Afromontane archipelago through the Plio-Pleistocene, extending from the Kenyan Highlands through the Eastern Arc, northern Mozambique and the Zambezi Escarpment to the eastern Great Escarpment of South Africa. Clade 2 comprises one species confined to lowland savanna habitats (Mozambique and Zimbabwe). A third clade comprises R. eloquens from East Africa. Speciation within Clade 1 is associated with fixed differences in echolocation call frequency, and cranial shape and size in populations isolated since the late Pliocene (ca 3.74 Mya). Relative to the intermediate-sized savanna population (Clade 2), these island-populations within Clade 1 are characterised by either gigantism (South African eastern Great Escarpment and Mts Mabu and Inago in Mozambique) or dwarfism (Lutope-Ngolangola Gorge, Zimbabwe and Soutpansberg Mountains, South Africa). Sympatry between divergent clades (Clade 1 and Clade 2) at Lutope-Ngolangola Gorge (NW Zimbabwe) is attributed to recent range expansions. We propose an “Allometric Speciation Hypothesis”, which attributes the evolution of this species complex of bats to divergence in constant frequency (CF) sonar calls. The origin of species-specific peak frequencies (overall range = 32 to 46 kHz) represents the

  13. Titin: central player of hypertrophic signaling and sarcomeric protein quality control.

    PubMed

    Kötter, Sebastian; Andresen, Christian; Krüger, Martina

    2014-11-01

    The giant sarcomeric protein titin has multiple important functions in striated muscle cells. Due to its gigantic size, its central position in the sarcomere and its elastic I-band domains, titin is a scaffold protein that is important for sarcomere assembly, and serves as a molecular spring that defines myofilament distensibility. This review focuses on the emerging role of titin in mechanosensing and hypertrophic signaling, and further highlights recent evidence that links titin to sarcomeric protein turnover. PMID:25205716

  14. The Oort cloud

    NASA Technical Reports Server (NTRS)

    Marochnik, Leonid S.; Mukhin, Lev M.; Sagdeev, Roald Z.

    1991-01-01

    Views of the large-scale structure of the solar system, consisting of the Sun, the nine planets and their satellites, changed when Oort demonstrated that a gigantic cloud of comets (the Oort cloud) is located on the periphery of the solar system. The following subject areas are covered: (1) the Oort cloud's mass; (2) Hill's cloud mass; (3) angular momentum distribution in the solar system; and (4) the cometary cloud around other stars.

  15. Oral polyp as the presenting feature of Beckwith-Wiedemann syndrome in a child.

    PubMed

    Kujan, Omar; Raheel, Syed Ahmed; King, David; Iqbal, Fareed

    2015-01-01

    Beckwith-Wiedemann syndrome (BWS) is a congenital growth disorder characterised by abdominal wall defects, macroglossia and somatic gigantism. A number of associated features, including gastrointestinal and urinary tract polyps, have been described, but there are no previous reports of oral polyps occurring in this syndrome. We describe the first case of BWS presenting with an oral polyp. Clinicians should be alert to the possibility of BWS if other features of the syndrome are present, in children with oral polyps. PMID:26323977

  16. Discos de acreción circumplanares: Modelo de Co-acreción

    NASA Astrophysics Data System (ADS)

    Parisi, M. G.; de Elía, G.

    Los discos de acreción circumplanetarios precursores de los satélites regulares de los planetas gigantes, se pueden formar por cuatro mecanismos (Pollack y otros, 1991, In Uranus, Bergtralh, Miner y Mattews, Eds., p. 469, Univ. de Arizona Press, Tucson). En este trabajo estudiamos uno de tales mecanismos: el Modelo de Co-acreción. En dicho modelo, el disco circumplanetario se forma a partir de las colisiones mutuas entre planetesimales dentro de la esfera de Hill del planeta durante el proceso de formación planetaria. Realizamos un modelo semi-analítico para calcular la masa del disco y compararla con la masa requerida para formar los satélites regulares de los planetas gigantes. Hemos obtenido una cota superior para la masa del disco que resulta inferior a la masa de los satélites más grandes de los planetas gigantes. En principio, estos resultados permitirían descartar el modelo de co-acreción como uno de los procesos que podrían dar lugar a la formación de los satélites regulares. Estos resultados permiten obtener restricciones en el escenario de formación planetaria y en los mecanismos de formación de sistemas de satélites.

  17. Somatic mosaicism underlies X-linked acrogigantism syndrome in sporadic male subjects.

    PubMed

    Daly, Adrian F; Yuan, Bo; Fina, Frederic; Caberg, Jean-Hubert; Trivellin, Giampaolo; Rostomyan, Liliya; de Herder, Wouter W; Naves, Luciana A; Metzger, Daniel; Cuny, Thomas; Rabl, Wolfgang; Shah, Nalini; Jaffrain-Rea, Marie-Lise; Zatelli, Maria Chiara; Faucz, Fabio R; Castermans, Emilie; Nanni-Metellus, Isabelle; Lodish, Maya; Muhammad, Ammar; Palmeira, Leonor; Potorac, Iulia; Mantovani, Giovanna; Neggers, Sebastian J; Klein, Marc; Barlier, Anne; Liu, Pengfei; Ouafik, L'Houcine; Bours, Vincent; Lupski, James R; Stratakis, Constantine A; Beckers, Albert

    2016-04-01

    Somatic mosaicism has been implicated as a causative mechanism in a number of genetic and genomic disorders. X-linked acrogigantism (XLAG) syndrome is a recently characterized genomic form of pediatric gigantism due to aggressive pituitary tumors that is caused by submicroscopic chromosome Xq26.3 duplications that includeGPR101 We studied XLAG syndrome patients (n= 18) to determine if somatic mosaicism contributed to the genomic pathophysiology. Eighteen subjects with XLAG syndrome caused by Xq26.3 duplications were identified using high-definition array comparative genomic hybridization (HD-aCGH). We noted that males with XLAG had a decreased log2ratio (LR) compared with expected values, suggesting potential mosaicism, whereas females showed no such decrease. Compared with familial male XLAG cases, sporadic males had more marked evidence for mosaicism, with levels of Xq26.3 duplication between 16.1 and 53.8%. These characteristics were replicated using a novel, personalized breakpoint junction-specific quantification droplet digital polymerase chain reaction (ddPCR) technique. Using a separate ddPCR technique, we studied the feasibility of identifying XLAG syndrome cases in a distinct patient population of 64 unrelated subjects with acromegaly/gigantism, and identified one female gigantism patient who had had increased copy number variation (CNV) threshold forGPR101that was subsequently diagnosed as having XLAG syndrome on HD-aCGH. Employing a combination of HD-aCGH and novel ddPCR approaches, we have demonstrated, for the first time, that XLAG syndrome can be caused by variable degrees of somatic mosaicism for duplications at chromosome Xq26.3. Somatic mosaicism was shown to occur in sporadic males but not in females with XLAG syndrome, although the clinical characteristics of the disease were similarly severe in both sexes. PMID:26935837

  18. A unified model with a generalized gauge symmetry and its cosmological implications

    NASA Astrophysics Data System (ADS)

    Hsu, Jong-Ping; Cottrell, Kazuo O.

    2015-10-01

    A unified model is based on a generalized gauge symmetry with groups [SU3c]color×(SU2×U1)× [U1b×U1l]. It implies that all interactions should preserve conservation laws of baryon number, lepton number, and electric charge, etc. The baryonic U1b, leptonic U1l and color SU3c gauge transformations are generalized to involve nonintegrable phase factors. One has gauge invariant fourth-order equations for massless gauge fields, which leads to linear potentials in the [U1b×U1l] and color [SU3c] sectors. We discuss possible cosmological implications of the new baryonic gauge field. It can produce a very small constant repulsive force between two baryon galaxies (or between two anti-baryon galaxies), where the baryon force can overcome the gravitational force at very large distances and leads to an accelerated cosmic expansion. Based on conservation laws in the unified model, we discuss a simple rotating dumbbell universe with equal amounts of matter and anti-matter, which may be pictured as two gigantic rotating clusters of galaxies. Within the gigantic baryonic cluster, a galaxy will have an approximately linearly accelerated expansion due to the effective force of constant density of all baryonic matter. The same expansion happens in the gigantic anti-baryonic cluster. Physical implications of the generalized gauge symmetry on charmonium confining potentials due to new SU3c field equations, frequency shift of distant supernovae Ia and their experimental tests are discussed.

  19. X-linked Acrogigantism (X-LAG) Syndrome: Clinical Profile and Therapeutic Responses

    PubMed Central

    Beckers, Albert; Lodish, Maya Beth; Trivellin, Giampaolo; Rostomyan, Liliya; Lee, Misu; Faucz, Fabio R; Yuan, Bo; Choong, Catherine S; Caberg, Jean-Hubert; Verrua, Elisa; Naves, Luciana Ansaneli; Cheetham, Tim D; Young, Jacques; Lysy, Philippe A; Petrossians, Patrick; Cotterill, Andrew; Shah, Nalini Samir; Metzger, Daniel; Castermans, Emilie; Ambrosio, Maria Rosaria; Villa, Chiara; Strebkova, Natalia; Mazerkina, Nadia; Gaillard, Stéphan; Barra, Gustavo Barcelos; Casulari, Luis Augusto; Neggers, Sebastian J.; Salvatori, Roberto; Jaffrain-Rea, Marie-Lise; Zacharin, Margaret; Santamaria, Beatriz Lecumberri; Zacharieva, Sabina; Lim, Ee Mun; Mantovani, Giovanna; Zatelli, Maria Chaira; Collins, Michael T; Bonneville, Jean-François; Quezado, Martha; Chittiboina, Prashant; Oldfield, Edward H.; Bours, Vincent; Liu, Pengfei; De Herder, Wouter; Pellegata, Natalia; Lupski, James R.; Daly, Adrian F.; Stratakis, Constantine A.

    2015-01-01

    X-linked acro-gigantism (X-LAG) is a new syndrome of pituitary gigantism, caused by microduplications on chromosome Xq26.3, encompassing the gene GPR101, which is highly upregulated in pituitary tumors. We conducted this study to explore the clinical, radiological and hormonal phenotype and responses to therapy in patients with X-LAG syndrome. The study included 18 patients (13 sporadic) with X-LAG and a microduplication in chromosome Xq26.3. All sporadic cases had unique duplications and the inheritance pattern in 2 families was dominant with all Xq26.3 duplication carriers being affected. Patients began to grow rapidly as early as 2–3 months of age (median 12 months). At diagnosis (median delay 27 months), patients had a median height and weight SDS score of >+3.9 SDS. Apart from the increased overall body size, the children had acromegalic symptoms including acral enlargement and facial coarsening. More than a third of cases had increased appetite. Patients had marked hypersecretion of GH/IGF-1 and prolactin, usually due to a pituitary macroadenoma or hyperplasia. Primary neurosurgical control was achieved with extensive anterior pituitary resection but postoperative hypopituitarism was frequent. Control with somatostatin analogs was not readily achieved despite moderate to high somatostatin receptor subtype-2 expression in tumor tissue. Postoperative adjuvant pegvisomant achieved control of IGF-1 all 5 cases in which it was employed. X-LAG is a new infant-onset gigantism syndrome that has a severe clinical phenotype leading to challenging disease management. PMID:25712922

  20. Teratological Nymphal Ixodes scapularis (Acari: Ixodidae) From Wisconsin.

    PubMed

    Larson, Scott R; Paskewitz, Susan M

    2016-03-01

    Abnormalities of physiological development (teratological forms) in ticks are rare. The occurrence of gigantism, dwarfism, gynandromorphs, missing legs, extra legs, and asymmetries is most often reported from lab-reared specimens, but has been observed in field-collected specimens. All morphologically anomalous ticks (besides gynandromorphy) described to date are from species other than Ixodes scapularis Say (Acari: Ixodidae). Here we describe four teratological I. scapularis nymphs collected while dragging vegetation in Wisconsin in 2015, including two asymmetrical ticks, one with a missing leg, and one with an extra leg. PMID:26681790

  1. Vignettes from the history of overgrowth and related syndromes.

    PubMed

    Beckwith, J B

    1998-10-01

    Vignettes of several stages in the evolution of present concepts of overgrowth and related syndromes are presented. The scientific study of this topic did not begin until the 18th century because of its delayed emergence from superstition and fallacy. Examples of early superstitions concerning gigantism are presented, with some historical comments on infant giants. The pioneering contributions of Isodore Geoffroy Saint-Hilaire to the scientific analysis of overgrowth are emphasized. Details concerning the early history of the growth syndrome associated with the names of Wiedemann and Beckwith is presented, with emphasis on cases reported prior to ours. PMID:9781902

  2. Large space structures - Fantasies and facts

    NASA Technical Reports Server (NTRS)

    Card, M. F.; Boyer, W. J.

    1980-01-01

    A review of large space structures activities from 1973 to 1979 is presented. Long-range studies of space colonies, gigantic solar power stations and projected earth applications revived interest in space activities. Studies suggest opportunities for advanced antenna and platform applications. Matching low-thrust propulsion to large flexible vehicles will be a key technology. Current structures technology investigations include deployable and erectable structures and assembly techniques. Based on orbited structures experience, deployment reliability is a critical issue for deployable structures. For erectable structures, concepts for earth-fabricated and space-fabricated memb

  3. Bursting money bins, the ice and water structure

    NASA Astrophysics Data System (ADS)

    Bagnoli, Franco

    2015-05-01

    In the classic comics by Carl Barks, "The Big Bin on Killmotor Hill" [1], Uncle Scrooge, trying to defend his money bin from the Beagle Boys, follows a suggestion by Donald Duck, and fills the bin with water. Unfortunately, that night is going be the coldest one in the history of Ducksburg. The water freezes, bursting the "ten-foot walls'' of the money bin, and finally the gigantic cube of ice and dollars slips down the hill up to the Beagle Boys lot.

  4. Generation-X Mission Technology Drivers

    NASA Technical Reports Server (NTRS)

    Zhang, Will

    2004-01-01

    Gen-X is envisioned to be an observatory with a gigantic X-ray collection area and exquisite angular resolution and energy spectral resolution. As such it presents a number of technological challenges: extremely lightweight X-ray optics, large area and fast readout imaging detectors with excellent energy resolution, and efficient gratings. These challenges call for development of both the basic technologies and large-scale precision manufacture techniques. In this paper we present and discuss these challenges and outline a plan that will address these challenges in the next two decades.

  5. Characterization of fossil remains using XRF, XPS and XAFS spectroscopies

    NASA Astrophysics Data System (ADS)

    Zougrou, I. M.; Katsikini, M.; Pinakidou, F.; Brzhezinskaya, M.; Papadopoulou, L.; Vlachos, E.; Tsoukala, E.; Paloura, E. C.

    2016-05-01

    Synchrotron radiation micro-X-Ray Fluorescence (μ-XRF), X-ray photoelectron (XPS) and X-ray Absorption Fine Structure (XAFS) spectroscopies are applied for the study of paleontological findings. More specifically the costal plate of a gigantic terrestrial turtle Titanochelon bacharidisi and a fossilized coprolite of the cave spotted hyena Crocuta crocuta spelaea are studied. Ca L 2,3-edge NEXAFS and Ca 2p XPS are applied for the identification and quantification of apatite and Ca containing minerals. XRF mapping and XAFS are employed for the study of the spatial distribution and speciation of the minerals related to the deposition environment.

  6. Breast enlargement after two reduction mastoplasties: a case report.

    PubMed

    Mottura, A Aldo

    2007-01-01

    In 1989, a bilateral breast reduction was performed for a large-breasted woman. She returned 1 year later with bilateral breast enlargement as severe as in the original case. The operation was repeated but in a more aggressive way. She became pregnant 2 years later, and both her small breasts began to grow again until they became gigantic. Hormonal tests showed results within the standard limits, and no medical treatment was effective. After the delivery, her breasts reduced in size spontaneously. PMID:17700982

  7. Assembly of polymer-gold nanostructures with high reproducibility into a monolayer film SERS substrate with 5 nm gaps for pesticide trace detection.

    PubMed

    Zhou, Xia; Zhou, Fei; Liu, Honglin; Yang, Liangbao; Liu, Jinhuai

    2013-10-01

    A very simple and versatile polymer assembly approach was developed. We use methoxy-mercapto-poly(ethylene glycol) (mPEG-SH) to conjugate multiple Au shapes to form dense Au monolayer films (MLFs) with 5 nm gaps and generate gigantic enhancement. The results of the discrete dipole approximation (DDA) method to calculate the local electric field distribution of the nanoparticle dimer are in agreement with the experimental data of sensitivity of multiple Au MLFs. 3D Raman spectra, relative standard deviation (RSD) calculation and Raman mapping were used to study the high-reproducibility of the assembled substrate, which is sufficient for trace pesticide residue detection. PMID:23912071

  8. Toward chemistry-based design of the simplest metalloenzyme-like catalyst that works efficiently in water.

    PubMed

    Kitanosono, Taku; Kobayashi, Shū

    2015-01-01

    Enzymes exhibit overwhelmingly superior catalysis compared with artificial catalysts. Current strategies to rival enzymatic catalysis require unmodified or minimally modified structures of active sites, gigantic molecular weight, and sometimes the use of harsh conditions such as extremely low temperatures in organic solvents. Herein, we describe a design of small molecules that act as the simplest metalloenzyme-like catalysts that can function in water, without mimicking enzyme structures. These artificial catalysts efficiently promoted enantioselective direct-type aldol reactions using aqueous formaldehyde. The reactions followed Michaelis-Menten kinetics, and heat-resistant asymmetric environments were constructed in water. PMID:25349140

  9. Probing membrane potential with nonlinear optics.

    PubMed Central

    Bouevitch, O; Lewis, A; Pinevsky, I; Wuskell, J P; Loew, L M

    1993-01-01

    The nonlinear optical phenomenon of second harmonic generation is shown to have intrinsic sensitivity to the voltage across a biological membrane. Our results demonstrate that this second order nonlinear optical process can be used to monitor membrane voltage with excellent signal to noise and other crucial advantages. These advantages suggest extensive use of this novel approach as an important new tool in elucidating membrane potential changes in biological systems. For this first demonstration of the effect we use a chiral styryl dye which exhibits gigantic second harmonic signals. Possible mechanisms of the voltage dependence of the second harmonic signal are discussed. PMID:8218895

  10. Theory of magneto-optical effects in helical multiferroic materials via toroidal magnon excitation

    NASA Astrophysics Data System (ADS)

    Miyahara, S.; Furukawa, N.

    2014-05-01

    We investigate dynamical magnetoelectric effect owing to Nambu-Goldstone magnon resonance in helical multiferroic materials. Using the spin wave expansion, we analyzed magneto- and electroactive modes in the J1-J2 Heisenberg model through the spin-current mechanism. Under external magnetic field, the Nambu-Goldstone magnons accompany dynamical toroidal moments, i.e., toroidal magnons, and their resonant absorption shows anomalous features such as nonreciprocal directional dichroism and natural circular dichroism. The estimation indicates that such effects are gigantic in helical magnets.

  11. Design of a Template for Handwriting Based Hindi Text Entry in Handheld Devices

    NASA Astrophysics Data System (ADS)

    Gangopadhyay, Diya; Vasal, Ityam; Yammiyavar, Pradeep

    Mobile phones, in the recent times, have become affordable and accessible to a wider range of users including the hitherto technologically and economically under-represented segments. Indian users are a gigantic consumer base for mobile phones. With Hindi being one of the most widely spoken languages in the country and the primary tool of communication for about a third of its population, an effective solution for Hindi text entry in mobile devices is expected to be immensely useful to the non English speaking users. This paper proposes a mobile phone handwriting based text entry solution for Hindi language, which allows for an easy text entry method, while facilitating better recognition accuracy.

  12. Large meteorite impacts: The K/T model

    NASA Technical Reports Server (NTRS)

    Bohor, B. F.

    1992-01-01

    The Cretaceous/Tertiary (K/T) boundary event represents probably the largest meteorite impact known on Earth. It is the only impact event conclusively linked to a worldwide mass extinction, a reflection of its gigantic scale and global influence. Until recently, the impact crater was not definitively located and only the distal ejecta of this impact was available for study. However, detailed investigations of this ejecta's mineralogy, geochemistry, microstratigraphy, and textures have allowed its modes of ejection and dispersal to be modeled without benefit of a source crater of known size and location.

  13. Observation of three dimensional optical rogue waves through obstacles

    SciTech Connect

    Leonetti, Marco; Conti, Claudio

    2015-06-22

    We observe three-dimensional rogue waves in the speckle distribution of a spatially modulated optical beam. Light is transmitted beyond a partially reflecting obstacle generating optical rogue waves at a controlled position in the shadow of the barrier. When the barrier transmits only 0.07% of the input laser power, we observe the mostly localized event. These results demonstrate that an optimum amount of spatial non-homogeneity maximizes the probability of a gigantic event while the technique we exploit enables to control light behind a fully reflective wall.

  14. Ar-40 to Ar-39 dating of pseudotachylites from the Witwatersrand basin, South Africa, with implications for the formation of the Vredefort Dome

    NASA Technical Reports Server (NTRS)

    Trieloff, M.; Kunz, J.; Jessberger, E. K.; Reimold, W. U.; Boer, R. H.; Jackson, M. C.

    1992-01-01

    The formation of the Vredefort Dome, a structure in excess of 100 km in diameter and located in the approximate center of the Witwatersrand basin, is still the subject of lively geological controversy. It is widely accepted that its formation seems to have taken place in a single sudden event, herein referred to as the Vredefort event, accompanied by the release of gigantic amounts of energy. It is debated, however, whether this central event was an internal one, i.e., a cryptoexplosion triggered by volcanic or tectonic processes, or the impact of an extraterrestrial body. The results of this debate are presented.

  15. Slimeware: engineering devices with slime mold.

    PubMed

    Adamatzky, Andrew

    2013-01-01

    The plasmodium of the acellular slime mold Physarum polycephalum is a gigantic single cell visible to the unaided eye. The cell shows a rich spectrum of behavioral patterns in response to environmental conditions. In a series of simple experiments we demonstrate how to make computing, sensing, and actuating devices from the slime mold. We show how to program living slime mold machines by configurations of repelling and attracting gradients and demonstrate the workability of the living machines on tasks of computational geometry, logic, and arithmetic. PMID:23834592

  16. New possibilities for beam-beam and space-charge compensation: MCP gun and electron columns

    SciTech Connect

    Shiltsev, V.; /Fermilab

    2007-06-01

    We propose to use microchannel plate (MCP) as a gigantic quantum efficiency photo-cathode in electron guns. Another proposal is to use electron columns formed by ionization electrons in a longitudinal magnetic field for compensation of space charge effects in high intensity proton synchrotrons. Strong magnetic field is to assure that transverse distribution of electron space charge in the column is the same as in proton beam. Electrostatic electrodes are to control the accumulation and release of the electrons. Ions are not magnetized and drift away without affecting the compensation.

  17. Enhanced macroscopic quantum tunneling in Bi2Sr2CaCu2O8 + delta intrinsic Josephson-junction stacks.

    PubMed

    Jin, X Y; Lisenfeld, J; Koval, Y; Lukashenko, A; Ustinov, A V; Müller, P

    2006-05-01

    We have investigated macroscopic quantum tunneling in Bi(2)Sr(2)CaCu(2)O(8 + delta) intrinsic Josephson junctions at millikelvin temperatures using microwave irradiation. Measurements show that the escape rate for uniformly switching stacks of Nu junctions is about Nu(2) times higher than that of a single junction having the same plasma frequency. We argue that this gigantic enhancement of the macroscopic quantum tunneling rate in stacks is boosted by current fluctuations which occur in the series array of junctions loaded by the impedance of the environment. PMID:16712327

  18. [Rare clinical case of inflammatory macromastia in childhood].

    PubMed

    Alexandrova, E; Sergieva, S; Mihailova, I; Kostova, P

    2013-01-01

    AThe present and rare case is of a patient who developed macromastia in childhood. Usually, gigantomastia can occur as a complication due to pregnancy or it may occur in puberty, which is known as virginal breast hypertrophy, the second of which is more frequent. In our case, during the first decade of life, her breasts rapidly increased and reached gigantic sizes over a short period of time. The breasts were handing below the inguinal ligament and required a sling to support them. A phlegmon in the right axilla with a septic condition were the complications of this pathologic entity. The surgical intervention with postponed reconstruction was performed. PMID:24505630

  19. Microwave Magnetochiral Effect in Cu_{2}OSeO_{3}.

    PubMed

    Mochizuki, Masahito

    2015-05-15

    We theoretically find that in the multiferroic chiral magnet Cu_{2}OSeO_{3} resonant magnetic excitations are coupled to the collective oscillation of the electric polarization, and thereby attain simultaneous activity to the ac magnetic field and ac electric field. Because of the interference between these magnetic and electric activation processes, this material hosts a gigantic magnetochiral dichroism for microwaves, that is, a directional dichroism at gigahertz frequencies in the Faraday geometry. The absorption intensity of a microwave differs by as much as ~30% depending on whether its propagation direction is parallel or antiparallel to the external magnetic field. PMID:26024194

  20. Unified Picture for the Colossal Thermopower Compound FeSb2.

    PubMed

    Battiato, M; Tomczak, J M; Zhong, Z; Held, K

    2015-06-12

    We identify the driving mechanism of the gigantic Seebeck coefficient in FeSb2 as the phonon-drag effect associated with an in-gap density of states that we demonstrate to derive from excess iron. We accurately model electronic and thermoelectric transport coefficients and explain the so far ill-understood correlation of maxima and inflection points in different response functions. Our scenario has far-reaching consequences for attempts to harvest the spectacular power factor of FeSb2. PMID:26196816

  1. Controls on size and occurrence of the largest sub-aerial landslide on Earth: Seymareh (Saidmarreh) landslide, Zagros fold-thrust belt, Iran

    NASA Astrophysics Data System (ADS)

    Roberts, N. J.; Evans, S. G.

    2009-12-01

    Gigantic (> 1 Gm3) landslides are high-magnitude, low-frequency extremes of mass movements. They are important factors in topographic evolution and hazard in mountain regions due to their magnitude. However, few examples exist for study because of their infrequency. Consequently, controls on the location and size gigantic landslides remain poorly understood. Re-examination of the Seymareh (Saidmarreh) rock avalanche, Zagros fold-thrust belt, shows it to be the largest sub-aerial landslide on Earth (initial failure volume 38 Gm3), thus representing the upper magnitude limit for terrestrial landslides. Detailed examination of the source area (including orbital remote sensing, geotechnical investigation and structural mapping) provides new insights into controls on the size and mobility of gigantic landslides. The gigantic Early Holocene rockslide initiated on the northeast limb of Kabir Kuh, the largest anticline in the Zagros fold-thrust belt, and involved the simultaneous failure of a rock mass measuring 15 km along strike. The rockslide transformed into a rock avalanche that ran-out 19.0 km, filling two adjacent valleys and overtopping an intervening low mountain ridge. The failure involved 220 m of competent jointed limestone (Asmari Formation) underlain by 580 m of weaker mudrock-dominated units. Geologic structure, geomechanical strength and topography of the source slope strongly controlled failure initiation. Extreme landslide dimensions resulted in part from extensive uniform pre-failure stability, produced by structural and topographic features related to the large scale of the Kabir Kuh anticline. High continuity bedding planes determined the large lateral extent along strike. Bedding normal joints, the breached nature of the anticline and fluvial undercutting at the slope toe accommodated expansive lateral, headscarp and toe release, respectively, necessary for extensive failure. Geomechanically weak units at depth aided the penetration of the failure

  2. Sea, soil, sky: testing solar's limits

    SciTech Connect

    Hopkinson, J.; DeMeo, E.

    1981-12-01

    Gigantic heat exchangers for ocean-thermal energy conversion, vast plantations harvested for fuel, and massive arrays of photovoltaic cells in geocentric orbit have captured conceptual fancy in recent years. But the facts emerging from engineering assessments and the limitation of federal support point to lower priority among the research and development options. For the foreseeable future, greater emphasis will be placed on less grandiose schemes, such as forest and agricultural waste combustion and municipal refuse, which may have significant local impacts. 6 references, 1 figure.

  3. Combined Rastelli and Bentall Procedures for Pulmonary Atresia With Ventricular Septal Defect and a Large Aortopulmonary Collateral Artery and Ascending Aorta Aneurysm.

    PubMed

    Chiostri, Benjamin; Piccinini, Fernando; Vrancic, Mariano; Klinger, Daniel; Navia, Daniel; Lalor, Nicolas; Longo, Francisco; Kreutzer, Christián

    2014-06-23

    We report a challenging case of a 32-year-old patient in New York Heart Association (NYHA) class IV with pulmonary atresia, ventricular septal defect, a left aortopulmonary collateral artery, a right modified Blalock-Taussing shunt, and a gigantic aneurysm of the ascending aorta with severe aortic valve insufficiency. A combined Rastelli and Bentall procedure was performed by a joint adult and pediatric cardiovascular surgery team. One year after the operation, the patient is in NYHA class I, working full time. PMID:24958054

  4. Appoximation of individual cascades with energies above the GZK cut-off

    NASA Astrophysics Data System (ADS)

    Kirillov, A.; Kirillov, I.

    Approximation of individual cascades of gigantic energies is the essential part of prime particle energy determination methods. Fluctuation of cascades and their distribution shapes were investigated on the base of sufficient number of MK simulated showers, as dependent on prime energy, zenit angle and registration method. Individual cascades were approximated with high accuracy using some special parameters. It enables to create convenient formulae for approximation of individual cascades. Quality of this approximation and applicability of the traditional approximation of mean cascades for estimation of individual giganticcascades are discussed.

  5. The Final Proceedings of the DOE/NASA Solar Power Satellite Program Review

    NASA Technical Reports Server (NTRS)

    1980-01-01

    The solar power satellite (SPS) concept defined as 'placing gigantic satellites in geosynchronous orbit to capture sunlight, changing the energy into an appropriate form for transmission to Earth, and introducing the energy into the electric power grid' is evaluated in terms of costs and benefits. The concept development and evaluation program is reviewed in four general areas: systems definition; environmental; societal; and comparative assessments. Specific factors addressed include: transportation, construction in space, methods of conversion of sunlight into energy, transmission to Earth, maintenance in orbit and decommissioning of satellites; environmental, political, and economic effects; and comparison of SPS to other forms of power generation, both terrestrial and in space.

  6. Macrodystrophia Lipomatosa of the Toe: A Rare Case Report

    PubMed Central

    Durairaj, Alagar Raja

    2016-01-01

    Macrodystrophia lipomatosa is a rare congenital hamartoma presenting as a localized or generalized gigantism of a limb or digit manifesting from infancy to late adulthood. It is a progressive enlargement of the soft tissue components, especially fibrofatty tissue. The patient presents to us because of cosmetic reasons or mechanical issues secondary to degenerative joint disease, or features of neurovascular compression due to large osteophytes. Here, we present a case of this anomaly of the left second toe with complaints of difficulty in walking and wearing shoes, for which toe reduction surgery with partial amputation was done. PMID:27190893

  7. Upward electrical discharges observed above Tropical Depression Dorian

    PubMed Central

    Liu, Ningyu; Spiva, Nicholas; Dwyer, Joseph R.; Rassoul, Hamid K.; Free, Dwayne; Cummer, Steven A.

    2015-01-01

    Observation of upward electrical discharges from thunderstorms has been sporadically reported in the scientific literature. According to their terminal altitudes, they are classified as starters (20–30 km), jets (40–50 km) and gigantic jets (70–90 km). They not only have a significant impact on the occupied atmospheric volumes but also electrically couple different atmospheric regions. However, as they are rare and unpredictable, our knowledge of them has been built on observations that typically record only one type of such discharges. Here we report a close-distance observation of seven upward discharges including one starter, two jets and four gigantic jets above Tropical Depression Dorian. Our optical and electromagnetic data indicate that all events are of negative polarity, suggesting they are initiated in the same thundercloud charge region. The data also indicate that the lightning-like discharge channel can extend above thunderclouds by about 30 km, but the discharge does not emit low-frequency electromagnetic radiation as normal lightning. PMID:25607345

  8. Well-being and excellence in the Earth sciences

    NASA Astrophysics Data System (ADS)

    Drake, Charles L.

    In the symposium on Earth Sciences and Society at the Spring AGU Meeting May 29-June 1, Baltimore, Md.), I was assigned to speak on the maintenance of excellence and national well-being in the Earth sciences. I developed serious writer's block every time I approached the topic until I remembered a paragraph at the beginning of Doug Adams' great text, The Restaurant at the End of the Universe [Adams, 1982]. It tells how [A race of highly intelligent pan-dimensional beings once built themselves a gigantic supercomputer called Deep Thought to calculate once and for all the Answer to the Ultimate Question of Life, Universe and Everything. For seven and a half million years, Deep Thought computed and calculated, and in the end announced that the answer was in fact Forty-two—and so another, even bigger, computer had to be built to find out what the actual question was. And this computer, which was called the Earth, was so large that it was frequently mistaken for a planet-especially by the strange apelike beings who roamed its surface, totally unaware that they were simply part of a gigantic computer program. And this is very odd, because without that fairly simple and obvious piece of knowledge, nothing that ever happened on the Earth could possibly make the slightest bit of sense.

  9. The rise of ocean giants: maximum body size in Cenozoic marine mammals as an indicator for productivity in the Pacific and Atlantic Oceans.

    PubMed

    Pyenson, Nicholas D; Vermeij, Geerat J

    2016-07-01

    Large consumers have ecological influence disproportionate to their abundance, although this influence in food webs depends directly on productivity. Evolutionary patterns at geologic timescales inform expectations about the relationship between consumers and productivity, but it is very difficult to track productivity through time with direct, quantitative measures. Based on previous work that used the maximum body size of Cenozoic marine invertebrate assemblages as a proxy for benthic productivity, we investigated how the maximum body size of Cenozoic marine mammals, in two feeding guilds, evolved over comparable temporal and geographical scales. First, maximal size in marine herbivores remains mostly stable and occupied by two different groups (desmostylians and sirenians) over separate timeframes in the North Pacific Ocean, while sirenians exclusively dominated this ecological mode in the North Atlantic. Second, mysticete whales, which are the largest Cenozoic consumers in the filter-feeding guild, remained in the same size range until a Mio-Pliocene onset of cetacean gigantism. Both vertebrate guilds achieved very large size only recently, suggesting that different trophic mechanisms promoting gigantism in the oceans have operated in the Cenozoic than in previous eras. PMID:27381883

  10. The rise of ocean giants: maximum body size in Cenozoic marine mammals as an indicator for productivity in the Pacific and Atlantic Oceans

    PubMed Central

    Vermeij, Geerat J.

    2016-01-01

    Large consumers have ecological influence disproportionate to their abundance, although this influence in food webs depends directly on productivity. Evolutionary patterns at geologic timescales inform expectations about the relationship between consumers and productivity, but it is very difficult to track productivity through time with direct, quantitative measures. Based on previous work that used the maximum body size of Cenozoic marine invertebrate assemblages as a proxy for benthic productivity, we investigated how the maximum body size of Cenozoic marine mammals, in two feeding guilds, evolved over comparable temporal and geographical scales. First, maximal size in marine herbivores remains mostly stable and occupied by two different groups (desmostylians and sirenians) over separate timeframes in the North Pacific Ocean, while sirenians exclusively dominated this ecological mode in the North Atlantic. Second, mysticete whales, which are the largest Cenozoic consumers in the filter-feeding guild, remained in the same size range until a Mio-Pliocene onset of cetacean gigantism. Both vertebrate guilds achieved very large size only recently, suggesting that different trophic mechanisms promoting gigantism in the oceans have operated in the Cenozoic than in previous eras. PMID:27381883

  11. Urano y sus dos satélites irregulares recientemente descubiertos

    NASA Astrophysics Data System (ADS)

    Parisi, M. G.; Brunini, A.

    Hasta hace poco tiempo, Urano era el único de los Planetas Gigantes que no poseía satélites irregulares. Esto lo diferenciaba del resto de los planetas Gigantes, al igual que la peculiar oblicuidad de su eje de spin. La gran inclinación de su eje de rotación se debe probablemente a una colisión que sufrió el planeta con otro embrión planetario al final del proceso de formación. Esta colisión habría desligado satélites exteriores preexistentes del planeta. Recientemente se han descubierto dos satélites irregulares de Urano, lo que introduce algunas nuevas cotas y condiciones en el escenario de la "Hipótesis de la Gran Colisión" . Los satélites irregulares de Urano tuvieron que ser capturados en una etapa posterior a la del escenario de la Gran Colisión, de no ser así, hubieran sido eyectados del sistema por el impulso impartido con ese gran impacto. En este trabajo, se discuten los posibles mecanismos de captura de los satélites irregulares y se presenta un nuevo posible mecanismo para dicha captura.

  12. Upward electrical discharges observed above Tropical Depression Dorian.

    PubMed

    Liu, Ningyu; Spiva, Nicholas; Dwyer, Joseph R; Rassoul, Hamid K; Free, Dwayne; Cummer, Steven A

    2015-01-01

    Observation of upward electrical discharges from thunderstorms has been sporadically reported in the scientific literature. According to their terminal altitudes, they are classified as starters (20-30 km), jets (40-50 km) and gigantic jets (70-90 km). They not only have a significant impact on the occupied atmospheric volumes but also electrically couple different atmospheric regions. However, as they are rare and unpredictable, our knowledge of them has been built on observations that typically record only one type of such discharges. Here we report a close-distance observation of seven upward discharges including one starter, two jets and four gigantic jets above Tropical Depression Dorian. Our optical and electromagnetic data indicate that all events are of negative polarity, suggesting they are initiated in the same thundercloud charge region. The data also indicate that the lightning-like discharge channel can extend above thunderclouds by about 30 km, but the discharge does not emit low-frequency electromagnetic radiation as normal lightning. PMID:25607345

  13. Genomic comparison of closely related Giant Viruses supports an accordion-like model of evolution.

    PubMed

    Filée, Jonathan

    2015-01-01

    Genome gigantism occurs so far in Phycodnaviridae and Mimiviridae (order Megavirales). Origin and evolution of these Giant Viruses (GVs) remain open questions. Interestingly, availability of a collection of closely related GV genomes enabling genomic comparisons offer the opportunity to better understand the different evolutionary forces acting on these genomes. Whole genome alignment for five groups of viruses belonging to the Mimiviridae and Phycodnaviridae families show that there is no trend of genome expansion or general tendency of genome contraction. Instead, GV genomes accumulated genomic mutations over the time with gene gains compensating the different losses. In addition, each lineage displays specific patterns of genome evolution. Mimiviridae (megaviruses and mimiviruses) and Chlorella Phycodnaviruses evolved mainly by duplications and losses of genes belonging to large paralogous families (including movements of diverse mobiles genetic elements), whereas Micromonas and Ostreococcus Phycodnaviruses derive most of their genetic novelties thought lateral gene transfers. Taken together, these data support an accordion-like model of evolution in which GV genomes have undergone successive steps of gene gain and gene loss, accrediting the hypothesis that genome gigantism appears early, before the diversification of the different GV lineages. PMID:26136734

  14. Chromosome evolution with naked eye: Palindromic context of the life origin

    NASA Astrophysics Data System (ADS)

    Larionov, Sergei; Loskutov, Alexander; Ryadchenko, Eugeny

    2008-03-01

    Based on the representation of the DNA sequence as a two-dimensional (2D) plane walk, we consider the problem of identification and comparison of functional and structural organizations of chromosomes of different organisms. According to the characteristic design of 2D walks we identify telomere sites, palindromes of various sizes and complexity, areas of ribosomal RNA, transposons, as well as diverse satellite sequences. As an interesting result of the application of the 2D walk method, a new duplicated gigantic palindrome in the X human chromosome is detected. A schematic mechanism leading to the formation of such a duplicated palindrome is proposed. Analysis of a large number of the different genomes shows that some chromosomes (or their fragments) of various species appear as imperfect gigantic palindromes, which are disintegrated by many inversions and the mutation drift on different scales. A spread occurrence of these types of sequences in the numerous chromosomes allows us to develop a new insight of some accepted points of the genome evolution in the prebiotic phase.

  15. Genomic comparison of closely related Giant Viruses supports an accordion-like model of evolution

    PubMed Central

    Filée, Jonathan

    2015-01-01

    Genome gigantism occurs so far in Phycodnaviridae and Mimiviridae (order Megavirales). Origin and evolution of these Giant Viruses (GVs) remain open questions. Interestingly, availability of a collection of closely related GV genomes enabling genomic comparisons offer the opportunity to better understand the different evolutionary forces acting on these genomes. Whole genome alignment for five groups of viruses belonging to the Mimiviridae and Phycodnaviridae families show that there is no trend of genome expansion or general tendency of genome contraction. Instead, GV genomes accumulated genomic mutations over the time with gene gains compensating the different losses. In addition, each lineage displays specific patterns of genome evolution. Mimiviridae (megaviruses and mimiviruses) and Chlorella Phycodnaviruses evolved mainly by duplications and losses of genes belonging to large paralogous families (including movements of diverse mobiles genetic elements), whereas Micromonas and Ostreococcus Phycodnaviruses derive most of their genetic novelties thought lateral gene transfers. Taken together, these data support an accordion-like model of evolution in which GV genomes have undergone successive steps of gene gain and gene loss, accrediting the hypothesis that genome gigantism appears early, before the diversification of the different GV lineages. PMID:26136734

  16. Heat storage in Asian elephants during submaximal exercise: behavioral regulation of thermoregulatory constraints on activity in endothermic gigantotherms.

    PubMed

    Rowe, M F; Bakken, G S; Ratliff, J J; Langman, V A

    2013-05-15

    Gigantic size presents both opportunities and challenges in thermoregulation. Allometric scaling relationships suggest that gigantic animals have difficulty dissipating metabolic heat. Large body size permits the maintenance of fairly constant core body temperatures in ectothermic animals by means of gigantothermy. Conversely, gigantothermy combined with endothermic metabolic rate and activity likely results in heat production rates that exceed heat loss rates. In tropical environments, it has been suggested that a substantial rate of heat storage might result in a potentially lethal rise in core body temperature in both elephants and endothermic dinosaurs. However, the behavioral choice of nocturnal activity might reduce heat storage. We sought to test the hypothesis that there is a functionally significant relationship between heat storage and locomotion in Asian elephants (Elephas maximus), and model the thermoregulatory constraints on activity in elephants and a similarly sized migratory dinosaur, Edmontosaurus. Pre- and post-exercise (N=37 trials) measurements of core body temperature and skin temperature, using thermography were made in two adult female Asian elephants at the Audubon Zoo in New Orleans, LA, USA. Over ambient air temperatures ranging from 8 to 34.5°C, when elephants exercised in full sun, ~56 to 100% of active metabolic heat production was stored in core body tissues. We estimate that during nocturnal activity, in the absence of solar radiation, between 5 and 64% of metabolic heat production would be stored in core tissues. Potentially lethal rates of heat storage in active elephants and Edmontosaurus could be behaviorally regulated by nocturnal activity. PMID:23785105

  17. The maintenance of hybrids by parasitism in a freshwater snail.

    PubMed

    Guttel, Yonathan; Ben-Ami, Frida

    2014-11-01

    Hybrids have often been labelled evolutionary dead-ends due to their lower fertility and viability. However, there is growing awareness that hybridisation between different species may play a constructive role in animal evolution as a means to create variability. Thus, hybridisation and introgression may contribute to adaptive evolution, for example with regards to natural antagonists (parasites, predators, competitors) and adaptation to local environmental conditions. Here we investigated whether parasite intensity contributes to the continuous recreation of hybrids in 74 natural populations of Melanopsis, a complex of freshwater snails with three species. We also examined, under laboratory conditions, whether hybrids and their parental taxa differ in their tolerance of low and high temperatures and salinity levels. Infections were consistently less prevalent in males than in females, and lower in snails from deeper habitats. Infection prevalence in hybrids was significantly lower than in the parental taxa. Low hybrid infection rates could not be explained by sediment type, snail density or geographic distribution of the sampling sites. Interestingly, infected hybrid snails did not show signs of parasite-induced gigantism, whereas all parental taxa did. We found that hybrids mostly coped with extreme temperatures and salinity levels as well as their parental taxa did. Taken together, our results suggest that Melanopsis hybrids perform better in the presence of parasites and environmental stress. This may explain the widespread and long-term occurrence of Melanopsis hybrids as evidenced by paleontological and biogeographic data. Hybridisation may be an adaptive host strategy, reducing infection rates and resisting gigantism. PMID:25173837

  18. Impact of Frailty and Other Geriatric Syndromes on Clinical Management and Outcomes in Elderly Patients With Non-ST-Segment Elevation Acute Coronary Syndromes: Rationale and Design of the LONGEVO-SCA Registry.

    PubMed

    Alegre, Oriol; Ariza-Solé, Albert; Vidán, María T; Formiga, Francesc; Martínez-Sellés, Manuel; Bueno, Héctor; Sanchís, Juan; López-Palop, Ramón; Abu-Assi, Emad; Cequier, Àngel

    2016-07-01

    The incidence of acute coronary syndromes (ACS) is high in the elderly. Despite a high prevalence of frailty and other aging-related variables, little information exists about the optimal clinical management in patients with coexisting geriatric syndromes. The aim of the LONGEVO-SCA registry (Impacto de la Fragilidad y Otros Síndromes Geriátricos en el Manejo y Pronóstico Vital del Anciano con Síndrome Coronario Agudo sin Elevación de Segmento ST) is to assess the impact of aging-related variables on clinical management, prognosis, and functional status in elderly patients with ACS. A series of 500 consecutive octogenarian patients with non-ST-segment elevation ACS from 57 centers in Spain will be included. A comprehensive geriatric assessment will be performed during the admission, assessing functional status (Barthel Index, Lawton-Brody Index), frailty (FRAIL scale, Short Physical Performance Battery), comorbidity (Charlson Index), nutritional status (Mini Nutritional Assessment-Short Form), and quality of life (Seattle Angina Questionnaire). Patients will be managed according to current recommendations. The primary outcome will be the description of mortality and its causes at 6 months. Secondary outcomes will be changes in functional status and quality of life. Results from this study might significantly improve the knowledge about the impact of aging-related variables on management and outcomes of elderly patients with ACS. Clinical management of these patients has become a major health care problem due to the growing incidence of ACS in the elderly and its particularities. PMID:27362592

  19. Multiferroics with spiral spin orders.

    PubMed

    Tokura, Yoshinori; Seki, Shinichiro

    2010-04-12

    Cross correlation between magnetism and electricity in a solid can host magnetoelectric effects, such as magnetic (electric) induction of polarization (magnetization). A key to attain the gigantic magnetoelectric response is to find the efficient magnetism-electricity coupling mechanisms. Among those, recently the emergence of spontaneous (ferroelectric) polarization in the insulating helimagnet or spiral-spin structure was unraveled, as mediated by the spin-exchange and spin-orbit interactions. The sign of the polarization depends on the helicity (spin rotation sense), while the polarization direction itself depends on further details of the mechanism and the underlying lattice symmetry. Here, we describe some prototypical examples of the spiral-spin multiferroics, which enable some unconventional magnetoelectric control such as the magnetic-field-induced change of the polarization direction and magnitude as well as the electric-field-induced change of the spin helicity and magnetic domain. PMID:20496385

  20. Electric-field control of spin waves in multiferroic BiFeO3: Theory

    NASA Astrophysics Data System (ADS)

    de Sousa, Rogério; Rovillain, P.; Gallais, Y.; Sacuto, A.; Méasson, M. A.; Colson, D.; Forget, A.; Bibes, M.; Barthélémy, A.; Cazayous, M.

    2011-03-01

    Our recent experiment demonstrated gigantic (30%) electric-field tuning of magnon frequencies in multiferroic BiFeO3. We demonstrate that the origin of this effect is related to two linear magnetoelectric interactions that couple the component of electric field perpendicular to the ferroelectric vector to a quadratic form of the Néel vector. We calculate the magnon spectra due to each of these interactions and show that only one of them is consistent with experimental data. At high electric fields, this interaction induces a phase transition to a homogeneous state, and the multi-magnon spectra will fuse into two magnon frequencies. We discuss the possible microscopic mechanisms responsible for this novel interaction and the prospect for applications in magnonics. We acknowledge support from NSERC-Discovery (Canada) and the Agence Nationale pour la Recherche (France).

  1. Mega-island or micro-continent? New Zealand and its fauna.

    PubMed

    Daugherty, C H; Gibbs, G W; Hitchmough, R A

    1993-12-01

    The terrestrial New Zealand fauna has developed on an ancient landmass of continental origins that has had an increasingly isolated existence since the late Mesozoic. As a continental remnant, New Zealand harbours survivors of many ancient lineages many of which were once far more widely distributed. But New Zealand's fauna also resembles that of an isolated archipelago: many higher taxa are missing; some have undergone extensive radiations in situ; and levels of endemism approach 100% in many groups. Ecologically, the fauna is characterized by frequent niche shifts, gigantism, and extended life histories with low reproductive rates, factors that make many species vulnerable to human disturbance. Data continue to amass supporting the ecophysiological as well as phylogenetic distinctiveness of the fauna. Described taxonomic diversity, even of terrestrial vertebrates, continues to increase. PMID:21236224

  2. The Volcano Adventure Guide

    NASA Astrophysics Data System (ADS)

    Goff, Fraser

    2005-05-01

    Adventure travels to volcanoes offer chance encounters with danger, excitement, and romance, plus opportunities to experience scientific enlightenment and culture. To witness a violently erupting volcano and its resulting impacts on landscape, climate, and humanity is a powerful personal encounter with gigantic planetary forces. To study volcano processes and products during eruptions is to walk in the footsteps of Pliny himself. To tour the splendors and horrors of 25 preeminent volcanoes might be the experience of a lifetime, for scientists and nonscientists alike. In The Volcano Adventure Guide, we now have the ultimate tourist volume to lead us safely to many of the world's famous volcanoes and to ensure that we will see the important sites at each one.

  3. Fraud in the acid rain debate

    SciTech Connect

    Bagge, C.

    1984-06-01

    Electric utility executives, according to the author, and millions of other Americans are the victims of a gigantic fraud being carried on in the name of controlling acid rain. This fraud, states the author, involves the distorted, dire image of acidity in nature being created by environmental groups, politicians and others - to gain public sympathy for their legislative goals. The alleged fraud involves the very nature of the legislation being promoted as a low-cost cure for acid rain. On the basis of scientific evidence to date there is no assurance it will reduce acidity by any appreciable amount, but on the other hand it most certainly will cost users of electricity hundreds of billions of dollars in new costs. What has already happened to the nuclear industry is also meant for coal.

  4. Giant magneto-optical Raman effect in a layered transition metal compound

    PubMed Central

    Ji, Jianting; Zhang, Anmin; Fan, Jiahe; Li, Yuesheng; Wang, Xiaoqun; Zhang, Jiandi; Plummer, E. W.; Zhang, Qingming

    2016-01-01

    We report a dramatic change in the intensity of a Raman mode with applied magnetic field, displaying a gigantic magneto-optical effect. Using the nonmagnetic layered material MoS2 as a prototype system, we demonstrate that the application of a magnetic field perpendicular to the layers produces a dramatic change in intensity for the out-of-plane vibrations of S atoms, but no change for the in-plane breathing mode. The distinct intensity variation between these two modes results from the effect of field-induced broken symmetry on Raman scattering cross-section. A quantitative analysis on the field-dependent integrated Raman intensity provides a unique method to precisely determine optical mobility. Our analysis is symmetry-based and material-independent, and thus the observations should be general and inspire a new branch of inelastic light scattering and magneto-optical applications. PMID:26884198

  5. Woods: A fast and accurate functional annotator and classifier of genomic and metagenomic sequences.

    PubMed

    Sharma, Ashok K; Gupta, Ankit; Kumar, Sanjiv; Dhakan, Darshan B; Sharma, Vineet K

    2015-07-01

    Functional annotation of the gigantic metagenomic data is one of the major time-consuming and computationally demanding tasks, which is currently a bottleneck for the efficient analysis. The commonly used homology-based methods to functionally annotate and classify proteins are extremely slow. Therefore, to achieve faster and accurate functional annotation, we have developed an orthology-based functional classifier 'Woods' by using a combination of machine learning and similarity-based approaches. Woods displayed a precision of 98.79% on independent genomic dataset, 96.66% on simulated metagenomic dataset and >97% on two real metagenomic datasets. In addition, it performed >87 times faster than BLAST on the two real metagenomic datasets. Woods can be used as a highly efficient and accurate classifier with high-throughput capability which facilitates its usability on large metagenomic datasets. PMID:25863333

  6. Leaf development in Xylopia aromatica (Lam) Mart. (Annonaceae): implications for palatability to Stenoma scitiorella Walker 1864 (Lepidoptera: Elachistidae).

    PubMed

    Varanda, E M; Costa, A A; Barosela, J R

    2008-11-01

    Variations in specific foliar mass and water content, nitrogen, soluble carbohydrates and tannins were studied during the growth and maturation processes of the Xylopia aromatica leaves, to determine the effects of such alterations on the herbivory of Stenoma scitiorella caterpillars. This work was carried out in the physiognomy of the typical cerrado of the Parque Estadual de Vassununga, Gleba Pé-de Gigante, Santa Rita do Passa Quatro, São Paulo State, Brazil. While nutritional quality (water and nitrogen) decreases during expansion and maturation of Xylopia aromatica leaves, the chemical (tannins) and physical (sclerophylly) defenses are raised. In agreement with the observations on herbivory, the results support the hypothesis that the reduction in palatability and increase in chemical defenses of Xylopia aromatica leaves account for the caterpillars' preference for young expanding leaves. PMID:19197502

  7. Clinical Manifestations and Diagnosis of Acromegaly

    PubMed Central

    Lugo, Gloria; Pena, Lara; Cordido, Fernando

    2012-01-01

    Acromegaly and gigantism are due to excess GH production, usually as a result of a pituitary adenoma. The incidence of acromegaly is 5 cases per million per year and the prevalence is 60 cases per million. Clinical manifestations in each patient depend on the levels of GH and IGF-I, age, tumor size, and the delay in diagnosis. Manifestations of acromegaly are varied and include acral and soft tissue overgrowth, joint pain, diabetes mellitus, hypertension, and heart and respiratory failure. Acromegaly is a disabling disease that is associated with increased morbidity and reduced life expectancy. The diagnosis is based primarily on clinical features and confirmed by measuring GH levels after oral glucose loading and the estimation of IGF-I. It has been suggested that the rate of mortality in patients with acromegaly is correlated with the degree of control of GH. Adequately treated, the relative mortality risk can be markedly reduced towards normal. PMID:22518126

  8. Direct Determination of 3D Distribution of Elemental Composition in Single Semiconductor Nanoislands by Scanning Auger Microscopy.

    PubMed

    Ponomaryov, Semyon S; Yukhymchuk, Volodymyr O; Lytvyn, Peter M; Valakh, Mykhailo Ya

    2016-12-01

    An application of scanning Auger microscopy with ion etching technique and effective compensation of thermal drift of the surface analyzed area is proposed for direct local study of composition distribution in the bulk of single nanoislands. For GexSi1 - x-nanoislands obtained by MBE of Ge on Si-substrate gigantic interdiffusion mixing takes place both in the open and capped nanostructures. Lateral distributions of the elemental composition as well as concentration-depth profiles were recorded. 3D distribution of the elemental composition in the d-cluster bulk was obtained using the interpolation approach by lateral composition distributions in its several cross sections and concentration-depth profile. It was shown that there is a germanium core in the nanoislands of both nanostructure types, which even penetrates the substrate. In studied nanostructures maximal Ge content in the nanoislands may reach about 40 at.%. PMID:26909783

  9. Quantifying volcanic ash dispersal and impact of the Campanian Ignimbrite super-eruption

    NASA Astrophysics Data System (ADS)

    Costa, A.; Folch, A.; Macedonio, G.; Giaccio, B.; Isaia, R.; Smith, V. C.

    2012-05-01

    We apply a novel computational approach to assess, for the first time, volcanic ash dispersal during the Campanian Ignimbrite (Italy) super-eruption providing insights into eruption dynamics and the impact of this gigantic event. The method uses a 3D time-dependent computational ash dispersion model, a set of wind fields, and more than 100 thickness measurements of the CI tephra deposit. Results reveal that the CI eruption dispersed 250-300 km3 of ash over ˜3.7 million km2. The injection of such a large quantity of ash (and volatiles) into the atmosphere would have caused a volcanic winter during the Heinrich Event 4, the coldest and driest climatic episode of the Last Glacial period. Fluorine-bearing leachate from the volcanic ash and acid rain would have further affected food sources and severely impacted Late Middle-Early Upper Paleolithic groups in Southern and Eastern Europe.

  10. On the fate of pumice rafts formed during the 2012 Havre submarine eruption

    PubMed Central

    Jutzeler, Martin; Marsh, Robert; Carey, Rebecca J.; White, James D. L.; Talling, Peter J.; Karlstrom, Leif

    2014-01-01

    Pumice rafts are floating mobile accumulations of low-density pumice clasts generated by silicic volcanic eruptions. Pumice in rafts can drift for years, become waterlogged and sink, or become stranded on shorelines. Here we show that the pumice raft formed by the impressive, deep submarine eruption of the Havre caldera volcano (Southwest Pacific) in July 2012 can be mapped by satellite imagery augmented by sailing crew observations. Far from coastal interference, the eruption produced a single >400 km2 raft in 1 day, thus initiating a gigantic, high-precision, natural experiment relevant to both modern and prehistoric oceanic surface dispersal dynamics. Observed raft dispersal can be accurately reproduced by simulating drift and dispersal patterns using currents from an eddy-resolving ocean model hindcast. For future eruptions that produce potentially hazardous pumice rafts, our technique allows real-time forecasts of dispersal routes, in addition to inference of ash/pumice deposit distribution in the deep ocean. PMID:24755668

  11. Ethics in Thought. Gian-Carlo Rota and Philosophy

    NASA Astrophysics Data System (ADS)

    Bonicalzi, Francesca

    Discrete Thoughts - Pensieri discreti, where "discreti" means both discrete and discreet: the title announces, with surprising clearness, and simultaneously conceals, with ingenious ambivalence, the gigantic feat Rota intends to perform: "to tell the truth". Although it is, classically, the philosopher's task, telling the truth is proclaimed from the outset as the - difficult/impossible? - enterprise of the mathematician. "In mathematics, as anywhere today, it is becoming more difficult to tell the truth" (Rota, 1986, p. IX): these are the first words of the preface to Discrete Thoughts, and they ring out as a provocation and a challenge that presents itself as particularly difficult due to the complexity of the wealth of knowledge that mathematics represents, but also due to the persistence in the sciences of a reductive conception of truth.

  12. Zelda and company - Petrogenesis of sulfide-rich Fremdlinge and constraints on solar nebula processes

    NASA Technical Reports Server (NTRS)

    Armstrong, John T.; Hutcheon, Ian D.; Wasserburg, G. J.

    1987-01-01

    A detailed petrographic and chemical study of Zelda (a gigantic sulfide-rich Fremdling from the Allende Ca-rich inclusion, CAI, Egg 6) and its contact with the host was conducted using analytical SEM and electron-microprobe techniques, and the results were compared with those obtained on other sulfide-rich and oxide-rich Fremdlinge. Strong evidence is presented that Zelda, a type-example of sulfide-rich Fremdlinge, has been formed from a preexisting Ur-Fremdling, similar by composition to Willy, by closed-system sulfidization of magnetite and metal. At least two different sulfidization mechanisms appear to have occurred in altering Fremdlinge: one producing compositionally homogeneous equigranular objects such as Zelda, the other producing compositionally and texturally heterogeneous objects.

  13. Bilateral renal dysplasia, nephroblastomatosis, and bronchial stenosis. A new syndrome?

    PubMed

    Rodriguez, Maria Matilde; Correa-Medina, Mayrin; Whittington, Elizabeth E

    2015-06-01

    Bilateral nephroblastomatosis (NB) is an uncommon renal anomaly characterized by multiple confluent nephrogenic rests scattered through both kidneys, with only a limited number of cases reported in the medical literature. Some of these children may have associated either Perlman or Beckwith-Wiedemann syndrome and others do not demonstrate syndromic features. We report a full-term boy with anteverted nose, bilateral bronchial stenosis due to lack of cartilage, bilateral obstructive renal dysplasia and NB with glomeruloid features. The infant had visceromegaly, but neither gigantism nor hemihypertrophy. Immunohistochemistry for PAX2 (Paired box gene-2) and WT-1 (Wilms Tumor 1) were strongly positive in the areas of NB. GLEPP-1 (Glomerular Epithelial Protein) did not stain the areas of NB with a glomeruloid appearance, but was positive in the renal glomeruli as expected. We found neither associated bronchial stenosis nor the histology of NB resembling giant glomeruli in any of the reported cases of NB. PMID:25871299

  14. Magnetic biasing of a ferroelectric hysteresis loop in a multiferroic orthoferrite.

    PubMed

    Tokunaga, Y; Taguchi, Y; Arima, T; Tokura, Y

    2014-01-24

    In a multiferroic orthoferrite Dy0.7Tb0.3FeO3, which shows electric-field-(E-)driven magnetization (M) reversal due to a tight clamping between polarization (P) and M, a gigantic effect of magnetic-field (H) biasing on P-E hysteresis loops is observed in the case of rapid E sweeping. The magnitude of the bias E field can be controlled by varying the magnitude of H, and its sign can be reversed by changing the sign of H or the relative clamping direction between P and M. The origin of this unconventional biasing effect is ascribed to the difference in the Zeeman energy between the +P and -P states coupled with the M states with opposite sign. PMID:24484164

  15. The supergiant amphipod Alicella gigantea (Crustacea: Alicellidae) from hadal depths in the Kermadec Trench, SW Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Jamieson, A. J.; Lacey, N. C.; Lörz, A.-N.; Rowden, A. A.; Piertney, S. B.

    2013-08-01

    Here we provide the first record of the 'supergiant' amphipod Alicella gigantea Chevreux, 1899 (Alicellidae) from the Southern Hemisphere, and extend the known bathymetric range by over 1000 m to 7000 m. An estimated nine individuals were observed across 1500 photographs taken in situ by baited camera at 6979 m in the Kermadec Trench, SW Pacific Ocean. Nine specimens, ranging in length from 102 to 290 mm were recovered by baited trap at depths of 6265 m and 7000 m. Mitochondrial and nuclear DNA sequences obtained indicate a cosmopolitan distribution for the species. Data and observations from the study are used to discuss the reason for gigantism in this species, and its apparently disjunct geographical distribution.

  16. Giant magneto-optical Raman effect in a layered transition metal compound.

    PubMed

    Ji, Jianting; Zhang, Anmin; Fan, Jiahe; Li, Yuesheng; Wang, Xiaoqun; Zhang, Jiandi; Plummer, E W; Zhang, Qingming

    2016-03-01

    We report a dramatic change in the intensity of a Raman mode with applied magnetic field, displaying a gigantic magneto-optical effect. Using the nonmagnetic layered material MoS2 as a prototype system, we demonstrate that the application of a magnetic field perpendicular to the layers produces a dramatic change in intensity for the out-of-plane vibrations of S atoms, but no change for the in-plane breathing mode. The distinct intensity variation between these two modes results from the effect of field-induced broken symmetry on Raman scattering cross-section. A quantitative analysis on the field-dependent integrated Raman intensity provides a unique method to precisely determine optical mobility. Our analysis is symmetry-based and material-independent, and thus the observations should be general and inspire a new branch of inelastic light scattering and magneto-optical applications. PMID:26884198

  17. 6Li-loaded directionally sensitive anti-neutrino detector for possible geo-neutrinographic imaging applications

    NASA Astrophysics Data System (ADS)

    Tanaka, H. K. M.; Watanabe, H.

    2014-04-01

    Despite the latent and unique benefits of imaging uranium and thorium's distribution in the earth's interior, previously proposed experimental techniques used to identify the incoming geo-neutrino's direction are not applicable to practical imaging due to the high miss-identification in a neutrino's track reconstruction. After performing experimental studies and Monte-Carlo simulations, we confirmed that a significant improvement is possible in neutrino tracking identification with a 6Li-loaded neutrino detector. For possible imaging applications, we also explore the feasibility of producing geo-neutrinographic images of gigantic magmatic reservoirs and deep structure in the mantle. We anticipate and plan to apply these newly designed detectors to radiographic imaging of the Earth's interior, monitoring of nuclear reactors, and tracking astrophysical sources of neutrinos.

  18. 6Li-loaded directionally sensitive anti-neutrino detector for possible geo-neutrinographic imaging applications

    PubMed Central

    Tanaka, H. K. M.; Watanabe, H.

    2014-01-01

    Despite the latent and unique benefits of imaging uranium and thorium's distribution in the earth's interior, previously proposed experimental techniques used to identify the incoming geo-neutrino's direction are not applicable to practical imaging due to the high miss-identification in a neutrino's track reconstruction. After performing experimental studies and Monte-Carlo simulations, we confirmed that a significant improvement is possible in neutrino tracking identification with a 6Li-loaded neutrino detector. For possible imaging applications, we also explore the feasibility of producing geo-neutrinographic images of gigantic magmatic reservoirs and deep structure in the mantle. We anticipate and plan to apply these newly designed detectors to radiographic imaging of the Earth's interior, monitoring of nuclear reactors, and tracking astrophysical sources of neutrinos. PMID:24759616

  19. Interlayer Coupling and Dielectric Anomaly in Ferroelectric Bilayers and Multilayer Heterostructures

    NASA Astrophysics Data System (ADS)

    Pamir Alpay, S.; Zhong, Shan; Roytburd, Alexander L.; Mantese, Joseph V.

    2006-03-01

    Ferroelectric multilayers and superlattices have gained interest for dynamic random access memory (DRAM) applications and as active elements in tunable microwave devices in the telecommunications industry. There have been a number of experimental studies that show that these materials have many peculiar properties that cannot be described by a simple series connection of the individual layers that make up the heterostructures. A thermodynamic analysis is presented to demonstrate that ferroelectric multilayers interact through internal elastic, electrical, and electromechanical fields and the ``strength'' of the coupling can be quantitatively described using Landau theory of phase transformations, theory of elasticity, and principles of electrostatics. The thermodynamic modeling indicates that the electrostatic coupling between the layers leads to the suppression of ferroelectricity at a critical paraelectric layer thickness for ferroelectric-paraelectric bilayers. This bilayer is expected to have a gigantic dielectric response similar to the dielectric anomaly near Curie-Weiss temperature in homogeneous ferroelectrics at this critical thickness.

  20. TLEs and their electromagnetic characteristics from 2010 Taiwan ground campaign

    NASA Astrophysics Data System (ADS)

    Huang, S.; Chen, A. B.; Chou, J.; Lee, L.; Chang, S.; Wu, Y.; Lee, Y.; Hsu, C.; Yang, G.; Kuo, C.; Su, H.; Hsu, R.

    2010-12-01

    Hundreds of transient luminous events (TLEs), including sprites, elves, halos, blue jets, and several interesting gigantic jets are captured during Taiwan 2010 ground campaign. Most of the associated sferics of these TLEs was recorded simultaneously by a ULF recording system located at Mt. Lulin [Wang et al., 2005; two EMI-BF4 magnetic coils] and a newly-installed ELF/VLF Quasar system. To suppress strong 60-Hz power grid emissions, both systems are equipped with notch-filtering signal modulators. Inevitably, phase and waveform of the sferics passing through these modulators will be altered. A waveform reconstruction method is developed to restore the waveform distortion and the phase shift to a satisfactory level. Electromagnetic characteristics of the TLE-associated sferics and the TLE-producing lightning are inferred from the reconstructed sferics. The paper will report the recorded TLEs, the associated sferics, and the inferred physical characteristics.

  1. Size-, electric-field-, and frequency-dependent third-order nonlinear optical properties of hydrogenated silicon nanoclusters

    NASA Astrophysics Data System (ADS)

    Li, Haipeng; Xu, Hu; Shen, Xiaopeng; Han, Kui; Bi, Zetong; Xu, Runfeng

    2016-06-01

    We investigated the electronic properties and second hyperpolarizabilities of hydrogenated silicon nanoclusters (H-SiNCs) by using the density functional theory method. The effects of cluster size, external electric field and incident frequency on the second hyperpolarizability were also examined, respectively. We found that small H-SiNCs exhibit large second hyperpolarizability. With the increase of the number of silicon atoms in H-SiNCs, the frontier molecular orbital energy gap decreases, attributed to the enhancement of the second hyperpolarizability. Interestingly, we also found the electric-field-induced gigantic enhancement of the second hyperpolarizability for H-SiNCs due to the change of electron density distributions. In addition, our results demonstrate a significant dependence on the frequency of incident light.

  2. Ancient DNA reveals elephant birds and kiwi are sister taxa and clarifies ratite bird evolution.

    PubMed

    Mitchell, Kieren J; Llamas, Bastien; Soubrier, Julien; Rawlence, Nicolas J; Worthy, Trevor H; Wood, Jamie; Lee, Michael S Y; Cooper, Alan

    2014-05-23

    The evolution of the ratite birds has been widely attributed to vicariant speciation, driven by the Cretaceous breakup of the supercontinent Gondwana. The early isolation of Africa and Madagascar implies that the ostrich and extinct Madagascan elephant birds (Aepyornithidae) should be the oldest ratite lineages. We sequenced the mitochondrial genomes of two elephant birds and performed phylogenetic analyses, which revealed that these birds are the closest relatives of the New Zealand kiwi and are distant from the basal ratite lineage of ostriches. This unexpected result strongly contradicts continental vicariance and instead supports flighted dispersal in all major ratite lineages. We suggest that convergence toward gigantism and flightlessness was facilitated by early Tertiary expansion into the diurnal herbivory niche after the extinction of the dinosaurs. PMID:24855267

  3. Facility for platforms planned in Tacoma

    SciTech Connect

    Not Available

    1984-11-01

    A joint venture to build a gigantic 660-ft-wide graving dock for constructing offshore concrete and steel platforms on the US West Coast in Tacoma, Washington is discussed. The new facility is needed to construct huge platforms for Alaska and for deepwater locations off California and Mexico. The assembly facility would be located in Tacoma's Commencement Bay Industrial Development District on the outer Hylebos Waterway, directly across the waterway from Tacoma Boatbuilding Co.'s Industrial Yard. The proposed site has no overhead obstructions and open water all the way to the Pacific Ocean. Water depths in Commencement Bay are over 500 ft, making it possible to build deepwater concrete-gravity platforms.

  4. Giant Optical Polarization Rotation Induced by Spin-Orbit Coupling in Polarons

    NASA Astrophysics Data System (ADS)

    Casals, Blai; Cichelero, Rafael; García Fernández, Pablo; Junquera, Javier; Pesquera, David; Campoy-Quiles, Mariano; Infante, Ingrid C.; Sánchez, Florencio; Fontcuberta, Josep; Herranz, Gervasi

    2016-07-01

    We have uncovered a giant gyrotropic magneto-optical response for doped ferromagnetic manganite La2 /3Ca1 /3MnO3 around the near room-temperature paramagnetic-to-ferromagnetic transition. At odds with current wisdom, where this response is usually assumed to be fundamentally fixed by the electronic band structure, we point to the presence of small polarons as the driving force for this unexpected phenomenon. We explain the observed properties by the intricate interplay of mobility, Jahn-Teller effect, and spin-orbit coupling of small polarons. As magnetic polarons are ubiquitously inherent to many strongly correlated systems, our results provide an original, general pathway towards the generation of magnetic-responsive gigantic gyrotropic responses that may open novel avenues for magnetoelectric coupling beyond the conventional modulation of magnetization.

  5. Lightning and middle atmospheric discharges in the atmosphere

    NASA Astrophysics Data System (ADS)

    Siingh, Devendraa; Singh, R. P.; Kumar, Sarvan; Dharmaraj, T.; Singh, Abhay K.; Singh, Ashok K.; Patil, M. N.; Singh, Shubha

    2015-11-01

    Recent development in lightning discharges including transient luminous events (TLEs) and global electric circuit are discussed. Role of solar activity, convective available potential energy, surface temperature and difference of land-ocean surfaces on convection process are discussed. Different processes of discharge initiation are discussed. Events like sprites and halos are caused by the upward quasi-electrostatic fields associated with intense cloud-to-ground discharges while jets (blue starter, blue jet, gigantic jet) are caused by charge imbalance in thunderstorm during lightning discharges but they are not associated with a particular discharge flash. Elves are generated by the electromagnetic pulse radiated during lightning discharges. The present understanding of global electric circuit is also reviewed. Relation between lightning activity/global electric circuit and climate is discussed.

  6. 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.

  7. The Intersection of Urban Planning, Art, and Public Health: The Sunnyside Piazza

    PubMed Central

    Semenza, Jan C.

    2003-01-01

    Deteriorating physical features of urban environments can negatively influence public health. Dilapidated environments and urban blight tend to promote alienation and can be associated with social disorder, vandalism, crime, drug abuse, traffic violations, and littering, which in turn affects health and well-being. In the late 1990s, the Sunnyside neighborhood in Portland, Ore, was plagued by many of these problems. In an attempt to invigorate neighborhood stewardship, the community organized and created a public gathering place; together, they painted a gigantic sunflower in the middle of an intersection and installed several interactive art features. As a result of these collective actions of “place-making,” social capital has increased, thus revitalizing the community, and expanded social networks among residents have stimulated a sense of well-being. PMID:12948959

  8. The gravitational resolving power of global seismic networks in the 0.1-10 Hz band

    NASA Astrophysics Data System (ADS)

    Mulargia, Francesco; Kamenshchik, Alexander

    2016-04-01

    Among the first attempts to detect gravitational waves, the seismic approach pre-dates the digital era. Major advances in computational power, seismic instrumentation and in the knowledge of seismic noise suggest to reappraise its potential. Using the whole earth as a detector, with the thousands of digital seismometers of seismic global networks as a single phased array, more than two decades of continuous seismic noise data are available and can be readily sifted at the only cost of (a pretty gigantic) computation. Using a subset of data, we show that absolute strains h ≲10-17 on burst gravitational pulses and h ≲10-21 on periodic signals may be feasibly resolved in the frequency range 0.1-10 Hz, only marginally covered by current advanced LIGO and future eLISA. However, theoretical predictions for the largest cosmic gravitational emissions at these frequencies are a few orders of magnitude lower.

  9. Pressure variation of Rashba spin splitting toward topological transition in the polar semiconductor BiTeI

    NASA Astrophysics Data System (ADS)

    Ideue, T.; Checkelsky, J. G.; Bahramy, M. S.; Murakawa, H.; Kaneko, Y.; Nagaosa, N.; Tokura, Y.

    2014-10-01

    BiTeI is a polar semiconductor with gigantic Rashba spin-split bands in bulk. We have investigated the effect of pressure on the electronic structure of this material via magnetotransport. Periods of Shubunikov-de Haas (SdH) oscillations originating from the spin-split outer Fermi surface and inner Fermi surface show disparate responses to pressure, while the carrier number derived from the Hall effect is unchanged with pressure. The associated parameters which characterize the spin-split band structure are strongly dependent on pressure, reflecting the pressure-induced band deformation. We find the SdH oscillations and transport response are consistent with the theoretically proposed pressure-induced band deformation leading to a topological phase transition. Our analysis suggests the critical pressure for the quantum phase transition near Pc=3.5 GPa.

  10. A Graph Summarization Algorithm Based on RFID Logistics

    NASA Astrophysics Data System (ADS)

    Sun, Yan; Hu, Kongfa; Lu, Zhipeng; Zhao, Li; Chen, Ling

    Radio Frequency Identification (RFID) applications are set to play an essential role in object tracking and supply chain management systems. The volume of data generated by a typical RFID application will be enormous as each item will generate a complete history of all the individual locations that it occupied at every point in time. The movement trails of such RFID data form gigantic commodity flowgraph representing the locations and durations of the path stages traversed by each item. In this paper, we use graph to construct a warehouse of RFID commodity flows, and introduce a database-style operation to summarize graphs, which produces a summary graph by grouping nodes based on user-selected node attributes, further allows users to control the hierarchy of summaries. It can cut down the size of graphs, and provide convenience for users to study just on the shrunk graph which they interested. Through extensive experiments, we demonstrate the effectiveness and efficiency of the proposed method.

  11. From paper drawings to computer-aided design

    NASA Astrophysics Data System (ADS)

    Karima, M.; Sadhal, K. S.; McNeil, T. O.

    1985-02-01

    The benefits of a fully integrated computer-aided design and drafting system (CADDS) database are today very well accepted by industry, and major engineering companies implementing CADDS are confronted with the gigantic task of entering the existing multidisciplinary engineering information into the CADDS database. The present investigation is concerned with the findings of a feasibility study which had been conducted by a Canadian company to explore data capture on engineering drawings. A review of the state of the art in digitization is presented, and attention is given to specific problems arising in the case of the Canadian company. It is found that substantial advancements have been made toward the automatic 'reading' of existing drawings on paper media. However, no system exists currently which fully automates the data capturing process in the engineering environment and generates intelligent databases for use by CADD systems. Suitable approaches for 'data capture' under the given conditions are discussed.

  12. Armageddon, oil, and the Middle East crisis

    SciTech Connect

    Walvoord, J.F.; Walvoord, J.E.

    1980-01-01

    This book relates the intricate subject of biblical prophecy to the current crisis in the Middle East. With the development of oil politics, Dr. Walvoord believes a new world government will emerge, centered in the Middle East, which will eclipse the United States and Russia as world powers. The world government will be subjected to catastrophic, divine judgments which precipitate a gigantic world war culminating in Armageddon. Each chapter is devoted to the scriptural explanations of events leading to the second coming of Christ. The result is a prophetic calendar summing up to the countdown to Armageddon. Some of the chapter titles include: the Arab oil blackmail; watch Jerusalen; the rising tide of world religion; the coming Middle East peace; the coming world dictator; and Armageddon: the world's death struggle.

  13. On the collective appearance of coronal loops and the resistive heating instability

    NASA Astrophysics Data System (ADS)

    Lou, Yu-Qing

    We investigate the onset conditions for direct resistive heating instabilities coupled with radiative processes within a twisted magnetic flux rope of axisymmetry and relate the helical patterns wrapping along the rope initiated by such instabilities to the collective appearance of compact X-ray loops in a certain phase of active region development in the solar corona. Since the emergence and the subsequent evolution of a gigantic magnetic flux rope in the solar atmosphere involve complicated physical processes, it is expected that such instabilities occurring in an ensemble of many current sheaths embedded in a stressed, twisted, and bulged magnetic flux rope will manifest as collective X-ray loop structures on various spatial scales and with varieties of large-scale morphologies.

  14. 3D Reconstruction of the Source and Scale of Buried Young Flood Channels on Mars

    NASA Astrophysics Data System (ADS)

    Morgan, Gareth A.; Campbell, Bruce A.; Carter, Lynn M.; Plaut, Jeffrey J.; Phillips, Roger J.

    2013-05-01

    Outflow channels on Mars are interpreted as the product of gigantic floods due to the catastrophic eruption of groundwater that may also have initiated episodes of climate change. Marte Vallis, the largest of the young martian outflow channels (<500 million years old), is embayed by lava flows that hinder detailed studies and comparisons with older channel systems. Understanding Marte Vallis is essential to our assessment of recent Mars hydrologic activity during a period otherwise considered to be cold and dry. Using data from the Shallow Radar sounder on the Mars Reconnaissance Orbiter, we present a three-dimensional (3D) reconstruction of buried channels on Mars and provide estimates of paleohydrologic parameters. Our work shows that Cerberus Fossae provided the waters that carved Marte Vallis, and it extended an additional 180 kilometers to the east before the emplacement of the younger lava flows. We identified two stages of channel incision and determined that channel depths were more than twice those of previous estimates.

  15. Comparative 3D analyses and palaeoecology of giant early amphibians (Temnospondyli: Stereospondyli)

    PubMed Central

    Fortuny, Josep; Marcé-Nogué, Jordi; Steyer, J.-Sébastien; de Esteban-Trivigno, Soledad; Mujal, Eudald; Gil, Lluís

    2016-01-01

    Macroevolutionary, palaeoecological and biomechanical analyses in deep time offer the possibility to decipher the structural constraints, ecomorphological patterns and evolutionary history of extinct groups. Here, 3D comparative biomechanical analyses of the extinct giant early amphibian group of stereospondyls together with living lissamphibians and crocodiles, shows that: i) stereospondyls had peculiar palaeoecological niches with proper bites and stress patterns very different than those of giant salamanders and crocodiles; ii) their extinction may be correlated with the appearance of neosuchians, which display morphofunctional innovations. Stereospondyls weathered the end-Permian mass extinction, re-radiated, acquired gigantic sizes and dominated (semi) aquatic ecosystems during the Triassic. Because these ecosystems are today occupied by crocodilians, and stereospondyls are extinct amphibians, their palaeobiology is a matter of an intensive debate: stereospondyls were a priori compared with putative living analogous such as giant salamanders and/or crocodilians and our new results try to close this debate. PMID:27457883

  16. Introduction to Plasma Dynamo, Reconnection and Shocks

    SciTech Connect

    Intrator, Thomas P.

    2012-08-30

    In our plasma universe, most of what we can observe is composed of ionized gas, or plasma. This plasma is a conducting fluid, which advects magnetic fields when it flows. Magnetic structure occurs from the smallest planetary to the largest cosmic scales. We introduce at a basic level some interesting features of non linear magnetohydrodynamics (MHD). For example, in our plasma universe, dynamo creates magnetic fields from gravitationally driven flow energy in an electrically conducting medium, and conversely magnetic reconnection annihilates magnetic field and accelerates particles. Shocks occur when flows move faster than the local velocity (sonic or Alfven speed) for the propagation of information. Both reconnection and shocks can accelerate particles, perhaps to gigantic energies, for example as observed with 10{sup 20} eV cosmic rays.

  17. Total Hip Arthroplasty Using a Polished Tapered Cemented Stem in Hereditary Multiple Exostosis

    PubMed Central

    Kanda, Akio; Kaneko, Kazuo; Obayashi, Osamu; Mogami, Atsuhiko

    2016-01-01

    A 61-year-old Japanese man underwent right total hip arthroplasty for hereditary multiple exostosis. At first presentation, he had suffered from coxalgia for a long time. On radiographic images, there was a gigantic femoral head, increased shaft angle, and large diameter of the femoral neck. He had also developed coxarthrosis and severe pain of the hip joint. The transformation of the proximal femur bone causes difficulty in setting a cementless total hip prosthesis. Therefore, total hip arthroplasty using a cemented polished tapered stem was performed via a direct lateral approach. Using a cemented polished tapered stem allowed us to deal with the femoral bone transformation and bone substance defectiveness due to exostosis and also minimized the invasiveness of the operation. PMID:27127668

  18. Eating and digesting "Lestrygonians": a physiological model of reading.

    PubMed

    Yared, Aida

    2008-01-01

    In this article, I propose that, beneath a deceptively simple story-line, "Lestrygonians" functions like a living entity, one through which Bloom unknowingly traverses. First, there is Joyce's familiar Dublin, on a macroscopic level, and, second, there is the episode's narrative, personified by a gigantic female organism, in whose digestive tract Bloom has been reduced to Lilliputian size. Some critics have noted the importance of the physiological details of digestion here; no one, however, has noted to what extent the structure of the episode is represented by the digestive model. My final claim about the episode's digestive proclivities concerns its effects on the reader. If "Lestrygonians" replicates alimentary functions by propelling both its characters and the reading process along, it also elicits, in the reader, the synesthesia of reading with autonomic sensations. PMID:20836271

  19. ⁶Li-loaded directionally sensitive anti-neutrino detector for possible geo-neutrinographic imaging applications.

    PubMed

    Tanaka, H K M; Watanabe, H

    2014-01-01

    Despite the latent and unique benefits of imaging uranium and thorium's distribution in the earth's interior, previously proposed experimental techniques used to identify the incoming geo-neutrino's direction are not applicable to practical imaging due to the high miss-identification in a neutrino's track reconstruction. After performing experimental studies and Monte-Carlo simulations, we confirmed that a significant improvement is possible in neutrino tracking identification with a (6)Li-loaded neutrino detector. For possible imaging applications, we also explore the feasibility of producing geo-neutrinographic images of gigantic magmatic reservoirs and deep structure in the mantle. We anticipate and plan to apply these newly designed detectors to radiographic imaging of the Earth's interior, monitoring of nuclear reactors, and tracking astrophysical sources of neutrinos. PMID:24759616

  20. How hottest geometries and adsorptive parameters influence the SER(R)S spectra of Methylene Blue molecules adsorbed on nanocolloidal gold particles of varied sizes?

    PubMed

    Roy, Sannak Dutta; Ghosh, Manash; Chowdhury, Joydeep

    2015-12-01

    The SER(R)S spectra of Methylene Blue (MB) molecule adsorbed on gold nanocolloidal particles (AuNCs) have been investigated. The adsorptive parameters of the molecule adsorbed on AuNCs have been evaluated with the aid of Fluorescence Spectroscopy study. Fluorescence spectroscopic studies have been further applied to understand the concentration of probe molecule actually adsorbed on AuNC surfaces. Gigantic enhancements ∼10(6)-10(16) orders of magnitude have been recorded for the enhanced Raman bands in the SER(R)S spectra. Three-dimensional Finite Difference Time Domain (3D-FDTD) simulations studies have been carried out to predict the distributions of electric fields around the possible nanoaggregated hot geometries considered to be responsible for the huge enhancements of SER(R)S bands of the MB molecule. PMID:26172467

  1. On the fate of pumice rafts formed during the 2012 Havre submarine eruption

    NASA Astrophysics Data System (ADS)

    Jutzeler, Martin; Marsh, Robert; Carey, Rebecca J.; White, James D. L.; Talling, Peter J.; Karlstrom, Leif

    2014-04-01

    Pumice rafts are floating mobile accumulations of low-density pumice clasts generated by silicic volcanic eruptions. Pumice in rafts can drift for years, become waterlogged and sink, or become stranded on shorelines. Here we show that the pumice raft formed by the impressive, deep submarine eruption of the Havre caldera volcano (Southwest Pacific) in July 2012 can be mapped by satellite imagery augmented by sailing crew observations. Far from coastal interference, the eruption produced a single >400 km2 raft in 1 day, thus initiating a gigantic, high-precision, natural experiment relevant to both modern and prehistoric oceanic surface dispersal dynamics. Observed raft dispersal can be accurately reproduced by simulating drift and dispersal patterns using currents from an eddy-resolving ocean model hindcast. For future eruptions that produce potentially hazardous pumice rafts, our technique allows real-time forecasts of dispersal routes, in addition to inference of ash/pumice deposit distribution in the deep ocean.

  2. Crystal structure of Streptococcus pneumoniae pneumolysin provides key insights into early steps of pore formation

    PubMed Central

    Lawrence, Sara L.; Feil, Susanne C.; Morton, Craig J.; Farrand, Allison J.; Mulhern, Terrence D.; Gorman, Michael A.; Wade, Kristin R.; Tweten, Rodney K.; Parker, Michael W.

    2015-01-01

    Pore-forming proteins are weapons often used by bacterial pathogens to breach the membrane barrier of target cells. Despite their critical role in infection important structural aspects of the mechanism of how these proteins assemble into pores remain unknown. Streptococcus pneumoniae is the world’s leading cause of pneumonia, meningitis, bacteremia and otitis media. Pneumolysin (PLY) is a major virulence factor of S. pneumoniae and a target for both small molecule drug development and vaccines. PLY is a member of the cholesterol-dependent cytolysins (CDCs), a family of pore-forming toxins that form gigantic pores in cell membranes. Here we present the structure of PLY determined by X-ray crystallography and, in solution, by small-angle X-ray scattering. The crystal structure reveals PLY assembles as a linear oligomer that provides key structural insights into the poorly understood early monomer-monomer interactions of CDCs at the membrane surface. PMID:26403197

  3. Mass extinctions and cosmic collisions - A lunar test

    NASA Technical Reports Server (NTRS)

    Horz, F.

    1985-01-01

    The possibility has been considered that some or all major mass extinctions in the geologic record of earth are caused by the collision of massive, cosmic objects. Thus, it has been proposed that the unusual concentration of siderophile elements in strata at which the boundary between the Cretaceous (K) and Tertiary (T) geologic time periods has been placed must represent the remnants of a gigantic meteorite. However, a large 65-m.y.-old crater which could have been the result of the impact of this meteorite is not presently known on earth. One approach to evaluate the merits of the collisional hypothesis considered is based on the study of the probability of collision between a cosmic object of a suitable size and the earth. As moon and earth were subject to the same bombardment history and the preservation of craters on the moon is much better than on earth, a consideration of the lunar cratering record may provide crucial information.

  4. The skull of the giant predatory pliosaur Rhomaleosaurus cramptoni: implications for plesiosaur phylogenetics

    NASA Astrophysics Data System (ADS)

    Smith, Adam S.; Dyke, Gareth J.

    2008-10-01

    The predatory pliosaurs were among the largest creatures ever to inhabit the oceans, some reaching gigantic proportions greater than 15 m in length. Fossils of this subclade of plesiosaurs are known from sediments all over the world, ranging in age from the Hettangian (approximately 198 Myr) to the Turonian (approximately 92 Myr). However, due to a lack of detailed studies and because only incomplete specimens are usually reported, pliosaur evolution remains poorly understood. In this paper, we describe the three dimensionally preserved skull of the giant Jurassic pliosaur Rhomaleosaurus cramptoni. The first phylogenetic analysis dedicated to in-group relationships of pliosaurs allows us to hypothesise a number of well-supported lineages that correlate with marine biogeography and the palaeoecology of these reptiles. Rhomaleosaurids comprised a short-lived and early diverging lineage within pliosaurs, whose open-water top-predator niche was filled by other pliosaur taxa by the mid-late Jurassic.

  5. Surgical Treatment of an Immature Short-Rooted Traumatized Incisor with an Extensive Apical Lesion Using CEM Cement

    PubMed Central

    Asgary, Saeed; Fazlyab, Mahta

    2015-01-01

    Severe traumatic injuries to immature teeth often cause damage to periodontal ligament as well as dental pulp; pulp necrosis, root resorption and subsequent apical lesion are common consequences. This article reports the surgical management of an infected immature maxillary central incisor associated with a gigantic periradicular lesion and severe root resorption. The tooth had a history of trauma and the patient suffered from purulent sinus tract and tooth mobility. After unsuccessful multi-session disinfection with calcium hydroxide, root end surgery was planned. During flap surgery and lesion enucleation, the root end was cleaned and filled with calcium-enriched mixture (CEM) cement. After one year, the radiographic examination revealed that the lesion was almost completely replaced with newly formed bone. In addition, clinical examination showed favorable outcomes; the tooth was symptom-free and in function. Due to chemical, physical and biological properties of CEM cement, this biomaterial might be considered as the root-end filling material of choice. PMID:25834603

  6. Impact of Parallel Computing on Large Scale Aeroelastic Computations

    NASA Technical Reports Server (NTRS)

    Guruswamy, Guru P.; Kwak, Dochan (Technical Monitor)

    2000-01-01

    Aeroelasticity is computationally one of the most intensive fields in aerospace engineering. Though over the last three decades the computational speed of supercomputers have substantially increased, they are still inadequate for large scale aeroelastic computations using high fidelity flow and structural equations. In addition to reaching a saturation in computational speed because of changes in economics, computer manufactures are stopping the manufacturing of mainframe type supercomputers. This has led computational aeroelasticians to face the gigantic task of finding alternate approaches for fulfilling their needs. The alternate path to over come speed and availability limitations of mainframe type supercomputers is to use parallel computers. During this decade several different architectures have evolved. In FY92 the US Government started the High Performance Computing and Communication (HPCC) program. As a participant in this program NASA developed several parallel computational tools for aeroelastic applications. This talk describes the impact of those application tools on high fidelity based multidisciplinary analysis.

  7. 7. View of interior of Lock No. 2 on George ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. View of interior of Lock No. 2 on George washington 'Potowmack' Canal at Great Falls, Virginia. This lock is about 15 ft. in depth and possibly 70 or 60 ft. in length. Some 15 or 20 years ago, when a restoration was crudely attempted, the old oaken flooring, which was invariably placed at the bottom of canal locks, was roughly torn up and destroyed. The trunks and stumps of gigantic trees still remain from this restorative effort, and their girth indicates again the antiquity of this evidence of George Washington's work as an engineer. The stones are of the red Seneca type and were evidently ferried from the Maryland side above the dam and then brought by sled or rollers to this location. These stones were beautifully hand-cut and fitted with ... - Potowmack Company: Great Falls Canal, Lock No. 2, Great Falls, Fairfax County, VA

  8. Broadband giant-refractive-index material based on mesoscopic space-filling curves.

    PubMed

    Chang, Taeyong; Kim, Jong Uk; Kang, Seung Kyu; Kim, Hyowook; Kim, Do Kyung; Lee, Yong-Hee; Shin, Jonghwa

    2016-01-01

    The refractive index is the fundamental property of all optical materials and dictates Snell's law, propagation speed, wavelength, diffraction, energy density, absorption and emission of light in materials. Experimentally realized broadband refractive indices remain <40, even with intricately designed artificial media. Herein, we demonstrate a measured index >1,800 resulting from a mesoscopic crystal with a dielectric constant greater than three million. This gigantic enhancement effect originates from the space-filling curve concept from mathematics. The principle is inherently very broad band, the enhancement being nearly constant from zero up to the frequency of interest. This broadband giant-refractive-index medium promises not only enhanced resolution in imaging and raised fundamental absorption limits in solar energy devices, but also compact, power-efficient components for optical communication and increased performance in many other applications. PMID:27573337

  9. Lead in ancient Rome’s city waters

    PubMed Central

    Delile, Hugo; Blichert-Toft, Janne; Goiran, Jean-Philippe; Keay, Simon; Albarède, Francis

    2014-01-01

    It is now universally accepted that utilization of lead for domestic purposes and water distribution presents a major health hazard. The ancient Roman world was unaware of these risks. How far the gigantic network of lead pipes used in ancient Rome compromised public health in the city is unknown. Lead isotopes in sediments from the harbor of Imperial Rome register the presence of a strong anthropogenic component during the beginning of the Common Era and the Early Middle Ages. They demonstrate that the lead pipes of the water distribution system increased Pb contents in drinking water of the capital city by up to two orders of magnitude over the natural background. The Pb isotope record shows that the discontinuities in the pollution of the Tiber by lead are intimately entwined with the major issues affecting Late Antique Rome and its water distribution system. PMID:24753588

  10. Lead in ancient Rome's city waters.

    PubMed

    Delile, Hugo; Blichert-Toft, Janne; Goiran, Jean-Philippe; Keay, Simon; Albarède, Francis

    2014-05-01

    It is now universally accepted that utilization of lead for domestic purposes and water distribution presents a major health hazard. The ancient Roman world was unaware of these risks. How far the gigantic network of lead pipes used in ancient Rome compromised public health in the city is unknown. Lead isotopes in sediments from the harbor of Imperial Rome register the presence of a strong anthropogenic component during the beginning of the Common Era and the Early Middle Ages. They demonstrate that the lead pipes of the water distribution system increased Pb contents in drinking water of the capital city by up to two orders of magnitude over the natural background. The Pb isotope record shows that the discontinuities in the pollution of the Tiber by lead are intimately entwined with the major issues affecting Late Antique Rome and its water distribution system. PMID:24753588

  11. Control of Dzyaloshinskii-Moriya interaction in Mn(1-x)Fe(x)Ge: a first-principles study.

    PubMed

    Koretsune, Takashi; Nagaosa, Naoto; Arita, Ryotaro

    2015-01-01

    Motivated by the recent experiment on the size and helicity control of skyrmions in Mn(1-x)Fe(x)Ge, we study how the Dzyaloshinskii-Moriya (DM) interaction changes its size and sign in metallic helimagnets. By means of first-principles calculations, we successfully reproduce the non-trivial sign change of the DM interaction observed in the experiment. While the DM interaction sensitively depends on the carrier density or the detail of the electronic structure such as the size of the exchange splitting, its behavior can be systematically understood in terms of the distribution of anticrossing points in the band structure. By following this guiding principle, we can even induce gigantic anisotropy in the DM interaction by applying a strain to the system. These results pave the new way for skyrmion crystal engineering in metallic helimagnets. PMID:26304817

  12. On the fate of pumice rafts formed during the 2012 Havre submarine eruption.

    PubMed

    Jutzeler, Martin; Marsh, Robert; Carey, Rebecca J; White, James D L; Talling, Peter J; Karlstrom, Leif

    2014-01-01

    Pumice rafts are floating mobile accumulations of low-density pumice clasts generated by silicic volcanic eruptions. Pumice in rafts can drift for years, become waterlogged and sink, or become stranded on shorelines. Here we show that the pumice raft formed by the impressive, deep submarine eruption of the Havre caldera volcano (Southwest Pacific) in July 2012 can be mapped by satellite imagery augmented by sailing crew observations. Far from coastal interference, the eruption produced a single >400 km(2) raft in 1 day, thus initiating a gigantic, high-precision, natural experiment relevant to both modern and prehistoric oceanic surface dispersal dynamics. Observed raft dispersal can be accurately reproduced by simulating drift and dispersal patterns using currents from an eddy-resolving ocean model hindcast. For future eruptions that produce potentially hazardous pumice rafts, our technique allows real-time forecasts of dispersal routes, in addition to inference of ash/pumice deposit distribution in the deep ocean. PMID:24755668

  13. Macrodactyly with skin hypertrophy: a minimal form of the Proteus syndrome.

    PubMed

    Almeida, Hiram Larangeira de; Fiss, Roberto Coswig; Happle, Rudolf

    2011-01-01

    The Proteus syndrome was described 1983 . It has asymmetric gigantism of the limbs, verrucous epidermal naevi, cerebriform enlargement of the plantar region, vascular malformations and neoplasms, as lipomas. It received this denomination after Proteus from the Greek mythology, who had the ability to change his form . A 15 year-old boy, reported a congenital hypertrophy with syndactily of the second and third right fingers . The second case is a 35 year-old man, who reported that since birth the second right toe was bigger than the other toes, skin hypertrophy was also observed. These cases document a localized form if the Proteus syndrome, which may widen the spectrum of its variability. PMID:21738976

  14. Another Demo of the Unusual Thermal Properties of Rubber

    NASA Astrophysics Data System (ADS)

    Liff, Mark I.

    2010-10-01

    The unusual thermal behavior of rubbers, though discovered a long time ago, can still be mind-boggling for students and teachers who encounter this class of polymeric systems. Unlike other solids, stretched elastic polymers shrink upon heating. This is a manifestation of the Gough-Joule (G-J) effect.1-4 Joule in the 1850s studied the thermal behavior of rubbers that was initially explored by Gough in 1805. Properties of rubbers such as contraction upon heating, or the related phenomenon of heating upon fast expansion, did not make much sense at that time. Joule's work validated Gough's results, but the molecular basis of the unusual thermal behavior of rubbers remained unexplained for another 70 years. The physical ideas, taking into account gigantic conformational entropy of elastic polymers that explain their contraction on heating, were developed by Staudinger, Kuhn, and others only in the 1920s and 1930s.5

  15. Spider behaviors include oral sexual encounters.

    PubMed

    Gregorič, Matjaž; Šuen, Klavdija; Cheng, Ren-Chung; Kralj-Fišer, Simona; Kuntner, Matjaž

    2016-01-01

    Several clades of spiders whose females evolved giant sizes are known for extreme sexual behaviors such as sexual cannibalism, opportunistic mating, mate-binding, genital mutilation, plugging, and emasculation. However, these behaviors have only been tested in a handful of size dimorphic spiders. Here, we bring another lineage into the picture by reporting on sexual behavior of Darwin's bark spider, Caerostris darwini. This sexually size dimorphic Madagascan species is known for extreme web gigantism and for producing the world's toughest biomaterial. Our field and laboratory study uncovers a rich sexual repertoire that predictably involves cannibalism, genital mutilation, male preference for teneral females, and emasculation. Surprisingly, C. darwini males engage in oral sexual encounters, rarely reported outside mammals. Irrespective of female's age or mating status males salivate onto female genitalia pre-, during, and post-copulation. While its adaptive significance is elusive, oral sexual contact in spiders may signal male quality or reduce sperm competition. PMID:27126507

  16. Dynamics of the Earth's Inner Magnetosphere and Its Connection to the Ionosphere: Current Understanding and Challenges

    NASA Technical Reports Server (NTRS)

    Zheng, Yihua

    2011-01-01

    The Earth's inner magnetosphere, a vast volume in space spanning from 1.5 Re (Earth radii) to 10 Re, is a host to a variety of plasma populations (with energy from 1 eV to few MeV) and physical processes where most of which involve plasma and field coupling. As a gigantic particle accelerator, the inner magnetosphere includes three overlapping regions: the plasmasphere, the ring current, and the Van Allen radiation belt. The complex structures and dynamics of these regions are externally driven by solar activities and internally modulated by intricate interactions and coupling. As a major constituent of Space Weather, the inner magnetosphere is both scientifically intriguing and practically important to our society. In this presentation, I will discuss our recent results from the Comprehensive Ring Current Model, in the context of our current understanding of the inner magnetosphere in general and challenges ahead in making further progresses.

  17. Dynamics of the Earth's Inner Magnetosphere and its Connection to the Ionosphere: Current Understanding and Challenges

    NASA Technical Reports Server (NTRS)

    Zheng, Yihua

    2010-01-01

    The Earth's inner magnetosphere, a vast volume in space spanning from 1.5 Re (Earth radii) to 10 Re, is a host to a variety of plasma populations (with energy from 1 eV to few MeV) and physical processes where most of which involve plasma and field coupling. As a gigantic particle accelerator, the inner magnetosphere includes three overlapping regions: the plasmasphere, the ring current, and the Van Allen radiation belt. The complex structures and dynamics of these regions are externally driven by solar activities and internally modulated by intricate interactions and coupling. As a major constituent of Space Weather, the inner magnetosphere is both scientifically intriguing and practically important to our society. In this presentation, I will discuss our recent results from the Comprehensive Ring Current Model, in the context of our current understanding of the inner magnetosphere in general and challenges ahead in making further progresses.

  18. Total Hip Arthroplasty Using a Polished Tapered Cemented Stem in Hereditary Multiple Exostosis.

    PubMed

    Kanda, Akio; Kaneko, Kazuo; Obayashi, Osamu; Mogami, Atsuhiko

    2016-01-01

    A 61-year-old Japanese man underwent right total hip arthroplasty for hereditary multiple exostosis. At first presentation, he had suffered from coxalgia for a long time. On radiographic images, there was a gigantic femoral head, increased shaft angle, and large diameter of the femoral neck. He had also developed coxarthrosis and severe pain of the hip joint. The transformation of the proximal femur bone causes difficulty in setting a cementless total hip prosthesis. Therefore, total hip arthroplasty using a cemented polished tapered stem was performed via a direct lateral approach. Using a cemented polished tapered stem allowed us to deal with the femoral bone transformation and bone substance defectiveness due to exostosis and also minimized the invasiveness of the operation. PMID:27127668

  19. Size-, electric-field-, and frequency-dependent third-order nonlinear optical properties of hydrogenated silicon nanoclusters

    PubMed Central

    Li, Haipeng; Xu, Hu; Shen, Xiaopeng; Han, Kui; Bi, Zetong; Xu, Runfeng

    2016-01-01

    We investigated the electronic properties and second hyperpolarizabilities of hydrogenated silicon nanoclusters (H-SiNCs) by using the density functional theory method. The effects of cluster size, external electric field and incident frequency on the second hyperpolarizability were also examined, respectively. We found that small H-SiNCs exhibit large second hyperpolarizability. With the increase of the number of silicon atoms in H-SiNCs, the frontier molecular orbital energy gap decreases, attributed to the enhancement of the second hyperpolarizability. Interestingly, we also found the electric-field-induced gigantic enhancement of the second hyperpolarizability for H-SiNCs due to the change of electron density distributions. In addition, our results demonstrate a significant dependence on the frequency of incident light. PMID:27305957

  20. Size-, electric-field-, and frequency-dependent third-order nonlinear optical properties of hydrogenated silicon nanoclusters.

    PubMed

    Li, Haipeng; Xu, Hu; Shen, Xiaopeng; Han, Kui; Bi, Zetong; Xu, Runfeng

    2016-01-01

    We investigated the electronic properties and second hyperpolarizabilities of hydrogenated silicon nanoclusters (H-SiNCs) by using the density functional theory method. The effects of cluster size, external electric field and incident frequency on the second hyperpolarizability were also examined, respectively. We found that small H-SiNCs exhibit large second hyperpolarizability. With the increase of the number of silicon atoms in H-SiNCs, the frontier molecular orbital energy gap decreases, attributed to the enhancement of the second hyperpolarizability. Interestingly, we also found the electric-field-induced gigantic enhancement of the second hyperpolarizability for H-SiNCs due to the change of electron density distributions. In addition, our results demonstrate a significant dependence on the frequency of incident light. PMID:27305957

  1. The influence of imitated microgravity on the amyloplast structure, the composition and characteristics of potato minituber

    NASA Astrophysics Data System (ADS)

    Nedukha, O. M.; Kordyum, Ye. L.; Schnyukova, Ye. I.

    The influence of imitated microgravity (clinorotation, 2 rev/min) of long-term duration on the structural-functional organization of Solanum tuberosum L. (cv Adreta) minituber cells is studied. An essential influence on 45-day minituber size, on the content and composition of starch, on the solubility of starch in water and on the structure of amyloplasts in the storage parenchyma of potato minitubers is detected. The appearance of a fraction of "gigantic" amyloplasts in starch-storage parenchyma is observed during horizontal clinorotation of long-term duration. The correlation between the decrease of content amylose and the inhibition of starch solubility in water is detected under long-term clinorotation. The results point to some changes of the carbohydrate metabolism of potato storage organs under the effect of microgravity imitation.

  2. The aerodynamics of Argentavis, the world's largest flying bird from the Miocene of Argentina

    PubMed Central

    Chatterjee, Sankar; Templin, R. Jack; Campbell, Kenneth E.

    2007-01-01

    We calculate the flight performance of the gigantic volant bird Argentavis magnificens from the upper Miocene (≈6 million years ago) of Argentina using a computer simulation model. Argentavis was probably too large (mass ≈70 kg) to be capable of continuous flapping flight or standing takeoff under its own muscle power. Like extant condors and vultures, Argentavis would have extracted energy from the atmosphere for flight, relying on thermals present on the Argentinean pampas to provide power for soaring, and it probably used slope soaring over the windward slopes of the Andes. It was an excellent glider, with a gliding angle close to 3° and a cruising speed of 67 kph. Argentavis could take off by running downhill, or by launching from a perch to pick up flight speed. Other means of takeoff remain problematic. PMID:17609382

  3. Coronal Mass Ejections: From Sun to Earth

    NASA Astrophysics Data System (ADS)

    Patsourakos, S.

    2016-06-01

    Coronal Mass Ejections (CMEs) are gigantic expulsions of magnetized plasmas from the solar corona into the interplanetary (IP) space. CMEs spawn ~ 1015 gr of mass and reach speeds ranging between several hundred to a few thousand km/s (e.g., Gopalswamy et al. 2009; Vourlidas et al. 2010). It takes 1-5 days for a CME to reach Earth. CMEs are one of the most energetic eruptive manifestations in the solar system and are major drivers of space weather via their magnetic fields and energetic particles, which are accelerated by CME-driven shocks. In this review we give a short account of recent, mainly observational, results on CMEs from the STEREO and SDO missions which include the nature of their pre-eruptive and eruptive configurations and the CME propagation from Sun to Earth. We conclude with a discussion of the exciting capabilities in CME studies that will soon become available from new solar and heliospheric instrumentation.

  4. Mass extinctions and cosmic collisions - A lunar test

    NASA Astrophysics Data System (ADS)

    Horz, F.

    The possibility has been considered that some or all major mass extinctions in the geologic record of earth are caused by the collision of massive, cosmic objects. Thus, it has been proposed that the unusual concentration of siderophile elements in strata at which the boundary between the Cretaceous (K) and Tertiary (T) geologic time periods has been placed must represent the remnants of a gigantic meteorite. However, a large 65-m.y.-old crater which could have been the result of the impact of this meteorite is not presently known on earth. One approach to evaluate the merits of the collisional hypothesis considered is based on the study of the probability of collision between a cosmic object of a suitable size and the earth. As moon and earth were subject to the same bombardment history and the preservation of craters on the moon is much better than on earth, a consideration of the lunar cratering record may provide crucial information.

  5. Isotope Fractionation and Atmospheric Oxygen: Implications for Phanerozoic O2 Evolution

    NASA Astrophysics Data System (ADS)

    Berner, R. A.; Petsch, S. T.; Lake, J. A.; Beerling, D. J.; Popp, B. N.; Lane, R. S.; Laws, E. A.; Westley, M. B.; Cassar, N.; Woodward, F. I.; Quick, W. P.

    2000-03-01

    Models describing the evolution of the partial pressure of atmospheric oxygen over Phanerozoic time are constrained by the mass balances required between the inputs and outputs of carbon and sulfur to the oceans. This constraint has limited the applicability of proposed negative feedback mechanisms for maintaining levels of atmospheric O2 at biologically permissable levels. Here we describe a modeling approach that incorporates O2-dependent carbon and sulfur isotope fractionation using data obtained from laboratory experiments on carbon-13 discrimination by vascular land plants and marine plankton. The model allows us to calculate a Phanerozoic O2 history that agrees with independent models and with biological and physical constraints and supports the hypothesis of a high atmospheric O2 content during the Carboniferous (300 million years ago), a time when insect gigantism was widespread.

  6. Wildland fires and nuclear winters. Selected reconstruction of historic large fires. Technical report, 1 March 1985-28 February 1986

    SciTech Connect

    Pyne, S.J.; Omi, P.N.

    1986-02-28

    Under the nuclear winter scenario, large wildland fires are expected to contribute to a general smoke plume and are considered potential analogues for the behavior of gigantic palls. As a means of testing the reasonableness of current estimates of a wildland fire contribution, the authors reconstructed from the historic record two major events; the Tillamook Burn of August 1933 and the 1910 fire complex in the Northern Rocky Mountains. Both events are near the upper limit for wildland fires - the Tillamook Burn for a single fire. For the 1910 fires, for which environmental data are skimpy, a modern analogue, the Sundance fire (1967), was used for certain extrapolations. Reconstructed fire behavior and estimated smoke production suggest that current nuclear winter models overestimate the magnitude of a wildland component.

  7. Spider behaviors include oral sexual encounters

    PubMed Central

    Gregorič, Matjaž; Šuen, Klavdija; Cheng, Ren-Chung; Kralj-Fišer, Simona; Kuntner, Matjaž

    2016-01-01

    Several clades of spiders whose females evolved giant sizes are known for extreme sexual behaviors such as sexual cannibalism, opportunistic mating, mate-binding, genital mutilation, plugging, and emasculation. However, these behaviors have only been tested in a handful of size dimorphic spiders. Here, we bring another lineage into the picture by reporting on sexual behavior of Darwin’s bark spider, Caerostris darwini. This sexually size dimorphic Madagascan species is known for extreme web gigantism and for producing the world’s toughest biomaterial. Our field and laboratory study uncovers a rich sexual repertoire that predictably involves cannibalism, genital mutilation, male preference for teneral females, and emasculation. Surprisingly, C. darwini males engage in oral sexual encounters, rarely reported outside mammals. Irrespective of female’s age or mating status males salivate onto female genitalia pre-, during, and post-copulation. While its adaptive significance is elusive, oral sexual contact in spiders may signal male quality or reduce sperm competition. PMID:27126507

  8. Dramatic growth of mice that develop from eggs microinjected with metallothionein–growth hormone fusion genes

    PubMed Central

    Palmiter, Richard D.; Brinster, Ralph L.; Hammer, Robert E.; Trumbauer, Myrna E.; Rosenfeld, Michael G.; Birnberg, Neal C.; Evans, Ronald M.

    2016-01-01

    A DNA fragment containing the promoter of the mouse metallothionein-I gene fused to the structural gene of rat growth hormone was microinjected into the pronuclei of fertilized mouse eggs. Of 21 mice that developed from these eggs, seven carried the fusion gene and six of these grew significantly larger than their littermates. Several of these transgenic mice had extraordinarily high levels of the fusion mRNA in their liver and growth hormone in their serum. This approach has implications for studying the biological effects of growth hormone, as a way to accelerate animal growth, as a model for gigantism, as a means of correcting genetic disease, and as a method of farming valuable gene products. PMID:6958982

  9. Ancient drainage basin of the Tharsis region, Mars: Potential source for outflow channel systems and putative oceans or paleolakes

    USGS Publications Warehouse

    Dohm, J.M.; Ferris, J.C.; Baker, V.R.; Anderson, R.C.; Hare, T.M.; Strom, R.G.; Barlow, N.G.; Tanaka, K.L.; Klemaszewski, J.E.; Scott, D.H.

    2001-01-01

    Paleotopographic reconstructions based on a synthesis of published geologic information and high-resolution topography, including topographic profiles, reveal the potential existence of an enormous drainage basin/aquifer system in the eastern part of the Tharsis region during the Noachian Period. Large topographic highs formed the margin of the gigantic drainage basin. Subsequently, lavas, sediments, and volatiles partly infilled the basin, resulting in an enormous and productive regional aquifer. The stacked sequences of water-bearing strata were then deformed locally and, in places, exposed by magmatic-driven uplifts, tectonic deformation, and erosion. This basin model provides a potential source of water necessary to carve the large outflow channel systems of the Tharsis and surrounding regions and to contribute to the formation of putative northern-plains ocean(s) and/or paleolakes. Copyright 2001 by the American Geophysical Union.

  10. Captura de galaxias enanas en cúmulos de galaxias

    NASA Astrophysics Data System (ADS)

    Bassino, L. P.; Muzzio, J. C.; Pérez, J.

    Se investiga el proceso de captura de galaxias enanas por parte de galaxias gigantes, en presencia de un campo externo causado por materia distribuída y otras galaxias pertenecientes al cúmulo en que se produce el fenómeno. Se trabaja mediante simulaciones numéricas, generando condiciones iniciales típicas de cúmulos de galaxias y representando, con un espectro de masas, a las galaxias más masivas y, como partículas de prueba, a las enanas. Se sigue la evolución del sistema empleando un código de integración de N-cuerpos y se analizan los resultados para determinar las capturas de galaxias enanas.

  11. Comparative 3D analyses and palaeoecology of giant early amphibians (Temnospondyli: Stereospondyli).

    PubMed

    Fortuny, Josep; Marcé-Nogué, Jordi; Steyer, J-Sébastien; de Esteban-Trivigno, Soledad; Mujal, Eudald; Gil, Lluís

    2016-01-01

    Macroevolutionary, palaeoecological and biomechanical analyses in deep time offer the possibility to decipher the structural constraints, ecomorphological patterns and evolutionary history of extinct groups. Here, 3D comparative biomechanical analyses of the extinct giant early amphibian group of stereospondyls together with living lissamphibians and crocodiles, shows that: i) stereospondyls had peculiar palaeoecological niches with proper bites and stress patterns very different than those of giant salamanders and crocodiles; ii) their extinction may be correlated with the appearance of neosuchians, which display morphofunctional innovations. Stereospondyls weathered the end-Permian mass extinction, re-radiated, acquired gigantic sizes and dominated (semi) aquatic ecosystems during the Triassic. Because these ecosystems are today occupied by crocodilians, and stereospondyls are extinct amphibians, their palaeobiology is a matter of an intensive debate: stereospondyls were a priori compared with putative living analogous such as giant salamanders and/or crocodilians and our new results try to close this debate. PMID:27457883

  12. Slow and Steady: Ocean Circulation. The Influence of Sea Surface Height on Ocean Currents

    NASA Technical Reports Server (NTRS)

    Haekkinen, Sirpa

    2000-01-01

    The study of ocean circulation is vital to understanding how our climate works. The movement of the ocean is closely linked to the progression of atmospheric motion. Winds close to sea level add momentum to ocean surface currents. At the same time, heat that is stored and transported by the ocean warms the atmosphere above and alters air pressure distribution. Therefore, any attempt to model climate variation accurately must include reliable calculations of ocean circulation. Unlike movement of the atmosphere, movement of the ocean's waters takes place mostly near the surface. The major patterns of surface circulation form gigantic circular cells known as gyres. They are categorized according to their general location-equatorial, subtropical, subpolar, and polar-and may run across an entire ocean. The smaller-scale cell of ocean circulation is known' as an eddy. Eddies are much more common than gyres and much more difficult to track in computer simulations of ocean currents.

  13. The intersection of urban planning, art, and public health: the Sunnyside Piazza.

    PubMed

    Semenza, Jan C

    2003-09-01

    Deteriorating physical features of urban environments can negatively influence public health. Dilapidated environments and urban blight tend to promote alienation and can be associated with social disorder, vandalism, crime, drug abuse, traffic violations, and littering, which in turn affects health and well-being. In the late 1990s, the Sunnyside neighborhood in Portland, Ore, was plagued by many of these problems. In an attempt to invigorate neighborhood stewardship, the community organized and created a public gathering place; together, they painted a gigantic sunflower in the middle of an intersection and installed several interactive art features. As a result of these collective actions of "place-making," social capital has increased, thus revitalizing the community, and expanded social networks among residents have stimulated a sense of well-being. PMID:12948959

  14. FASTBUS in Europe, status and plans

    SciTech Connect

    Verweij, H.

    1984-02-01

    FASTBUS activity in Europe has definitely taken the direction of implementation and application. At SIN a system has successfully been commissioned and at CERN a multicrate configuration is being prepared for 1984. The importance of a single common data acquisition standard having been recognized for LEP experiments the data acquisition systems in preparation for these gigantic collaborations are largely to be based on FASTBUS. Starter kits have been composed for the various collaborating groups and laboratories while the first commercially produced modules have become available. The ESONE-ASSG has continued its coordinating role and, having published a European version of the FASTBUS specification, is now actively engaged in compiling supplementary information in documentary form for engineers, programmers and users.

  15. Bilateral Renal Dysplasia, Nephroblastomatosis, and Bronchial Stenosis. A New Syndrome?

    PubMed Central

    Rodriguez, Maria Matilde; Correa-Medina, Mayrin; Whittington, Elizabeth E.

    2015-01-01

    Bilateral nephroblastomatosis (NB) is an uncommon renal anomaly characterized by multiple confluent nephrogenic rests scattered through both kidneys, with only a limited number of cases reported in the medical literature. Some of these children may have associated either Perlman or Beckwith–Wiedemann syndrome and others do not demonstrate syndromic features. We report a full-term boy with anteverted nose, bilateral bronchial stenosis due to lack of cartilage, bilateral obstructive renal dysplasia and NB with glomeruloid features. The infant had visceromegaly, but neither gigantism nor hemihypertrophy. Immunohistochemistry for PAX2 (Paired box gene-2) and WT-1 (Wilms Tumor 1) were strongly positive in the areas of NB. GLEPP-1 (Glomerular Epithelial Protein) did not stain the areas of NB with a glomeruloid appearance, but was positive in the renal glomeruli as expected. We found neither associated bronchial stenosis nor the histology of NB resembling giant glomeruli in any of the reported cases of NB. PMID:25871299

  16. Mainland size variation informs predictive models of exceptional insular body size change in rodents

    PubMed Central

    Durst, Paul A. P.; Roth, V. Louise

    2015-01-01

    The tendency for island populations of mammalian taxa to diverge in body size from their mainland counterparts consistently in particular directions is both impressive for its regularity and, especially among rodents, troublesome for its exceptions. However, previous studies have largely ignored mainland body size variation, treating size differences of any magnitude as equally noteworthy. Here, we use distributions of mainland population body sizes to identify island populations as ‘extremely’ big or small, and we compare traits of extreme populations and their islands with those of island populations more typical in body size. We find that although insular rodents vary in the directions of body size change, ‘extreme’ populations tend towards gigantism. With classification tree methods, we develop a predictive model, which points to resource limitations as major drivers in the few cases of insular dwarfism. Highly successful in classifying our dataset, our model also successfully predicts change in untested cases. PMID:26085585

  17. Cloud Formation and Water Transport on Mars after Major Outflow Events

    NASA Technical Reports Server (NTRS)

    Santiago, D. L.; Colaprete, A.; Kreslavsky, M.; Kahre, M. A.; Asphaug, E.

    2012-01-01

    The triggering of a robust water cycle on Mars might have been caused by the gigantic flooding events evidenced by outflow channels. We use the Ames Mars General Circulation Model (MGCM) to test this hypothesis, studying how these presumably abrupt eruptions of water might have affected the climate of Mars in the past. We model where the water ultimately went as part of a transient atmospheric water cycle, to answer questions including: (1) Can sudden introductions of large amounts of water on the Martian surface lead to a new equilibrated water cycle? (2) What are the roles of water vapor and water ice clouds to sudden changes in the water cycle on Mars? (3) How are radiative feedbacks involved with this? (4) What is the ultimate fate of the outflow water? (5) Can we tie certain geological features to outflow water redistributed by the atmosphere?

  18. Many monstrous Missoula floods down channeled scabland and Columbia Valley, Washington

    USGS Publications Warehouse

    Waitt, Richard B.; Denlinger, Roger P.; O'Connor, Jim

    2009-01-01

    The late Wisconsin Missoula floods are Earth's largest known discharges of fresh water. They carved Washington's Channeled Scabland--made famous by J H. Bretz's writings in the 1920s to 1950s--and deposited sporadic huge gravel bars in the Scab-lands and Columbia valley. Since the late 1970s the great floods have been shown to number several score and to have been released as gigantic jökulhlaups. This five-day fieldtrip zig-zags broadly along and across the Scablands and down Columbia valley, viewing much geomorphic and stratigraphic evidence of the Missoula floods, at the end washing into Portland and Geological Society of America's 2009 Annual Meeting.

  19. Crystal structure of Streptococcus pneumoniae pneumolysin provides key insights into early steps of pore formation.

    PubMed

    Lawrence, Sara L; Feil, Susanne C; Morton, Craig J; Farrand, Allison J; Mulhern, Terrence D; Gorman, Michael A; Wade, Kristin R; Tweten, Rodney K; Parker, Michael W

    2015-01-01

    Pore-forming proteins are weapons often used by bacterial pathogens to breach the membrane barrier of target cells. Despite their critical role in infection important structural aspects of the mechanism of how these proteins assemble into pores remain unknown. Streptococcus pneumoniae is the world's leading cause of pneumonia, meningitis, bacteremia and otitis media. Pneumolysin (PLY) is a major virulence factor of S. pneumoniae and a target for both small molecule drug development and vaccines. PLY is a member of the cholesterol-dependent cytolysins (CDCs), a family of pore-forming toxins that form gigantic pores in cell membranes. Here we present the structure of PLY determined by X-ray crystallography and, in solution, by small-angle X-ray scattering. The crystal structure reveals PLY assembles as a linear oligomer that provides key structural insights into the poorly understood early monomer-monomer interactions of CDCs at the membrane surface. PMID:26403197

  20. Visualization of the Internal Structure of Volcanoes with Cosmic-ray Muons

    NASA Astrophysics Data System (ADS)

    Tanaka, Hiroyuki K. M.

    2016-09-01

    High-energy muons that are produced via the reaction between primary cosmic rays and the Earth's atmosphere can be used as a radiographic probe to explore the density distribution in gigantic objects including shallow parts of a volcano's interior. This new subterranean imaging technique is called muography. So far, muographic results have been acquired from eight volcanoes around the world as well as various targets including limestone caves, fault zones, industrial plants, and historical ruins. Taking all of the observational data together, it appears that muography can serve as a new and alternative high-resolution imaging technique, providing a fresh approach to Earth studies. This review describes observational studies in which muography has been used to explore the Earth's interior. Particular attention is paid to muography of magma convection and pathways in volcanoes around the world. The results are summarized here, and an outlook regarding anticipated future observations is briefly discussed.

  1. Direct Determination of 3D Distribution of Elemental Composition in Single Semiconductor Nanoislands by Scanning Auger Microscopy

    NASA Astrophysics Data System (ADS)

    Ponomaryov, Semyon S.; Yukhymchuk, Volodymyr O.; Lytvyn, Peter M.; Valakh, Mykhailo Ya

    2016-02-01

    An application of scanning Auger microscopy with ion etching technique and effective compensation of thermal drift of the surface analyzed area is proposed for direct local study of composition distribution in the bulk of single nanoislands. For GexSi1 - x-nanoislands obtained by MBE of Ge on Si-substrate gigantic interdiffusion mixing takes place both in the open and capped nanostructures. Lateral distributions of the elemental composition as well as concentration-depth profiles were recorded. 3D distribution of the elemental composition in the d-cluster bulk was obtained using the interpolation approach by lateral composition distributions in its several cross sections and concentration-depth profile. It was shown that there is a germanium core in the nanoislands of both nanostructure types, which even penetrates the substrate. In studied nanostructures maximal Ge content in the nanoislands may reach about 40 at.%.

  2. Bone deformities and skeletal malformations in the Roman Imperial Age.

    PubMed

    Minozzi, Simona; Catalano, Paola; Pantano, Walter; Caldarini, Carla; Fornaciari, Gino

    2014-01-01

    This paper describes some cases of individuals affected by skeletal deformities resulting in "freak" appearance. The skeletal remains were found during large archaeological excavations in the Roman territory, carried out by the Special Superintendence to the Archeological Heritage of Rome in the last years, dated back to the Imperial Age. The first cases reported are referred to two growth disorders with opposite effects: a case of dwarfism and another of gigantism. The former concerns a young man from the Collatina necropolis with very short and malformed limbs, which allowed a diagnosis of acondroplasic dwarfism, a rare congenital disorder that limits height below 130 cm. The latter case comes from the necropolis of Torre Serpentana in Fidenae, and is instead referred to a young person of very high stature, about 204 cm, suffering from Gigantism, a rare condition which in this case seems to have been linked to a hormonal dysfunction due to a pituitary adenoma. A third case regards a joint disease affecting the vertebral column and causing severe deformities. The skeleton was found in the Collatina necropolis and belongs to an old woman, suffering from ankylosing spondylitis. Finally, the last and very peculiar case is related to an individual recovered in the necropolis of Castel Malnome. The skeletal remains belong to an adult man with a complete fusion of the temporo-mandibular joint, which compromised mastication and caused severe deformation of the maxillofacial complex. These cases are described in detail together with the possible implications that these deformities could have on in the social context. PMID:25702379

  3. Measuring the vertical electrical field above an oceanic convection system using a meteorological sounding balloon

    NASA Astrophysics Data System (ADS)

    Chen, A. B.; Chiu, C.; Lai, S.; Chen, C.; Kuo, C.; Su, H.; Hsu, R.

    2012-12-01

    The vertical electric field above thundercloud plays an important role in the generation and modeling of transient luminous events. For example, Pasko [1995] proposed that the high quasi-static E-field following the positive cloud-to-ground lightning could accelerate and input energy to ambient electrons; as they collide and excite nitrogen and oxygen molecules in upper atmosphere, sprites may be induced. A series of balloon experiments led by Holzworth have investigated the temporal and spatial fluctuations of the electric field and conductivity in the upper atmosphere at different sites [Holzworth 2005, and references in]. But the strength and variation of the vertical electric field above thundercloud, especially oceanic ones, are not well documented so far. A lightweight, low-cost measurement system including an electric field meter and the associated aviation electronics are developed to carry out the in-situ measurement of the vertical electric field and the inter-cloud charge distribution. Our measuring system was first deployed using a meteorological sounding balloon from Taitung, Taiwan in May 2012. The measured electric field below 3km height shows an exponential decay and it is consistent with the expected potential gradient variation between ionosphere and the Earth surface. But the background strength of the measured E-field grows up exponentially and a violent fluctuations is also observed when the balloon flew over a developing oceanic convection cell. The preliminary results from this flight will be reported and discussed. This low-cost electric field meter is developed within one year. In the coming months, more flights will be performed with the aim to measure the rapid variation of the electric field above thundercloud as well as the E-field that may induce transient luminous events. Our ground campaigns show that the occurrence rates of blue and gigantic jet are relatively high in the vicinity of Taiwan. Our experiment can be used to diagnose

  4. Global distributions and occurrence rates of transient luminous events

    NASA Astrophysics Data System (ADS)

    Chen, Alfred B.; Kuo, Cheng-Ling; Lee, Yi-Jen; Su, Han-Tzong; Hsu, Rue-Ron; Chern, Jyh-Long; Frey, Harald U.; Mende, Stephen B.; Takahashi, Yukihiro; Fukunishi, Hiroshi; Chang, Yeou-Shin; Liu, Tie-Yue; Lee, Lou-Chuang

    2008-08-01

    We report the global transient luminous event (TLE) distributions and rates based on the Imager of Sprites and Upper Atmospheric Lightning (ISUAL) experiment onboard the FORMOSAT-2 satellite. ISUAL observations cover 45°S to 25°N latitude during the northern summer and 25°S to 45°N latitude during the northern winter. From July 2004 to June 2007, ISUAL recorded 5,434 elves, 633 sprites, 657 halos, and 13 gigantic jets. Surprisingly, elve is the dominant type of TLEs, while sprites/halos are a distant second. Elve occurrence rate jumps as the sea surface temperature exceeds 26 degrees Celsius, manifesting an ocean-atmosphere-ionosphere coupling. In the ISUAL survey, elves concentrate over the Caribbean Sea, South China Sea, east Indian Ocean, central Pacific Ocean, west Atlantic Ocean, and southwest Pacific Ocean; while sprites congregate over central Africa, Japan Sea, and west Atlantic Ocean. The ISUAL experiment observed global rates of 3.23, 0.50, 0.39, and 0.01 events per minute for elves, sprites, halos, and gigantic jets, respectively. Taking the instrumental detection sensitivity and the restricted survey area into account, the corrected global occurrence rates for sprites and elves likely are a factor of two and an order of magnitude higher, respectively. ISUAL observations also indicate that the relative frequency of high peak current lightning (>80 kA) is 10 times higher over the oceans than over the land. On the basis of the corrected ISUAL elve global occurrence rate, the total electron content at the lower ionosphere above elve hot zones was computed to be elevated by more than 5%.

  5. Mild pituitary phenotype in 3- and 12-month-old Aip-deficient male mice.

    PubMed

    Lecoq, Anne-Lise; Zizzari, Philippe; Hage, Mirella; Decourtye, Lyvianne; Adam, Clovis; Viengchareun, Say; Veldhuis, Johannes D; Geoffroy, Valérie; Lombès, Marc; Tolle, Virginie; Guillou, Anne; Karhu, Auli; Kappeler, Laurent; Chanson, Philippe; Kamenický, Peter

    2016-10-01

    Germline mutations in the aryl hydrocarbon receptor-interacting protein (AIP) gene predispose humans to pituitary adenomas, particularly of the somatotroph lineage. Mice with global heterozygous inactivation of Aip (Aip(+/-)) also develop pituitary adenomas but differ from AIP-mutated patients by the high penetrance of pituitary disease. The endocrine phenotype of these mice is unknown. The aim of this study was to determine the endocrine phenotype of Aip(+/-) mice by assessing the somatic growth, ultradian pattern of GH secretion and IGF1 concentrations of longitudinally followed male mice at 3 and 12 months of age. As the early stages of pituitary tumorigenesis are controversial, we also studied the pituitary histology and somatotroph cell proliferation in these mice. Aip(+/-) mice did not develop gigantism but exhibited a leaner phenotype than wild-type mice. Analysis of GH pulsatility by deconvolution in 12-month-old Aip(+/-) mice showed a mild increase in total GH secretion, a conserved GH pulsatility pattern, but a normal IGF1 concentration. No pituitary adenomas were detected up to 12 months of age. An increased ex vivo response to GHRH of pituitary explants from 3-month-old Aip(+/-) mice, together with areas of enlarged acini identified on reticulin staining in the pituitary of some Aip(+/-) mice, was suggestive of somatotroph hyperplasia. Global heterozygous Aip deficiency in mice is accompanied by subtle increase in GH secretion, which does not result in gigantism. The absence of pituitary adenomas in 12-month-old Aip(+/-) mice in our experimental conditions demonstrates the important phenotypic variability of this congenic mouse model. PMID:27621108

  6. Genotypic variation in host response to infection affects parasite reproductive rate.

    PubMed

    Tavalire, Hannah F; Blouin, Michael S; Steinauer, Michelle L

    2016-02-01

    Parasite fitness is largely influenced by a variation in host response due to the host's genetic background. Here we investigated the impact of host genotype on pathogen success in the snail vector of its castrating parasite, Schistosoma mansoni. We infected five inbred lines of Biomphalaria glabrata with two infection doses and followed their growth, reproductive output and parasite production throughout the course of infection. There was no difference in resistance to infection among inbred lines, but lines varied in their responses to infection and the numbers of parasites produced. Snails did not compensate for castration by increasing their fecundity during the early phase of infection (fecundity compensation). However, some lines were able to delay parasite shedding for up to 30 weeks, thus prolonging reproduction before the onset of castration. Here we propose this strategy as a novel defense against castrating pathogens in snails. Gigantism, a predicted outcome of castration due to energy reallocation, occurred early in infection (<15 weeks) and was not universal among the snail lines. Lines that did not show gigantism were also characterised by a high parasite production rate and low survivorship, perhaps indicating energy reallocation into parasite production and costly immune defense. We observed no differences in total parasite production among lines throughout the entire course of infection, although lines differed in their parasite reproductive rate. The average rate of parasite production varied among lines from 1300 to 2450 cercariae within a single 2h shedding period, resulting in a total production of 6981-29,509 cercariae over the lifetime of a single snail. Regardless of genetic background, snail size was a strong predictor of parasite reproduction: each millimetre increase in snail size at the time of the first shed resulted in up to 3500 more cercariae over the lifetime of the snail. The results of this study provide a detailed picture of

  7. The origins of the giant pill-millipedes from Madagascar (Diplopoda: Sphaerotheriida: Arthrosphaeridae).

    PubMed

    Wesener, Thomas; Raupach, Michael J; Sierwald, Petra

    2010-12-01

    Giant pill-millipedes (order Sphaerotheriida) are large-bodied millipedes without poison glands which can roll-up into a complete ball. Their disconnected area of distribution spanning South Africa, Madagascar, India, SE Asia, Australia and New Zealand makes them interesting model organisms for biogeographic studies. The here presented phylogeny is based on a molecular dataset covering all areas of distribution with a special focus on Madagascar, where some species of giant pill-millipedes show island gigantism, reaching the size of a baseball. For our study, two mitochondrial genes (partial 16S rRNA and COI) as well as the complete nuclear 18S rDNA were sequenced. While many recent vertebrate studies hint that the ancestors of the recent Malagasy fauna crossed the >350 km wide Mozambique Channel several times, no such crossing was discovered in the Sphaerotheriida. For the first time in a molecular phylogenetic study of soil arthropods, a Madagascar-India group, the family Arthrosphaeridae, is recovered, hinting to a Gondwanan origin of the Sphaerotheriida. The Malagasy-Indian family Arthrosphaeridae forms a monophyletic, statistically well-supported group in all obtained trees. The giant pill-millipedes from Madagascar are paraphyletic because the Malagasy genus Sphaeromimus is the sister-taxon of the Indian Arthrosphaera. In Sphaeromimus, an ecotone shift occurred only once: the spiny forest species Sphaeromimus musicus forms the sister-clade to the species collected in rainforests and littoral rainforests. The two species of the Malagasy genus Zoosphaerium which express island gigantism form a monophyletic group in some trees, but these trees lack good statistical support. Deeper nodes inside the Sphaerotheriida, like the position of the Australian genera Procyliosoma and Epicyliosoma, the Southeast Asian family Zephroniidae and the South African genus Sphaerotherium could not be resolved. This study is the first genetic study inside the order Sphaerotheriida

  8. X-linked acrogigantism syndrome: clinical profile and therapeutic responses.

    PubMed

    Beckers, Albert; Lodish, Maya Beth; Trivellin, Giampaolo; Rostomyan, Liliya; Lee, Misu; Faucz, Fabio R; Yuan, Bo; Choong, Catherine S; Caberg, Jean-Hubert; Verrua, Elisa; Naves, Luciana Ansaneli; Cheetham, Tim D; Young, Jacques; Lysy, Philippe A; Petrossians, Patrick; Cotterill, Andrew; Shah, Nalini Samir; Metzger, Daniel; Castermans, Emilie; Ambrosio, Maria Rosaria; Villa, Chiara; Strebkova, Natalia; Mazerkina, Nadia; Gaillard, Stéphan; Barra, Gustavo Barcelos; Casulari, Luis Augusto; Neggers, Sebastian J; Salvatori, Roberto; Jaffrain-Rea, Marie-Lise; Zacharin, Margaret; Santamaria, Beatriz Lecumberri; Zacharieva, Sabina; Lim, Ee Mun; Mantovani, Giovanna; Zatelli, Maria Chaira; Collins, Michael T; Bonneville, Jean-François; Quezado, Martha; Chittiboina, Prashant; Oldfield, Edward H; Bours, Vincent; Liu, Pengfei; W de Herder, Wouter; Pellegata, Natalia; Lupski, James R; Daly, Adrian F; Stratakis, Constantine A

    2015-06-01

    X-linked acrogigantism (X-LAG) is a new syndrome of pituitary gigantism, caused by microduplications on chromosome Xq26.3, encompassing the gene GPR101, which is highly upregulated in pituitary tumors. We conducted this study to explore the clinical, radiological, and hormonal phenotype and responses to therapy in patients with X-LAG syndrome. The study included 18 patients (13 sporadic) with X-LAG and microduplication of chromosome Xq26.3. All sporadic cases had unique duplications and the inheritance pattern in two families was dominant, with all Xq26.3 duplication carriers being affected. Patients began to grow rapidly as early as 2-3 months of age (median 12 months). At diagnosis (median delay 27 months), patients had a median height and weight standard deviation scores (SDS) of >+3.9 SDS. Apart from the increased overall body size, the children had acromegalic symptoms including acral enlargement and facial coarsening. More than a third of cases had increased appetite. Patients had marked hypersecretion of GH/IGF1 and usually prolactin, due to a pituitary macroadenoma or hyperplasia. Primary neurosurgical control was achieved with extensive anterior pituitary resection, but postoperative hypopituitarism was frequent. Control with somatostatin analogs was not readily achieved despite moderate to high levels of expression of somatostatin receptor subtype-2 in tumor tissue. Postoperative use of adjuvant pegvisomant resulted in control of IGF1 in all five cases where it was employed. X-LAG is a new infant-onset gigantism syndrome that has a severe clinical phenotype leading to challenging disease management. PMID:25712922

  9. Earliest Example of a Giant Monitor Lizard (Varanus, Varanidae, Squamata)

    PubMed Central

    Conrad, Jack L.; Balcarcel, Ana M.; Mehling, Carl M.

    2012-01-01

    Background Varanidae is a clade of tiny (<20 mm pre-caudal length [PCL]) to giant (>600 mm PCL) lizards first appearing in the Cretaceous. True monitor lizards (Varanus) are known from diagnostic remains beginning in the early Miocene (Varanus rusingensis), although extremely fragmentary remains have been suggested as indicating earlier Varanus. The paleobiogeographic history of Varanus and timing for origin of its gigantism remain uncertain. Methodology/Principal Findings A new Varanus from the Mytilini Formation (Turolian, Miocene) of Samos, Greece is described. The holotype consists of a partial skull roof, right side of a braincase, partial posterior mandible, fragment of clavicle, and parts of six vertebrae. A cladistic analysis including 83 taxa coded for 5733 molecular and 489 morphological characters (71 previously unincluded) demonstrates that the new fossil is a nested member of an otherwise exclusively East Asian Varanus clade. The new species is the earliest-known giant (>600 mm PCL) terrestrial lizard. Importantly, this species co-existed with a diverse continental mammalian fauna. Conclusions/Significance The new monitor is larger (longer) than 99% of known fossil and living lizards. Varanus includes, by far, the largest limbed squamates today. The only extant non-snake squamates that approach monitors in maximum size are the glass-snake Pseudopus and the worm-lizard Amphisbaena. Mosasauroids were larger, but exclusively marine, and occurred only during the Late Cretaceous. Large, extant, non-Varanus, lizards are limbless and/or largely isolated from mammalian competitors. By contrast, our new Varanus achieved gigantism in a continental environment populated by diverse eutherian mammal competitors. PMID:22900001

  10. Aspergilosis cervical con diseminación al sistema nervioso central. Presentación de un caso y revisión de bibliografía

    PubMed Central

    Vergara, Guillermo Enrique; Roura, Natalia; del Castillo, Marcelo; Mora, Andrea; Alcorta, Santiago Condomi; Mormandi, Rubén; Cervio, Andrés; Salvat, Jorge

    2015-01-01

    Introducción: la Aspergilosis Invasiva (AI) del Sistema Nervioso Central (SNC) es infrecuente y ocurre generalmente en pacientes inmunocomprometidos. Puede presentarse con cuadros de meningitis, aneurismas micóticos, infartos o abscesos. Es una infección con pronóstico reservado y puede afectar el SNC de forma primaria o secundaria a partir de un foco que se disemina por vía hematógena. Presentamos el caso de un paciente con AI con invasión primaria a nivel óseo y diseminación posterior al cerebro. Caso clínico: Paciente masculino de 25 años con diagnóstico de leucemia linfática aguda en tratamiento quimioterápico que presentó neumonitis por metotrexate por lo que inicia tratamiento con corticoides. Posteriormente agregó cervicalgia y con el diagnóstico de osteomielitis cervical se realiza punción bajo tomografía computada (TC) sin aislarse gérmenes. Se colocó Halo Vest e inició tratamiento antibiótico empírico. Posteriormente presentó afasia de expresión secundaria a lesión frontal izquierda. Se realizó evacuación de absceso cerebral aislando A. fumigatus. El tratamiento antibiótico específico posterior permitió una buena respuesta clínica y radiológica. Conclusión: La presencia de lesiones en el SNC de pacientes inmunocomprometidos debe incluir a las micosis como diagnóstico diferencial. La evacuación quirúrgica permite llegar rápidamente al diagnóstico mejorando la respuesta posterior al tratamiento antibiótico. Para evaluar la respuesta terapéutica y posibles recaídas se debe realizar un seguimiento periódico clínico radiológico. Palabras clave: Aspergilosis cerebral; Aspergilosis cervical; Aspergilosis invasiva; Voriconazol. PMID:26600985

  11. Gravity Fields Generation In The Universe By The Large Range of Scales Convection Systems In Planets, Stars, Black Holes and Galaxies Based On The "Convection Bang Hypothesis"

    NASA Astrophysics Data System (ADS)

    Gholibeigian, H.; Amirshahkarami, A.; Gholibeigian, K.

    2015-12-01

    In our vision it is believed that the Big Bang was Convection Bang (CB). When CB occurred, a gigantic large-scale forced convection system (LFCS) began to create space-time including gravitons and gluons in more than light speed. Then, simultaneously by a swirling wild wind, created inflation process including many quantum convection loops (QCL) in locations which had more density of temperature and energetic particles like gravitons. QCL including fundamental particles, grew and formed black holes (BHs) as the core of galaxies. LFCSs of heat and mass in planets, stars, BHs and galaxies generate gravity and electromagnetic fields and change the properties of matter and space-time around the systems. Mechanism: Samples: 1- Due to gravity fields of Sun and Moon, Earth's inner core is dislocated toward them and rotates around the Earth's center per day and generates LFCSs, Gholibeigian [AGU, 2012]. 2- Dislocated Sun's core due to gravity fields of planets/ Jupiter, rotates around the Sun's center per 25-35 days and generates LFCSs, Gholibeigian [EGU, 2014]. 3- If a planet/star falls into a BH, what happens? It means, its dislocated core rotates around its center in less than light speed and generates very fast LFCS and friction, while it is rotating/melting around/inward the center of BH. Observable Factors: 1- There is not logical relation between surface gravity fields of planets/Sun and their masses (general relativity); see Planetary Fact Sheet/Ratio to Earth Values-NASA: Earth: mass/gravity =1/1, Jupiter=317.8/2.36, Neptune=17.1/1.12, Saturn=95.2/0.916, Moon=0.0128/0.166, Sun=333000/28. 2- Convective systems in thunderstorms help bring ozone down to Earth [Brian-Kahn]. 3- In 12 surveyed BHs, produced gravity force & magnetic field strength were matched (unique LFCS source) [PhysOrg - June 4, 2014]. Justification: After BB/CB, gravitons were created without any other masses and curvature of space-time (general relativity), but by primary gigantic convection

  12. The Climatic Observatory of the Karst (O.C.C.), a scientific facility within an important tourist framework

    NASA Astrophysics Data System (ADS)

    Colucci, R. R.; Micheletti, S.; Fabbo, R.

    2009-09-01

    The Climatic Observatory of the Karst, officially inaugurated on 2nd October, 2008, is born in the same place of the historical headquarter of the Borgo Grotta Gigante Meteorological Office, which was set up in 1966 and has been officially operating since 1st January, 1967. The meteorological facilities and the weather office are located on the premises of the visitor centre of "Grotta Gigante”, which is a very popular karstic cave of Trieste, visited each year by at least 70k people. The privileged position induced the promoters of this initiative to think about an integrated meteorological multilanguages system for the visitors. This system provides in real time weather forecasts and meteorological data and, at the same time, general tourist information as well. The synergic cooperation of various Scientific Organizations, which are involved in climatic research at the Borgo Grotta Gigante Climatic Observatory of the Karst, makes possible the realization of this project: "E.Boegan” Cave Commission of S.A.G. (the administrative body); ARPA-OSMER, the Friuli Venezia-Giulia Meteorological Observatory of the Regional Agency of the Environmental Protection, (which manages the automatic station, broadcasts and publishes data in real time and forecasts in the visitors waiting room); C.N.R.-I.S.M.A.R., the Marine Science Institute in Trieste of the National Research Council of Italy (which manages and maintains mechanical instruments, publishes data and carries out checks, files data and publishes reports); U.M.F.V.G., the Friuli Venezia Giulia Meteorological Union (which is involved in scientific dissemination activity and web sharing of information); the Environmental and Public Works Section and Water Service of the Friuli Venezia Giulia Region (water resources monitoring). Moreover one of the main characteristic of the Observatory, also because of didactic reasons, is to maintain the traditional mechanical-analogue part of data collection, carried out by

  13. Analysis of impulse signals with Hylaty ELF station

    NASA Astrophysics Data System (ADS)

    Kulak, A.; Mlynarczyk, J.; Ostrowski, M.; Kubisz, J.; Michalec, A.

    2012-04-01

    Lighting discharges generate electromagnetic field pulses that propagate in the Earth-ionosphere waveguide. The attenuation in the ELF range is so small that the pulses originating from strong atmospheric discharges can be observed even several thousand kilometers away from the individual discharge. The recorded waveform depends on the discharge process, the Earth-ionosphere waveguide properties on the source-receiver path, and the transfer function of the receiver. If the distance from the source is known, an inverse method can be used for reconstructing the current moment waveform and the charge moment of the discharge. In order to reconstruct the source parameters from the recorded signal a reliable model of the radio wave propagation in the Earth-ionosphere waveguide as well as practical signal processing techniques are necessary. We present two methods, both based on analytical formulas. The first method allows for fast calculation of the charge moment of relatively short atmospheric discharges. It is based on peak amplitude measurement of the recorded magnetic component of the ELF EM field and it takes into account the receiver characteristics. The second method, called "inverse channel method" allows reconstructing the complete current moment waveform of strong atmospheric discharges that exhibit the continuing current phase, such as Gigantic Jets and Sprites. The method makes it possible to fully remove from the observed waveform the distortions related to the receiver's impulse response as well as the influence of the Earth-ionosphere propagation channel. Our ELF station is equipped with two magnetic antennas for Bx and By components measurement in the 0.03 to 55 Hz frequency range. ELF Data recording is carried out since 1993, with continuous data acquisition since 2005. The station features low noise level and precise timing. It is battery powered and located in the sparsely populated area, far from major electric power lines, which results in high

  14. Abundância química de simbióticas na direção do bojo galáctico

    NASA Astrophysics Data System (ADS)

    Luna, G. J. M.; Costa, R. D. D.

    2003-08-01

    O estudo da distribuição de metalicidades de gigantes K no Bojo indica um largo intervalo com valores entre 0.1 a 10 vezes o valor solar. As razões elementais Ca/Fe, Si/Fe, Mg/Fe são típicas de estrelas do halo, apontando para um processo rápido de enriquecimento, via estrelas masssivas (SN's tipo II). No entanto, este cenário não combina com os resultados derivados de nebulosas planetárias do bojo tais como os de Ratag et al. (1992, A&A,255,270), Cuisinier et al.(2000, A&A,353, 543), Escudero e Costa (2001, A&A,380, 300),que obtêm abundâncias análogas às do disco. Neste cenário, o estudo de estrelas simbióticas possibilita uma abordagem particularmente apropriada para o problema das abundâncias químicas de estrelas de massa intermediária em estágios avançados da evoluçao estelar. Apresentamos aqui os resultados da determinacão das abundâncias do grupo do CNO numa extensa amostra de simbióticas do bojo. Aliás, com a disponibilidade de espectros no visível determinamos também abundâncias de Ar, Ne, S e He, fundamentais para analisar os processos de enriquecimento químico ocorridos ao longo da evolução estelar, bem como a evolução química do meio interestelar. Com os espectros UV do satelite IUE obtivemos abundâncias de C, necessárias no estudo da evolução dos sistemas. As relaçoes C/N-O/N mostram que o material nebular é produto do vento da componente gigante e não dos eventos de nova que às vezes acontecem nestes sistemas, como foi mostrado por Nussbaumer et al (1988,A&A,198,179). As abundâncias de Ar, S, Ne e O são compativeis com resultados de fontes no disco e bojo, seguindo o gradiente proposto por muitos autores na literatura a partir de diferentes objetos como cefeidas, nebulosas planetárias e anãs G. (CAPES,FAPESP,CNPq)

  15. Germline or somatic GPR101 duplication leads to X-linked acrogigantism: a clinico-pathological and genetic study.

    PubMed

    Iacovazzo, Donato; Caswell, Richard; Bunce, Benjamin; Jose, Sian; Yuan, Bo; Hernández-Ramírez, Laura C; Kapur, Sonal; Caimari, Francisca; Evanson, Jane; Ferraù, Francesco; Dang, Mary N; Gabrovska, Plamena; Larkin, Sarah J; Ansorge, Olaf; Rodd, Celia; Vance, Mary L; Ramírez-Renteria, Claudia; Mercado, Moisés; Goldstone, Anthony P; Buchfelder, Michael; Burren, Christine P; Gurlek, Alper; Dutta, Pinaki; Choong, Catherine S; Cheetham, Timothy; Trivellin, Giampaolo; Stratakis, Constantine A; Lopes, Maria-Beatriz; Grossman, Ashley B; Trouillas, Jacqueline; Lupski, James R; Ellard, Sian; Sampson, Julian R; Roncaroli, Federico; Korbonits, Márta

    2016-01-01

    Non-syndromic pituitary gigantism can result from AIP mutations or the recently identified Xq26.3 microduplication causing X-linked acrogigantism (XLAG). Within Xq26.3, GPR101 is believed to be the causative gene, and the c.924G > C (p.E308D) variant in this orphan G protein-coupled receptor has been suggested to play a role in the pathogenesis of acromegaly.We studied 153 patients (58 females and 95 males) with pituitary gigantism. AIP mutation-negative cases were screened for GPR101 duplication through copy number variation droplet digital PCR and high-density aCGH. The genetic, clinical and histopathological features of XLAG patients were studied in detail. 395 peripheral blood and 193 pituitary tumor DNA samples from acromegaly patients were tested for GPR101 variants.We identified 12 patients (10 females and 2 males; 7.8 %) with XLAG. In one subject, the duplicated region only contained GPR101, but not the other three genes in found to be duplicated in the previously reported patients, defining a new smallest region of overlap of duplications. While females presented with germline mutations, the two male patients harbored the mutation in a mosaic state. Nine patients had pituitary adenomas, while three had hyperplasia. The comparison of the features of XLAG, AIP-positive and GPR101&AIP-negative patients revealed significant differences in sex distribution, age at onset, height, prolactin co-secretion and histological features. The pathological features of XLAG-related adenomas were remarkably similar. These tumors had a sinusoidal and lobular architecture. Sparsely and densely granulated somatotrophs were admixed with lactotrophs; follicle-like structures and calcifications were commonly observed. Patients with sporadic of familial acromegaly did not have an increased prevalence of the c.924G > C (p.E308D) GPR101 variant compared to public databases.In conclusion, XLAG can result from germline or somatic duplication of GPR101. Duplication of GPR101

  16. Body Size Evolution in Insular Speckled Rattlesnakes (Viperidae: Crotalus mitchellii)

    PubMed Central

    Meik, Jesse M.; Lawing, A. Michelle; Pires-daSilva, André

    2010-01-01

    Background Speckled rattlesnakes (Crotalus mitchellii) inhabit multiple islands off the coast of Baja California, Mexico. Two of the 14 known insular populations have been recognized as subspecies based primarily on body size divergence from putative mainland ancestral populations; however, a survey of body size variation from other islands occupied by these snakes has not been previously reported. We examined body size variation between island and mainland speckled rattlesnakes, and the relationship between body size and various island physical variables among 12 island populations. We also examined relative head size among giant, dwarfed, and mainland speckled rattlesnakes to determine whether allometric differences conformed to predictions of gape size (and indirectly body size) evolving in response to shifts in prey size. Methodology/Principal Findings Insular speckled rattlesnakes show considerable variation in body size when compared to mainland source subspecies. In addition to previously known instances of gigantism on Ángel de la Guarda and dwarfism on El Muerto, various degrees of body size decrease have occurred frequently in this taxon, with dwarfed rattlesnakes occurring mostly on small, recently isolated, land-bridge islands. Regression models using the Akaike information criterion (AIC) showed that mean SVL of insular populations was most strongly correlated with island area, suggesting the influence of selection for different body size optima for islands of different size. Allometric differences in head size of giant and dwarf rattlesnakes revealed patterns consistent with shifts to larger and smaller prey, respectively. Conclusions/Significance Our data provide the first example of a clear relationship between body size and island area in a squamate reptile species; among vertebrates this pattern has been previously documented in few insular mammals. This finding suggests that selection for body size is influenced by changes in community dynamics

  17. Interplay between superconductivity and magnetism in Fe(1-x)Pd(x)Te.

    PubMed

    Karki, Amar B; Garlea, V Ovidiu; Custelcean, Radu; Stadler, Shane; Plummer, E W; Jin, Rongying

    2013-06-01

    The attractive/repulsive relationship between superconductivity and magnetic ordering has fascinated the condensed matter physics community for a century. In the early days, magnetic impurities doped into a superconductor were found to quickly suppress superconductivity. Later, a variety of systems, such as cuprates, heavy fermions, and Fe pnictides, showed superconductivity in a narrow region near the border to antiferromagnetism (AFM) as a function of pressure or doping. However, the coexistence of superconductivity and ferromagnetic (FM) or AFM ordering is found in a few compounds [RRh4B4 (R = Nd, Sm, Tm, Er), R'Mo6X8 (R' = Tb, Dy, Er, Ho, and X = S, Se), UMGe (M = Ge, Rh, Co), CeCoIn5, EuFe2(As(1-x)P(x))2, etc.], providing evidence for their compatibility. Here, we present a third situation, where superconductivity coexists with FM and near the border of AFM in Fe(1-x)Pd(x)Te. The doping of Pd for Fe gradually suppresses the first-order AFM ordering at temperature T(N/S), and turns into short-range AFM correlation with a characteristic peak in magnetic susceptibility at T'(N). Superconductivity sets in when T'(N) reaches zero. However, there is a gigantic ferromagnetic dome imposed in the superconducting-AFM (short-range) cross-over regime. Such a system is ideal for studying the interplay between superconductivity and two types of magnetic (FM and AFM) interactions. PMID:23690601

  18. The change of amyloplasts structure and composition of storage starch in potato minitubers during imitated microgravity

    NASA Astrophysics Data System (ADS)

    Nedukha, O. M.; Kordyum, E. L.; Martyn, G. M.; Schnyukova, E. I.

    Potato was designated for food production in the controlled ecological life-support system CELSS because its tubers as it is known contain starch and significant protein content and are edible food after the long-term storage We used the cultivation of potato miniplants under influence of long-term horizontal clinorotation 2 rev min which imitated microgravity as a model for the technology of potato food production in the CELSS The aim of our work was to determine content and composition storage starch as well as amyloplast ultrastructure of storage parenchyma cells in potato minitubers formed under long-term to 6 weeks slow horizontal clinorotation 2 rpm Minitubers developed from axillary buds of potato miniplants growing in the aseptic stationary conditions and under clinorotation Methods of scanning and transmission electron microscopy were used for the study of surface and ultrastructure of amyloplasts the biochemical method by Hovenkamp-Hermelink et al 1988 - for study of starch composition Some differences were observed in amyloplast structure under clinorotation namely increased volume of starch grains in plastid decreased stroma volume changed structure of envelope membranes in comparison with the stationary control Besides an appearance of fraction of gigantic amyloplasts in central layers of parenchyma was observed under clinorotation after 4 weeks of growth The total starch content increased and reached to 219 5 - 4 1 mg g FW at 6 weeks of clinorotation it was 167 5 - 5 6 mg g FW in the control minitubers A ratio of

  19. Oriented feldspar-feldspathoid intergrowths in rocks of the Khibiny massif: genetic implications

    NASA Astrophysics Data System (ADS)

    Ageeva, Olga A.; Abart, Rainer; Habler, Gerlinde; Ye. Borutzky, Boris; Trubkin, Nikolay V.

    2012-09-01

    Poikilitic megacrysts of alkali feldspar with abundant inclusions of feldspar-nepheline and feldspar-kalsilite micrographic or lamellar intergrowths are characteristic for the rischorrites of the Khibiny massif. Strict crystallographic orientation relations were identified among the intergrowth phases based on optical investigation using a 4-axes universal stage and crystal orientation imaging using electron back scatter diffraction. The most frequently observed orientation relation is the parallel orientation of the kalsilite and nepheline [001] directions with the [010] direction of the alkali feldspar host and concomitant coincidence of the feldspathoid [100] directions with the [100]-, [101]- and [001] directions of the alkali feldspar. The presence of relic nepheline within intergrowth domains and the successive replacement of precursor nepheline by alkali feldspar and associated formation of feldspar-feldspathoid intergrowth suggest development of the rischorrites from feldspar urtites, in which nepheline is the dominant felsic phase. The metasomatic nature of the transformation of urtites to rischorrites is identified from massive introduction of potassium and silica and removal of sodium. Metasomatism occurred at high temperature; the gigantic apatite deposits of the Khibiny massif seem to be related to this metasomatic event.

  20. Lowland-upland migration of sauropod dinosaurs during the Late Jurassic epoch.

    PubMed

    Fricke, Henry C; Hencecroth, Justin; Hoerner, Marie E

    2011-12-22

    Sauropod dinosaurs were the largest vertebrates ever to walk the Earth, and as mega-herbivores they were important parts of terrestrial ecosystems. In the Late Jurassic-aged Morrison depositional basin of western North America, these animals occupied lowland river-floodplain settings characterized by a seasonally dry climate. Massive herbivores with high nutritional and water needs could periodically experience nutritional and water stress under these conditions, and thus the common occurrence of sauropods in this basin has remained a paradox. Energetic arguments and mammalian analogues have been used to suggest that migration allowed sauropods access to food and water resources over a wide region or during times of drought or both, but there has been no direct support for these hypotheses. Here we compare oxygen isotope ratios (δ(18)O) of tooth-enamel carbonate from the sauropod Camarasaurus with those of ancient soil, lake and wetland (that is, 'authigenic') carbonates that formed in lowland settings. We demonstrate that certain populations of these animals did in fact undertake seasonal migrations of several hundred kilometres from lowland to upland environments. This ability to describe patterns of sauropod movement will help to elucidate the role that migration played in the ecology and evolution of gigantism of these and associated dinosaurs. PMID:22031326

  1. The changing pace of insular life: 5000 years of microevolution in the Orkney vole (Microtus arvalis orcadensis).

    PubMed

    Cucchi, Thomas; Barnett, Ross; Martínková, Natália; Renaud, Sabrina; Renvoisé, Elodie; Evin, Allowen; Sheridan, Alison; Mainland, Ingrid; Wickham-Jones, Caroline; Tougard, Christelle; Quéré, Jean Pierre; Pascal, Michel; Pascal, Marine; Heckel, Gerald; O'Higgins, Paul; Searle, Jeremy B; Dobney, Keith M

    2014-10-01

    Island evolution may be expected to involve fast initial morphological divergence followed by stasis. We tested this model using the dental phenotype of modern and ancient common voles (Microtus arvalis), introduced onto the Orkney archipelago (Scotland) from continental Europe some 5000 years ago. First, we investigated phenotypic divergence of Orkney and continental European populations and assessed climatic influences. Second, phenotypic differentiation among Orkney populations was tested against geography, time, and neutral genetic patterns. Finally, we examined evolutionary change along a time series for the Orkney Mainland. Molar gigantism and anterior-lobe hypertrophy evolved rapidly in Orkney voles following introduction, without any transitional forms detected. Founder events and adaptation appear to explain this initial rapid evolution. Idiosyncrasy in dental features among different island populations of Orkney voles is also likely the result of local founder events following Neolithic translocation around the archipelago. However, against our initial expectations, a second marked phenotypic shift occurred between the 4th and 12th centuries AD, associated with increased pastoral farming and introduction of competitors (mice and rats) and terrestrial predators (foxes and cats). These results indicate that human agency can generate a more complex pattern of morphological evolution than might be expected in island rodents. PMID:24957579

  2. An archaic crested plesiosaur in opal from the Lower Cretaceous high-latitude deposits of Australia.

    PubMed

    Kear, Benjamin P; Schroeder, Natalie I; Lee, Michael S Y

    2006-12-22

    Umoonasaurus demoscyllus gen. et sp. nov. is a new small-bodied (approx. 2.5m) pliosauroid plesiosaur from the Lower Cretaceous (Aptian-Albian) of southern Australia. It is represented by several partial skeletons (one with a near complete skull is the most complete opalized vertebrate fossil yet known), and is unique in having large crests on the skull midline and above the orbits. Umoonasaurus is surprisingly archaic despite its relatively late age (approx. 115 Myr ago)--being simultaneously the most basal (primitive) and last surviving rhomaleosaurid. Notably, it lacks the 'pliosauromorph' features (large head, short neck, gigantism) typically characterizing many more derived Jurassic rhomaleosaurids; thus, reinforcing the suspected convergent evolution of the 'pliosauromorph' hypercarnivore body plan. Umoonasaurus inhabited an Early Cretaceous high-latitude (approx. 70 degrees S) inland seaway subject to seasonally near-freezing climatic conditions. This extreme environment supported a diverse range of plesiosaur taxa, suggesting that these marine reptiles might have possessed adaptations (e.g. heightened metabolic levels) to cope with cold-water temperatures. Indeed, survival of ancient endemic lineages such as Umoonasaurus is a common phenomenon in Australian Cretaceous vertebrate assemblages and might have been facilitated by isolation in low-temperature high-latitude regions. PMID:17148303

  3. Study of Historical 4B/X17 Mega Flare on 28 October 2003 (P58)

    NASA Astrophysics Data System (ADS)

    Uddin, W.; Chandra, R.; Ali, S. S.

    2006-11-01

    wuddin_99@yahoo.com We analysed multi-wavelength data of 28 October 2003 4B/X17.2 class extremely energetic parallel ribbon solar flare, which occurred in NOAA 10486. The flare was well observed in H-alpha at ARIES, Nainital and various space (SOHO, TRACE, RHESSI, WIND etc.) and ground based Observatories. The H-alpha observations show the stretching/detwisting and eruption of helically twisted S shaped (sigmoid) filament in the South-West direction of the active region with bright shock front followed by rapid increase in intensity and area of the gigantic flare. The flare is associated with a bright/fast full halo earth directed CME, strong type II, III and IV radio bursts, an intense proton event and GLE. It seems that the filament eruption triggered the halo CME because the helical structure is clearly visible in the SOHO/LASCO C2, C3 images. This indicates helicity transfer from chromosphere to corona and interplanetary medium. The magnetic field of the flaring region was most complex with high magnetic shear. From the above analysis we feel that the energy buildup/release process of this unique flare support helically twisted magnetic flux rope model.

  4. The Kunlun Fault

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Kunlun fault is one of the gigantic strike-slip faults that bound the north side of Tibet. Left-lateral motion along the 1,500-kilometer (932-mile) length of the Kunlun has occurred uniformly for the last 40,000 years at a rate of 1.1 centimeter per year, creating a cumulative offset of more than 400 meters. In this image, two splays of the fault are clearly seen crossing from east to west. The northern fault juxtaposes sedimentary rocks of the mountains against alluvial fans. Its trace is also marked by lines of vegetation, which appear red in the image. The southern, younger fault cuts through the alluvium. A dark linear area in the center of the image is wet ground where groundwater has ponded against the fault. Measurements from the image of displacements of young streams that cross the fault show 15 to 75 meters (16 to 82 yards) of left-lateral offset. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) acquired the visible light and near infrared scene on July 20, 2000. Image courtesy NASA/GSFC/MITI/ERSDAC/JAROS, and the U.S./Japan ASTER Science Team

  5. Genetic characterization of four native Italian shepherd dog breeds and analysis of their relationship to cosmopolitan dog breeds using microsatellite markers.

    PubMed

    Bigi, D; Marelli, S P; Randi, E; Polli, M

    2015-12-01

    Very little research into genetic diversity of Italian native dog breeds has been carried out so far. In this study we aimed to estimate and compare the genetic diversity of four native Italian shepherd dog breeds: the Maremma, Bergamasco, Lupino del Gigante and Oropa shepherds. Therefore, some cosmopolitan dog breeds, which have been widely raised in Italy for a long time past, have also been considered to check possible influence of these dog populations on the Italian autochthonous breeds considered here. A total of 212 individuals, belonging to 10 different dog breeds, were sampled and genotyped using 18 autosomal microsatellite loci. We analyzed the genetic diversity of these breeds, within breed diversity, breed relationship and population structure. The 10 breeds considered in this study were clearly genetically differentiated from each other, regardless of current population sizes and the onset of separate breeding history. The level of genetic diversity explained 20% of the total genetic variation. The level of H E found here is in agreement with that found by other studies. The native Italian breeds showed generally higher genetic diversity compared with the long established, well-defined cosmopolitan dog breeds. As the Border Collie seems closer to the Italian breeds than the other cosmopolitan shepherd dogs considered here, a possible utilization of this breed to improve working performance in Italian traditional working shepherd dogs cannot be ignored. The data and information found here can be utilized in the organization of conservation programs planned to reduce inbreeding and to minimize loss of genetic variability. PMID:26245492

  6. Parasitism and phenotypic change in colonial hosts.

    PubMed

    Hartikainen, Hanna; Fontes, Inês; Okamura, Beth

    2013-09-01

    Changes in host phenotype are often attributed to manipulation that enables parasites to complete trophic transmission cycles. We characterized changes in host phenotype in a colonial host–endoparasite system that lacks trophic transmission (the freshwater bryozoan Fredericella sultana and myxozoan parasite Tetracapsuloides bryosalmonae). We show that parasitism exerts opposing phenotypic effects at the colony and module levels. Thus, overt infection (the development of infectious spores in the host body cavity) was linked to a reduction in colony size and growth rate, while colony modules exhibited a form of gigantism. Larger modules may support larger parasite sacs and increase metabolite availability to the parasite. Host metabolic rates were lower in overtly infected relative to uninfected hosts that were not investing in propagule production. This suggests a role for direct resource competition and active parasite manipulation (castration) in driving the expression of the infected phenotype. The malformed offspring (statoblasts) of infected colonies had greatly reduced hatching success. Coupled with the severe reduction in statoblast production this suggests that vertical transmission is rare in overtly infected modules. We show that although the parasite can occasionally infect statoblasts during overt infections, no infections were detected in the surviving mature offspring, suggesting that during overt infections, horizontal transmission incurs a trade-off with vertical transmission. PMID:23965820

  7. When Did Carcharocles megalodon Become Extinct? A New Analysis of the Fossil Record

    PubMed Central

    Pimiento, Catalina; Clements, Christopher F.

    2014-01-01

    Carcharocles megalodon (“Megalodon”) is the largest shark that ever lived. Based on its distribution, dental morphology, and associated fauna, it has been suggested that this species was a cosmopolitan apex predator that fed on marine mammals from the middle Miocene to the Pliocene (15.9–2.6 Ma). Prevailing theory suggests that the extinction of apex predators affects ecosystem dynamics. Accordingly, knowing the time of extinction of C. megalodon is a fundamental step towards understanding the effects of such an event in ancient communities. However, the time of extinction of this important species has never been quantitatively assessed. Here, we synthesize the most recent records of C. megalodon from the literature and scientific collections and infer the date of its extinction by making a novel use of the Optimal Linear Estimation (OLE) model. Our results suggest that C. megalodon went extinct around 2.6 Ma. Furthermore, when contrasting our results with known ecological and macroevolutionary trends in marine mammals, it became evident that the modern composition and function of modern gigantic filter-feeding whales was established after the extinction of C. megalodon. Consequently, the study of the time of extinction of C. megalodon provides the basis to improve our understanding of the responses of marine species to the removal of apex predators, presenting a deep-time perspective for the conservation of modern ecosystems. PMID:25338197

  8. PLPP/CIN regulates bidirectional synaptic plasticity via GluN2A interaction with postsynaptic proteins

    PubMed Central

    Kim, Ji-Eun; Kim, Yeon-Joo; Lee, Duk-Shin; Kim, Ji Yang; Ko, Ah-Reum; Hyun, Hye-Won; Kim, Min Ju; Kang, Tae-Cheon

    2016-01-01

    Dendritic spines are dynamic structures whose efficacies and morphologies are modulated by activity-dependent synaptic plasticity. The actin cytoskeleton plays an important role in stabilization and structural modification of spines. However, the regulatory mechanism by which it alters the plasticity threshold remains elusive. Here, we demonstrate the role of pyridoxal-5′-phosphate phosphatase/chronophin (PLPP/CIN), one of the cofilin-mediated F-actin regulators, in modulating synaptic plasticity in vivo. PLPP/CIN transgenic (Tg) mice had immature spines with small heads, while PLPP/CIN knockout (KO) mice had gigantic spines. Furthermore, PLPP/CIN Tg mice exhibited enhanced synaptic plasticity, but KO mice showed abnormal synaptic plasticity. The PLPP/CIN-induced alterations in synaptic plasticity were consistent with the acquisition and the recall capacity of spatial learning. PLPP/CIN also enhanced N-methyl-D-aspartate receptor (GluN) functionality by regulating the coupling of GluN2A with interacting proteins, particularly postsynaptic density-95 (PSD95). Therefore, these results suggest that PLPP/CIN may be an important factor for regulating the plasticity threshold. PMID:27212638

  9. Morphogenetic Mechanisms in the Cyclic Regeneration of Hair Follicles and Deer Antlers from Stem Cells

    PubMed Central

    Li, Chunyi; McMahon, Chris

    2013-01-01

    We have made comparisons between hair follicles (HFs) and antler units (AUs)—two seemingly unrelated mammalian organs. HFs are tiny and concealed within skin, whereas AUs are gigantic and grown externally for visual display. However, these two organs share some striking similarities. Both consist of permanent and cyclic/temporary components and undergo stem-cell-based organogenesis and cyclic regeneration. Stem cells of both organs reside in the permanent part and the growth centres are located in the temporary part of each respective organ. Organogenesis and regeneration of both organs depend on epithelial-mesenchymal interactions. Establishment of these interactions requires stem cells and reactive/niche cells (dermal papilla cells for HFs and epidermal cells for AUs) to be juxtaposed, which is achieved through destruction of the cyclic part to bring the reactive cells into close proximity to the respective stem cell niche. Developments of HFs and AUs are regulated by similar endocrine (particularly testosterone) and paracrine (particularly IGF1) factors. Interestingly, these two organs come to interplay during antlerogenesis. In conclusion, we believe that investigators from the fields of both HF and AU biology could greatly benefit from a comprehensive comparison between these two organs. PMID:24383056

  10. Neutral Middle Atmospheric Influences by the Extremely Large October 2003 Solar Proton

    NASA Technical Reports Server (NTRS)

    Jackman, C. H.; Fleming, E. L.

    2004-01-01

    The huge coronal mass ejection (CME) on October 28, 2003 caused an extremely large solar proton event (SPE) 3t the Earth, which impacted the middle atmospheric polar cap regions. The highly energetic protons produce ionizations, excitations, dissociations, and dissociative ionizations of the background constituents, which lead to the production of HO(x) (H, OH, HO2) and NO(y) (N, NO, NO2, NO3, N2O5, HNO3, HO2NO2, ClONO2, BrONO2). The total production of middle atmospheric NO(y) molecules by individual SPEs can be used to compare their sizes. Using this scale, the extremely large October 2003 SPE was the fourth largest in the past 40 years and the second largest of solar cycle 23. Only the October 1989, August 1972, and July 2000 SPEs were larger. The Goddard Space Flight Center (CSFC) Two-dimensional (2D)) Model was used in computing the influence of this gigantic SPE The NO(y) amount was increased by over two orders of Atmosphere Research Satellite (UARS) Halogen Occultation Experiment (HALOE) measurements as a result of this noteworthy SPE. The model also calculated polar middle mesosphere ozone decreases of over 70% during the SPE. Other atmospheric impacts from both model predictions and measurements as a result of this major SPE will be discussed in this paper.

  11. Neutral Middle Atmospheric Influences by the Extremely Large October 2003 Solar Proton Event

    NASA Technical Reports Server (NTRS)

    Jackman, C. H.; Fleming, E. L.

    2004-01-01

    The huge coronal mass ejection (CME) on October 28,2003 caused an extremely large solar proton event (SPE) at the Earth, which impacted the middle atmospheric polar cap regions. The highly energetic protons produce ionizations, excitations, dissociations, and dissociative ionizations of the background constituents, which lead to the production of HOx (H, OH, HO2) and NOy (N, NO, NO2, NO3, N2O5, HNO3, HO2NO2, ClONO2, BrONO2). The total production of middle atmospheric NOy molecules by individual SPEs can be used to compare their sizes. Using this scale, the extremely large October 2003 SPE was the fourth largest in the past 40 years and the second largest of solar cycle 23. Only the October 1989, August 1972, and July 2000 SPEs were larger. The Goddard Space Flight Center (GSFC) Two-dimensional (2D) Model was used in computing the influence of this gigantic SPE. The NOy amount was increased by over two orders of magnitude in the mesosphere in both the GSFC 2D Model computations and Upper Atmosphere Research Satellite (UARS) Halogen Occultation Experiment (HALOE) measurements as a result of this noteworthy SPE. The model also calculated polar middle mesospheric ozone decreases of over 70% during the SPE. Other atmospheric impacts from both model predictions and measurements as a result of this major SPE will be discussed in this paper.

  12. Landslides in Valles Marineris, Mars

    NASA Technical Reports Server (NTRS)

    Lucchitta, B. K.

    1979-01-01

    The morphology of the landslides in the Martian equatorial troughs, the geologic structure of the troughs, the time of emplacement, the similarity to terrestrial landslides, and the origin and mechanism of transport are analyzed. About 35 large landslides well-resolved on Viking images were examined, and it is found that the major landslides cover 31,000 sq km of the trough floors, and individual slides range in area from 40 to 7000 sq km. The morphologic variations of the landslides can be attributed mainly to their degree of confinement on trough floors. Many prominent landslides appear to be of similar age and were emplaced after a major faulting that dropped the trough floors. Most sliding occurred after the created scarps were dissected into spurs, gullies, and tributary canyons. Emplacement of the landslides approximately coincided with a late episode of major eruptive activity of the Tharsis volcanoes, and it is suggested that the slides may have originated as gigantic mudflows with slump blocks at their heads. The large size of many landslides is due to the fault scarps as high as 7 km on which they formed in the absence of vigorous fluvial erosion. The landslides suggest that Mars is earthlike in some respects, which may be important for further evaluations.

  13. Rb-Sr, Sm-Nd, K-Ca, O, and H isotopic study of Cretaceous-Tertiary boundary sediments, Caravaca, Spain Evidence for an oceanic impact site

    NASA Technical Reports Server (NTRS)

    Depaolo, D. J.; Kyte, F. T.; Marshall, B. D.; Oneil, J. R.; Smit, J.

    1983-01-01

    The results of isotopic and trace-element-abundance analyses of Ir-enriched Cretaceous-Tertiary-boundary clay sediments from Caravaca, Spain, and of adjacent carbonate and marl layers, are presented. Acetic-acid and HCl leachates and residues were analyzed by isotope dilution to determine K, Rb, Sr, Sm, and Nd concentrations and Sr-87/Sr-86 and Nd-143/Nd-144 ratios. The stable isotope ratios delta-D, delta-(C-13), and delta-(0-18) were also determined. The results are presented in tables and graphs and compared with published data on the Caravaca sediments and on samples from other locations. The boundary clay is found to be distinguished from the adjacent layers by its isotopic ratios and to be of mainly terrestrial, lithospheric (deeper than 3-km) origin. Although submarine-weathering effects are evident and difficult to quantify, the degree of variation in Ni, Ir, Sr, and REE concentrations is considered too large to be attributed to postdepositional processes alone. These findings are seen as evidence for the ocean impact of a large single asteroid producing a worldwide blanket of ejecta, a large injection of water vapor into the atmosphere, and perhaps a gigantic tsunami, at the end of the Cretaceous period.

  14. Development of a CME-associated geomagnetic storm intensity prediction tool

    NASA Astrophysics Data System (ADS)

    Wu, C. C.; DeHart, J. M.

    2015-12-01

    From 1995 to 2012, the Wind spacecraft recorded 168 magnetic cloud (MC) events. Among those events, 79 were found to have upstream shock waves and their source locations on the Sun were identified. Using a recipe of interplanetary magnetic field (IMF) Bz initial turning direction after shock (Wu et al., 1996, GRL), it is found that the north-south polarity of 66 (83.5%) out of the 79 events were accurately predicted. These events were tested and further analyzed, reaffirming that the Bz intial turning direction was accurate. The results also indicate that 37 of the 79 MCs originate from the north (of the Sun) averaged a Dst_min of -119 nT, whereas 42 of the MCs originating from the south (of the Sun) averaged -89 nT. In an effort to provide this research to others, a website was built that incorporated various tools and pictures to predict the intensity of the geomagnetic storms. The tool is capable of predicting geomagnetic storms with different ranges of Dst_min (from no-storm to gigantic storms). This work was supported by Naval Research Lab HBCU/MI Internship program and Chief of Naval Research.

  15. How sexual selection can drive the evolution of costly sperm ornamentation.

    PubMed

    Lüpold, Stefan; Manier, Mollie K; Puniamoorthy, Nalini; Schoff, Christopher; Starmer, William T; Luepold, Shannon H Buckley; Belote, John M; Pitnick, Scott

    2016-05-26

    Post-copulatory sexual selection (PSS), fuelled by female promiscuity, is credited with the rapid evolution of sperm quality traits across diverse taxa. Yet, our understanding of the adaptive significance of sperm ornaments and the cryptic female preferences driving their evolution is extremely limited. Here we review the evolutionary allometry of exaggerated sexual traits (for example, antlers, horns, tail feathers, mandibles and dewlaps), show that the giant sperm of some Drosophila species are possibly the most extreme ornaments in all of nature and demonstrate how their existence challenges theories explaining the intensity of sexual selection, mating-system evolution and the fundamental nature of sex differences. We also combine quantitative genetic analyses of interacting sex-specific traits in D. melanogaster with comparative analyses of the condition dependence of male and female reproductive potential across species with varying ornament size to reveal complex dynamics that may underlie sperm-length evolution. Our results suggest that producing few gigantic sperm evolved by (1) Fisherian runaway selection mediated by genetic correlations between sperm length, the female preference for long sperm and female mating frequency, and (2) longer sperm increasing the indirect benefits to females. Our results also suggest that the developmental integration of sperm quality and quantity renders post-copulatory sexual selection on ejaculates unlikely to treat male-male competition and female choice as discrete processes. PMID:27225128

  16. Molecular Characterization of Growth Hormone-producing Tumors in the GC Rat Model of Acromegaly

    PubMed Central

    Martín-Rodríguez, Juan F.; Muñoz-Bravo, Jose L.; Ibañez-Costa, Alejandro; Fernandez-Maza, Laura; Balcerzyk, Marcin; Leal-Campanario, Rocío; Luque, Raúl M.; Castaño, Justo P.; Venegas-Moreno, Eva; Soto-Moreno, Alfonso; Leal-Cerro, Alfonso; Cano, David A.

    2015-01-01

    Acromegaly is a disorder resulting from excessive production of growth hormone (GH) and consequent increase of insulin-like growth factor 1 (IGF-I), most frequently caused by pituitary adenomas. Elevated GH and IGF-I levels results in wide range of somatic, cardiovascular, endocrine, metabolic, and gastrointestinal morbidities. Subcutaneous implantation of the GH-secreting GC cell line in rats leads to the formation of tumors. GC tumor-bearing rats develop characteristics that resemble human acromegaly including gigantism and visceromegaly. However, GC tumors remain poorly characterized at a molecular level. In the present work, we report a detailed histological and molecular characterization of GC tumors using immunohistochemistry, molecular biology and imaging techniques. GC tumors display histopathological and molecular features of human GH-producing tumors, including hormone production, cell architecture, senescence activation and alterations in cell cycle gene expression. Furthermore, GC tumors cells displayed sensitivity to somatostatin analogues, drugs that are currently used in the treatment of human GH-producing adenomas, thus supporting the GC tumor model as a translational tool to evaluate therapeutic agents. The information obtained would help to maximize the usefulness of the GC rat model for research and preclinical studies in GH-secreting tumors. PMID:26549306

  17. Ion Characteristics in Jupiter's Magnetotail from New Horizon data

    NASA Astrophysics Data System (ADS)

    Hui, Debrup; Su, Yi-Jiun; Elliott, Heather; McComas, Dave; Bagenal, Fran; Crary, Frank

    2009-04-01

    Jupiter's gigantic magnetotail, extending 2500 Jovian radii, is the largest cohesive structure in our solar system. For the first time, NASA's New Horizons (NH) satellite in 2007 traversed almost axially. Data from its onboard SWAP instrument (Solar Wind Around Pluto), which makes coincidence measurements of the ions shows many periodic structures and existence of light and heavy ion species with varying densities in Jupiter's magnetotail plasma population. A better understanding of the physical processes governing such diversity requires knowing the characteristics of the various charged particles present, such as the ion density, velocity, temperature, and pressure. We have developed a 3-dimensional phase-space distribution model by constructing the observed signatures along with the calibration parameters provided by the SWAP team during the NH magnetotail flyby. The model uses five input parameters from SWAP. A 3-D isotropic Maxwellian distribution function is used to estimate density, velocity, and temperature, which is then converted into counts as the instrument measures the count rates. Finally, minimizing the chi-square fitting of our model results in the maximum likelihood of the various parameters. We will show our results from 500-800 RJ.

  18. Quantifying distal dispersal and impact of volcanic ash from super-eruptions: an application to Campanian Ignimbrite

    NASA Astrophysics Data System (ADS)

    Costa, A.; Folch, A.; Macedonio, G.; Giaccio, B.; Isaia, R.; Smith, V. C.

    2012-04-01

    Distal and ultra-distal volcanic ash dispersal during a super-eruption was reconstructed for the first time, providing insights into eruption dynamics and the impact of these gigantic events. A novel computational methodology was applied to the ash fallout of the Campanian Ignimbrite (CI), the most powerful volcanic eruption in Europe in the last 200 kyrs. The method uses a 3D time-dependent computational ash dispersion model, an ensemble of wind fields, and hundreds of thickness observations of the CI tephra deposit. Results reveal that 250-300 km3 of fallout material was produced during the eruption, blanketing a region of ~3.7 million km2 with more than 5 mm of fine ash. The model also indicates that the column height was ~37-40 km, and the eruption lasted 2-4 days. The eruption would have caused a volcanic winter within the coldest and driest Heinrich event. Fluorine-bearing leachate from the volcanic ash and acid rain would have further affected food sources and severely impacted Late Middle Paleolithic groups in Southern and Eastern Europe.

  19. Before the Giants: APASS Support to Ambitious Ground-based Galaxy Investigations and Space Missions Serching for Exo-Earths (Abstract)

    NASA Astrophysics Data System (ADS)

    Munari, U.

    2015-06-01

    (Abstract only) A huge, worldwide effort is underway to reconstruct the structure, kinematics and evolution of our Galaxy with optical spectroscopic techniques, which provide radial velocities and individual chemical abundances in addition to derive fundamental stellar parameters like surface temperature and gravity. RAVE has used for ten years (2003-2013) the 6dF 150-fiber positioner at the 1.3-meter UK Schmidt telescope in Siding Spring, ESO-Gaia has hundreds of nights allocated at the VLT telescopes in Chile with UVES and GIRAFFE multi-fiber instruments, GALAH has been allocated 400 nights in five years with the 400-fiber HERMES spectrograph at the 4-meter Australian telescope. Common to the millions of stars targeted by these surveys (over the range 10 < V < 16 mag) is the lack of suitable, multi-band, accurate optical photometry. In this talk, I review the fundamental role played by APASS in providing such missing photometric information for the stars targeted by these gigantic spectroscopic surveys. The APASS BVgri data are fundamental to support the spectroscopic effort, for example to constrain (when modelled together with 2MASS infrared JHK photometry) the stellar temperature. The APASS data are also crucial in fixing the interstellar reddening and the distance to the target stars, and their importance will be further expanded when APASS ultraviolet (u) and far red (z,Y) magnitudes will become available, as well the unsaturated APASS extension to brighter stars so that most of the bright spectroscopic standards will become within photometric reach.

  20. How sexual selection can drive the evolution of costly sperm ornamentation

    NASA Astrophysics Data System (ADS)

    Lüpold, Stefan; Manier, Mollie K.; Puniamoorthy, Nalini; Schoff, Christopher; Starmer, William T.; Luepold, Shannon H. Buckley; Belote, John M.; Pitnick, Scott

    2016-05-01

    Post-copulatory sexual selection (PSS), fuelled by female promiscuity, is credited with the rapid evolution of sperm quality traits across diverse taxa. Yet, our understanding of the adaptive significance of sperm ornaments and the cryptic female preferences driving their evolution is extremely limited. Here we review the evolutionary allometry of exaggerated sexual traits (for example, antlers, horns, tail feathers, mandibles and dewlaps), show that the giant sperm of some Drosophila species are possibly the most extreme ornaments in all of nature and demonstrate how their existence challenges theories explaining the intensity of sexual selection, mating-system evolution and the fundamental nature of sex differences. We also combine quantitative genetic analyses of interacting sex-specific traits in D. melanogaster with comparative analyses of the condition dependence of male and female reproductive potential across species with varying ornament size to reveal complex dynamics that may underlie sperm-length evolution. Our results suggest that producing few gigantic sperm evolved by (1) Fisherian runaway selection mediated by genetic correlations between sperm length, the female preference for long sperm and female mating frequency, and (2) longer sperm increasing the indirect benefits to females. Our results also suggest that the developmental integration of sperm quality and quantity renders post-copulatory sexual selection on ejaculates unlikely to treat male–male competition and female choice as discrete processes.

  1. Mantle insulation beneath the West African craton during the Precambrian-Cambrian transition

    NASA Astrophysics Data System (ADS)

    Doblas, Miguel; López-Ruiz, José; Cebriá, José-María; Youbi, Nasrrddine; Degroote, Eugenio

    2002-09-01

    At the time of the Precambrian-Cambrian transition, the West African craton underwent widespread magmatism, hydrothermal activity, and thermal rejuvenation. This tectonothermal event gave rise to an anorogenic “ring of fire” along the rim of this craton, following the Pan-African Brasiliano belt that was reactivated by extension and transtension. The thermal phenomena were due to the progressive peripheral release of mantle heat that had built up beneath this craton because of strong insulating conditions. The West African craton at the Precambrian-Cambrian transition can thus be envisioned in terms of a gigantic pressure-cooker with a thick blanketing lithospheric lid. These insulation processes triggered an unusually hot mantle that was channeled by edge-driven convection toward the peri West African craton extensional corridors and released through magmatic pressure-relief valves. Massive ice melting and outgassing of volcanic CO2 gave rise to a planet-scale sea-level rise, a greenhouse effect, and the end of the icehouse snowball Earth. These processes played an important role in the Phanerozoic explosion of life on Earth.

  2. Giant lizards occupied herbivorous mammalian ecospace during the Paleogene greenhouse in Southeast Asia

    PubMed Central

    Head, Jason J.; Gunnell, Gregg F.; Holroyd, Patricia A.; Hutchison, J. Howard; Ciochon, Russell L.

    2013-01-01

    Mammals dominate modern terrestrial herbivore ecosystems, whereas extant herbivorous reptiles are limited in diversity and body size. The evolution of reptile herbivory and its relationship to mammalian diversification is poorly understood with respect to climate and the roles of predation pressure and competition for food resources. Here, we describe a giant fossil acrodontan lizard recovered with a diverse mammal assemblage from the late middle Eocene Pondaung Formation of Myanmar, which provides a historical test of factors controlling body size in herbivorous squamates. We infer a predominately herbivorous feeding ecology for the new acrodontan based on dental anatomy, phylogenetic relationships and body size. Ranking body masses for Pondaung Formation vertebrates indicates that the lizard occupied a size niche among the larger herbivores and was larger than most carnivorous mammals. Paleotemperature estimates of Pondaung Formation environments based on the body size of the new lizard are approximately 2–5°C higher than modern. These results indicate that competitive exclusion and predation by mammals did not restrict body size evolution in these herbivorous squamates, and elevated temperatures relative to modern climates during the Paleogene greenhouse may have resulted in the evolution of gigantism through elevated poikilothermic metabolic rates and in response to increases in floral productivity. PMID:23740779

  3. Polarización lineal en estrellas simbióticas

    NASA Astrophysics Data System (ADS)

    Brandi, E.; García, L. G.; Ferrer, O. E.

    Se presenta un estudio de polarización lineal en las bandas UBVRI de un grupo de estrellas simbióticas, a fin de analizar el comportamiento del grado de polarización y del ángulo de posición en función de la longitud de onda. En aquellos sistemas observados repetidas veces, se analizan además variaciones temporales en los parámetros de polarización. En base a este comportamiento se determina si la polarización observada es puramente interestelar o si existe una contribución de polarización, intrínseca al objeto. La muestra de objetos estudiados presenta ciertas características comunes, es decir, son sistemas simbióticos tipo D, cuyas respectivas componentes gigantes son variables tipo Mira y además presentan nebulosas ionizadas extendidas con morfología y dimensiones conocidas. Esto es de importancia ya que el conocimiento de la estructura del gas extendido permite interpretar la geometría de scattering que produce la polarización observada. Las observaciones fueron realizadas con el Fotopolarímetro de Torino adosado al telescopio de 2.15 m del CASLEO.

  4. Martian outflow channels: How did their source aquifers form, and why did they drain so rapidly?

    PubMed

    Rodriguez, J Alexis P; Kargel, Jeffrey S; Baker, Victor R; Gulick, Virginia C; Berman, Daniel C; Fairén, Alberto G; Linares, Rogelio; Zarroca, Mario; Yan, Jianguo; Miyamoto, Hideaki; Glines, Natalie

    2015-01-01

    Catastrophic floods generated ~3.2 Ga by rapid groundwater evacuation scoured the Solar System's most voluminous channels, the southern circum-Chryse outflow channels. Based on Viking Orbiter data analysis, it was hypothesized that these outflows emanated from a global Hesperian cryosphere-confined aquifer that was infused by south polar meltwater infiltration into the planet's upper crust. In this model, the outflow channels formed along zones of superlithostatic pressure generated by pronounced elevation differences around the Highland-Lowland Dichotomy Boundary. However, the restricted geographic location of the channels indicates that these conditions were not uniform. Furthermore, some outflow channel sources are too high to have been fed by south polar basal melting. Using more recent mission data, we argue that during the Late Noachian fluvial and glacial sediments were deposited into a clastic wedge within a paleo-basin located in the southern circum-Chryse region, which at the time was completely submerged under a primordial northern plains ocean [corrected]. Subsequent Late Hesperian outflow channels were sourced from within these geologic materials and formed by gigantic groundwater outbursts driven by an elevated hydraulic head from the Valles Marineris region. Thus, our findings link the formation of the southern circum-Chryse outflow channels to ancient marine, glacial, and fluvial erosion and sedimentation. PMID:26346067

  5. The First Freshwater Mosasauroid (Upper Cretaceous, Hungary) and a New Clade of Basal Mosasauroids

    PubMed Central

    Makádi, László; Caldwell, Michael W.; Ősi, Attila

    2012-01-01

    Mosasauroids are conventionally conceived of as gigantic, obligatorily aquatic marine lizards (1000s of specimens from marine deposited rocks) with a cosmopolitan distribution in the Late Cretaceous (90–65 million years ago [mya]) oceans and seas of the world. Here we report on the fossilized remains of numerous individuals (small juveniles to large adults) of a new taxon, Pannoniasaurus inexpectatus gen. et sp. nov. from the Csehbánya Formation, Hungary (Santonian, Upper Cretaceous, 85.3–83.5 mya) that represent the first known mosasauroid that lived in freshwater environments. Previous to this find, only one specimen of a marine mosasauroid, cf. Plioplatecarpus sp., is known from non-marine rocks in Western Canada. Pannoniasaurus inexpectatus gen. et sp. nov. uniquely possesses a plesiomorphic pelvic anatomy, a non-mosasauroid but pontosaur-like tail osteology, possibly limbs like a terrestrial lizard, and a flattened, crocodile-like skull. Cladistic analysis reconstructs P. inexpectatus in a new clade of mosasauroids: (Pannoniasaurus (Tethysaurus (Yaguarasaurus, Russellosaurus))). P. inexpectatus is part of a mixed terrestrial and freshwater faunal assemblage that includes fishes, amphibians turtles, terrestrial lizards, crocodiles, pterosaurs, dinosaurs and birds. PMID:23284766

  6. Effect of seasonal changes on content and profile of soluble carbohydrates in tubers of different varieties of Jerusalem artichoke (Helianthus tuberosus L.).

    PubMed

    Kocsis, Laura; Liebhard, Peter; Praznik, Werner

    2007-11-14

    A high content (60-65% of dry mass DM) of water soluble carbohydrates was found in early harvested varieties (Bella and Bianka) and middle early varieties (Topstar and Gigant) harvested 22-25 weeks after plantation. In late varieties (Waldspindel, Violet de Rennes, Rote Zonenkugel) a similar amount was obtained (55-60% of DM) when harvested 29-33 weeks after planting. There was a distinctive impact on maturing process as well as frost period alterations which resulted in conversion of high polymer inulin to low polymer inulin as well as to sucrose. In early/middle early varieties a correlation between sucrose and inulin level (r = - 0.952**) with a linear regression of y = - 1.35x + 62.32 was observed, whereas the dpn of inulin decreased from 12-14 to 6-8. In late cultivars this correlation was not as exact (r = - 0.502**); dpn of inulin decreased from 12-16 to 7-10. This knowledge about carbohydrate profiles for different varieties of Jerusalem artichoke offers the possibility of selecting suitable cultivars and deciding the appropriate harvest time for an optimum processing of tubers for their application as prebiotic and novel food component. PMID:17941691

  7. Sale of US military aircraft to Saudi Arabia. Master`s thesis

    SciTech Connect

    Bents, E.R.

    1995-05-01

    The end of the Cold War in the late 1980s resulted in a gigantic downsizing and consolidation of America`s defense industries, as domestic demand plummeted and the volume of international arms trading fell. However, in total world arms exports the United States exports more arms than any other nation. The country of Saudi Arabia has been the destination of a disproportionate amount of these weapons. The following account is an examination of the US military aerospace industry, the world military aerospace market, US government policy concerning arms exports, and the Saudi aerospace market. Each of these entities profoundly impacts US-Saudi military aerospace commerce. By individually analyzing the above factors, it will be demonstrated that the supply relationship between the US and Saudi Arabia is dependent on the convergence of several long standing and deep seated aspirations on the part of the three major players: the US Aerospace Industry, the US Government, and the Saudi Government. The US military aerospace industry`s exports are critical to ensure its independent survival, help fund crucial RD programs, and maintain a viable defense high tech industrial base in the U.S. In addition, it wishes to exert a military presence in the Gulf area and nurture relations with Saudi Arabia in particular, as the world`s leading oil producer. The Saudi government requires a military defense anchored in high tech aerospace systems, as well as a dependable and capable military ally such as the US.

  8. Origin of marginal basins of the NW Pacific and their plate tectonic reconstructions

    NASA Astrophysics Data System (ADS)

    Xu, Junyuan; Ben-Avraham, Zvi; Kelty, Tom; Yu, Ho-Shing

    2014-03-01

    Geometry of basins can indicate their tectonic origin whether they are small or large. The basins of Bohai Gulf, South China Sea, East China Sea, Japan Sea, Andaman Sea, Okhotsk Sea and Bering Sea have typical geometry of dextral pull-apart. The Java, Makassar, Celebes and Sulu Seas basins together with grabens in Borneo also comprise a local dextral, transform-margin type basin system similar to the central and southern parts of the Shanxi Basin in geometry. The overall configuration of the Philippine Sea resembles a typical sinistral transpressional "pop-up" structure. These marginal basins except the Philippine Sea basin generally have similar (or compatible) rift history in the Cenozoic, but there do be some differences in the rifting history between major basins or their sub-basins due to local differences in tectonic settings. Rifting kinematics of each of these marginal basins can be explained by dextral pull-apart or transtension. These marginal basins except the Philippine Sea basin constitute a gigantic linked, dextral pull-apart basin system.

  9. Earth after the Moon-forming Impact

    NASA Astrophysics Data System (ADS)

    Zahnle, Kevin

    2006-09-01

    The Hadean Earth is widely and enduringly pictured as a world of exuberant volcanism, exploding meteors, huge craters, infernal heat, and billowing sulfurous steams; i.e., a world of fire and brimstone punctuated with blows to the head. In the background the Moon looms gigantic in the sky. The popular image has given it a name that celebrates our mythic roots. A hot early Earth is an inevitable consequence of accretion. The Moon-forming impact ensured that Earth as we know it emerged from a fog of silicate vapor. The impact separated the volatiles from the silicates. It took 100 years to condense and rain out the bulk of the vaporized silicates, although relatively volatile elements may have remained present in the atmosphere throughout the magma ocena stage. The magma ocean lasted 2 Myr, its lifetime prolonged by tidal heating and thermal blanketing by a thick CO2-rich steam atmosphere. Water oceans condensed quickly after the mantle solidified, but for some 10-100 Myr the surface would have stayed warm ( 500 K) until the CO2 was removed into the mantle. Thereafter the faint young Sun suggests that a lifeless Earth would always have been evolving toward a bitterly cold ice world, but the cooling trend was frequently interrupted by volcanic or impact induced thaws. This work was funded by NASA's Exobiology and Astrobiology Programs.

  10. Thermal Expansion Anomaly Regulated by Entropy

    PubMed Central

    Liu, Zi-Kui; Wang, Yi; Shang, ShunLi

    2014-01-01

    Thermal expansion, defined as the temperature dependence of volume under constant pressure, is a common phenomenon in nature and originates from anharmonic lattice dynamics. However, it has been poorly understood how thermal expansion can show anomalies such as colossal positive, zero, or negative thermal expansion (CPTE, ZTE, or NTE), especially in quantitative terms. Here we show that changes in configurational entropy due to metastable micro(scopic)states can lead to quantitative prediction of these anomalies. We integrate the Maxwell relation, statistic mechanics, and first-principles calculations to demonstrate that when the entropy is increased by pressure, NTE occurs such as in Invar alloy (Fe3Pt, for example), silicon, ice, and water, and when the entropy is decreased dramatically by pressure, CPTE is expected such as in anti-Invar cerium, ice and water. Our findings provide a theoretic framework to understand and predict a broad range of anomalies in nature in addition to thermal expansion, which may include gigantic electrocaloric and electromechanical responses, anomalously reduced thermal conductivity, and spin distributions. PMID:25391631

  11. A vision of the environmental and occupational noise pollution in Malaysia.

    PubMed

    Yuen, Foo Keng

    2014-01-01

    Environmental noise remains a complex and fragmented interplay between industrialization, population growth, technological developments, and the living environment. Next to the circulatory diseases and cancer, noise pollution has been cited as the third epidemic cause of psychological and physiological disorders internationally. A reliable and firm relationship between the cumulative health implications with the traffic annoyance and occupational noise has been established. This agenda has called for an integrated, coordinated, and participatory approach to the reliable protection of noise interference. Despite several fragmented policies, legislation and global efforts have been addressed; the noise pollution complaints have been traditionally neglected in developing countries, especially in Malaysia. This paper was undertaken to postulate an initial platform to address the dynamic pressures, gigantic challenges, and tremendous impacts of noise pollution scenario in Malaysia. The emphasis is speculated on the traffic interference and assessment of industrial and occupational noise. The fundamental importance of noise monitoring and modeling is proposed. Additionally, the confronting conservation program and control measure for noise pollution control are laconically elucidated. PMID:25387540

  12. Moa diet fits the bill: virtual reconstruction incorporating mummified remains and prediction of biomechanical performance in avian giants.

    PubMed

    Attard, Marie R G; Wilson, Laura A B; Worthy, Trevor H; Scofield, Paul; Johnston, Peter; Parr, William C H; Wroe, Stephen

    2016-01-13

    The moa (Dinornithiformes) are large to gigantic extinct terrestrial birds of New Zealand. Knowledge about niche partitioning, feeding mode and preference among moa species is limited, hampering palaeoecological reconstruction and evaluation of the impacts of their extinction on remnant native biota, or the viability of exotic species as proposed ecological 'surrogates'. Here we apply three-dimensional finite-element analysis to compare the biomechanical performance of skulls from five of the six moa genera, and two extant ratites, to predict the range of moa feeding behaviours relative to each other and to living relatives. Mechanical performance during biting was compared using simulations of the birds clipping twigs based on muscle reconstruction of mummified moa remains. Other simulated food acquisition strategies included lateral shaking, pullback and dorsoventral movement of the skull. We found evidence for limited overlap in biomechanical performance between the extant emu (Dromaius novaehollandiae) and extinct upland moa (Megalapteryx didinus) based on similarities in mandibular stress distribution in two loading cases, but overall our findings suggest that moa species exploited their habitats in different ways, relative to both each other and extant ratites. The broad range of feeding strategies used by moa, as inferred from interspecific differences in biomechanical performance of the skull, provides insight into mechanisms that facilitated high diversities of these avian herbivores in prehistoric New Zealand. PMID:26763698

  13. Magnetoelectric effect and magnetic phase diagram of a polar ferrimagnet CaBaFe4O7

    NASA Astrophysics Data System (ADS)

    Kocsis, V.; Tokunaga, Y.; Bordács, S.; Kriener, M.; Puri, A.; Zeitler, U.; Taguchi, Y.; Tokura, Y.; Kézsmárki, I.

    2016-01-01

    The magnetic phase diagram of a polar ferrimagnet CaBaFe4O7 with a magnetic easy axis has been investigated by measurements of magnetization, specific heat, and magnetoelectricity. A ferrimagnetic transition takes place at TC 1=275 K within the orthorhombic phase followed by a second magnetic transition at TC 2=211 K. Below TC 2, successive metamagnetic transitions occur for magnetic fields applied perpendicular to the easy axis, implying a sequential emergence of magnetic states which are neither collinear nor coplanar. The observation of the static magnetoelectric effect was limited to temperatures below 120 K due to the conducting nature of the crystals at higher temperatures. The magnitude of the ferroelectric polarization shows large changes between the different field-induced magnetic phases. The low-field state is characterized by a large linear magnetoelectric coefficient of αc c=39 ps/m, while a gigantic polarization change of Δ P =850 μ C /m2 is observed for μoH =14 T applied along the easy axis.

  14. Geological and geophysical evidence for a holocene tsunami deposit in the astern Mediterranean deep-sea record

    NASA Astrophysics Data System (ADS)

    Cita, Maria Bianca; Rimoldi, Bianca

    1997-09-01

    Extended geological and geophysical exploration of basinal settings in different areas of the eastern Mediterranean demonstrate the existence of a Holocene mud layer several metres in thickness (up to more than 20 m) and typically showing a graded basal part. The event producing this peculiar deposit is correlated with the gigantic 'Bronze Age' or Minoan eruption of the Santorini volcano (3500 years BP), which resulted in caldera collapse and supposedly produced a strong seismic sea-wave, that is a tsunami. Order of magnitude calculations demonstrate that the wave speed was sufficient to induce erosion and liquefaction of the soft unconsolidated sediments draping the deep-sea floor. The event is recorded in over 50 deep-sea cores recovered in the last 20 years which contain the fine grained 'Homogenite' layer starting with a fining-upwards sandy base and having a thickness of more than 24 m in the Sirte Abyssal Plain area. Several depositional models related to setting and source areas and based on thickness, composition, carbonate content and sedimentary structures of the deposits have been proposed.

  15. Aniakchak Crater, Alaska Peninsula

    USGS Publications Warehouse

    Smith, Walter R.

    1925-01-01

    The discovery of a gigantic crater northwest of Aniakchak Bay (see fig. 11) closes what had been thought to be a wide gap in the extensive series of volcanoes occurring at irregular intervals for nearly 600 miles along the axial line of the Alaska Peninsula and the Aleutian Islands. In this belt there are more active and recently active volcanoes than in all the rest of North America. Exclusive of those on the west side of Cook Inlet, which, however, belong to the same group, this belt contains at least 42 active or well-preserved volcanoes and about half as many mountains suspected or reported to be volcanoes. The locations of some of these mountains and the hot springs on the Alaska Peninsula and the Aleutian Islands are shown on a map prepared by G. A. Waring. Attention has been called to these volcanoes for nearly two centuries, but a record of their activity since the discovery of Alaska is far from being complete, and an adequate description of them as a group has never been written. Owing to their recent activity or unusual scenic beauty, some of the best known of the group are Mounts Katmai, Bogoslof, and Shishaldin, but there are many other beautiful and interesting cones and craters.

  16. What big eyes you have: the ecological role of giant pterygotid eurypterids

    PubMed Central

    Anderson, Ross P.; McCoy, Victoria E.; McNamara, Maria E.; Briggs, Derek E. G.

    2014-01-01

    Eurypterids are a group of extinct chelicerates that ranged for over 200 Myr from the Ordovician to the Permian. Gigantism is common in the group; about 50% of families include taxa over 0.8 m in length. Among these were the pterygotids (Pterygotidae), which reached lengths of over 2 m and were the largest arthropods that ever lived. They have been interpreted as highly mobile visual predators on the basis of their large size, enlarged, robust chelicerae and forward-facing compound eyes. Here, we test this interpretation by reconstructing the visual capability of Acutiramus cummingsi (Pterygotidae) and comparing it with that of the smaller Eurypterus sp. (Eurypteridae), which lacked enlarged chelicerae, and other arthropods of similar geologic age. In A. cummingsi, there is no area of lenses differentiated to provide increased visual acuity, and the interommatidial angles (IOA) do not fall within the range of high-level modern arthropod predators. Our results show that the visual acuity of A. cummingsi is poor compared with that of co-occurring Eurypterus sp. The ecological role of pterygotids may have been as predators on thin-shelled and soft-bodied prey, perhaps in low-light conditions or at night. PMID:25009243

  17. A Phororhacoid bird from the Eocene of Africa

    NASA Astrophysics Data System (ADS)

    Mourer-Chauviré, Cécile; Tabuce, Rodolphe; Mahboubi, M'hammed; Adaci, Mohammed; Bensalah, Mustapha

    2011-10-01

    The bird fossil record is globally scarce in Africa. The early Tertiary evolution of terrestrial birds is virtually unknown in that continent. Here, we report on a femur of a large terrestrial new genus discovered from the early or early middle Eocene (between ˜52 and 46 Ma) of south-western Algeria. This femur shows all the morphological features of the Phororhacoidea, the so-called Terror Birds. Most of the phororhacoids were indeed large, or even gigantic, flightless predators or scavengers with no close modern analogs. It is likely that this extinct group originated in South America, where they are known from the late Paleocene to the late Pleistocene (˜59 to 0.01 Ma). The presence of a phororhacoid bird in Africa cannot be explained by a vicariant mechanism because these birds first appeared in South America well after the onset of the mid-Cretaceous Gondwana break up (˜100 million years old). Here, we propose two hypotheses to account for this occurrence, either an early dispersal of small members of this group, which were still able of a limited flight, or a transoceanic migration of flightless birds from South America to Africa during the Paleocene or earliest Eocene. Paleogeographic reconstructions of the South Atlantic Ocean suggest the existence of several islands of considerable size between South America and Africa during the early Tertiary, which could have helped a transatlantic dispersal of phororhacoids.

  18. An innovative privacy preserving technique for incremental datasets on cloud computing.

    PubMed

    Aldeen, Yousra Abdul Alsahib S; Salleh, Mazleena; Aljeroudi, Yazan

    2016-08-01

    Cloud computing (CC) is a magnificent service-based delivery with gigantic computer processing power and data storage across connected communications channels. It imparted overwhelming technological impetus in the internet (web) mediated IT industry, where users can easily share private data for further analysis and mining. Furthermore, user affable CC services enable to deploy sundry applications economically. Meanwhile, simple data sharing impelled various phishing attacks and malware assisted security threats. Some privacy sensitive applications like health services on cloud that are built with several economic and operational benefits necessitate enhanced security. Thus, absolute cyberspace security and mitigation against phishing blitz became mandatory to protect overall data privacy. Typically, diverse applications datasets are anonymized with better privacy to owners without providing all secrecy requirements to the newly added records. Some proposed techniques emphasized this issue by re-anonymizing the datasets from the scratch. The utmost privacy protection over incremental datasets on CC is far from being achieved. Certainly, the distribution of huge datasets volume across multiple storage nodes limits the privacy preservation. In this view, we propose a new anonymization technique to attain better privacy protection with high data utility over distributed and incremental datasets on CC. The proficiency of data privacy preservation and improved confidentiality requirements is demonstrated through performance evaluation. PMID:27369566

  19. History of rocketry in India

    NASA Astrophysics Data System (ADS)

    Vasant, Gowarikar; Suresh, B. N.

    2009-12-01

    The Indian Space programme took birth on November 21, 1963, with the launch of Nike-Apache, an American sounding rocket from the shores of Thumba near Thiruvananthapuram on the west coast of India. From a family of operational sounding rockets known as the Rohini Sounding Rockets, India's launch vehicles have now grown up through SLV-3 and Augmented Satellite Launch Vehicle (ASLV) to the current gigantic satellite launchers, PSLV and Geosynchronous Satellite Launch Vehicle (GSLV). Though we had failures in the initial launches of SLV-3, ASLV and PSLV, these failures gave Indian Space Research Organisation (ISRO) a thorough and in depth understanding of the nuances of launch vehicle technology that later led to successful missions. An entirely new dimension was added to the Indian space programme when a space capsule was recovered very precisely after it had orbited the Earth for 12 days. The future for launch vehicles in ISRO looks bright with the GSLV MKIII, which is currently under development and the pursuit of cutting edge technologies such as reusable launch vehicles and air-breathing propulsion.

  20. [Postnatal skeletal and body weight in beagles].

    PubMed

    Salomon, F V; Schulze, A; Böhme, U; Arnold, U; Gericke, A; Gille, U

    1999-08-01

    Growth of beagles is described on the basis of body weight and 14 bone measures. Eighteen male and 19 female dogs were investigated at 14 different ages from birth to the 13th month of life. Characteristics of the growth curves were evaluated using the modified Janoschek growth curve. For the classification into dwarfish, low, normal, big and gigantic growth, the growth curves are presented with percentiles. The arithmetic means and standard deviations for both sexes are presented in tables. Additionally, the degrees of maturity at birth (relative proportion of final weight or bone measure), the point of inflection for the growth curve, the times to grow to 50 and 95% of the final measures, and the asymptotic measures are also presented in tables. Sex differences in growth for the body weight and bone measures are discussed. Growth differences between large and small dog breeds are considered. The conclusion is drawn that the feeding of dogs has to be adapted to the growth course. PMID:10488625

  1. From the Cover: Environmental and biotic controls on the evolutionary history of insect body size

    NASA Astrophysics Data System (ADS)

    Clapham, Matthew E.; Karr, Jered A.

    2012-07-01

    Giant insects, with wingspans as large as 70 cm, ruled the Carboniferous and Permian skies. Gigantism has been linked to hyperoxic conditions because oxygen concentration is a key physiological control on body size, particularly in groups like flying insects that have high metabolic oxygen demands. Here we show, using a dataset of more than 10,500 fossil insect wing lengths, that size tracked atmospheric oxygen concentrations only for the first 150 Myr of insect evolution. The data are best explained by a model relating maximum size to atmospheric environmental oxygen concentration (pO2) until the end of the Jurassic, and then at constant sizes, independent of oxygen fluctuations, during the Cretaceous and, at a smaller size, the Cenozoic. Maximum insect size decreased even as atmospheric pO2 rose in the Early Cretaceous following the evolution and radiation of early birds, particularly as birds acquired adaptations that allowed more agile flight. A further decrease in maximum size during the Cenozoic may relate to the evolution of bats, the Cretaceous mass extinction, or further specialization of flying birds. The decoupling of insect size and atmospheric pO2 coincident with the radiation of birds suggests that biotic interactions, such as predation and competition, superseded oxygen as the most important constraint on maximum body size of the largest insects.

  2. Interplay between superconductivity and magnetism in Fe1−xPdxTe

    PubMed Central

    Karki, Amar B.; Garlea, V. Ovidiu; Custelcean, Radu; Stadler, Shane; Plummer, E. W.; Jin, Rongying

    2013-01-01

    The attractive/repulsive relationship between superconductivity and magnetic ordering has fascinated the condensed matter physics community for a century. In the early days, magnetic impurities doped into a superconductor were found to quickly suppress superconductivity. Later, a variety of systems, such as cuprates, heavy fermions, and Fe pnictides, showed superconductivity in a narrow region near the border to antiferromagnetism (AFM) as a function of pressure or doping. However, the coexistence of superconductivity and ferromagnetic (FM) or AFM ordering is found in a few compounds [RRh4B4 (R = Nd, Sm, Tm, Er), R′Mo6X8 (R′ = Tb, Dy, Er, Ho, and X = S, Se), UMGe (M = Ge, Rh, Co), CeCoIn5, EuFe2(As1−xPx)2, etc.], providing evidence for their compatibility. Here, we present a third situation, where superconductivity coexists with FM and near the border of AFM in Fe1−xPdxTe. The doping of Pd for Fe gradually suppresses the first-order AFM ordering at temperature TN/S, and turns into short-range AFM correlation with a characteristic peak in magnetic susceptibility at T′N. Superconductivity sets in when T′N reaches zero. However, there is a gigantic ferromagnetic dome imposed in the superconducting-AFM (short-range) cross-over regime. Such a system is ideal for studying the interplay between superconductivity and two types of magnetic (FM and AFM) interactions. PMID:23690601

  3. A High-velocity Cloud Impact Forming a Supershell in the Milky Way

    NASA Astrophysics Data System (ADS)

    Park, Geumsook; Koo, Bon-Chul; Kang, Ji-hyun; Gibson, Steven J.; Peek, J. E. G.; Douglas, Kevin A.; Korpela, Eric J.; Heiles, Carl E.

    2016-08-01

    Neutral atomic hydrogen (H i) gas in interstellar space is largely organized into filaments, loops, and shells, the most prominent of which are “supershells.” These gigantic structures, which require ≳ 3× {10}52 erg to form, are generally thought to be produced by either the explosion of multiple supernovae (SNe) in OB associations or, alternatively, by the impact of high-velocity clouds (HVCs) falling into the Galactic disk. Here, we report the detection of a kiloparsec (kpc)-size supershell in the outskirts of the Milky Way with the compact HVC 040 + 01‑282 (hereafter, CHVC040) at its geometrical center using the “Inner-Galaxy Arecibo L-band Feed Array” H i 21 cm survey data. The morphological and physical properties of both objects suggest that CHVC040, which is either a fragment of a nearby disrupted galaxy or a cloud that originated from an intergalactic accreting flow, collided with the disk ∼5 Myr ago to form the supershell. Our results show that some compact HVCs can survive their trip through the Galactic halo and inject energy and momentum into the Milky Way disk.

  4. 3D reconstruction of the source and scale of buried young flood channels on Mars.

    PubMed

    Morgan, Gareth A; Campbell, Bruce A; Carter, Lynn M; Plaut, Jeffrey J; Phillips, Roger J

    2013-05-01

    Outflow channels on Mars are interpreted as the product of gigantic floods due to the catastrophic eruption of groundwater that may also have initiated episodes of climate change. Marte Vallis, the largest of the young martian outflow channels (<500 million years old), is embayed by lava flows that hinder detailed studies and comparisons with older channel systems. Understanding Marte Vallis is essential to our assessment of recent Mars hydrologic activity during a period otherwise considered to be cold and dry. Using data from the Shallow Radar sounder on the Mars Reconnaissance Orbiter, we present a three-dimensional (3D) reconstruction of buried channels on Mars and provide estimates of paleohydrologic parameters. Our work shows that Cerberus Fossae provided the waters that carved Marte Vallis, and it extended an additional 180 kilometers to the east before the emplacement of the younger lava flows. We identified two stages of channel incision and determined that channel depths were more than twice those of previous estimates. PMID:23470730

  5. Expression of parasite genetic variation changes over the course of infection: implications of within-host dynamics for the evolution of virulence

    PubMed Central

    Clerc, Melanie; Ebert, Dieter; Hall, Matthew D.

    2015-01-01

    How infectious disease agents interact with their host changes during the course of infection and can alter the expression of disease-related traits. Yet by measuring parasite life-history traits at one or few moments during infection, studies have overlooked the impact of variable parasite growth trajectories on disease evolution. Here we show that infection-age-specific estimates of host and parasite fitness components can reveal new insight into the evolution of parasites. We do so by characterizing the within-host dynamics over an entire infection period for five genotypes of the castrating bacterial parasite Pasteuria ramosa infecting the crustacean Daphnia magna. Our results reveal that genetic variation for parasite-induced gigantism, host castration and parasite spore loads increases with the age of infection. Driving these patterns appears to be variation in how well the parasite maintains control of host reproduction late in the infection process. We discuss the evolutionary consequences of this finding with regard to natural selection acting on different ages of infection and the mechanism underlying the maintenance of castration efficiency. Our results highlight how elucidating within-host dynamics can shed light on the selective forces that shape infection strategies and the evolution of virulence. PMID:25761710

  6. Practical assay for nitrite and nitrosothiol as an alternative to the Griess assay or the 2,3-diaminonaphthalene assay.

    PubMed

    Shen, Yanming; Zhang, Quanjuan; Qian, Xuhong; Yang, Youjun

    2015-01-20

    Nitrite is a heavily assayed substrate in the fields of food safety, water quality control, disease diagnosis, and forensic investigation and more recently in basic biological studies on nitric oxide physiology and pathology. The colorimetric Griess assay and the fluorimetric 2,3-diaminonaphthalene (DAN) assay are the current gold standards for nitrite quantification. They are not without limitations, yet have amazingly survived 156 and 44 years, respectively, due to the lack of a practical alternative. Both assays exhibit slow detection kinetics due to inactivation of nucleophiles under strongly acidic media, require an extensive incubation time for reaction to go completion, and hence offer a limited detection throughput. By converting an intermolecular reaction of the Griess assay intramolecularly, we designed a novel probe (NT555) for nitrite detection, which displays superior detection kinetics and sensitivity. NT555 was constructed following our "covalent-assembly" probe design principle. Upon detection, it affords a gigantic bathochromic shift of the absorption spectrum and a sensitive turn-on fluorescence signal from a zero background, both of which are typical of an "assembly" type probe. Overall, NT555 has addressed various difficulties associated with the Griess and the DAN assays and represents an attractive alternative for practical applications. PMID:25519711

  7. Similarity analysis of the streamer zone of Blue jets

    NASA Astrophysics Data System (ADS)

    Popov, N. A.; Shneider, M. N.; Milikh, G. M.

    2016-09-01

    Multiple observations of Blue Jets (BJ) and Gigantic Blue Jets (GBJ) show that BJ and GBJ emits a fan of streamers similar to a laboratory leader. Moreover, in the exponential atmosphere those long streamers grow preferentially upward, producing a narrow cone confined by the aperture angle. It was also noticed that BJ are similar to the streamer zone of a leader (streamer corona) and the modeling studies based on the streamers fractal structure were conducted. Objective of this paper is to study the fractal dimension of the bunch of streamer channels emitted by BJ and GBJ, at different altitude and under the varying electric field. This similarity analysis has been done in three steps: first we described the dendritic structure of streamers in corona discharge applying the fractal theory. Then using this model and the data from existing laboratory experiments we obtained the fractal dimension of the branching streamer channels. Finally the model was validated by the observations of BJ available from the literature.

  8. The Associated Sferics of the ISUAL Blue Luminous Events

    NASA Astrophysics Data System (ADS)

    Chou, J. K.; Hsu, R. R.; Su, H. T.; Chen, A. B. C.; Kuo, C. L.; Huang, S. M.; Chang, S. C.; Wu, Y. J.; Kang-Ming, P.; Frey, H. U.; Takahashi, Y.; Lee, L. C.

    2015-12-01

    ISUAL has recorded many mystic blue luminous events (BLEs) that emit clear middle ultraviolet to blue emissions (230-450 nm) but contain dim red emissions (653-754 nm). Most BLEs appear to be dot-like on the ISUAL images, and a few BLEs develop further into blue jets or type II gigantic jets (GJs). The associated sferics of the BLEs in the extremely low frequency to the very low frequency (ELF/VLF) band and the low frequency (LF) band exhibit similar features to those of the VLF/LF waveform for the narrow bipolar events (NBEs). The ISUAL BLE is conjectured to be the accompanied light emissions from the NBE-like event. Both positive and negative discharge polarity-types for the BLEs have been found. Based on the sferics and the ISUAL optical data, a NBE-like event is found to be related to a rapidly-flowing current of the initiation discharge in the thunderstorm, while a blue jet or a type II GJ is suggested to be associated with the slowly-varying current of the ensuing discharge. The selected six blue jets and one type II GJ occurring within 3,500 km from the NCKU sferics-detecting stations are inferred to be positive upward discharges. The spectral characteristics of BLEs resemble those of the emissions mostly from the non-thermal air plasmas produced by the locally-enhanced electric field, rather than those from the hot air plasmas in local thermodynamic equilibrium (LTE).

  9. Discharges in the Stratosphere and Mesosphere

    NASA Astrophysics Data System (ADS)

    Siingh, Devendraa; Singh, R. P.; Singh, Ashok K.; Kumar, Sanjay; Kulkarni, M. N.; Singh, Abhay K.

    2012-09-01

    In the present paper salient features of discharges in the stratosphere and mesosphere (namely sprites, halos, blue starters, blue jets, gigantic jets and elves), are discussed. The electrostatic field due to charge imbalance during lightning processes may lead to stratospheric/mesospheric discharges either through the conventional breakdown based on streamers and leaders or relativistic runaway mechanism. Most (not all) of the observed features of sprites, halos and jets are explained by this processes. Development and evolution of streamers are based on the local transient electrostatic field and available ambient electron density which dictate better probability in favor of positive cloud-to-ground discharges, and thus explains the polarity asymmetry in triggering sprites and streamers. Elves are generated by electromagnetic pulse radiated by return stroke currents of cloud-to-ground/inter-cloud discharges. Generation of the both donut and pancake shape elves are explained. Electrodynamic features of thunderstorms associated with stratospheric/mesospheric discharges are summarized including current and charge moment associated with relevant cloud-to-ground discharges. The hypothesis relating tropospheric generated gravity waves and mesospheric discharges are also discussed. Finally some interesting problems are listed.

  10. New tyrannosaur from the mid-Cretaceous of Uzbekistan clarifies evolution of giant body sizes and advanced senses in tyrant dinosaurs

    NASA Astrophysics Data System (ADS)

    Brusatte, Stephen L.; Averianov, Alexander; Sues, Hans-Dieter; Muir, Amy; Butler, Ian B.

    2016-03-01

    Tyrannosaurids—the familiar group of carnivorous dinosaurs including Tyrannosaurus and Albertosaurus—were the apex predators in continental ecosystems in Asia and North America during the latest Cretaceous (ca. 80-66 million years ago). Their colossal sizes and keen senses are considered key to their evolutionary and ecological success, but little is known about how these features developed as tyrannosaurids evolved from smaller basal tyrannosauroids that first appeared in the fossil record in the Middle Jurassic (ca. 170 million years ago). This is largely because of a frustrating 20+ million-year gap in the mid-Cretaceous fossil record, when tyrannosauroids transitioned from small-bodied hunters to gigantic apex predators but from which no diagnostic specimens are known. We describe the first distinct tyrannosauroid species from this gap, based on a highly derived braincase and a variety of other skeletal elements from the Turonian (ca. 90-92 million years ago) of Uzbekistan. This taxon is phylogenetically intermediate between the oldest basal tyrannosauroids and the latest Cretaceous forms. It had yet to develop the giant size and extensive cranial pneumaticity of T. rex and kin but does possess the highly derived brain and inner ear characteristic of the latest Cretaceous species. Tyrannosauroids apparently developed huge size rapidly during the latest Cretaceous, and their success in the top predator role may have been enabled by their brain and keen senses that first evolved at smaller body size.

  11. Energy and globalization

    NASA Astrophysics Data System (ADS)

    Birjandi, Hossein Saremi

    Before the Industrial Revolution, nations required no energy fuel. People relied on human, animal, and wind and waterpower for energy need. Energy (oil) has resettled populations, elected officials in the free world, or changed the governments of the energy rich countries by force. Energy fueled wars, played the major factor in the might of those who have it or more importantly the abilities to acquire it by force. This dissertation researches the primacy of oil as an energy source from the time of oil's discovery to the present times. Between 1945 and 1960, the use of oil and gas doubled as power was generated for industries as steel, cement, metalworking and more important of all filling station hoses into automobiles gas tanks, thus energy swept people and societies quite literally off their feet. One in every six jobs in the industrial world hired by the giant automotive industries. The big five American oil companies spurred on by special tax benefit, these companies grew to gigantic sizes by taking out the best part of the nation's oil. Then, for greater growth, they leaped overseas and built up an immensely profitable system, in alliance with Anglo-Dutch Shell and British Petroleum, known as seven sisters. On the other side of the world, the energy producing nations form an alliance mainly to protect themselves from downward price fluctuations of oil. The struggle for survival in the global energy market forced those countries to get together and form OPEC, which is referred as an "oil cartel".

  12. The potential of THEMIS satellite and ground-based measurements for data mining

    NASA Astrophysics Data System (ADS)

    Frey, S.; Angelopoulos, V.; Sibeck, D. G.; Phan, T.; Eastwood, J. P.; Runov, A.; Frey, H. U.

    2009-12-01

    Launched on February 17, 2007 on a DELTA II rocket, NASA's Time History of Events and Macroscale Interactions during Substorms (THEMIS) mission is a Medium-class Explorer project and the first space mission to study the sequence of magnetospheric events that trigger gigantic auroral displays in the polar regions using a macro-scale constellation of spacecraft. THEMIS is composed of a space segment of 5 identical probes equipped with particle and field instruments and a ground segment of about 20 Ground-Based Observatories with all-sky cameras and magnetometers. During its nominal mission THEMIS has observed over 20 substorm events, measured radial profiles of high energy particles through the radiation belts year-round, and provided numerous multi-point measurements across the magnetopause and bow shock with upstream monitoring. THEMIS data as well as the methods developed to simultaneously detect magnetospheric processes or structures are ideal for the development of software tools to efficiently extract data. We will present the potential of the THEMIS data to catalog magnetospheric events, define search patterns for event detection as well standardized interfaces with models.

  13. Evaluation of the antiplasmodial and cytotoxicity potentials of husk fiber extracts from Cocos nucifera, a medicinal plant used in Nigeria to treat human malaria.

    PubMed

    Adebayo, J O; Santana, A E G; Krettli, A U

    2012-03-01

    Nigeria is an African country where transmission of malaria occurs all year round and where most inhabitants use plants as remedies against parasitic diseases, including malaria. Some of such medicinal plants have their antimalarial efficacies already demonstrated experimentally, active compounds isolated and the mechanism of drug action suggested. Decoction of Cocos nucifera husk is used in the middle belt region of Nigeria as an antimalarial remedy. In our current studies, we tested extracts from husks of four varieties of C. nucifera, all collected in Brazil, where the plant fruit is popularly named 'coco'. The husks of coco mestiço, amarelo, anão and gigante collected in the Northeast of Brazil were used to prepare extracts at the Chemistry Department, Federal University of Alagoas (UFAL), which were then tested for their antiplasmodial activities, cytotoxicities and hemolytic activities in vitro. Only the hexane extract of coco mestiço was active against the blood forms of Plasmodium falciparum human malaria parasite maintained in continuous culture. Most extracts presented selectivity indices of <10, while hexane extract of coco mestiço had a selectivity index of 35, meaning that the extract is not toxic. The isolation of the active compounds from coco mestiço husks has not yet been done. PMID:22241625

  14. Peculiar macrophagous adaptations in a new Cretaceous pliosaurid

    PubMed Central

    Arkhangelsky, Maxim S.; Stenshin, Ilya M.; Uspensky, Gleb N.; Zverkov, Nikolay G.

    2015-01-01

    During the Middle and Late Jurassic, pliosaurid plesiosaurs evolved gigantic body size and a series of craniodental adaptations that have been linked to the occupation of an apex predator niche. Cretaceous pliosaurids (i.e. Brachaucheninae) depart from this morphology, being slightly smaller and lacking the macrophagous adaptations seen in earlier forms. However, the fossil record of Early Cretaceous pliosaurids is poor, concealing the evolution and ecological diversity of the group. Here, we report a new pliosaurid from the Late Hauterivian (Early Cretaceous) of Russia. Phylogenetic analyses using reduced consensus methods recover it as the basalmost brachauchenine. This pliosaurid is smaller than other derived pliosaurids, has tooth alveoli clustered in pairs and possesses trihedral teeth with complex serrated carinae. Maximum-likelihood ancestral state reconstruction suggests early brachauchenines retained trihedral teeth from their ancestors, but modified this feature in a unique way, convergent with macrophagous archosaurs or sphenacodontoids. Our findings indicate that Early Cretaceous marine reptile teeth with serrated carinae cannot be unequivocally assigned to metriorhynchoid crocodylomorphs. Furthermore, they extend the known diversity of dental adaptations seen in Sauropterygia, the longest lived clade of marine tetrapods. PMID:27019740

  15. Interpretation of the Jupiter Red Spot, 1

    NASA Technical Reports Server (NTRS)

    Kuiper, G. P.

    1973-01-01

    With the aid of 8900 micron CH4 filter photographs it is shown that the Red Spot is normally the highest cloud feature in the Jovian atmosphere, located squarely on the South Tropical Zone at 22 deg. S. The Red Spot is a rising column, obviously having its own energy source; it spreads outward at the top level, in anticyclonic rotation. It is concluded that the large and persistent Jovian cloud masses, of which the Red Spot is the largest, are major organized storm arrays embedded in a near stagnant atmosphere, each probably possessing numerous short-lived rising hot columns driven by released latent heat; and covered by a horizontally-expanding gigantic cirrus cloud system, in anti-cyclonic rotation. The meteorological theory of Organized Cumulus Convection is applied to the Red Spot and the White Ovals. Evidence exists that the array of hot towers under the Red Spot is eccentric. The 90-day and the occassional 5-8 year fluctuations in the motion of the Red Spot may be due to processes analogous to those found in the Earth's Tropical Convergence. The 90-day oscillation has been observed for 8 years.

  16. Was there a super-eruption on the Gondwanan coast 477 Ma ago?

    NASA Astrophysics Data System (ADS)

    Gutiérrez-Alonso, G.; Gutiérrez-Marco, J. C.; Fernández-Suárez, J.; Bernárdez, E.; Corfu, F.

    2016-06-01

    Precise zircon and monazite ID-TIMS U-Pb dating of three Lower Ordovician altered ash-fall tuff beds (K-bentonites) in the Cantabrian Zone of NW Iberia yielded coeval ages together with an equivalent previously studied sample (477.5 ± 1 (Gutierrez-Alonso et al., 2007)), of 477 ± 1.3 Ma, 477.2 ± 1.1 Ma and 477.3 ± 1 Ma, with a pooled concordia age (all analyses in the four samples) of 477.2 ± 0.74 Ma. A conservative estimation of the volume and mass of the studied K-bentonite beds (using exclusively the CZ data) yields a volume for the preserved deposits of ca. 37.5 km3 (Volcanic Explosivity Index - VEI = 6, Colossal). When considering other putative equivalent beds in Iberia and neighboring realms (i.e. Armorica, Sardinia) the volume of ejecta associated to this event would make it reach the Supervolcanic-Apocalyptic status (VEI = 8, > 1000 km3). At variance with most known cases of this kind of gigantic eruption events, geological observations indicate that the studied magmatic event was related to continental margin extension and thinning and not to plate convergence. We speculate that a geochronologically equivalent large caldera event recognized in the geological record of NW Iberia could be ground zero of this super-eruption.

  17. Mutation Update: The Spectra of Nebulin Variants and Associated Myopathies

    PubMed Central

    Lehtokari, Vilma-Lotta; Kiiski, Kirsi; Sandaradura, Sarah A.; Laporte, Jocelyn; Repo, Pauliina; Frey, Jennifer A.; Donner, Kati; Marttila, Minttu; Saunders, Carol; Barth, Peter G.; den Dunnen, Johan T.; Beggs, Alan H.; Clarke, Nigel F.; North, Kathryn N.; Laing, Nigel G.; Romero, Norma B.; Winder, Thomas L.; Pelin, Katarina; Wallgren-Pettersson, Carina

    2015-01-01

    A mutation update on the nebulin gene (NEB) is necessary because of recent developments in analysis methodology, the identification of increasing numbers and novel types of variants, and a widening in the spectrum of clinical and histological phenotypes associated with this gigantic, 183 exons containing gene. Recessive pathogenic variants in NEB are the major cause of nemaline myopathy (NM), one of the most common congenital myopathies. Moreover, pathogenic NEB variants have been identified in core-rod myopathy and in distal myopathies. In this update, we present the disease-causing variants in NEB in 159 families, 143 families with NM, and 16 families with NM-related myopathies. Eighty-eight families are presented here for the first time. We summarize 86 previously published and 126 unpublished variants identified in NEB. Furthermore, we have analyzed the NEB variants deposited in the Exome Variant Server (http://evs.gs.washington.edu/EVS/), identifying that pathogenic variants are a minor fraction of all coding variants (~7%). This indicates that nebulin tolerates substantial changes in its amino acid sequence, providing an explanation as to why variants in such a large gene result in relatively rare disorders. Lastly, we discuss the difficulties of drawing reliable genotype–phenotype correlations in NEB-associated disease. PMID:25205138

  18. Statistical characteristics of seismo-ionospheric GPS TEC disturbances prior to global Mw ≥ 5.0 earthquakes (1998-2014)

    NASA Astrophysics Data System (ADS)

    Shah, Munawar; Jin, Shuanggen

    2015-12-01

    Pre-earthquake ionospheric anomalies are still challenging and unclear to obtain and understand, particularly for different earthquake magnitudes and focal depths as well as types of fault. In this paper, the seismo-ionospheric disturbances (SID) related to global earthquakes with 1492 Mw ≥ 5.0 from 1998 to 2014 are investigated using the total electron content (TEC) of GPS global ionosphere maps (GIM). Statistical analysis of 10-day TEC data before global Mw ≥ 5.0 earthquakes shows significant enhancement 5 days before an earthquake of Mw ≥ 6.0 at a 95% confidence level. Earthquakes with a focal depth of less than 60 km and Mw ≥ 6.0 are presumably the root of deviation in the ionospheric TEC because earthquake breeding zones have gigantic quantities of energy at shallower focal depths. Increased anomalous TEC is recorded in cumulative percentages beyond Mw = 5.5. Sharpness in cumulative percentages is evident in seismo-ionospheric disturbance prior to Mw ≥ 6.0 earthquakes. Seismo-ionospheric disturbances related to strike slip and thrust earthquakes are noticeable for magnitude Mw6.0-7.0 earthquakes. The relative values reveal high ratios (up to 2) and low ratios (up to -0.5) within 5 days prior to global earthquakes for positive and negative anomalies. The anomalous patterns in TEC related to earthquakes are possibly due to the coupling of high amounts of energy from earthquake breeding zones of higher magnitude and shallower focal depth.

  19. On heavy dustfall observed with explosive sandstorms in Chongwon-Chongju, Korea in 2002

    NASA Astrophysics Data System (ADS)

    Chung, Yong-seung; Kim, Hak-sung; Dulam, Jugder; Harris, Joyce

    Continuous monitoring of sand and duststorms (SD) and associated heavy dustfall (HD) is made in Korea. In particular, accurate measurements of atmospheric dust loadings have been carried out with the tapered element oscillating microbalance method, and satellite detection of dust clouds is included in the analysis. In 2002, we found three gigantic dust clouds that moved over the Korean Peninsula, and associated HD occurred with PM10 values of 1106-3006 μg m -3. In Beijing, China much higher concentrations were recorded, while in SW Japan measured values were up to 986 μg m -3. Two SD occurred in March and April, while the third one occurred unusually in November. During the year, there were nine cases of reddish-brown sand with 18 dusty days. The intensity of HD was extraordinary for the recent decade. It was observed that with invading SD, the higher the PM10 values the lower the PM2.5 loadings. Also, variations of visibility were more depending on PM2.5 variations than PM10 values. It is shown that satellite detection is a useful technique in monitoring SD and HD.

  20. [The Sotos syndrome. Clinical and neuropsychiatric considerations in 1 case].

    PubMed

    Trizio, M; Intino, M T; Lanzi, C; Krajewska, G; Perniola, T

    1983-01-01

    A case of Sotos' syndrome or cerebral gigantism is described. The main clinical features of this syndrome are macrocrania, accelerated skeleton maturation and somatic development, cranio-facial dysmorfism, psychomotor retardation in 80% of the cases. Less frequently other skeleton abnormalities associated with neurological and/or endocrinological disorders are reported. In our patient the typical features of the syndrome are accompanied by several neurological signs (mental retardtion, strabism, hypothonia, motor impairment, seizures, CT scan abnormalities) and ophtalmological changes as optic disk pallor. The above mentioned range of symptoms should be considered as a direct consequence of the primary defect which characterizes the Sotos' syndrome. In our case the cerebral nervous system seems to be more specifically involved. Besides, important behavioural difficulties have emerged with regard to the double relation mother-daughter and in the familiar environment as well. For this reason we emphasize the necessity of evaluating and clearing up all problems which often arise in connection with various pathological conditions in childhood. This should be done in order to grant the families an appropriate support. PMID:6680796

  1. Interplay between Superconductivity and Magnetism in Fe1-xPdxTe

    SciTech Connect

    Karki, A B; Garlea, Vasile O; Custelcean, Radu; Stadler, S.; Plummer, E. W.; Jin, Rongying

    2013-01-01

    The love/hate relationship between superconductivity and magnetic ordering has fascinated the condensed matter physics community for a century. In the early days, magnetic impurities doped into a superconductor were found to quickly suppress superconductivity. Later, a variety of systems, such as cuprates, heavy fermions and Fe pnictides, show superconductivity in a narrow region near the border to antiferromagnetism (AFM) as a function of pressure or doping. On the other hand, the coexistence of superconductivity and ferromagnetic (FM) or AFM ordering is found in a few compounds (RRh4B4 (R = Nd, Sm, Tm, Er), R'Mo6X8 (R' = Tb, Dy, Er, Ho, and X = S, Se), UMGe (M = Ge, Rh, Co), CeCoIn5, EuFe2(As1-xPx)2 etc.), providing evidence for their compatibility. Here, we present a third situation, where superconductivity coexists with FM and near the border of AFM in Fe1-xPdxTe. The doping of Pd for Fe gradually suppresses the first-order AFM ordering at temperature TN/S, and turns into short-range (SR) AFM correlation with a characteristic peak in magnetic susceptibility at T'N. Superconductivity sets in when T'N reaches zero. However, there is a gigantic ferromagnetic dome imposed in the superconducting-AFM (SR) crossover regime. Such a system is ideal for studying the interplay between superconductivity and two types of magnetic interactions (FM and AFM).

  2. Giant lizards occupied herbivorous mammalian ecospace during the Paleogene greenhouse in Southeast Asia.

    PubMed

    Head, Jason J; Gunnell, Gregg F; Holroyd, Patricia A; Hutchison, J Howard; Ciochon, Russell L

    2013-07-22

    Mammals dominate modern terrestrial herbivore ecosystems, whereas extant herbivorous reptiles are limited in diversity and body size. The evolution of reptile herbivory and its relationship to mammalian diversification is poorly understood with respect to climate and the roles of predation pressure and competition for food resources. Here, we describe a giant fossil acrodontan lizard recovered with a diverse mammal assemblage from the late middle Eocene Pondaung Formation of Myanmar, which provides a historical test of factors controlling body size in herbivorous squamates. We infer a predominately herbivorous feeding ecology for the new acrodontan based on dental anatomy, phylogenetic relationships and body size. Ranking body masses for Pondaung Formation vertebrates indicates that the lizard occupied a size niche among the larger herbivores and was larger than most carnivorous mammals. Paleotemperature estimates of Pondaung Formation environments based on the body size of the new lizard are approximately 2-5°C higher than modern. These results indicate that competitive exclusion and predation by mammals did not restrict body size evolution in these herbivorous squamates, and elevated temperatures relative to modern climates during the Paleogene greenhouse may have resulted in the evolution of gigantism through elevated poikilothermic metabolic rates and in response to increases in floral productivity. PMID:23740779

  3. Fusion: A true challenge for an enormous reward

    NASA Astrophysics Data System (ADS)

    Ongena, J.

    2015-08-01

    From nuclear physics we know that energy can be released not only from the fission of heavy nuclei but also from the fusion of light nuclei. Steady progress shows that fusion—one of the few possible options for the future—can be a clean and safe solution for mankind's long-term energy needs, with minimal environmental impact. A source of energy which would be inexhaustible, inherently safe and environmentally friendly, is this not a marvellous prospect? Nuclear fusion has been the energy source of our Sun and the stars in the universe for billions of years. This process requires temperatures of tens of millions of degrees, so extremely high and foreign to our daily experience as to seem out of reach. Nevertheless, these extremely high temperatures are routinely realised in several laboratories all over the world, and since the early 1990s, large amounts of energy have been released in a controlled way from fusion reactions. We are witnessing the birth of a new technology destined to meet the gigantic future energy needs of mankind with minimal impact on the environment.

  4. Overview of laser-driven generation of electron-positron beams

    NASA Astrophysics Data System (ADS)

    Sarri, G.; Dieckmann, M. E.; Kourakis, I.; di Piazza, A.; Reville, B.; Keitel, C. H.; Zepf, M.

    2015-08-01

    Electron-positron (e-p) plasmas are widely thought to be emitted, in the form of ultra-relativistic winds or collimated jets, by some of the most energetic or powerful objects in the Universe, such as black-holes, pulsars, and quasars. These phenomena represent an unmatched astrophysical laboratory to test physics at its limit and, given their immense distance from Earth (some even farther than several billion light years), they also provide a unique window on the very early stages of our Universe. However, due to such gigantic distances, their properties are only inferred from the indirect interpretation of their radiative signatures and from matching numerical models: their generation mechanism and dynamics still pose complicated enigmas to the scientific community. Small-scale reproductions in the laboratory would represent a fundamental step towards a deeper understanding of this exotic state of matter. Here we present recent experimental results concerning the laser-driven production of ultra-relativistic e-p beams. In particular, we focus on the possibility of generating beams that present charge neutrality and that allow for collective effects in their dynamics, necessary ingredients for the testing pair-plasma physics in the laboratory. A brief discussion of the analytical and numerical modelling of the dynamics of these plasmas is also presented in order to provide a summary of the novel plasma physics that can be accessed with these objects. Finally, general considerations on the scalability of laboratory plasmas up to astrophysical scenarios are given.

  5. Baleen boom and bust: a synthesis of mysticete phylogeny, diversity and disparity

    PubMed Central

    Marx, Felix G.; Fordyce, R. Ewan

    2015-01-01

    A new, fully dated total-evidence phylogeny of baleen whales (Mysticeti) shows that evolutionary phases correlate strongly with Caenozoic modernization of the oceans and climates, implying a major role for bottom-up physical drivers. The phylogeny of 90 modern and dated fossil species suggests three major phases in baleen whale history: an early adaptive radiation (36–30 Ma), a shift towards bulk filter-feeding (30–23 Ma) and a climate-driven diversity loss around 3 Ma. Evolutionary rates and disparity were high following the origin of mysticetes around 38 Ma, coincident with global cooling, abrupt Southern Ocean eutrophication and the development of the Antarctic Circumpolar Current (ACC). Subsequently, evolutionary rates and disparity fell, becoming nearly constant after approximately 23 Ma as the ACC reached its full strength. By contrast, species diversity rose until 15 Ma and then remained stable, before dropping sharply with the onset of Northern Hemisphere glaciation. This decline coincided with the final establishment of modern mysticete gigantism and may be linked to glacially driven variability in the distribution of shallow habitats or an increased need for long-distance migration related to iron-mediated changes in glacial marine productivity. PMID:26064636

  6. When did Carcharocles megalodon become extinct? A new analysis of the fossil record.

    PubMed

    Pimiento, Catalina; Clements, Christopher F

    2014-01-01

    Carcharocles megalodon ("Megalodon") is the largest shark that ever lived. Based on its distribution, dental morphology, and associated fauna, it has been suggested that this species was a cosmopolitan apex predator that fed on marine mammals from the middle Miocene to the Pliocene (15.9-2.6 Ma). Prevailing theory suggests that the extinction of apex predators affects ecosystem dynamics. Accordingly, knowing the time of extinction of C. megalodon is a fundamental step towards understanding the effects of such an event in ancient communities. However, the time of extinction of this important species has never been quantitatively assessed. Here, we synthesize the most recent records of C. megalodon from the literature and scientific collections and infer the date of its extinction by making a novel use of the Optimal Linear Estimation (OLE) model. Our results suggest that C. megalodon went extinct around 2.6 Ma. Furthermore, when contrasting our results with known ecological and macroevolutionary trends in marine mammals, it became evident that the modern composition and function of modern gigantic filter-feeding whales was established after the extinction of C. megalodon. Consequently, the study of the time of extinction of C. megalodon provides the basis to improve our understanding of the responses of marine species to the removal of apex predators, presenting a deep-time perspective for the conservation of modern ecosystems. PMID:25338197

  7. Norwegian petroleum resources with focus on challenges and opportunities in the Barents Sea

    SciTech Connect

    Aamodt, F.R.

    1995-12-31

    The Norwegian Continental Shelf can be subdivided into 3 different petroleum provinces: (1) the North Sea, (2) the Norwegian Sea including the Jan Mayen ridge, and (3) the Barents Sea including the islands of Svalbard. The majority of the fields and discoveries and most of the resources are located in the mature North Sea Basin. Significant resources are however also discovered in the Norwegian Sea and the Barents Sea. 39 fields are in production or decided to be developed while 3 fields are closed down. Approximately 70% of the discovered resources are located in these fields, of which some are gigantic in size (Statfjord, Ekofisk, Gullfaks, Oseberg, Troll and Snorre). Most of the remaining discoveries (134) are smaller in size and approximately 2/3 of the resources are gas. According to a recent study carried out by the Norwegian Petroleum Directorate the expected undiscovered Norwegian Petroleum Resources are assessed to be on the order of 3,5 billion Sm{sup 3} o.e. with a level of uncertainty ranging from 2 to 6 billion Sm{sup 3} o.e. 40% of the undiscovered petroleum resources are expected to be found as oil. These are the perspectives of the Norwegian Petroleum Resources. The resources of the Barents Sea is included in this perspective. The significance of the Barents Sea resources is not particularly important in the short-medium term perspective, but will be important in the longer perspective.

  8. Mitochondrial fission is an acute and adaptive response in injured motor neurons.

    PubMed

    Kiryu-Seo, Sumiko; Tamada, Hiromi; Kato, Yukina; Yasuda, Katsura; Ishihara, Naotada; Nomura, Masatoshi; Mihara, Katsuyoshi; Kiyama, Hiroshi

    2016-01-01

    Successful recovery from neuronal damage requires a huge energy supply, which is provided by mitochondria. However, the physiological relevance of mitochondrial dynamics in damaged neurons in vivo is poorly understood. To address this issue, we established unique bacterial artificial chromosome transgenic (BAC Tg) mice, which develop and function normally, but in which neuronal injury induces labelling of mitochondria with green fluorescent protein (GFP) and expression of cre recombinase. GFP-labelled mitochondria in BAC Tg mice appear shorter in regenerating motor axons soon after nerve injury compared with mitochondria in non-injured axons, suggesting the importance of increased mitochondrial fission during the early phase of nerve regeneration. Crossing the BAC Tg mice with mice carrying a floxed dynamin-related protein 1 gene (Drp1), which is necessary for mitochondrial fission, ablates mitochondrial fission specifically in injured neurons. Injury-induced Drp1-deficient motor neurons show elongated or abnormally gigantic mitochondria, which have impaired membrane potential and axonal transport velocity during the early phase after injury, and eventually promote neuronal death. Our in vivo data suggest that acute and prominent mitochondrial fission during the early stage after nerve injury is an adaptive response and is involved in the maintenance of mitochondrial and neuronal integrity to prevent neurodegeneration. PMID:27319806

  9. Mutation update: the spectra of nebulin variants and associated myopathies.

    PubMed

    Lehtokari, Vilma-Lotta; Kiiski, Kirsi; Sandaradura, Sarah A; Laporte, Jocelyn; Repo, Pauliina; Frey, Jennifer A; Donner, Kati; Marttila, Minttu; Saunders, Carol; Barth, Peter G; den Dunnen, Johan T; Beggs, Alan H; Clarke, Nigel F; North, Kathryn N; Laing, Nigel G; Romero, Norma B; Winder, Thomas L; Pelin, Katarina; Wallgren-Pettersson, Carina

    2014-12-01

    A mutation update on the nebulin gene (NEB) is necessary because of recent developments in analysis methodology, the identification of increasing numbers and novel types of variants, and a widening in the spectrum of clinical and histological phenotypes associated with this gigantic, 183 exons containing gene. Recessive pathogenic variants in NEB are the major cause of nemaline myopathy (NM), one of the most common congenital myopathies. Moreover, pathogenic NEB variants have been identified in core-rod myopathy and in distal myopathies. In this update, we present the disease-causing variants in NEB in 159 families, 143 families with NM, and 16 families with NM-related myopathies. Eighty-eight families are presented here for the first time. We summarize 86 previously published and 126 unpublished variants identified in NEB. Furthermore, we have analyzed the NEB variants deposited in the Exome Variant Server (http://evs.gs.washington.edu/EVS/), identifying that pathogenic variants are a minor fraction of all coding variants (∼7%). This indicates that nebulin tolerates substantial changes in its amino acid sequence, providing an explanation as to why variants in such a large gene result in relatively rare disorders. Lastly, we discuss the difficulties of drawing reliable genotype-phenotype correlations in NEB-associated disease. PMID:25205138

  10. Modeling Variable Phanerozoic Oxygen Effects on Physiology and Evolution.

    PubMed

    Graham, Jeffrey B; Jew, Corey J; Wegner, Nicholas C

    2016-01-01

    Geochemical approximation of Earth's atmospheric O2 level over geologic time prompts hypotheses linking hyper- and hypoxic atmospheres to transformative events in the evolutionary history of the biosphere. Such correlations, however, remain problematic due to the relative imprecision of the timing and scope of oxygen change and the looseness of its overlay on the chronology of key biotic events such as radiations, evolutionary innovation, and extinctions. There are nevertheless general attributions of atmospheric oxygen concentration to key evolutionary changes among groups having a primary dependence upon oxygen diffusion for respiration. These include the occurrence of Devonian hypoxia and the accentuation of air-breathing dependence leading to the origin of vertebrate terrestriality, the occurrence of Carboniferous-Permian hyperoxia and the major radiation of early tetrapods and the origins of insect flight and gigantism, and the Mid-Late Permian oxygen decline accompanying the Permian extinction. However, because of variability between and error within different atmospheric models, there is little basis for postulating correlations outside the Late Paleozoic. Other problems arising in the correlation of paleo-oxygen with significant biological events include tendencies to ignore the role of blood pigment affinity modulation in maintaining homeostasis, the slow rates of O2 change that would have allowed for adaptation, and significant respiratory and circulatory modifications that can and do occur without changes in atmospheric oxygen. The purpose of this paper is thus to refocus thinking about basic questions central to the biological and physiological implications of O2 change over geological time. PMID:27343111

  11. Anomalously increased lifetimes of biological complexes at zero force due to the protein-water interface.

    PubMed

    Pereverzev, Yuriy V; Prezhdo, Oleg V; Sokurenko, Evgeni V

    2008-09-11

    A number of biological bonds show dramatically increased lifetimes at zero-force conditions, compared to lifetimes when even a small tensile force is applied to the ligand. The discrepancy is so great that it cannot be explained by the traditional receptor-ligand binding models. This generic phenomenon is rationalized here by considering the interaction of water with the receptor-ligand complex. It is argued that the water-protein interaction creates an energy barrier that prevents the ligand unbinding in the absence of the force. The properties of the interaction are such that even application of a relatively low force results in a dramatic drop of the bond lifetime due to the alteration of the water-receptor and water-ligand interaction network. The phenomenon is described by the presence of a second shallow interaction energy minimum for the bound ligand followed by a wide receptor-ligand dissociation barrier. The general analysis is applied quantitatively to the actin-myosin system, which demonstrates the gigantic drop of the bond lifetime at small forces and catch behavior (an increase in the lifetime) at moderate forces. The base hypothesis proposed to explain the small-force abnormal drop in the bond lifetime suggests that the majority of biological bonds may exhibit this phenomenon irrespectively whether they behave as slip or catch-slip bonds. PMID:18710275

  12. The acquisition of myelin: An evolutionary perspective.

    PubMed

    Zalc, B

    2016-06-15

    It has been postulated that the emergence of vertebrates was made possible by the acquisition of neural crest cells, which then led to the development of evolutionarily advantageous complex head structures (Gans and Northcutt, 1983). In this regard the contribution of one important neural crest derivative-the peripheral myelin sheath-to the success of the vertebrates has to be pointed out. Without this structure, the vertebrates, as we know them, simply could not exist. After briefly reviewing the major functions of the myelin sheath we will ask and provide tentative answers to the following three questions: when during evolution has myelin first appeared? Where has myelin initially appeared: in the CNS or in the PNS? Was it necessary to acquire a new cell type to form a myelin sheath? Careful examination of fossils lead us to conclude that myelin was acquired 425 MY ago by placoderms, the earliest hinge-jaw fishes. I argue that the acquisition of myelin during evolution has been a necessary prerequisite to permit gigantism of gnathostome species, including the sauropods. I propose that this acquisition occurred simultaneously in the PNS and CNS and that myelin forming cells are the descendants of ensheathing glia, already present in invertebrates, that have adapted their potential to synthesize large amount of membrane in response to axonal requirements. This article is part of a Special Issue entitled SI: Myelin Evolution. PMID:26367449

  13. Photochromism and polaronic photocharge localization in diluted KTa1-xNbxO3

    NASA Astrophysics Data System (ADS)

    Gubaev, A. I.; Kapphan, S. E.; Jastrabik, L.; Trepakov, V. A.; Syrnikov, P. P.

    2006-07-01

    Ultraviolet (UV)-light-induced optical absorption in the near infrared (NIR) region was observed in diluted KTa1-xNbxO3 single crystals (x =0,0.004,0.007,0.012,0.07) at low temperatures. Illumination by wideband light (3.10-4.13eV, 300-400nm) is accompanied by the appearance of a broad NIR absorption band with the position of the maxima varying in the 0.69-0.8eV (1.54-1.79μ, T =1.3K) region for different Nb concentrations. This UV-light-induced absorption is absent in nominally pure KTaO3, as well as in all Nb diluted specimens at elevated temperatures. The centers responsible for the photochromic NIR absorption bands are tied to interband optical transitions of pair Nb4+ electronic polarons. The photochromic experimental data, supplemented by luminescence studies in the visible range, evidence the strong localization of the photocharge carriers by pair Nb4+ polarons at low temperatures. It is suggested that namely the strong localization of the photocarriers plays a crucial role in photoinduced gigantic dielectric effects and possible phase transitions, which have been recognized recently in incipient ferroelectrics at low temperatures.

  14. Improved heat exhaust and the characteristics of the high Tc superconducting terahertz emitter

    NASA Astrophysics Data System (ADS)

    Kashiwagi, T.; Yamamoto, T.; Kitamura, T.; Asanuma, K.; Yasui, T.; Shibano, Y.; Watanabe, C.; Nakade, K.; Saiwai, Y.; Kubo, H.; Sakamoto, K.; Katsuragawa, T.; Tsujimoto, M.; Yoshizaki, R.; Minami, H.; Klemm, R. A.; Kadowaki, K.

    2015-03-01

    In our previous study it is known that THz emitting efficiency improves greatly when the stand-alone type of mesa structure is used for the THz emitting device. The principle reason for that lies in the heat removal from the mesa, in which a gigantic amount of heat is generated while the mesa is in the resistive state. Recently, we developed a new device structure based on the stand-alone type of mesa structure of Bi2212 single crystal in order to make high exhaust of Joule heating. The results show that although the power is comparable and is not significantly increased, very wide the radiation frequencies ranging from 0.3 to 1.6 THz were obtained. We will discuss the details of the radiation characteristics of this one. This study has been supported by CREST-JST. TK is also supported by the Matsuda grant and JST A-STEP. This work is in part performed in collaboration with Dr. Wai Kwok and his group in Argonne National Lab.

  15. Environmental and biotic controls on the evolutionary history of insect body size.

    PubMed

    Clapham, Matthew E; Karr, Jered A

    2012-07-01

    Giant insects, with wingspans as large as 70 cm, ruled the Carboniferous and Permian skies. Gigantism has been linked to hyperoxic conditions because oxygen concentration is a key physiological control on body size, particularly in groups like flying insects that have high metabolic oxygen demands. Here we show, using a dataset of more than 10,500 fossil insect wing lengths, that size tracked atmospheric oxygen concentrations only for the first 150 Myr of insect evolution. The data are best explained by a model relating maximum size to atmospheric environmental oxygen concentration (pO(2)) until the end of the Jurassic, and then at constant sizes, independent of oxygen fluctuations, during the Cretaceous and, at a smaller size, the Cenozoic. Maximum insect size decreased even as atmospheric pO(2) rose in the Early Cretaceous following the evolution and radiation of early birds, particularly as birds acquired adaptations that allowed more agile flight. A further decrease in maximum size during the Cenozoic may relate to the evolution of bats, the Cretaceous mass extinction, or further specialization of flying birds. The decoupling of insect size and atmospheric pO(2) coincident with the radiation of birds suggests that biotic interactions, such as predation and competition, superseded oxygen as the most important constraint on maximum body size of the largest insects. PMID:22665762

  16. "So it really does exist-the sea-Serpent we've never believed in!" Ferenczi's influence on Freud revisited.

    PubMed

    Bonomi, Carlo

    2013-12-01

    In the last phase of his work, Ferenczi created a new language for trauma, based on the fragmentation of mental life. In the paper on "The principles of relaxation and neocatharsis," Ferenczi reformulated the goal of analysis by proposing that "no analysis can be regarded … as complete unless we have succeed in penetrating the traumatic material", where the "traumatic material" was not to be sought in the neurotic reactions and adaptive solutions of the ego but in more primitive reactions, such as the psychotic turning away from reality, splitting, and fragmentation. This was exactly the material that Freud assimilated in the essay "A disturbance of memory on the Acropolis", after the death of Ferenczi. Freud visited Athens in 1904, and the walk up to the Parthenon represented the successful coronation of his self-analysis. Actually, the hallucination turned out to be so uncanny that he never again visited Athens. In a letter to Fliess, written shortly before the meeting in Nuremberg, on January 24, 1897, Freud reported on a case history turning on a "scene about the circumcision of a girl," who later was convincingly identified by Schur as Emma Eckstein. Did Freud have the germinal idea that Emma Eckstein's hallucination of the penis contained the wish to overcome her trauma and the hope to have a restored genital? Is this the holy visitation, which haunted him on the Acropolis? Why did he give up the profound insight that the dreams of gigantic snakes had a traumatic origin? PMID:24309686

  17. A case of bilateral macrodontia of mandibular second premolars from a Chalcolithic context in the Iberian Peninsula.

    PubMed

    López-Onaindia, Diego; Otxoa de Amezaga, Amaia; Subirà, M Eulàlia

    2015-01-01

    Isolated macrodontia, consisting of the gigantism of a single tooth, is an extremely rare condition. Only 16 cases of isolated macrodontia of mandibular second premolars have been reported to date. Although the aetiology of this phenomenon remains unknown, many authors have related it to the control of the apoptotic process, leading to the patterning and size of dental cusps. There is not a clear genetic inheritance pattern since only two of those 16 cases correspond to close relatives. To our knowledge, there have been no reports of isolated macrodontia of mandibular second premolars in archaeological remains. Cova del Pantà de Foix site is a Chalcolithic sepulchral cave situated in the North-East of the Iberian Peninsula in which the remains of at least 30 individuals were recovered. Most of these individuals show several signs of environmental stressors. The current study presents the first case of isolated bilateral macrodontia of mandibular premolars from an archaeological context, corresponding to a young male individual discovered in this site. This condition could be the last consequence of environmental factors epigenetically affecting apoptosis processes in early tooth development and a possible genetic predisposition to show a shape-deviation in the dentition. PMID:26133014

  18. Developmental palaeontology in synapsids: the fossil record of ontogeny in mammals and their closest relatives

    PubMed Central

    Sánchez-Villagra, Marcelo R.

    2010-01-01

    The study of fossilized ontogenies in mammals is mostly restricted to postnatal and late stages of growth, but nevertheless can deliver great insights into life history and evolutionary mechanisms affecting all aspects of development. Fossils provide evidence of developmental plasticity determined by ecological factors, as when allometric relations are modified in species which invaded a new space with a very different selection regime. This is the case of dwarfing and gigantism evolution in islands. Skeletochronological studies are restricted to the examination of growth marks mostly in the cement and dentine of teeth and can provide absolute age estimates. These, together with dental replacement data considered in a phylogenetic context, provide life-history information such as maturation time and longevity. Palaeohistology and dental replacement data document the more or less gradual but also convergent evolution of mammalian growth features during early synapsid evolution. Adult phenotypes of extinct mammals can inform developmental processes by showing a combination of features or levels of integration unrecorded in living species. Some adult features such as vertebral number, easily recorded in fossils, provide indirect information about somitogenesis and hox-gene expression boundaries. Developmental palaeontology is relevant for the discourse of ecological developmental biology, an area of research where features of growth and variation are fundamental and accessible among fossil mammals. PMID:20071389

  19. Choosing Between Yeast and Bacterial Expression Systems: Yield Dependent

    NASA Technical Reports Server (NTRS)

    Miller, Rebecca S.; Malone, Christine C.; Moore, Blake P.; Burk, Melissa; Crawford, Lisa; Karr, Laurel J.; Curreri, Peter A. (Technical Monitor)

    2002-01-01

    Green fluorescent protein (GFP) is a naturally occurring fluorescent protein isolated from the jellyfish Aequorea victoria. The intrinsic fluorescence of the protein is due to a chromophore located in the center of the molecule. Its usefulness has been established as a marker for gene expression and localization of gene products. GFP has recently been utilized as a model protein for crystallization studies at NASA/MSFC, both in earth-based and in microgravity experiments. Because large quantities of purified protein were needed, the cDNA of GFP was cloned into the Pichia pastoris pPICZ(alpha) C strain, with very little protein secreted into the media. Microscopic analysis prior to harvest showed gigantic green fluorescent yeast, but upon harvesting most protein was degraded. Trial fermentations of GFP cloned into pPICZ A for intracellular expression provided unsatisfactory yield. GFP cloned into E, coli was overexpressed at greater than 150 mg/liter, with purification yields at greater than 100mg/liter.

  20. Mythology and Neurosurgery.

    PubMed

    Ökten, Ali İhsan

    2016-06-01

    Myths are the keystone of mythology. They are interpretations of events that have been told as stories and legends for thousands of years, inherited from generation to generation, and have reached the present day. Although most myths are considered figments of the imagination or fictitious legends, all of them contain references to facts from the time they occurred. Mythology, which is a collection of figments of imagination concerning nature and human beings, is a product of human effort to perceive, explain, and interpret the universe and the world, much like science. The interaction between mythology and science dates back to the early days of civilization. Mythology, a reflection of human creativity, is extensively used in modern science, particularly in a terminological context. This article aims to reveal the texture of mythology in neurosurgery, by analyzing the birth of medicine in mythology; heroes such as Apollo and Asklepios, the gods of healing and medicine, as well as Hygieia, the goddess of health and hygiene; and mythological terms and phrases such as Achilles tendon, atlas vertebra, gigantism, priapism syndrome, hippocampus, lethargy, syrinx, and arachnoid. Through the use of symbols, mythology has attempted to explain several subjects, such as human nature, disease, birth, and death. In this respect, mythology and medicine dance arm in arm, and this dance has been going on for centuries. As a result, mythology has manifested itself in many fields within medicine, either anatomically or by giving names to various diseases. PMID:26970479

  1. Catastrophic flood origin, little Missouri River valley, Montana, South Dakota, and North Dakota

    SciTech Connect

    Clausen, E.N.

    1988-07-01

    Mosaics of photographically reduced topographic maps demonstrate the Little Missouri River valley was developed by gigantic floods. Catastrophic flood landforms, oriented in a northwest-southeast direction, cross the entire Little Missouri drainage basin. Field evidence, consisting of abundant flood-deposited alluvium, supports map evidence. Flood-produced landforms, cut in easily eroded claystone bedrock, appear fresh, suggesting that floods occurred late during the last glacial cycle. Sheets of water, several hundred kilometers wide, flowed in a southeast direction, parallel with a continental ice margin. Erosion lowered the regional surface from a level corresponding to the tops of the highest present-day buttes to the surface now crossed by the headwaters of the Moreau, Grand, Cannonball, Heart, and Green Rivers. Spillway trenches served to channel flow and rapidly cut headward into easily eroded claystone. These trenches include the Moreau, Grand, Cannonball, Heart, and Missouri valleys. The Missouri valley in western North Dakota became the dominant spillway as tributary trenches systematically cut off flow feeding competing spillways. Formation of the Little Missouri spillway, first as a north-trending valley, progressively cut off floodwaters flowing into the Heart, Cannonball, Grand, and Moreau spillways. The north end of the Little Missouri spillway also was cut off by a deeper east-trending spillway. Huge sheets of floodwater continued to pour across the divide west of the Little Missouri continuing to lower that surface. These floodwaters were cut off by development of the Yellowstone spillway in eastern Montana.

  2. Highly viscous liquid crystalline mixtures: the alternative to liquid crystalline elastomers

    NASA Astrophysics Data System (ADS)

    Shibaev, Petr; Schlesier, Cristina; Newman, Leah; McDonald, Scott

    2012-02-01

    Novel highly viscous liquid crystalline materials based on mixtures of glass forming oligomers and low molar mass liquid crystals were recently designed [1, 2] and studied. In this communication the novel data are presented, the analysis and discussion are extended. It is shown that viscoelastic properties of the materials are due to the physical entanglements between cyclic oligomers and low molar mass mesogens, not due to the chemical crosslinks between molecular moities. However, the mechanical properties of these viscoelastic materials resemble those of chemically crosslinked elastomers (elasticity and reversibility of deformations). The properties of chiral and non-chiral materials loaded with ferromagnetic nanoparticles are discussed in detail. Cholesteric materials undergo gigantic color changes in the wide spectral range under the deformation that allows distant detection of deformation and determination the anisotropy of deformation and its type. The materials doped with laser dyes become mechanically tunable lasers themselves and emit coherent light while pumped by external laser. A simple model is suggested to account for the observed effects; physical properties of the novel materials and liquid crystalline elastomers are compared and discussed. [4pt] [1] P.V. Shibaev, C. Schlesier, R. Uhrlass, S. Woodward, E. Hanelt, Liquid Crystals, 37:12, 1601-1604 [0pt] [2] P.V. Shibaev, P. Riverra, D. Teter, S. Marsico, M. Sanzari, V. Ramakrishnan, E. Hanelt, Optics Express, 16, 2965 (2008)

  3. Protein Dynamics

    NASA Astrophysics Data System (ADS)

    Frauenfelder, Hans

    2011-03-01

    Proteins combine properties of solids, liquids, and glasses. Schrödinger anticipated the main features of biomolecules long ago by stating that they had to be solid-like, but able to assume many different conformations. Indeed proteins can assume a gigantic number of conformational substates with the same primary sequence but different conformations. The different substates are described as craters in a very-high-dimensional energy landscape. The energy landscape is organized in a hierarchy of tiers, craters within craters within craters. Protein motions are pictured as transition between substates - jumps from crater to crater. Initially we assumed that these jumps were controlled by internal barriers between substates, but experiments have shown that nature selected a different approach. Proteins are surrounded by one to two layers of water and are embedded in a bulk solvent. Structural motions of the protein are controlled by the alpha fluctuations in the solvent surrounding the protein. Some internal motions most likely involving side chains are controlled electrostatically by beta fluctuations in the hydration shell. The dynamics of proteins is consequently dominated by the environment (H. Frauenfelder et al. PNAS 106, 5129 (2009). One can speculate that this organization permits exchange of information among biomolecules. The energy landscape is not just organized into two tiers, alpha and beta, but cryogenic experiments have revealed more tiers and protein more properties similar to that of glasses. While proteins function at ambient temperatures, cryogenic studies are necessary to understand the physics relevant for biology.

  4. Earth After the Moon Forming Impact

    NASA Technical Reports Server (NTRS)

    Zahnle, Kevin

    2006-01-01

    The Hadean Earth is widely and enduringly pictured as a world of exuberant volcanism, exploding meteors, huge craters, infernal heat, and billowing sulfurous steams; i.e., a world of fire and brimstone punctuated with blows to the head. In the background the Moon looms gigantic in the sky. The popular image has given it a name that celebrates our mythic roots. A hot early Earth is an inevitable consequence of accretion. The Moon-forming impact ensured that Earth as we know it emerged from a fog of silicate vapor. The impact separated the volatiles from the silicates. It took -100 years to condense and rain out the bulk of the vaporized silicates, although relatively volatile elements may have remained present in the atmosphere throughout the magma ocena stage. The magma ocean lasted approx. 2 Myr, its lifetime prolonged by tidal heating and thermal blanketing by a thick (CO2-rich steam atmosphere. Water oceans condensed quickly after the mantle solidified, but for some 10-100 Myr the surface would have stayed warm (approx. 500 K) until the CO2 was removed into the mantle. Thereafter the faint young Sun suggests that a lifeless Earth would always have been evolving toward a bitterly cold ice world, but the cooling trend was frequently interrupted by volcanic or impact induced thaws.

  5. VLF Science at Indian Centre for Space Physics

    NASA Astrophysics Data System (ADS)

    Chakrabarti, Sandip Kumar

    2016-07-01

    Indian Centre for Space Physics has been monitoring VLF signals from stations around the world at its laboratories at Kolkata and Sitapur (Ionospheric and Earthquake Research Centre) as well as at several places throughout India when in a campaign mode. We have been interested to study high energy events from space, such as solar flares and gamma ray bursts. We have made studies during multiple solar eclipses and most importantly made substantial progress in the problem of lithosphere-ionosphere coupling while understanding various types of anomalies prior to major earthquakes. Other effects such as AGWs and LEPs are being studied. We have experience of two antarctic expedition and obtained VLF data from both Maitri and Bharati stations of India, which revealed, among other things, how the signal attenuation can indicate the extent of ice mass in Antarctica. We have been able to reproduce various VLF perturbation events using Atmospheric Chemical evolution model coupled with LWPC code. For instance we have reproduced solar flare induced VLF amplitude perturbation pattern by completely ab initio calculation. We also targeted the inverse problem, namely, deduction of the injected radiation spectra from space from the VLF signal alone, thereby establishing that the Earth can be used as a gigantic detector. These interesting results would be presented in my review talk.

  6. What big eyes you have: the ecological role of giant pterygotid eurypterids.

    PubMed

    Anderson, Ross P; McCoy, Victoria E; McNamara, Maria E; Briggs, Derek E G

    2014-07-01

    Eurypterids are a group of extinct chelicerates that ranged for over 200 Myr from the Ordovician to the Permian. Gigantism is common in the group; about 50% of families include taxa over 0.8 m in length. Among these were the pterygotids (Pterygotidae), which reached lengths of over 2 m and were the largest arthropods that ever lived. They have been interpreted as highly mobile visual predators on the basis of their large size, enlarged, robust chelicerae and forward-facing compound eyes. Here, we test this interpretation by reconstructing the visual capability of Acutiramus cummingsi (Pterygotidae) and comparing it with that of the smaller Eurypterus sp. (Eurypteridae), which lacked enlarged chelicerae, and other arthropods of similar geologic age. In A. cummingsi, there is no area of lenses differentiated to provide increased visual acuity, and the interommatidial angles (IOA) do not fall within the range of high-level modern arthropod predators. Our results show that the visual acuity of A. cummingsi is poor compared with that of co-occurring Eurypterus sp. The ecological role of pterygotids may have been as predators on thin-shelled and soft-bodied prey, perhaps in low-light conditions or at night. PMID:25009243

  7. New tyrannosaur from the mid-Cretaceous of Uzbekistan clarifies evolution of giant body sizes and advanced senses in tyrant dinosaurs

    NASA Astrophysics Data System (ADS)

    Brusatte, Stephen L.; Averianov, Alexander; Sues, Hans-Dieter; Muir, Amy; Butler, Ian B.

    2016-03-01

    Tyrannosaurids-the familiar group of carnivorous dinosaurs including Tyrannosaurus and Albertosaurus-were the apex predators in continental ecosystems in Asia and North America during the latest Cretaceous (ca. 80-66 million years ago). Their colossal sizes and keen senses are considered key to their evolutionary and ecological success, but little is known about how these features developed as tyrannosaurids evolved from smaller basal tyrannosauroids that first appeared in the fossil record in the Middle Jurassic (ca. 170 million years ago). This is largely because of a frustrating 20+ million-year gap in the mid-Cretaceous fossil record, when tyrannosauroids transitioned from small-bodied hunters to gigantic apex predators but from which no diagnostic specimens are known. We describe the first distinct tyrannosauroid species from this gap, based on a highly derived braincase and a variety of other skeletal elements from the Turonian (ca. 90-92 million years ago) of Uzbekistan. This taxon is phylogenetically intermediate between the oldest basal tyrannosauroids and the latest Cretaceous forms. It had yet to develop the giant size and extensive cranial pneumaticity of T. rex and kin but does possess the highly derived brain and inner ear characteristic of the latest Cretaceous species. Tyrannosauroids apparently developed huge size rapidly during the latest Cretaceous, and their success in the top predator role may have been enabled by their brain and keen senses that first evolved at smaller body size.

  8. New tyrannosaur from the mid-Cretaceous of Uzbekistan clarifies evolution of giant body sizes and advanced senses in tyrant dinosaurs.

    PubMed

    Brusatte, Stephen L; Averianov, Alexander; Sues, Hans-Dieter; Muir, Amy; Butler, Ian B

    2016-03-29

    Tyrannosaurids--the familiar group of carnivorous dinosaurs including Tyrannosaurus and Albertosaurus--were the apex predators in continental ecosystems in Asia and North America during the latest Cretaceous (ca. 80-66 million years ago). Their colossal sizes and keen senses are considered key to their evolutionary and ecological success, but little is known about how these features developed as tyrannosaurids evolved from smaller basal tyrannosauroids that first appeared in the fossil record in the Middle Jurassic (ca. 170 million years ago). This is largely because of a frustrating 20+ million-year gap in the mid-Cretaceous fossil record, when tyrannosauroids transitioned from small-bodied hunters to gigantic apex predators but from which no diagnostic specimens are known. We describe the first distinct tyrannosauroid species from this gap, based on a highly derived braincase and a variety of other skeletal elements from the Turonian (ca. 90-92 million years ago) of Uzbekistan. This taxon is phylogenetically intermediate between the oldest basal tyrannosauroids and the latest Cretaceous forms. It had yet to develop the giant size and extensive cranial pneumaticity of T. rex and kin but does possess the highly derived brain and inner ear characteristic of the latest Cretaceous species. Tyrannosauroids apparently developed huge size rapidly during the latest Cretaceous, and their success in the top predator role may have been enabled by their brain and keen senses that first evolved at smaller body size. PMID:26976562

  9. Linquistic geometry: new technology for decision support

    NASA Astrophysics Data System (ADS)

    Stilman, Boris; Yakhnis, Vladimir

    2003-09-01

    Linguistic Geometry (LG) is a revolutionary gaming approach which is ideally suited for military decision aids for Air, Ground, Naval, and Space-based operations, as well guiding robotic vehicles and traditional entertainment games. When thinking about modern or future military operations, the game metaphor comes to mind right away. Indeed, the air space together with the ground and seas may be viewed as a gigantic three-dimensional game board. Refining this picture, the LG approach is capable of providing an LG hypergame, that is, a system of multiple concurrent interconnected multi-player abstract board games (ABG) of various resolutions and time frames reflecting various kinds of hardware and effects involved in the battlespace and the solution space. By providing a hypergame representation of the battlespace, LG already provides a significant advance in situational awareness. However, the greatest advantage of the LG approach is an ability to provide commanders of campaigns and missions with decision options resulting in attainment of the commander's intent. At each game turn, an LG decision support tool assigns the best actions to each of the multitude of battlespace actors (UAVs, bombers, cruise missiles, etc.). This is done through utilization of algorithms finding winning strategies and tactics, which are the core of the LG approach.

  10. The evolutionary physiology of animal flight: paleobiological and present perspectives.

    PubMed

    Dudley, R

    2000-01-01

    Recent geophysical analyses suggest the presence of a late Paleozoic oxygen pulse beginning in the late Devonian and continuing through to the late Carboniferous. During this period, plant terrestrialization and global carbon deposition resulted in a dramatic increase in atmospheric oxygen levels, ultimately yielding concentrations potentially as high as 35% relative to the contemporary value of 21%. Such hyperoxia of the late Paleozoic atmosphere may have physiologically facilitated the initial evolution of insect flight metabolism. Widespread gigantism in late Paleozoic insects and other arthropods is also consistent with enhanced oxygen flux within diffusion-limited tracheal systems. Because total atmospheric pressure increases with increased oxygen partial pressure, concurrently hyperdense conditions would have augmented aerodynamic force production in early forms of flying insects. By the late Permian, evolution of decompositional microbial and fungal communities, together with disequilibrium in rates of carbon deposition, gradually reduced oxygen concentrations to values possibly as low as 15%. The disappearance of giant insects by the end of the Permian is consistent with extinction of these taxa for reasons of asphyxiation on a geological time scale. As with winged insects, the multiple historical origins of vertebrate flight in the late Jurassic and Cretaceous correlate temporally with periods of elevated atmospheric oxygen. Much discussion of flight performance in Archaeopteryx assumes a contemporary atmospheric composition. Elevated oxygen levels in the mid- to late Mesozoic would, however, have facilitated aerodynamic force production and enhanced muscle power output for ancestral birds, as well as for precursors to bats and pterosaurs. PMID:10845087

  11. Planet Mars: Story of Another World

    NASA Astrophysics Data System (ADS)

    Leatherland, Alex

    2009-05-01

    Mars has captured the imagination of people throughout the ages, inspiring many stories. Remarkably, though, little was known about the red planet until recently. Through a great deal of exploration and theory, planetary scientists have striven to correct this situation. Over the course of the past half century, since the first flyby of Mars by NASA's Mariner 4 spacecraft in 1967, a multitude of probes have landed on, orbited, and flown past the planet. From these missions, a great deal has been learned about Mars. Its surface has now been studied to a respectable level of detail, revealing an astonishing amount of information about volcanoes such as Olympus Mons in Mars's Tharsis region; about the gigantic Valles Marineris (Valley of Wonder), the largest known canyon in the solar system; and about lava flows, outflow channels, and the Martian regolith, among many other aspects of the planet. This level of detail is made more incredible because of the difficulty in gathering such information. And there is still a staggering wealth of learning left to do. This book provides an overview of the current understanding of the past and present state of Mars, and a brief introduction to the planet.

  12. Creating the brain and interacting with the brain: an integrated approach to understanding the brain.

    PubMed

    Morimoto, Jun; Kawato, Mitsuo

    2015-03-01

    In the past two decades, brain science and robotics have made gigantic advances in their own fields, and their interactions have generated several interdisciplinary research fields. First, in the 'understanding the brain by creating the brain' approach, computational neuroscience models have been applied to many robotics problems. Second, such brain-motivated fields as cognitive robotics and developmental robotics have emerged as interdisciplinary areas among robotics, neuroscience and cognitive science with special emphasis on humanoid robots. Third, in brain-machine interface research, a brain and a robot are mutually connected within a closed loop. In this paper, we review the theoretical backgrounds of these three interdisciplinary fields and their recent progress. Then, we introduce recent efforts to reintegrate these research fields into a coherent perspective and propose a new direction that integrates brain science and robotics where the decoding of information from the brain, robot control based on the decoded information and multimodal feedback to the brain from the robot are carried out in real time and in a closed loop. PMID:25589568

  13. Genome project: An experiment in sharing

    SciTech Connect

    Roberts, L.

    1990-05-25

    The Human Genome Project is in many respects a gigantic experiment in data sharing. Around the world, investigators are working on pieces of the same puzzle. And whether the project succeeds will depend in large measure on these investigators making available their data and materials - cell lines, probes, and clones - to their colleagues and competitors. While sharing may be the norm in, say, immunology or bacterial genetics, human genetics has always been intensely competitive. So should the National Institutes of Health and the Department of Energy, which both fund the genome project, promulgate rules to govern access to data and sharing of materials A DOE committee has drafted some guidelines, which have yet to be formally endorsed. They stipulate that data and materials must be publicly available 6 months after they are generated or characterized. But at NIH, James Watson, who heads the genome project, is shying away from setting rules. He points to the new collaborative plans to map chromosome 21 as evidence that the community will develop its own ways of sharing data. Because of its known role in Down syndrome and its suspected role in Alzheimer's disease, chromosome 21 has generated a vast amount of interest. Lots of groups are already hard at work constructing maps of the chromosome - first developing a series of landmarks spaced along the chromosome, and then a collection of ordered DNA fragments. But the maps all these groups generate will be essentially useless unless they pool their data and adopt a common language.

  14. The Influence of Extremely Large Solar Proton Events in a Changing Stratosphere. Stratospheric Influence of Solar Proton Events

    NASA Technical Reports Server (NTRS)

    Jackman, Charles H.; Fleming, Eric L.; Vitt, Francis M.

    1999-01-01

    Two periods of extremely large solar proton events (SPEs) occurred in the past thirty years, which forced significant long-term polar stratospheric changes. The August 2-10, 1972 and October 19-27, 1989 SPEs happened in stratospheres that were quite different chemically. The stratospheric chlorine levels were relatively small in 1972 (approximately 1.2 ppbv) and were fairly substantial in 1989 at about (approximately 3 ppbv). Although these SPEs produced both HO(x) and NO(y) constituents in the mesosphere and stratosphere, only the NO(y) constituents had lifetimes long enough to affect ozone for several months to years past the events. Our recently improved two-dimensional chemistry and transport atmospheric model was used to compute the effects of these gigantic SPEs in a changing stratosphere. Significant upper stratospheric ozone depletions > 10% are computed to last for a few months past these SPEs. The long-lived SPE-produced NO(y) constituents were transported to lower levels during winter after these huge SPEs and caused impacts in the middle and lower stratosphere. During periods of high halogen loading these impacts resulted in interference with the chlorine and bromine loss cycles for ozone destruction. The chemical state of the atmosphere, including the stratospheric sulfate aerosol density, substantially affected the predicted stratospheric influence of these extremely large SPEs.

  15. [Clinical picture and pathomorphology of acute coenuriasis in sheep].

    PubMed

    Angelov, A K; Belchev, L

    1986-01-01

    Clinical and morphological investigations were carried out in the case of two enzootics of coenurosis in weaned lambs. The disease was established in two flocks of 180 and 160 animals, respectively. Outbreaks were recorded two weeks after they were put on premises where dogs untreated for worms had been kept. Instable gait and incoordinated movements of the head and limbs were observed along with circling movements of the body, loss of herd instinct, and lay ill for a long time. Morphologically, hyperemia was seen in the meninges, hemispheres, cerebellum, and the basal portions of the brain, with swelling of the tissue, numerous oncospheres, and purulent and necrotic foci. Histopathologically, there were in the acute stages great numbers of parasite passages with detritus mass, hemorrhages, purulent-and-necrotic meningoencephalitis, and higher counts of neutrophile and eosinophile granulocytes. Besides, in the subacute cases there were histiocytes and lymphoid and gigantic alien cells. Differential diagnosis should take into consideration listeriosis, cerebrocortical necrosis, estrosis monesiosis, and enterotoxemia. PMID:3765379

  16. An improved distance matrix computation algorithm for multicore clusters.

    PubMed

    Al-Neama, Mohammed W; Reda, Naglaa M; Ghaleb, Fayed F M

    2014-01-01

    Distance matrix has diverse usage in different research areas. Its computation is typically an essential task in most bioinformatics applications, especially in multiple sequence alignment. The gigantic explosion of biological sequence databases leads to an urgent need for accelerating these computations. DistVect algorithm was introduced in the paper of Al-Neama et al. (in press) to present a recent approach for vectorizing distance matrix computing. It showed an efficient performance in both sequential and parallel computing. However, the multicore cluster systems, which are available now, with their scalability and performance/cost ratio, meet the need for more powerful and efficient performance. This paper proposes DistVect1 as highly efficient parallel vectorized algorithm with high performance for computing distance matrix, addressed to multicore clusters. It reformulates DistVect1 vectorized algorithm in terms of clusters primitives. It deduces an efficient approach of partitioning and scheduling computations, convenient to this type of architecture. Implementations employ potential of both MPI and OpenMP libraries. Experimental results show that the proposed method performs improvement of around 3-fold speedup upon SSE2. Further it also achieves speedups more than 9 orders of magnitude compared to the publicly available parallel implementation utilized in ClustalW-MPI. PMID:25013779

  17. Intercontinental dispersal of giant thermophilic ants across the Arctic during early Eocene hyperthermals

    PubMed Central

    Archibald, S. Bruce; Johnson, Kirk R.; Mathewes, Rolf W.; Greenwood, David R.

    2011-01-01

    Early Eocene land bridges allowed numerous plant and animal species to cross between Europe and North America via the Arctic. While many species suited to prevailing cool Arctic climates would have been able to cross throughout much of this period, others would have found dispersal opportunities only during limited intervals when their requirements for higher temperatures were met. Here, we present Titanomyrma lubei gen. et sp. nov. from Wyoming, USA, a new giant (greater than 5 cm long) formiciine ant from the early Eocene (approx. 49.5 Ma) Green River Formation. We show that the extinct ant subfamily Formiciinae is only known from localities with an estimated mean annual temperature of about 20°C or greater, consistent with the tropical ranges of almost all of the largest living ant species. This is, to our knowledge, the first known formiciine of gigantic size in the Western Hemisphere and the first reported cross-Arctic dispersal by a thermophilic insect group. This implies intercontinental migration during one or more brief high-temperature episodes (hyperthermals) sometime between the latest Palaeocene establishment of intercontinental land connections and the presence of giant formiciines in Europe and North America by the early middle Eocene. PMID:21543354

  18. McCune Albright syndrome in association with excessive GH secretion: case report

    PubMed Central

    Özsu, Elif; Mutlu, Gül Yeşiltepe; Çizmecioğlu, Filiz Mine; Hatun, Şükrü

    2015-01-01

    McCune-Albright Syndrome is a rare syndrome characterized with excessive function of peripheral endocrine organs and activating mutations of the stimulatory G protein alpha subunit are involved in the pathogenesis. The three main findings of the disease include hyperpigmented café au lait spots, fibrous dysplasia and increased endocrine functions and excessive secretion of growth hormone is observed in 21% of the patients. Clinical signs may be missed in these patients because of precocious puberty and craniofacial fibrous dysplasia. Since radiotherapy causes to sarcomatous changes and transsphenoidal surgery may cause to severe thickening in the cranial bones, they are not appropriate treatment options and medical treatment is recommended. Bromocriptine, cabergoline and octreotide or different combinations of these drugs are used in treatment and pegvisomant has also been used in recent years. Here, we present a male patient aged 12 years and 7 months to show gigantism as a rare clinical reflection of McCune-Albright Syndrome with an excessive height (197 cm), café au lait spots, growht hormone levels which could not be supressed with oral glucose tolerance test and increased prolactin levels. PMID:26265896

  19. Pituitary Tumors in Childhood: an update in their diagnosis, treatment and molecular genetics

    PubMed Central

    Keil, Margaret F.; Stratakis, Constantine A.

    2009-01-01

    Pituitary tumors are rare in childhood and adolescence, with a reported prevalence of up to 1 per million children. Only 2 - 6% of surgically treated pituitary tumors occur in children. Although pituitary tumors in children are almost never malignant and hormonal secretion is rare, these tumors may result in significant morbidity. Tumors within the pituitary fossa are of two types mainly, craniopharyngiomas and adenomas; craniopharyngiomas cause symptoms by compressing normal pituitary, causing hormonal deficiencies and producing mass effects on surrounding tissues and the brain; adenomas produce a variety of hormonal conditions such as hyperprolactinemia, Cushing disease and acromegaly or gigantism. Little is known about the genetic causes of sporadic lesions, which comprise the majority of pituitary tumors, but in children, more frequently than in adults, pituitary tumors may be a manifestation of genetic conditions such as multiple endocrine neoplasia type 1 (MEN 1), Carney complex, familial isolated pituitary adenoma (FIPA), and McCune-Albright syndrome. The study of pituitary tumorigenesis in the context of these genetic syndromes has advanced our knowledge of the molecular basis of pituitary tumors and may lead to new therapeutic developments. PMID:18416659

  20. Atmospheric oxygen level and the evolution of insect body size

    PubMed Central

    Harrison, Jon F.; Kaiser, Alexander; VandenBrooks, John M.

    2010-01-01

    Insects are small relative to vertebrates, possibly owing to limitations or costs associated with their blind-ended tracheal respiratory system. The giant insects of the late Palaeozoic occurred when atmospheric PO2 (aPO2) was hyperoxic, supporting a role for oxygen in the evolution of insect body size. The paucity of the insect fossil record and the complex interactions between atmospheric oxygen level, organisms and their communities makes it impossible to definitively accept or reject the historical oxygen-size link, and multiple alternative hypotheses exist. However, a variety of recent empirical findings support a link between oxygen and insect size, including: (i) most insects develop smaller body sizes in hypoxia, and some develop and evolve larger sizes in hyperoxia; (ii) insects developmentally and evolutionarily reduce their proportional investment in the tracheal system when living in higher aPO2, suggesting that there are significant costs associated with tracheal system structure and function; and (iii) larger insects invest more of their body in the tracheal system, potentially leading to greater effects of aPO2 on larger insects. Together, these provide a wealth of plausible mechanisms by which tracheal oxygen delivery may be centrally involved in setting the relatively small size of insects and for hyperoxia-enabled Palaeozoic gigantism. PMID:20219733

  1. Wafer-scale metasurface for total power absorption, local field enhancement and single molecule Raman spectroscopy

    PubMed Central

    Wang, Dongxing; Zhu, Wenqi; Best, Michael D.; Camden, Jon P.; Crozier, Kenneth B.

    2013-01-01

    The ability to detect molecules at low concentrations is highly desired for applications that range from basic science to healthcare. Considerable interest also exists for ultrathin materials with high optical absorption, e.g. for microbolometers and thermal emitters. Metal nanostructures present opportunities to achieve both purposes. Metal nanoparticles can generate gigantic field enhancements, sufficient for the Raman spectroscopy of single molecules. Thin layers containing metal nanostructures (“metasurfaces”) can achieve near-total power absorption at visible and near-infrared wavelengths. Thus far, however, both aims (i.e. single molecule Raman and total power absorption) have only been achieved using metal nanostructures produced by techniques (high resolution lithography or colloidal synthesis) that are complex and/or difficult to implement over large areas. Here, we demonstrate a metasurface that achieves the near-perfect absorption of visible-wavelength light and enables the Raman spectroscopy of single molecules. Our metasurface is fabricated using thin film depositions, and is of unprecedented (wafer-scale) extent. PMID:24091825

  2. Measuring engagement effectiveness in social media

    NASA Astrophysics Data System (ADS)

    Li, Lei; Sun, Tong; Peng, Wei; Li, Tao

    2012-03-01

    Social media is becoming increasingly prevalent with the advent of web 2.0 technologies. Popular social media websites, such as Twitter and Facebook, are attracting a gigantic number of online users to post and share information. An interesting phenomenon under this trend involves that more and more users share their experiences or issues with regard to a product, and then the product service agents use commercial social media listening and engagement tools (e.g. Radian6, Sysomos, etc.) to response to users' complaints or issues and help them tackle their problems. This is often called customer care in social media or social customer relationship management (CRM). However, all these existing commercial social media tools only provide an aggregated level of trends, patterns and sentiment analysis based on the keyword-centric brand relevant data, which have little insights for answering one of the key questions in social CRM system: how effective is our social customer care engagement? In this paper, we focus on addressing the problem of how to measure the effectiveness of engagement for service agents in customer care. Traditional CRM effectiveness measurements are defined under the scenario of the call center, where the effectiveness is mostly based on the duration time per call and/or number of answered calls per day. Different from customer care in a call center, we can obtain detailed conversations between agents and customers in social media, and therefore the effectiveness can be measured by analyzing the content of conversations and the sentiment of customers.

  3. Complex Commingling: Nucleoporins and the Spindle Assembly Checkpoint

    PubMed Central

    Mossaid, Ikram; Fahrenkrog, Birthe

    2015-01-01

    The segregation of the chromosomes during mitosis is an important process, in which the replicated DNA content is properly allocated into two daughter cells. To ensure their genomic integrity, cells present an essential surveillance mechanism known as the spindle assembly checkpoint (SAC), which monitors the bipolar attachment of the mitotic spindle to chromosomes to prevent errors that would result in chromosome mis-segregation and aneuploidy. Multiple components of the nuclear pore complex (NPC), a gigantic protein complex that forms a channel through the nuclear envelope to allow nucleocytoplasmic exchange of macromolecules, were shown to be critical for faithful cell division and implicated in the regulation of different steps of the mitotic process, including kinetochore and spindle assembly as well as the SAC. In this review, we will describe current knowledge about the interconnection between the NPC and the SAC in an evolutional perspective, which primarily relies on the two mitotic checkpoint regulators, Mad1 and Mad2. We will further discuss the role of NPC constituents, the nucleoporins, in kinetochore and spindle assembly and the formation of the mitotic checkpoint complex during mitosis and interphase. PMID:26540075

  4. Giant elephantiasis neuromatosa in the setting of neurofibromatosis type 1: A case report

    PubMed Central

    PONTI, GIOVANNI; PELLACANI, GIOVANNI; MARTORANA, DAVIDE; MANDEL, VICTOR DESMOND; LOSCHI, PIETRO; POLLIO, ANNAMARIA; PECCHI, ANNARITA; DEALIS, CRISTINA; SEIDENARI, STEFANIA; TOMASI, ALDO

    2016-01-01

    Elephantiasis neuromatosa (EN) can arise from a plexiform neurofibroma of the superficial and deep nerves developing from a hyperproliferation of the perineural connective tissue infiltrating adjacent fat and muscles. To date, the clinical association between EN and neurofibromatosis type 1 (NF1) has been poorly defined, particularly with regard to the role of lymphatic alterations and the consequent lymphedema. The present study reports the clinical and biomolecular features of EN in a NF1 patient with the clear clinical diagnostic criteria of multiple cafè-au-lait macules, neurofibromas, EN, a positive family history and a novel NF1 germline c.1541_1542del mutation. Lymphoscintigraphy (LS) highlighted marked dermal backflow in the affected limb, hypertrophy of the ipsilateral inguinal and external iliac lymph nodes, and a bilateral lower limb lymph flow delay. These data support the hypothesis that an extensive hyperproliferative process involving perineural connective, limb soft tissues, bones and the lymphatic system can be responsible for EN in NF1 patients, on the basis of adipocyte metaplasia triggered by lymphostasis and lymphedema, and bone overgrowth and gigantism caused by chronic hyperemia. LS and magnetic resonance imaging can be efficacious tools in the diagnosis and clinical characterization of the early onset of the disease. PMID:27284375

  5. Tracing explosives in soil with transcriptional regulators of Pseudomonas putida evolved for responding to nitrotoluenes

    PubMed Central

    Garmendia, Junkal; De Las Heras, Aitor; Galvão, Teca Calcagno; De Lorenzo, Víctor

    2008-01-01

    Summary Although different biological approaches for detection of anti‐personnel mines and other unexploded ordnance (UXO) have been entertained, none of them has been rigorously documented thus far in the scientific literature. The industrial 2,4,6 trinitrotoluene (TNT) habitually employed in the manufacturing of mines is at all times tainted with a small but significant proportion of the more volatile 2,4 dinitrotoluene (2,4 DNT) and other nitroaromatic compounds. By using mutation‐prone PCR and DNA sequence shuffling we have evolved in vitro and selected in vivo variants of the effector recognition domain of the toluene‐responsive XylR regulator of the soil bacterium Pseudomonas putida that responds to mono‐, bi‐ and trinitro substituted toluenes. Re‐introduction of such variants in P. putida settled the transcriptional activity of the cognate promoters (Po and Pu) as a function of the presence of nitrotoluenes in the medium. When strains bearing transcriptional fusions to reporters with an optical output (luxAB, GFP) were spread on soil spotted with nitrotoluenes, the signal triggered by promoter activation allowed localization of the target compounds on the soil surface. Our data provide a proof of concept that non‐natural transcription factors evolved to respond to nitroaromatics can be engineered in soil bacteria and inoculated on a target site to pinpoint the presence of explosives. This approach thus opens new ways to tackle this gigantic humanitarian problem. PMID:21261843

  6. A High-velocity Cloud Impact Forming a Supershell in the Milky Way

    NASA Astrophysics Data System (ADS)

    Park, Geumsook; Koo, Bon-Chul; Kang, Ji-hyun; Gibson, Steven J.; Peek, J. E. G.; Douglas, Kevin A.; Korpela, Eric J.; Heiles, Carl E.

    2016-08-01

    Neutral atomic hydrogen (H i) gas in interstellar space is largely organized into filaments, loops, and shells, the most prominent of which are “supershells.” These gigantic structures, which require ≳ 3× {10}52 erg to form, are generally thought to be produced by either the explosion of multiple supernovae (SNe) in OB associations or, alternatively, by the impact of high-velocity clouds (HVCs) falling into the Galactic disk. Here, we report the detection of a kiloparsec (kpc)-size supershell in the outskirts of the Milky Way with the compact HVC 040 + 01‑282 (hereafter, CHVC040) at its geometrical center using the “Inner-Galaxy Arecibo L-band Feed Array” H i 21 cm survey data. The morphological and physical properties of both objects suggest that CHVC040, which is either a fragment of a nearby disrupted galaxy or a cloud that originated from an intergalactic accreting flow, collided with the disk ˜5 Myr ago to form the supershell. Our results show that some compact HVCs can survive their trip through the Galactic halo and inject energy and momentum into the Milky Way disk.

  7. No evidence for directional evolution of body mass in herbivorous theropod dinosaurs.

    PubMed

    Zanno, Lindsay E; Makovicky, Peter J

    2013-01-22

    The correlation between large body size and digestive efficiency has been hypothesized to have driven trends of increasing mass in herbivorous clades by means of directional selection. Yet, to date, few studies have investigated this relationship from a phylogenetic perspective, and none, to our knowledge, with regard to trophic shifts. Here, we reconstruct body mass in the three major subclades of non-avian theropod dinosaurs whose ecomorphology is correlated with extrinsic evidence of at least facultative herbivory in the fossil record--all of which also achieve relative gigantism (more than 3000 kg). Ordinary least-squares regressions on natural log-transformed mean mass recover significant correlations between increasing mass and geological time. However, tests for directional evolution in body mass find no support for a phylogenetic trend, instead favouring passive models of trait evolution. Cross-correlation of sympatric taxa from five localities in Asia reveals that environmental influences such as differential habitat sampling and/or taphonomic filtering affect the preserved record of dinosaurian body mass in the Cretaceous. Our results are congruent with studies documenting that behavioural and/or ecological factors may mitigate the benefit of increasing mass in extant taxa, and suggest that the hypothesis can be extrapolated to herbivorous lineages across geological time scales. PMID:23193135

  8. Using a smart phone application to measure high-energy radiation from thunderstorms

    NASA Astrophysics Data System (ADS)

    Bowers, G. S.; Smith, D. M.; Rexroad, W. Z.; Kelley, N. A.; Martinez-Mckinney, F.; Rubenstein, E. P.; Drukier, G.; Benes, G. N.

    2013-12-01

    Commercial airline flights and developing cell phone technologies present a burgeoning opportunity for the public to help investigate radiation from thunderstorms, including terrestrial gamma-ray flashes (TGFs), longer-lived gamma-ray glows, x-rays from lightning stepped leaders, and possible high-energy radiation, never yet observed, from blue jets, gigantic jets, and blue starters. GammaPix is a smartphone application from Image Insight, Inc. that uses the camera's CCD or CMOS sensor to identify and qualitatively assess threats related to gamma radioactivity, e.g., those caused by accidental exposure to radioactive material, high-altitude air travel, or acts of terrorism. A science-oriented version of the app is under development that will be publicized for use aboard commercial airline flights and on the ground in regions (like Japan in the wintertime) where thunderstorm charge centers come close to the ground. The primary goal of the project is to learn whether TGFs close to passenger aircraft and population centers on the ground occur often enough to create concern about radiation risk.

  9. Are We There Yet? Reliably Estimating the Completeness of Plant Genome Sequences.

    PubMed

    Veeckman, Elisabeth; Ruttink, Tom; Vandepoele, Klaas

    2016-08-01

    Genome sequencing is becoming cheaper and faster thanks to the introduction of next-generation sequencing techniques. Dozens of new plant genome sequences have been released in recent years, ranging from small to gigantic repeat-rich or polyploid genomes. Most genome projects have a dual purpose: delivering a contiguous, complete genome assembly and creating a full catalog of correctly predicted genes. Frequently, the completeness of a species' gene catalog is measured using a set of marker genes that are expected to be present. This expectation can be defined along an evolutionary gradient, ranging from highly conserved genes to species-specific genes. Large-scale population resequencing studies have revealed that gene space is fairly variable even between closely related individuals, which limits the definition of the expected gene space, and, consequently, the accuracy of estimates used to assess genome and gene space completeness. We argue that, based on the desired applications of a genome sequencing project, different completeness scores for the genome assembly and/or gene space should be determined. Using examples from several dicot and monocot genomes, we outline some pitfalls and recommendations regarding methods to estimate completeness during different steps of genome assembly and annotation. PMID:27512012

  10. Continuous Magnetoelectric Control in Multiferroic DyMnO3 Films with Twin-like Domains

    PubMed Central

    Lu, Chengliang; Deniz, Hakan; Li, Xiang; Liu, Jun-Ming; Cheong, Sang-Wook

    2016-01-01

    The magnetic control of ferroelectric polarization is currently a central topic in the multiferroic researches, owing to the related gigantic magnetoelectric coupling and fascinating physics. Although a bunch of novel magnetoelectric effect have been discovered in multiferroics of magnetic origin, the manipulation of polarization was found to be fundamentally determined by the microscopic origin in a certain multiferroic phase, hindering the development of unusual magnetoelectric control. Here, we report emergent magnetoelectric control in DyMnO3/Nb:SrTiO3 (001) films showing twin-like domain structure. Our results demonstrate interesting magnetically induced partial switch of polarization due to the coexistence of polarizations along both the a-axis and c-axis enabled by the twin-like domain structure in DyMnO3 films, despite the polarization-switch was conventionally believed to be a one-step event in the bulk counterpart. Moreover, a continuous and periodic control of macroscopic polarization by an in-plane rotating magnetic field is evidenced in the thin films. This distinctive magnetic manipulation of polarization is the consequence of the cooperative action of the twin-like domains and the dual magnetic origin of polarization, which promises additional applications using the magnetic control of ferroelectricity. PMID:26829899

  11. Inverse problem in ionospheric science: prediction of solar soft-X-ray spectrum from very low frequency radiosonde results

    NASA Astrophysics Data System (ADS)

    Palit, S.; Ray, S.; Chakrabarti, S. K.

    2016-05-01

    X-rays and gamma-rays from astronomical sources such as solar flares are mostly absorbed by the Earth's atmosphere. Resulting electron-ion production rate as a function of height depends on the intensity and wavelength of the injected spectrum and therefore the effects vary from one source to another. In other words, the ion density vs. altitude profile has the imprint of the incident photon spectrum. In this paper, we investigate whether we can invert the problem uniquely by deconvolution of the VLF amplitude signal to obtain the details of the injected spectrum. We find that it is possible to do this up to a certain accuracy. This leads us to the possibility of uninterrupted observation of X-ray photon spectra of solar flares that are often hindered by the restricted observation window of space satellites to avoid charge particle damages. Such continuous means of observation are essential in deriving information on time evolution of physical processes related to electron acceleration and interaction with plasma in solar atmosphere. Our method is useful to carry out a similar exercise to infer the spectra of more energetic events such as the Gamma Ray Bursts (GRBs), Soft Gamma-ray Repeaters (SGRs) etc., by probing even the lower part of the Earth's atmosphere. We thus show that to certain extent, the Earth's atmosphere could be used as a gigantic detector of relatively strong astronomical events.

  12. Prediction soft-X-ray spectrum of solar flares from Very Low Frequency observations: an inverse problem in ionospheric science

    NASA Astrophysics Data System (ADS)

    Palit, Sourav; Chakrabarti, Sandip Kumar; Ray, Suman

    2016-07-01

    Earth's lower ionosphere and upper atmosphere absorb X-rays and gamma-rays from astronomical sources such as solar flares, Short Gamma ray Repeaters (SGRs) or Gamma Ray Bursts (GRBs). The electron-ion production rates due to the ionization of such energetic photons at different heights depend on the intensity and wavelength of the injected spectrum and hence vary from one source to another. Obviously the ion density vs. altitude profile has the imprint of the incident photon spectrum. In this paper, we examine the possibility of inverting the electron density-height profiles uniquely by deconvolution of the VLF amplitude signal to obtain information on the injected spectrum. We have been able to reproduce the soft-X-ray part of the injected spectra from two different classes of solar flares with satisfactory accuracy. With the possibilities of probing even lower parts of the atmosphere, the method presented here is useful to carry out a similar exercise to infer the higher energy part of solar flare spectra and spectra of more energetic events such as the GRBs, SGRs etc. We show that to a certain accuracy, the Earth's atmosphere may be used as a gigantic detector of relatively strong ionizing extra-terrestrial events.

  13. Giant spin-driven ferroelectric polarization in TbMnO3 under high pressure.

    PubMed

    Aoyama, T; Yamauchi, K; Iyama, A; Picozzi, S; Shimizu, K; Kimura, T

    2014-01-01

    The recent research on multiferroics has provided solid evidence that the breaking of inversion symmetry by spin order can induce ferroelectric polarization P. This type of multiferroics, called spin-driven ferroelectrics, often show a gigantic change in P on application of a magnetic field B. However, their polarization (<~0.1 μC cm(-2)) is much smaller than that in conventional ferroelectrics (typically several to several tens of μC cm(-2)). Here we show that the application of external pressure to a representative spin-driven ferroelectric, TbMnO3, causes a flop of P and leads to the highest P (≈ 1.0 μC cm(-2)) among spin-driven ferroelectrics ever reported. We explain this behaviour in terms of a pressure-induced magnetoelectric phase transition, based on the results of density functional simulations. In the high-pressure phase, the application of B further enhances P over 1.8 μC cm(-2). This value is nearly an order of magnitude larger than those ever reported in spin-driven ferroelectrics. PMID:25215855

  14. Continuous Magnetoelectric Control in Multiferroic DyMnO3 Films with Twin-like Domains.

    PubMed

    Lu, Chengliang; Deniz, Hakan; Li, Xiang; Liu, Jun-Ming; Cheong, Sang-Wook

    2016-01-01

    The magnetic control of ferroelectric polarization is currently a central topic in the multiferroic researches, owing to the related gigantic magnetoelectric coupling and fascinating physics. Although a bunch of novel magnetoelectric effect have been discovered in multiferroics of magnetic origin, the manipulation of polarization was found to be fundamentally determined by the microscopic origin in a certain multiferroic phase, hindering the development of unusual magnetoelectric control. Here, we report emergent magnetoelectric control in DyMnO3/Nb:SrTiO3 (001) films showing twin-like domain structure. Our results demonstrate interesting magnetically induced partial switch of polarization due to the coexistence of polarizations along both the a-axis and c-axis enabled by the twin-like domain structure in DyMnO3 films, despite the polarization-switch was conventionally believed to be a one-step event in the bulk counterpart. Moreover, a continuous and periodic control of macroscopic polarization by an in-plane rotating magnetic field is evidenced in the thin films. This distinctive magnetic manipulation of polarization is the consequence of the cooperative action of the twin-like domains and the dual magnetic origin of polarization, which promises additional applications using the magnetic control of ferroelectricity. PMID:26829899

  15. Continuous Magnetoelectric Control in Multiferroic DyMnO3 Films with Twin-like Domains

    NASA Astrophysics Data System (ADS)

    Lu, Chengliang; Deniz, Hakan; Li, Xiang; Liu, Jun-Ming; Cheong, Sang-Wook

    2016-02-01

    The magnetic control of ferroelectric polarization is currently a central topic in the multiferroic researches, owing to the related gigantic magnetoelectric coupling and fascinating physics. Although a bunch of novel magnetoelectric effect have been discovered in multiferroics of magnetic origin, the manipulation of polarization was found to be fundamentally determined by the microscopic origin in a certain multiferroic phase, hindering the development of unusual magnetoelectric control. Here, we report emergent magnetoelectric control in DyMnO3/Nb:SrTiO3 (001) films showing twin-like domain structure. Our results demonstrate interesting magnetically induced partial switch of polarization due to the coexistence of polarizations along both the a-axis and c-axis enabled by the twin-like domain structure in DyMnO3 films, despite the polarization-switch was conventionally believed to be a one-step event in the bulk counterpart. Moreover, a continuous and periodic control of macroscopic polarization by an in-plane rotating magnetic field is evidenced in the thin films. This distinctive magnetic manipulation of polarization is the consequence of the cooperative action of the twin-like domains and the dual magnetic origin of polarization, which promises additional applications using the magnetic control of ferroelectricity.

  16. Wigner Crystal and Colossal Magnetoresistance in InSb Doped with Mn

    PubMed Central

    Obukhov, S. A.; Tozer, S. W.; Coniglio, W. A.

    2015-01-01

    We report magnetotransport investigation of nonmagnetic InSb single crystal doped with manganese at Mn concentration NMn ~ 1,5 × 1017 cm−3 in the temperature range T = 300 K–40 mK, magnetic field B = 0–25T and hydrostatic pressure P = 0–17 kbar. Resistivity saturation was observed in the absence of magnetic field at temperatures below 200 mK while applied increasing external magnetic field induced colossal drop of resistivity (by factor 104) at B ~ 4T with further gigantic resistivity increase (by factor 104) at 15T. Under pressure, P = 17 kbar, resistivity saturation temperature increased up to 1,2 K. Existing models are discussed in attempt to explain resistivity saturation, dramatic influence of magnetic field and pressure on resistivity with the focus on possible manifestation of three dimensional Wigner crystal formed in InSb by light electrons and heavy holes. PMID:26307952

  17. Northwestern Tharsis Latent Outflow Activity Mars

    NASA Technical Reports Server (NTRS)

    Dohm, J. M.; Anderson, R. C.; Baker, V. R.; Ferris, J. C.; Hare, T. M.; Strom, R. G.; Rudd, L.; Rice, J. W., Jr.; Scott, D. H.

    2000-01-01

    Previously defined outflow channels, which are indicated by relict landforms similar to those observed on Earth, signify ancient catastrophic flood events on Mars. These conspicuous geomorphic features are some of the most remarkable yet profound discoveries made by geologists to date. These outflow channels, which debouched tremendous volumes of water into topographic lows such as Chryse, Utopia, Elysium, and Hellas Planitiae, may represent the beginning of warmer and wetter climatic periods unlike the present-day cold and dry Mars. In addition to the previously identified outflow channels, observations permitted by the newly acquired Mars Orbiter Laser Altimeter (MOLA) data have revealed a system of gigantic valleys, referred to as the northwestern slope valleys (NSV), that are located to the northwest of a huge shield volcano, Arsia Mons, western hemisphere of Mars. These features generally correspond spatially to gravity lows similar to the easternmost, circum-Chryse outflow channel systems. Geologic investigations of the Tharsis region suggest that the large valley system pre-dates the construction of Arsia Mons and its extensive associated lava flows of mainly Late Hesperian and Amazonian age and coincides stratigraphically with the early development of the circum-Chryse outflow channel systems that debouch into Chryse Planitia. This newly identified system, the NSV, potentially signifies the largest flood event(s) ever recorded for the solar system. Additional information is contained in original extended abstract.

  18. Low-field magnetoelectric effect at room temperature

    NASA Astrophysics Data System (ADS)

    Kitagawa, Yutaro; Hiraoka, Yuji; Honda, Takashi; Ishikura, Taishi; Nakamura, Hiroyuki; Kimura, Tsuyoshi

    2010-10-01

    The discoveries of gigantic ferroelectric polarization in BiFeO3 (ref. 1) and ferroelectricity accompanied by a magnetic order in TbMnO3 (ref. 2) have renewed interest in research on magnetoelectric multiferroics, materials in which magnetic and ferroelectric orders coexist, from both fundamental and technological points of view. Among several different types of magnetoelectric multiferroic, magnetically induced ferroelectrics in which ferroelectricity is induced by complex magnetic orders, such as spiral orders, exhibit giant magnetoelectric effects, remarkable changes in electric polarization in response to a magnetic field. Many magnetically induced ferroelectrics showing the magnetoelectric effects have been found in the past several years. From a practical point of view, however, their magnetoelectric effects are useless because they operate only far below room temperature (for example, 28K in TbMnO3 (ref. 2) and 230K in CuO (ref. 11)). Furthermore, in most of them, the operating magnetic field is an order of tesla that is too high for practical applications. Here we report materials, Z-type hexaferrites, overcoming these problems on magnetically induced ferroelectrics. The best magnetoelectric properties were obtained for Sr3Co2Fe24O41 ceramics sintered in oxygen, which exhibit a low-field magnetoelectric effect at room temperature. Our result represents an important step towards practical device applications using the magnetoelectric effects.

  19. Water Relations of Chusquea ramosissima and Merostachys claussenii in Iguazu National Park, Argentina1

    PubMed Central

    Saha, Sonali; Holbrook, Noel M.; Montti, Lía; Goldstein, Guillermo; Cardinot, Gina Knust

    2009-01-01

    Bamboos are prominent components of many tropical ecosystems, yet little is known about the physiological mechanisms utilized by these gigantic forest grasses. Here, we present data on the water transport properties of Chusquea ramosissima and Merostachys claussenii, monocarpic bamboo grasses native to the subtropical Atlantic forests of Argentina. C. ramosissima and M. claussenii differed in their growth form and exhibited contrasting strategies of water transport. Maximum xylem hydraulic conductivity of C. ramosissima culms was 2-fold higher than that of M. claussenii. C. ramosissima cavitated at relatively high water potentials (50% loss of conductivity at ≥1 MPa), whereas M. claussenii was more drought tolerant (50% loss at ≤3 MPa). Both species exhibited significant loss of hydraulic conductivity during the day, which was reversed overnight due to the generation of root pressure. The photosynthetic capacities of both bamboo species, estimated based on electron transport rates, were moderate, reflecting both the large amount of leaf area supported by culms and diurnal loss of hydraulic conductivity due to cavitation. Leaf hydraulic conductance was also relatively low for both species, congruent with their modest photosynthetic capacities. Within its native range, C. ramosissima is highly invasive due to its ability to colonize and persist in both forest gaps and land cleared for agriculture. We propose that a highly vulnerable vasculature, coupled with diurnal root pressure and an allometry that allows substantial leaf area to be supported on relatively slender culms, are key traits contributing to the ecological success of C. ramosissima. PMID:19211704

  20. DNA Viruses: The Really Big Ones (Giruses)

    PubMed Central

    Van Etten, James L.; Lane, Leslie C.; Dunigan, David D.

    2010-01-01

    Viruses with genomes greater than 300 kb and up to 1200 kb are being discovered with increasing frequency. These large viruses (often called giruses) can encode up to 900 proteins and also many tRNAs. Consequently, these viruses have more protein-encoding genes than many bacteria, and the concept of small particle/small genome that once defined viruses is no longer valid. Giruses infect bacteria and animals although most of the recently discovered ones infect protists. Thus, genome gigantism is not restricted to a specific host or phylogenetic clade. To date, most of the giruses are associated with aqueous environments. Many of these large viruses (phycodnaviruses and Mimiviruses) probably have a common evolutionary ancestor with the poxviruses, iridoviruses, asfarviruses, ascoviruses, and a recently discovered Marseillevirus. One issue that is perhaps not appreciated by the microbiology community is that large viruses, even ones classified in the same family, can differ significantly in morphology, lifestyle, and genome structure. This review focuses on some of these differences rather than provides extensive details about individual viruses. PMID:20690825

  1. Developmental palaeontology in synapsids: the fossil record of ontogeny in mammals and their closest relatives.

    PubMed

    Sánchez-Villagra, Marcelo R

    2010-04-22

    The study of fossilized ontogenies in mammals is mostly restricted to postnatal and late stages of growth, but nevertheless can deliver great insights into life history and evolutionary mechanisms affecting all aspects of development. Fossils provide evidence of developmental plasticity determined by ecological factors, as when allometric relations are modified in species which invaded a new space with a very different selection regime. This is the case of dwarfing and gigantism evolution in islands. Skeletochronological studies are restricted to the examination of growth marks mostly in the cement and dentine of teeth and can provide absolute age estimates. These, together with dental replacement data considered in a phylogenetic context, provide life-history information such as maturation time and longevity. Palaeohistology and dental replacement data document the more or less gradual but also convergent evolution of mammalian growth features during early synapsid evolution. Adult phenotypes of extinct mammals can inform developmental processes by showing a combination of features or levels of integration unrecorded in living species. Some adult features such as vertebral number, easily recorded in fossils, provide indirect information about somitogenesis and hox-gene expression boundaries. Developmental palaeontology is relevant for the discourse of ecological developmental biology, an area of research where features of growth and variation are fundamental and accessible among fossil mammals. PMID:20071389

  2. A giant crocodile in the Dubois Collection from the Pleistocene of Kali Gedeh (Java).

    PubMed

    Delfino, Massimo; De Vos, John

    2014-03-01

    The fauna of the Pleistocene Homo-bearing sites of Java has been well known for more than a century. A recent revision of the crocodylian remains confirmed both the validity of Gavialis bengawanicus and the synonymization of Crocodylus ossifragus with C. siamensis. Here we report on a still unpublished crocodylian specimen collected by Eugene Dubois in the latest Early Pleistocene of Kali Gedeh that can be tentatively referred to the genus Crocodylus. The size of the specimen, the approximately 1 m long lower jaw in particular, indicated that this crocodile attained a total length of approximately 6 or 7 m. Along with specimens from the Plio-Pleistocene of Africa, this material provides evidence for gigantism in Crocodylus. It is not clear whether or not the 'temperature-size rule' applies to fossil crocodylians, but due to the growing interest in predicting future temperature-related size changes of the extant organisms, it would be interesting to study in detail the past reaction to temperature changes of crocodylians and other terrestrial ectothermic animals. PMID:24673759

  3. Martian outflow channels: How did their source aquifers form, and why did they drain so rapidly?

    PubMed Central

    Rodriguez, J. Alexis P.; Kargel, Jeffrey S.; Baker, Victor R.; Gulick, Virginia C.; Berman, Daniel C.; Fairén, Alberto G.; Linares, Rogelio; Zarroca, Mario; Yan, Jianguo; Miyamoto, Hideaki; Glines, Natalie

    2015-01-01

    Catastrophic floods generated ~3.2 Ga by rapid groundwater evacuation scoured the Solar System’s most voluminous channels, the southern circum-Chryse outflow channels. Based on Viking Orbiter data analysis, it was hypothesized that these outflows emanated from a global Hesperian cryosphere-confined aquifer that was infused by south polar meltwater infiltration into the planet’s upper crust. In this model, the outflow channels formed along zones of superlithostatic pressure generated by pronounced elevation differences around the Highland-Lowland Dichotomy Boundary. However, the restricted geographic location of the channels indicates that these conditions were not uniform Boundary. Furthermore, some outflow channel sources are too high to have been fed by south polar basal melting. Using more recent mission data, we argue that during the Late Noachian fluvial and glacial sediments were deposited into a clastic wedge within a paleo-basin located in the southern circum-Chryse region, which was then completely submerged under a primordial northern plains ocean. Subsequent Late Hesperian outflow channels were sourced from within these geologic materials and formed by gigantic groundwater outbursts driven by an elevated hydraulic head from the Valles Marineris region. Thus, our findings link the formation of the southern circum-Chryse outflow channels to ancient marine, glacial, and fluvial erosion and sedimentation. PMID:26346067

  4. Advanced Materials for Sustainable, Clean Energy Future

    SciTech Connect

    Yang, Zhenguo

    2009-04-01

    The current annual worldwide energy consumption stands at about 15 terawatts (TW, x1012 watts). Approximately 80% of it is supplied from fossil fuels: oil (34 %), coal (25 %), and natural gas (21 %). Biomass makes up 8% of the energy supply, nuclear energy accounts for 6.5 %, hydropower has a 2% share and other technologies such as wind and solar make up the rest. Even with aggressive conservation and new higher efficiency technology development, worldwide energy demand is predicted to double to 30 TW by 2050 and triple to 46 TW by the end of the century. Meanwhile oil and natural gas production is predicted to peak over the next few decades. Abundant coal reserves may maintain the current consumption level for longer period of time than the oil and gas. However, burning the fossil fuels leads to a serious environmental consequence by emitting gigantic amount of green house gases, particularly CO2 emissions which are widely considered as the primary contributor to global warming. Because of the concerns over the greenhouse gas emission, many countries, and even some states and cities in the US, have adopted regulations for limiting CO2 emissions. Along with increased CO2 regulations, is an emerging trend toward carbon “trading,” giving benefits to low “carbon footprint” industries, while making higher emitting industries purchase carbon “allowances”. There have been an increasing number of countries and states adopting the trade and cap systems.

  5. Martian outflow channels: How did their source aquifers form, and why did they drain so rapidly?

    NASA Astrophysics Data System (ADS)

    Rodriguez, J. Alexis P.; Kargel, Jeffrey S.; Baker, Victor R.; Gulick, Virginia C.; Berman, Daniel C.; Fairén, Alberto G.; Linares, Rogelio; Zarroca, Mario; Yan, Jianguo; Miyamoto, Hideaki; Glines, Natalie

    2015-09-01

    Catastrophic floods generated ~3.2 Ga by rapid groundwater evacuation scoured the Solar System’s most voluminous channels, the southern circum-Chryse outflow channels. Based on Viking Orbiter data analysis, it was hypothesized that these outflows emanated from a global Hesperian cryosphere-confined aquifer that was infused by south polar meltwater infiltration into the planet’s upper crust. In this model, the outflow channels formed along zones of superlithostatic pressure generated by pronounced elevation differences around the Highland-Lowland Dichotomy Boundary. However, the restricted geographic location of the channels indicates that these conditions were not uniform Boundary. Furthermore, some outflow channel sources are too high to have been fed by south polar basal melting. Using more recent mission data, we argue that during the Late Noachian fluvial and glacial sediments were deposited into a clastic wedge within a paleo-basin located in the southern circum-Chryse region, which was then completely submerged under a primordial northern plains ocean. Subsequent Late Hesperian outflow channels were sourced from within these geologic materials and formed by gigantic groundwater outbursts driven by an elevated hydraulic head from the Valles Marineris region. Thus, our findings link the formation of the southern circum-Chryse outflow channels to ancient marine, glacial, and fluvial erosion and sedimentation.

  6. The Role of Theory and Modeling in the Development of Materials for Fusion Energy

    NASA Astrophysics Data System (ADS)

    Ghoniem, Nasr M.

    The environmental and operational conditions of First Wall/ Blanket (FW/B) structural materials in fusion energy systems are undoubtedly amongst the harshest in any technological application. These materials must operate reliably for extended periods of times without maintenance or repair. They must withstand the assaults of high particle and heat fluxes, as well as significant thermal and mechanical forces. Rival conditions have not been experienced in other technologies, with possible exceptions in aerospace and defense applications. Moreover, the most significant dilemma here is that the actual operational environment cannot be experimentally established today, with all of the synergistic considerations of neutron spectrum, radiation dose, heat and particle flux, and gigantic FW/B module sizes. Because of these considerations, we may rely on a purely empirical and incremental boot-strapping approach (as in most human developments so far), or an approach based on data generation from non prototypical setups (e.g., small samples, fission spectra, ion irradiation, etc.), or a theoretical/computational methodology. The first approach would have been the most direct had it not been for the unacceptable risks in the construction of successively larger and more powerful fusion machines, learning from one how to do it better for the next. The last approach (theory and modeling alone) is not a very viable option, because we are not now in a position to predict materials behavior in all its aspects from purely theoretical grounds.

  7. Chlorella minutissima--a promising fuel alga for cultivation in municipal wastewaters.

    PubMed

    Bhatnagar, Ashish; Bhatnagar, Monica; Chinnasamy, Senthil; Das, K C

    2010-05-01

    It is imperative to slash the cost of algal oil to less than $50 bbl(-1) for successful algal biofuel production. Use of municipal wastewater for algal cultivation could obviate the need for freshwater and the nutrients--N and P. It would also add CO2 through bacterial activity. Chlorella minutissima Fott et Nova dominated the entire phycoflora year around and through each stage of the wastewater treatment at the oxidation pond system of Wazirabad (Delhi) in India. The ability to grow so profusely in such varied and contrasting situations made this alga unique. Besides pollution tolerance, it grew heterotrophically in dark under acidic conditions and as a mixotroph in presence of light over a range of organic C substrates. It could utilize both ammoniacal and nitrate nitrogen, survived anaerobicity, 5% NaCl and-10 bar of osmotic stress. C. minutissima grew at pH 4-11 and raised the pH set initially by 1 to 3 units in 7.5 h. It showed gigantism and largely kept afloat in presence of utilizable organic carbon, while flocculated in mineral medium and on aging. The alga also possessed potential for biofuel production. The studied parameters indicate why C. minutissima was a potential biomass builder in municipal sewage and could be used to determine which other alga(e) may serve the purpose. PMID:19882116

  8. New color images of transient luminous events from dedicated observations on the International Space Station

    NASA Astrophysics Data System (ADS)

    Yair, Yoav; Rubanenko, Lior; Mezuman, Keren; Elhalel, Gal; Pariente, Meidad; Glickman-Pariente, Maya; Ziv, Baruch; Takahashi, Yukihiro; Inoue, Tomohiro

    2013-09-01

    During July-August 2011, Expedition 28/29 JAXA astronaut Satoshi Furukawa conducted TLE observations from the International Space Station in conjunction with the “Cosmic Shore” program produced by NHK. An EMCCD normal video-rate color TV camera was used to conduct directed observations from the Earth-pointing Cupola module. The target selection was based on the methodology developed for the MEIDEX sprite campaign on board the space shuttle Columbia in January 2003 (Ziv et al., 2004). The observation geometry was pre-determined and uploaded daily to the ISS with pointing options to limb, oblique or nadir, based on the predicted location of the storm with regards to the ISS. The pointing angle was rotated in real-time according to visual eyesight by the astronaut. We present results of 10 confirmed TLEs: 8 sprites, 1 sprite halo and 1 gigantic jet, out of <2 h of video. Sprites tend to appear in a single frame simultaneously with maximum lightning brightness. Unique images (a) from nadir of a sprite horizontally displaced form the lightning light and (b) from the oblique view of a sprite halo, enable the calculation of dimensions and volumes occupied by these TLEs. Since time stamping on the ISS images was accurate within 1 s, matching with ELF and WWLLN data for the parent lightning location is limited. Nevertheless, the results prove that the ISS is an ideal platform for lightning and TLE observations, and careful operational procedures greatly enhance the value of observation time.

  9. ADELE sensitivity to high-energy radiation from transient luminous events during the Hurricane and Severe Storm Sentinels campaigns

    NASA Astrophysics Data System (ADS)

    Bowers, G.; Smith, D. M.; Dwyer, J. R.; Cummer, S. A.; Martinez-Mckinney, F.; Kelley, N. A.; Harris, C. B.; Buzbee, P.

    2012-12-01

    In the summers of 2013 and 2014, UCSC will fly the Airborne Detector for Energetic Lightning Emissions (ADELE) instrument on board one of the Global Hawk aircraft of the NASA Hurricane and Severe Storm Sentinels (HS3) campaign over storms in the Atlantic. In addition to Terrestrial Gamma-ray Flashes (TGFs), which have been observed at gamma-ray energies by satellites such as RHESSI and FERMI, ADELE will also search for high-energy radiation from Transient Luminous Events (TLEs, i.e. elves, gigantic jets, blue jets, sprites, and sprite halos). High-energy radiation is plausible as a byproduct of stepped leaders in jets, streamers in sprites, and acceleration of electrons in the electromagnetic pulse (EMP) that produces elves. Because ADELE will fly at low altitudes, the intensity of radiation from these events could be orders of magnitude higher at ADELE than at satellites in low earth orbit. We will consider the high energy spectra that might be produced by TLEs and estimate to what extent these phenomena can be observed by ADELE on HS3.

  10. Effect of Previous Milling of Precursors on Magnetoelectric Effect in Multiferroic {Bi5Ti3FeO_{15}} Ceramic

    NASA Astrophysics Data System (ADS)

    Dercz, J.; Bartkowska, J.; Dercz, G.; Stoch, P.; Łukasik, M.

    2013-04-01

    Bi5Ti3FeO_{15} magnetoelectric (ME) ceramics have been synthesized and investigated. The ME effect can be described as an induced electric polarization under an external magnetic field or an induced magnetization under an external electric field. The materials in the ME effect are called ME materials, and they are considered to be a kind of new promising materials for sensors, processors, actuators, and memory systems. Multiferroics, the materials in which both ferromagnetism and ferroelectricity can coexist, are the prospective candidates which can potentially host the gigantic ME effect. Bi5Ti3FeO_{15}, an Aurivillius compound, was synthesized by sintering a mixture of Bi2O3, Fe2O3, and TiO2 oxides. The precursor materials were prepared in a high-energy attritorial mill for (1, 5, and 10) h. The orthorhombic Bi5Ti3FeO_{15} ceramics were obtained by a solid-state reaction process at 1313 K. The ME voltage coefficient (α _ME) was measured using the dynamic lock-in method. The highest ME voltage coefficient (α _ME = 8.28 mV{\\cdot } cm^{-1}{\\cdot } Oe^{-1}) is obtained for the sample milled for 1 h at H_DC = 4 Oe (1 Oe = 79.58 A{\\cdot }m^{-1}).

  11. Giant streaming currents measured in a gold sputtered glass microchannel array

    NASA Astrophysics Data System (ADS)

    Mansouri, Abraham; Kostiuk, Larry W.

    2016-02-01

    Pressure-driven-flow of a dilute aqueous solution in a microchannel with charged walls generates streaming currents (ionic current) and streaming potentials across the microchannel. While generation of streaming currents can be performed in network of parallel circular microchannels or unstructured porous media, accurate measurements of such currents remain a challenge. In this study a gigantic amount of streaming current was successfully generated and measured using a glass microchannel array with special gold sputtered coatings on both its ends. Streaming current as high as 0.7 mA was obtained with moderate pressure drop (124 kPa) across the glass microchannel array that consists of approximately 11 250 000 parallel microchannels with radii of 2.5 μm. Higher streaming currents are also possible to generate (scaled to 142 μA/cm2 of frontal area at a flow rate of 12 cm3/s) with potential applications in surface charge characterizations and electrokinetic power generation. In addition, apparent ζ potential of glass microchannel array surface was estimated with the aid of streaming current data and Levine-Olivare theories and an apparent ζ potential of -65 mV (0 M KCl, κa = 8) is reported.

  12. Reduced genetic variation in the Japanese giant salamander, Andrias japonicus (Amphibia: Caudata).

    PubMed

    Matsui, Masafumi; Tominaga, Atsushi; Liu, Wan-zhao; Tanaka-Ueno, Tomoko

    2008-10-01

    The phylogenetic relationships among 46 samples from 27 populations of the Japanese giant salamander, Andriasjaponicus and its congener, A. davidianus from China was investigated, using 3664 bp sequences of the mitochondrial genes NADH1, NADH3, cyt b and CR, partial NADH6 and intervening genes. In phylogenetic trees constructed by MP, ML, and Bayesian methods, the family Cryptobranchidae and the genus Andrias both form monophyletic groups. Japanese A. japonicus and Chinese A. davidianus are sister taxa and can be regarded as separate species despite a small degree of genetic differentiation. Andriasjaponicus is divided into central and western clades, but the phylogenetic relationships within the latter clade are unresolved. As previously reported from allozyme analyses, A. japonicus exhibits little genetic differentiation, in strong contrast to salamanders of the genus Hynobius with which their distributions overlap. This reduced genetic variability in A. japonicus is attributable to a unique mating system of polygyny, delayed sexual maturity, notable longevity, life in a stable aquatic environment, and gigantism, as well as bottleneck effects following habitat fragmentation and extinction of local populations during Quaternary glaciations. The species is thus susceptible to extinction by potential environmental fluctuations, and requires extensive conservation measures. PMID:18723097

  13. Ferroelectricity with Ferromagnetic Moment in Orthoferrites

    NASA Astrophysics Data System (ADS)

    Tokunaga, Yusuke

    2010-03-01

    Exotic multiferroics with gigantic magnetoelectric (ME) coupling have recently been attracting broad interests from the viewpoints of both fundamental physics and possible technological application to next-generation spintronic devices. To attain a strong ME coupling, it would be preferable that the ferroelectric order is induced by the magnetic order. Nevertheless, the magnetically induced ferroelectric state with the spontaneous ferromagnetic moment is still quite rare apart from a few conical-spin multiferroics. To further explore multiferroic materials with both the strong ME coupling and spontaneous magnetization, we focused on materials with magnetic structures other than conical structure. In this talk we present that the most orthodox perovskite ferrite systems DyFeO3 and GdFeO3 have ``ferromagnetic-ferroelectric,'' i.e., genuinely multiferroic states in which weak ferromagnetic moment is induced by Dzyaloshinskii-Moriya interaction working on Fe spins and electric polarization originates from the striction due to symmetric exchange interaction between Fe and Dy (Gd) spins [1] [2]. Both materials showed large electric polarization (>0.1 μC/cm^2) and strong ME coupling. In addition, we succeeded in mutual control of magnetization and polarization with electric- and magnetic-fields in GdFeO3, and attributed the controllability to novel, composite domain wall structure. [4pt] [1] Y. Tokunaga et al., Phys. Rev. Lett. 101, 097205 (2008). [0pt] [2] Y. Tokunaga et al., Nature Mater. 8, 558 (2009).

  14. Noachian Faulting: What Do Faults Tell Us About the Tectonic History of Tharsis?

    NASA Technical Reports Server (NTRS)

    Anderson, R. C.; Dohm, J. M.

    2001-01-01

    The western hemisphere of Mars is dominated by the formation of Tharsis, which is an enormous high-standing region (roughly 25% of the surface area of the planet) capped by volcanics, including the solar system's largest shield volcanoes. Tharsis is surrounded by an enormous radiating system of grabens and a circumferential system of wrinkle ridges that extends over the entire western hemisphere of Mars. This region is perhaps the largest and most long lived tectonic and volcanic province of any of the terrestrial planets with a well-preserved history of magmatic-driven activity that began in the Noachian and has lasted throughout Martian geologic time. Tharsis and the surrounding regions comprise numerous components, including volcanic constructs of varying sizes and extensive lava flow fields, large igneous plateaus, fault and ridge systems of varying extent and relative age of formation, gigantic outflow channel systems, vast system of canyons, and local and regional centers of tectonic activity. Many of these centers are interpreted to be the result of magmatic-related activity, including uplift, faulting, dike emplacement, volcanism, and local hydrothermal activity. Below we present a summary of our work for Tharsis focusing primarily on the earliest stage of development, the Noachian period. Here we hone in on the early centers and how they relate to the early development of the Tharsis Magmatic Complex (TMC).

  15. Solitary ganglioneuromatosis of the descending colon, presenting as giant retroperitoneal tumour.

    PubMed

    Mateş, In; Iosif, C; Dinu, D; Constantinoiu, S

    2013-01-01

    Ganglioneuroma (GN) is a benign neoplasia of the autonomous nervous system, colonic GN is uncommon in adults. There are three subgroups: polypoid GN, ganglioneuromatous polyposis and diffuse ganglioneuromatosis. Ganglioneuromatosis is highly-associated to neurofibromatosis type 1 (NF1) and multiple endocrine neoplasia type 2b (MEN2B). A 68-year-old female, with a discrete retarded emission of stools, was admitted for a large tumor in the left flank; CT scan, urography and barium enema demonstrated a large retroperitoneal mass, presumed as sarcoma. Open surgery discovered a 16 10 11 cm solid and encapsulated tumor, attached to the retroperitoneal descending colon, with no macroscopic mucosal involvement; the pathologic diagnosis of the resected specimen (en-bloc tumorectomy with limited colectomy) was intramural colonic ganglio-neuromatosis. Anamnesis, physical examination and complete endoscopic explorations showed no evidence of personal bearing or familial aggregation of genetic syndromes. In adults, association of transmural ganglioneuromatosis to NF1 or MEN2B is not mandatory; presentation often mimics obstructive carcinoma and positive diagnosis is provided by pathological examination of the resected specimen. In this peculiar case, the loose tissue of the retroperitoneal space favoured a slow development of intramural ganglioneuromatosis, presenting as a gigantic retroperitoneal mass with no radiological evidence of its colonic origin. PMID:23958108

  16. Mitochondrial fission is an acute and adaptive response in injured motor neurons

    PubMed Central

    Kiryu-Seo, Sumiko; Tamada, Hiromi; Kato, Yukina; Yasuda, Katsura; Ishihara, Naotada; Nomura, Masatoshi; Mihara, Katsuyoshi; Kiyama, Hiroshi

    2016-01-01

    Successful recovery from neuronal damage requires a huge energy supply, which is provided by mitochondria. However, the physiological relevance of mitochondrial dynamics in damaged neurons in vivo is poorly understood. To address this issue, we established unique bacterial artificial chromosome transgenic (BAC Tg) mice, which develop and function normally, but in which neuronal injury induces labelling of mitochondria with green fluorescent protein (GFP) and expression of cre recombinase. GFP-labelled mitochondria in BAC Tg mice appear shorter in regenerating motor axons soon after nerve injury compared with mitochondria in non-injured axons, suggesting the importance of increased mitochondrial fission during the early phase of nerve regeneration. Crossing the BAC Tg mice with mice carrying a floxed dynamin-related protein 1 gene (Drp1), which is necessary for mitochondrial fission, ablates mitochondrial fission specifically in injured neurons. Injury-induced Drp1-deficient motor neurons show elongated or abnormally gigantic mitochondria, which have impaired membrane potential and axonal transport velocity during the early phase after injury, and eventually promote neuronal death. Our in vivo data suggest that acute and prominent mitochondrial fission during the early stage after nerve injury is an adaptive response and is involved in the maintenance of mitochondrial and neuronal integrity to prevent neurodegeneration. PMID:27319806

  17. Solar Electricity and Solar Fuels: Status and Perspectives in the Context of the Energy Transition.

    PubMed

    Armaroli, Nicola; Balzani, Vincenzo

    2016-01-01

    The energy transition from fossil fuels to renewables is already ongoing, but it will be a long and difficult process because the energy system is a gigantic and complex machine. Key renewable energy production data show the remarkable growth of solar electricity technologies and indicate that crystalline silicon photovoltaics (PV) and wind turbines are the workhorses of the first wave of renewable energy deployment on the TW scale around the globe. The other PV alternatives (e.g., copper/indium/gallium/selenide (CIGS) or CdTe), along with other less mature options, are critically analyzed. As far as fuels are concerned, the situation is significantly more complex because making chemicals with sunshine is far more complicated than generating electric current. The prime solar artificial fuel is molecular hydrogen, which is characterized by an excellent combination of chemical and physical properties. The routes to make it from solar energy (photoelectrochemical cells (PEC), dye-sensitized photoelectrochemical cells (DSPEC), PV electrolyzers) and then synthetic liquid fuels are presented, with discussion on economic aspects. The interconversion between electricity and hydrogen, two energy carriers directly produced by sunlight, will be a key tool to distribute renewable energies with the highest flexibility. The discussion takes into account two concepts that are often overlooked: the energy return on investment (EROI) and the limited availability of natural resources-particularly minerals-which are needed to manufacture energy converters and storage devices on a multi-TW scale. PMID:26584653

  18. Giant blocks in the South Kona landslide, Hawaii

    USGS Publications Warehouse

    Moore, J.G.; Bryan, W.B.; Beeson, M.H.; Normark, W.R.

    1995-01-01

    A large field of blocky sea-floor hills, up to 10km long and 500 high, are gigantic slide blocks derived from the west flank of Mauna Loa volcano on the island of Hawaii. These megablocks are embedded in the toe of the south Kona landslide, which extends ~80km seaward from the present coastline to depths of nearly 5km. A 10-15km-wide belt of numerous, smaller, 1-3 km-long slide blocks separates the area of giant blocks from two submarine benches at depths of 2600 and 3700m depth that terminate seaward 20 to 30km from the shoreline. Similar giant blocks are found on several other major submarine Hawaiian landslides, including those north of Oahu and Molokai, but the South Kona blocks are the first to be examined in detail using high-resolution bathymetry, dredging, and submersible diving. Dredging of two of the giant blocks brought up pillowed tholeiitic lava. Megablocks were carried by a late Pleistocene giant landslide 40-80km west from the ancestral shoreline of Mauna Loa volcano before growth of the midslope benches by later slump movement. -from Authors

  19. Galaxy Mass Assembly with VLT & HST and lessons for E-ELT/MOSAIC

    NASA Astrophysics Data System (ADS)

    Hammer, François; Flores, Hector; Puech, Mathieu

    2015-02-01

    The fraction of distant disks and mergers is still debated, while 3D-spectroscopy is revolutionizing the field. However its limited spatial resolution imposes a complimentary HST imagery and a robust analysis procedure. When applied to observations of IMAGES galaxies at z = 0.4-0.8, it reveals that half of the spiral progenitors were in a merger phase, 6 billion year ago. The excellent correspondence between methodologically-based classifications of morphologies and kinematics definitively probes a violent origin of disk galaxies as proposed by Hammer et al. (2005). Examination of nearby galaxy outskirts reveals fossil imprints of such ancient merger events, under the form of well organized stellar streams. Perhaps our neighbor, M31, is the best illustration of an ancient merger, which modeling in 2010 leads to predict the gigantic plane of satellites discovered by Ibata et al. (2013). There are still a lot of discoveries to be done until the ELT era, which will open an avenue for detailed and accurate 3D-spectroscopy of galaxies from the earliest epochs to the present.

  20. Lite-Sat's for specific communication tasks

    NASA Astrophysics Data System (ADS)

    Dodel, H.; Riedl, Ch.

    1991-10-01

    Since 1957 communications satellites have shown an ascending trend towards ever more gigantic platforms. Now this trend is reversing. Intelsat 7 falls short of its predecessor. At the same time lightsats, smallsat's, and minisat's enter the scene. The scientific community, environmental research, and commercial users alike have begun to employ small spacecraft for specific communications tasks. Potential services that smaller satellites could serve adequately or even uniquely are considered and the market place and the market potential for the lightsats is depicted. An overview of the launch opportunities for these vehicles is given. The following questions are considered: how do smaller spacecraft perform in quality of manufacturing? What is the quality of manufacturing of their launchers and the reliability of the launches? Are the big platforms doomed? How reliable is commercial operation of the vehicle? What is the design maturity of spacecraft and launcher? What are the economics of the satellite production, the production of the launcher and the operational life of the satellite compared to conventional platforms? What is the intrinsic cost reduction potential of smaller satellites and economies of scale of a fleet of small satellites? How do efforts for scrapping compare for small spacecraft and, say, the 18 ton platform?

  1. Cell size versus body size in geophilomorph centipedes.

    PubMed

    Moretto, Marco; Minelli, Alessandro; Fusco, Giuseppe

    2015-04-01

    Variation in animal body size is the result of a complex interplay between variation in cell number and cell size, but the latter has seldom been considered in wide-ranging comparative studies, although distinct patterns of variation have been described in the evolution of different lineages. We investigated the correlation between epidermal cell size and body size in a sample of 29 geophilomorph centipede species, representative of a wide range of body sizes, from 6 mm dwarf species to gigantic species more than 200 mm long, exploiting the marks of epidermal cells on the overlying cuticle in the form of micro-sculptures called scutes. We found conspicuous and significant variation in average scute area, both between suprageneric taxa and between genera, while the within-species range of variation is comparatively small. This supports the view that the average epidermal cell size is to some extent taxon specific. However, regression analyses show that neither body size nor the number of leg-bearing segments explain this variation, which suggests that cell size is not an usual target of change for body size evolution in this group of arthropods, although there is evidence of its correlation with other morphological variables, like cuticle thickness. Scute sizes of miniaturized geophilomorph species are well within the range of the lineage to which the species belong, suggesting recent evolutionary transitions to smaller body size. PMID:25809818

  2. Cell size versus body size in geophilomorph centipedes

    NASA Astrophysics Data System (ADS)

    Moretto, Marco; Minelli, Alessandro; Fusco, Giuseppe

    2015-04-01

    Variation in animal body size is the result of a complex interplay between variation in cell number and cell size, but the latter has seldom been considered in wide-ranging comparative studies, although distinct patterns of variation have been described in the evolution of different lineages. We investigated the correlation between epidermal cell size and body size in a sample of 29 geophilomorph centipede species, representative of a wide range of body sizes, from 6 mm dwarf species to gigantic species more than 200 mm long, exploiting the marks of epidermal cells on the overlying cuticle in the form of micro-sculptures called scutes. We found conspicuous and significant variation in average scute area, both between suprageneric taxa and between genera, while the within-species range of variation is comparatively small. This supports the view that the average epidermal cell size is to some extent taxon specific. However, regression analyses show that neither body size nor the number of leg-bearing segments explain this variation, which suggests that cell size is not an usual target of change for body size evolution in this group of arthropods, although there is evidence of its correlation with other morphological variables, like cuticle thickness. Scute sizes of miniaturized geophilomorph species are well within the range of the lineage to which the species belong, suggesting recent evolutionary transitions to smaller body size.

  3. Peculiar macrophagous adaptations in a new Cretaceous pliosaurid.

    PubMed

    Fischer, Valentin; Arkhangelsky, Maxim S; Stenshin, Ilya M; Uspensky, Gleb N; Zverkov, Nikolay G; Benson, Roger B J

    2015-12-01

    During the Middle and Late Jurassic, pliosaurid plesiosaurs evolved gigantic body size and a series of craniodental adaptations that have been linked to the occupation of an apex predator niche. Cretaceous pliosaurids (i.e. Brachaucheninae) depart from this morphology, being slightly smaller and lacking the macrophagous adaptations seen in earlier forms. However, the fossil record of Early Cretaceous pliosaurids is poor, concealing the evolution and ecological diversity of the group. Here, we report a new pliosaurid from the Late Hauterivian (Early Cretaceous) of Russia. Phylogenetic analyses using reduced consensus methods recover it as the basalmost brachauchenine. This pliosaurid is smaller than other derived pliosaurids, has tooth alveoli clustered in pairs and possesses trihedral teeth with complex serrated carinae. Maximum-likelihood ancestral state reconstruction suggests early brachauchenines retained trihedral teeth from their ancestors, but modified this feature in a unique way, convergent with macrophagous archosaurs or sphenacodontoids. Our findings indicate that Early Cretaceous marine reptile teeth with serrated carinae cannot be unequivocally assigned to metriorhynchoid crocodylomorphs. Furthermore, they extend the known diversity of dental adaptations seen in Sauropterygia, the longest lived clade of marine tetrapods. PMID:27019740

  4. Creating the brain and interacting with the brain: an integrated approach to understanding the brain

    PubMed Central

    Morimoto, Jun; Kawato, Mitsuo

    2015-01-01

    In the past two decades, brain science and robotics have made gigantic advances in their own fields, and their interactions have generated several interdisciplinary research fields. First, in the ‘understanding the brain by creating the brain’ approach, computational neuroscience models have been applied to many robotics problems. Second, such brain-motivated fields as cognitive robotics and developmental robotics have emerged as interdisciplinary areas among robotics, neuroscience and cognitive science with special emphasis on humanoid robots. Third, in brain–machine interface research, a brain and a robot are mutually connected within a closed loop. In this paper, we review the theoretical backgrounds of these three interdisciplinary fields and their recent progress. Then, we introduce recent efforts to reintegrate these research fields into a coherent perspective and propose a new direction that integrates brain science and robotics where the decoding of information from the brain, robot control based on the decoded information and multimodal feedback to the brain from the robot are carried out in real time and in a closed loop. PMID:25589568

  5. Slime mould processors, logic gates and sensors.

    PubMed

    Adamatzky, A

    2015-07-28

    A heterotic, or hybrid, computation implies that two or more substrates of different physical nature are merged into a single device with indistinguishable parts. These hybrid devices then undertake coherent acts on programmable and sensible processing of information. We study the potential of heterotic computers using slime mould acting under the guidance of chemical, mechanical and optical stimuli. Plasmodium of acellular slime mould Physarum polycephalum is a gigantic single cell visible to the unaided eye. The cell shows a rich spectrum of behavioural morphological patterns in response to changing environmental conditions. Given data represented by chemical or physical stimuli, we can employ and modify the behaviour of the slime mould to make it solve a range of computing and sensing tasks. We overview results of laboratory experimental studies on prototyping of the slime mould morphological processors for approximation of Voronoi diagrams, planar shapes and solving mazes, and discuss logic gates implemented via collision of active growing zones and tactile responses of P. polycephalum. We also overview a range of electronic components--memristor, chemical, tactile and colour sensors-made of the slime mould. PMID:26078344

  6. Sinbase: an integrated database to study genomics, genetics and comparative genomics in Sesamum indicum.

    PubMed

    Wang, Linhai; Yu, Jingyin; Li, Donghua; Zhang, Xiurong

    2015-01-01

    Sesame (Sesamum indicum L.) is an ancient and important oilseed crop grown widely in tropical and subtropical areas. It belongs to the gigantic order Lamiales, which includes many well-known or economically important species, such as olive (Olea europaea), leonurus (Leonurus japonicus) and lavender (Lavandula spica), many of which have important pharmacological properties. Despite their importance, genetic and genomic analyses on these species have been insufficient due to a lack of reference genome information. The now available S. indicum genome will provide an unprecedented opportunity for studying both S. indicum genetic traits and comparative genomics. To deliver S. indicum genomic information to the worldwide research community, we designed Sinbase, a web-based database with comprehensive sesame genomic, genetic and comparative genomic information. Sinbase includes sequences of assembled sesame pseudomolecular chromosomes, protein-coding genes (27,148), transposable elements (372,167) and non-coding RNAs (1,748). In particular, Sinbase provides unique and valuable information on colinear regions with various plant genomes, including Arabidopsis thaliana, Glycine max, Vitis vinifera and Solanum lycopersicum. Sinbase also provides a useful search function and data mining tools, including a keyword search and local BLAST service. Sinbase will be updated regularly with new features, improvements to genome annotation and new genomic sequences, and is freely accessible at http://ocri-genomics.org/Sinbase/. PMID:25480115

  7. Fermi surfaces, spin-mixing parameter, and colossal anisotropy of spin relaxation in transition metals from ab initio theory

    NASA Astrophysics Data System (ADS)

    Zimmermann, Bernd; Mavropoulos, Phivos; Long, Nguyen H.; Gerhorst, Christian-Roman; Blügel, Stefan; Mokrousov, Yuriy

    2016-04-01

    The Fermi surfaces and Elliott-Yafet spin-mixing parameter (EYP) of several elemental metals are studied by ab initio calculations. We focus first on the anisotropy of the EYP as a function of the direction of the spin-quantization axis [B. Zimmermann et al., Phys. Rev. Lett. 109, 236603 (2012), 10.1103/PhysRevLett.109.236603]. We analyze in detail the origin of the gigantic anisotropy in 5 d hcp metals as compared to 5 d cubic metals by band structure calculations and discuss the stability of our results against an applied magnetic field. We further present calculations of light (4 d and 3 d ) hcp crystals, where we find a huge increase of the EYP anisotropy, reaching colossal values as large as 6000 % in hcp Ti. We attribute these findings to the reduced strength of spin-orbit coupling, which promotes the anisotropic spin-flip hot loops at the Fermi surface. In order to conduct these investigations, we developed an adapted tetrahedron-based method for the precise calculation of Fermi surfaces of complicated shape and accurate Fermi-surface integrals within the full-potential relativistic Korringa-Kohn-Rostoker Green function method.

  8. Rapid conduction and the evolution of giant axons and myelinated fibers.

    PubMed

    Hartline, D K; Colman, D R

    2007-01-01

    Nervous systems have evolved two basic mechanisms for increasing the conduction speed of the electrical impulse. The first is through axon gigantism: using axons several times larger in diameter than the norm for other large axons, as for example in the well-known case of the squid giant axon. The second is through encasing axons in helical or concentrically wrapped multilamellar sheets of insulating plasma membrane--the myelin sheath. Each mechanism, alone or in combination, is employed in nervous systems of many taxa, both vertebrate and invertebrate. Myelin is a unique way to increase conduction speeds along axons of relatively small caliber. It seems to have arisen independently in evolution several times in vertebrates, annelids and crustacea. Myelinated nerves, regardless of their source, have in common a multilamellar membrane wrapping, and long myelinated segments interspersed with 'nodal' loci where the myelin terminates and the nerve impulse propagates along the axon by 'saltatory' conduction. For all of the differences in detail among the morphologies and biochemistries of the sheath in the different myelinated animal classes, the function is remarkably universal. PMID:17208176

  9. Are We There Yet? Reliably Estimating the Completeness of Plant Genome Sequences[OPEN

    PubMed Central

    2016-01-01

    Genome sequencing is becoming cheaper and faster thanks to the introduction of next-generation sequencing techniques. Dozens of new plant genome sequences have been released in recent years, ranging from small to gigantic repeat-rich or polyploid genomes. Most genome projects have a dual purpose: delivering a contiguous, complete genome assembly and creating a full catalog of correctly predicted genes. Frequently, the completeness of a species’ gene catalog is measured using a set of marker genes that are expected to be present. This expectation can be defined along an evolutionary gradient, ranging from highly conserved genes to species-specific genes. Large-scale population resequencing studies have revealed that gene space is fairly variable even between closely related individuals, which limits the definition of the expected gene space, and, consequently, the accuracy of estimates used to assess genome and gene space completeness. We argue that, based on the desired applications of a genome sequencing project, different completeness scores for the genome assembly and/or gene space should be determined. Using examples from several dicot and monocot genomes, we outline some pitfalls and recommendations regarding methods to estimate completeness during different steps of genome assembly and annotation. PMID:27512012

  10. Space Weather: The Solar Perspective

    NASA Astrophysics Data System (ADS)

    Schwenn, Rainer

    2006-08-01

    The term space weather refers to conditions on the Sun and in the solar wind, magnetosphere, ionosphere, and thermosphere that can influence the performance and reliability of space-borne and ground-based technological systems and that can affect human life and health. Our modern hi-tech society has become increasingly vulnerable to disturbances from outside the Earth system, in particular to those initiated by explosive events on the Sun: Flares release flashes of radiation that can heat up the terrestrial atmosphere such that satellites are slowed down and drop into lower orbits, solar energetic particles accelerated to near-relativistic energies may endanger astronauts traveling through interplanetary space, and coronal mass ejections are gigantic clouds of ionized gas ejected into interplanetary space that after a few hours or days may hit the Earth and cause geomagnetic storms. In this review, I describe the several chains of actions originating in our parent star, the Sun, that affect Earth, with particular attention to the solar phenomena and the subsequent effects in interplanetary space.

  11. The Internal Subbetic of the Velez Rubio area (SE Spain): Is it tectonically detached or not?

    NASA Astrophysics Data System (ADS)

    Sanz de Galdeano, Carlos; López Garrido, Angel Carlos; Andreo, Bartolomé

    2015-01-01

    The sierras of Maria and Maimon form part of the Internal Subbetic in the eastern part of the Betic Cordillera, in contact with the Internal Zone. Previous papers have interpreted the Internal Subbetic as being tectonically detached at its bottom, thrusting the Solana Fm., and moreover thrusting the Internal Zone. Nevertheless, the analysis of the structure of these sierras (with great development of folds), and that of the Sierra del Gigante, indicates that this detachment does not exist and, on the contrary, the structure is clearly rooted. Moreover, the general rectilinear trend of the contact between the Internal and External Zones leads to the interpretation that it in fact corresponds to a dextral transcurrent contact, this contention being supported by the analysis of minor faults. According to the age of the younger sediments involved (the Espejos and Solana Fms.), the main deformation processes occurred from the early Miocene and continued during the middle Miocene, at least in part. The structure and characteristics of the geologic evolution of this area are comparable to that of the Internal Subbetic (Penibetic) in the western part of the cordillera.

  12. A rapid hydrolysis method and DABS-Cl derivatization for complete amino acid analysis of octreotide acetate by reversed phase HPLC.

    PubMed

    Akhlaghi, Yousef; Ghaffari, Solmaz; Attar, Hossein; Alamir Hoor, Amir

    2015-11-01

    Octreotide as a synthetic cyclic octapeptide is a somatostatin analog with longer half-life and more selectivity for inhibition of the growth hormone. The acetate salt of octreotide is currently used for medical treatment of somatostatin-related disorders such as endocrine and carcinoid tumors, acromegaly, and gigantism. Octreotide contains both cysteine and tryptophan residues which make the hydrolysis part of its amino acid analysis procedure very challenging. The current paper introduces a fast and additive-free method which preserves tryptophan and cysteine residues during the hydrolysis. Using only 6 M HCl, this hydrolysis process is completed in 30 min at 150 °C. This fast hydrolysis method followed by pre-column derivatization of the released amino acids with 4-N,N-dimethylaminoazobenzene-4'-sulfonyl chloride (DABS-Cl) which takes only 20 min, makes it possible to do the complete amino acid analysis of an octreotide sample in a few hours. The highly stable-colored DABS-Cl derivatives can be detected in 436 nm in a reversed phase chromatographic system, which eliminates spectral interferences to a great extent. The amino acid analysis of octreotide acetate including hydrolysis, derivatization, and reversed phase HPLC determination was validated according to International Conference of Harmonization (ICH) guidelines. PMID:26002809

  13. Prefoldin and Pins synergistically regulate asymmetric division and suppress dedifferentiation

    PubMed Central

    Zhang, Yingjie; Rai, Madhulika; Wang, Cheng; Gonzalez, Cayetano; Wang, Hongyan

    2016-01-01

    Prefoldin is a molecular chaperone complex that regulates tubulin function in mitosis. Here, we show that Prefoldin depletion results in disruption of neuroblast polarity, leading to neuroblast overgrowth in Drosophila larval brains. Interestingly, co-depletion of Prefoldin and Partner of Inscuteable (Pins) leads to the formation of gigantic brains with severe neuroblast overgrowth, despite that Pins depletion alone results in smaller brains with partially disrupted neuroblast polarity. We show that Prefoldin acts synergistically with Pins to regulate asymmetric division of both neuroblasts and Intermediate Neural Progenitors (INPs). Surprisingly, co-depletion of Prefoldin and Pins also induces dedifferentiation of INPs back into neuroblasts, while depletion either Prefoldin or Pins alone is insufficient to do so. Furthermore, knocking down either α-tubulin or β-tubulin in pins- mutant background results in INP dedifferentiation back into neuroblasts, leading to the formation of ectopic neuroblasts. Overexpression of α-tubulin suppresses neuroblast overgrowth observed in prefoldin pins double mutant brains. Our data elucidate an unexpected function of Prefoldin and Pins in synergistically suppressing dedifferentiation of INPs back into neural stem cells. PMID:27025979

  14. Chryse Basin channels: low-gradients and ponded flows.

    USGS Publications Warehouse

    Lucchitta, B.K.; Ferguson, H.M.

    1983-01-01

    Gradients on the floors of the Martian outflow channels that are derived from radar-elevation profiles across Lunae Planum and Chryse Basin have much lower values than those obtained from the U.S. Geological Survey's topographic map. Whereas the gradients of Maja and Ares Valles are similar to those of the catastrophic flood channels in the Scablands of Washington State, the gradients of Simud and Tiu Valles are essentially level, and the movement of fluids to the N poses problems. It is proposed that ponding may have formed lakes in depressions associated with the Valles Marineris grabens, ancient craters in the chaotic terrain area, and possibly even the regional low where most chaotic terrains occur. It is envisaged that lakes eventually overflowed, forming the present channels. When dams broke, floods were released catastrophically, with a final gigantic flood from the Valles Marineris system of troughs, which would have had sufficient head to move fluids across nearly level gradients through the Simud and Tiu channels. -P.Br.

  15. Megafloods and Clovis cache at Wenatchee, Washington

    NASA Astrophysics Data System (ADS)

    Waitt, Richard B.

    2016-05-01

    Immense late Wisconsin floods from glacial Lake Missoula drowned the Wenatchee reach of Washington's Columbia valley by different routes. The earliest debacles, nearly 19,000 cal yr BP, raged 335 m deep down the Columbia and built high Pangborn bar at Wenatchee. As advancing ice blocked the northwest of Columbia valley, several giant floods descended Moses Coulee and backflooded up the Columbia past Wenatchee. Ice then blocked Moses Coulee, and Grand Coulee to Quincy basin became the westmost floodway. From Quincy basin many Missoula floods backflowed 50 km upvalley to Wenatchee 18,000 to 15,500 years ago. Receding ice dammed glacial Lake Columbia centuries more-till it burst about 15,000 years ago. After Glacier Peak ashfall about 13,600 years ago, smaller great flood(s) swept down the Columbia from glacial Lake Kootenay in British Columbia. The East Wenatchee cache of huge fluted Clovis points had been laid atop Pangborn bar after the Glacier Peak ashfall, then buried by loess. Clovis people came five and a half millennia after the early gigantic Missoula floods, two and a half millennia after the last small Missoula flood, and two millennia after the glacial Lake Columbia flood. People likely saw outburst flood(s) from glacial Lake Kootenay.

  16. A New Azhdarchid Pterosaur from the Late Cretaceous of the Transylvanian Basin, Romania: Implications for Azhdarchid Diversity and Distribution

    PubMed Central

    Vremir, Mátyás; Kellner, Alexander W. A.; Naish, Darren; Dyke, Gareth J.

    2013-01-01

    We describe a new taxon of medium-sized (wing span ca. 3 m) azhdarchid pterosaur from the Upper Cretaceous Transylvanian Basin (Sebeş Formation) of Romania. This specimen is the most complete European azhdarchid yet reported, comprising a partially articulated series of vertebrae and associated forelimb bones. The new taxon is most similar to the Central Asian Azhdarcho lancicollis Nessov but possesses a suite of autapomorphies in its vertebrae that include the relative proportions of cervicals three and four and the presence of elongated prezygapophyseal pedicles. The new taxon is interesting in that it lived contemporaneously with gigantic forms, comparable in size to the famous Romanian Hatzegopteryx thambema. The presence of two distinct azhdarchid size classes in a continental depositional environment further strengthens suggestions that these pterosaurs were strongly linked to terrestrial floodplain and wooded environments. To support this discussion, we outline the geological context and taphonomy of our new specimen and place it in context with other known records for this widespread and important Late Cretaceous pterosaurian lineage. PMID:23382886

  17. Sliding-surface-liquefaction of sand-dry ice mixture and submarine landslides

    NASA Astrophysics Data System (ADS)

    Fukuoka, H.; Tsukui, A.

    2010-12-01

    In the historic records of off-shore mega-earthquakes along the subduction zone offshore Japan, there are a lot of witnesses about large-scale burning of flammable gas possibly ejected from sea floor. This gas was supposed to be the dissolved methane hydrates (MH), which have been found in the soundings of IODP and other oceanology projects. Since the vast distribution of the BSR in the continental margins, a lot of papers have been published which pointed out the possibilities of that gasification of those hydrates could have triggered gigantic submarine landslides. Global warming or large earthquake or magma intrusion may trigger extremely deep gigantic landslides in continental margins that which could cause catastrophic tsunami. However, recent triaxial compression tests on artificially prepared sand-MH-mixture samples revealed that the they have slightly higher strength than the ones of only sands and MH’s endothermal characteristics may resist against accelerating shear and large-displacement landslides as well. While, the stress-controlled undrained ring shear apparatuses have been developed by Sassa and Fukuoka at Disaster Prevention Research Institute, Kyoto University to reproduce subaerial landslides induced by earthquakes and rainfalls. Using the apparatuses, they found localized liquefaction phenomenon along the deep saturated potential sliding surface due to excess pore pressure generation during the grain crushing induced bulk volume change. This phenomenon was named as “sliding surface liquefaction.” Similar sudden large pore pressure generation was observed in pore pressure control test simulating rain-induced landslides. In this paper, authors examined the shear behavior of the dry sand-dry ice mixture under constant normal stress and shear speed control tests using the latest ring shear apparatus. Sample was mixture of silica sands and dry-ice pellets (frozen carbon-dioxide). Those mixtures are often used for studying the mechanism of the

  18. HUBBLE VIEWS A STARRY RING WORLD BORN IN A HEAD-ON COLLISION

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [Right] - A rare and spectacular head-on collision between two galaxies appears in this NASA Hubble Space Telescope true-color image of the Cartwheel Galaxy, located 500 million light-years away in the constellation Sculptor. The new details of star birth resolved by Hubble provide an opportunity to study how extremely massive stars are born in large fragmented gas clouds. The striking ring-like feature is a direct result of a smaller intruder galaxy -- possibly one of two objects to the right of the ring -- that careened through the core of the host galaxy. Like a rock tossed into a lake, the collision sent a ripple of energy into space, plowing gas and dust in front of it. Expanding at 200,000 miles per hour, this cosmic tsunami leaves in its wake a firestorm of new star creation. Hubble resolves bright blue knots that are gigantic clusters of newborn stars and immense loops and bubbles blown into space by exploding stars (supernovae) going off like a string of firecrackers. The Cartwheel Galaxy presumably was a normal spiral galaxy like our Milky Way before the collision. This spiral structure is beginning to re-emerge, as seen in the faint arms or spokes between the outer ring and bulls-eye shaped nucleus. The ring contains at least several billion new stars that would not normally have been created in such a short time span and is so large (150,000 light-years across) our entire Milky Way Galaxy would fit inside. Hubble's new view does not solve the mystery as to which of the two small galaxies might have been the intruder. The blue galaxy is disrupted and has new star formation which strongly suggests it is the interloper. However, the smoother-looking companion has no gas, which is consistent with the idea that gas was stripped out of it during passage through the Cartwheel Galaxy. [Top Left] - Hubble's detailed view shows the knot-like structure of the ring, produced by large clusters of new star formation. Hubble also resolves the effects of thousands of

  19. The potential for crustal resources on Mars

    NASA Technical Reports Server (NTRS)

    Cordell, Bruce M.; Gillett, Stephen L.

    1991-01-01

    Martian resources pose not only an interesting scientific challenge but also have immense astronautical significance because of their ability to enhance mission efficiency, lower launch and program costs, and stimulate the development of large Mars surface facilities. Although much terrestrial mineralization is associated with plate tectonics and Mars apparently possesses a thick, stationary lithosphere, the presence of crustal swells, rifting, volcanism, and abundant volatiles indicates that a number of sedimentary, hydrothermal, dry-magma mineral concentration processes may have operated on Mars. For example, in Colorado Plateau-style (roll-front) deposits, uranium precipitation is localized by redox variations in groundwater. Also, evaporites (either in salt pans or even interstitially in pore spaces) might concentrate Cl, Li, and K. Many Martian impact craters have been modified by volcanism and probably have been affected by rising magma bodies interacting with ground ice or water. Such conditions might produce hydrothermal circulations and element concentrations. If the high sulfur content found by the Viking landers typifies Martian abundances, sulfide ore bodies may have been formed locally. Mineral-rich Africa seems to share many volcanic and tectonic characteristics with portions of Mars and may suggest Mars' potential mineral wealth. For example, the rifts of Valles Marineris are similar to the rifts in east Africa, and may both result from a large mantle plume rising from the interior and disrupting the surface. The gigantic Bushveld complex of South Africa, an ancient layered igneous intrusion that contains ores of chromium and Pt-group metals, illustrates the sort of dry-magma processes that also could have formed local element concentrations on Mars, especially early in the planet's history when heat flow was higher.

  20. Traditional and novel aspects of the metabolic actions of growth hormone.

    PubMed

    Sperling, Mark A

    2016-06-01

    Growth hormone has been known to be diabetogenic for almost a century and it's diabetogenic properties fostered consideration of excessive and abnormal GH secretion as a cause of diabetes, as well as a role in the microvascular complications, especially retinopathy. However, besides inducing insulin resistance, GH also is lipolytic and a major anabolic hormone for nitrogen retention and protein synthesis. These actions are best illustrated at the extremes of GH secretion: Gigantism/acromegaly is characterized by excessive growth, CHO intolerance, hyperplasia of bone, little body fat and prominent muscle development, whereas total deficiency of GH secretion or action is associated with adiposity, poor growth, and poor muscle development. These actions also become apparent during puberty and pregnancy, times when GH secretion is increased and account for the characteristic changes in body composition and tendency to diabetes. More recently, tissue specific deletions of the GH receptor (GHR), have uncovered newer metabolic effects including it's essential role in triglyceride export from the liver when GHR is deleted in the liver, leading to hepatic steatosis and ultimately to hepatic adenoma formation, effects which may explain these findings in obesity, a state of diminished GH secretion and action. In addition deletion of GH action in muscle and fat is associated with specific patterns of disturbed phenotype and metabolic effects in CHO, fat, and protein metabolism affecting the specific tissue and whole body function. This chapter provides an overview of these classic and newer metabolic functions of GH, placing this hormone and its actions in a central role of body fuel economy in health and disease. PMID:26194064

  1. The vast thin plane of M31 corotating dwarfs: an additional fossil signature of the M31 merger and of its considerable impact in the whole Local Group

    NASA Astrophysics Data System (ADS)

    Hammer, François; Yang, Yanbin; Fouquet, Sylvain; Pawlowski, Marcel S.; Kroupa, Pavel; Puech, Mathieu; Flores, Hector; Wang, Jianling

    2013-06-01

    The recent discovery by Ibata et al. of a vast thin disc of satellites (VTDS) around M31 offers a new challenge for the understanding of the Local Group properties. This comes in addition to the unexpected proximity of the Magellanic Clouds (MCs) to the Milky Way (MW), and to another vast polar structure (VPOS), which is almost perpendicular to our Galaxy disc. We find that the VTDS plane is coinciding with several stellar, tidally induced streams in the outskirts of M31, and, that its velocity distribution is consistent with that of the giant stream (GS). This is suggestive of a common physical mechanism, likely linked to merger tidal interactions, knowing that a similar argument may apply to the VPOS at the MW location. Furthermore, the VTDS is pointing towards the MW, being almost perpendicular to the MW disc, as the VPOS is. We compare these properties to the modelling of M31 as an ancient, gas-rich major merger, which has been successfully used to predict the M31 substructures and the GS origin. We find that without fine tuning, the induced tidal tails are lying in the VTDS plane, providing a single and common origin for many stellar streams and for the vast stellar structures surrounding both the MW and M31. The model also reproduces quite accurately positions and velocities of the VTDS spheroidal dwarfs. Our conjecture leads to a novel interpretation of the Local Group past history, as a gigantic tidal tail due to the M31 ancient merger is expected to send material towards the MW, including the MCs. Such a link between M31 and the MW is expected to be quite exceptional, though it may be in qualitative agreement with the reported rareness of MW-MCs systems in nearby galaxies.

  2. Morphological variation of henequen (Agave fourcroydes, Agavaceae) germplasm and its wild ancestor (A. angustifolia) under uniform growth conditions: diversity and domestication.

    PubMed

    Colunga-Garciamarin, P; May-Pat, F

    1997-11-01

    Extant variants of henequen (Agave fourcroydes Lem.) and wild populations of its putative ancestor A. angustifolia Haw. were grown in the Mexican state of Yucatan for 10 yr under homogeneous conditions. A statistical and numerical analysis of their patterns of morphological variation was performed as part of broader research to provide evidence of its genetic diversity, evolutionary relationships and changes under human selection. A comparison with results of a similar analysis under natural growing conditions was also made. The study indicated the following. (1) Under natural growth conditions, the three putative wild ecotypes are morphologically distinct, but under uniform conditions only populations growing in Tropical subdeciduous forest may be distinguished from the other two, thus indicating the probable existence of only two ecotypes: one growing in Coastal dunes and Tropical subdeciduous forest, and the other growing in Tropical deciduous forest. (2) This last ecotype is the most similar to cultivated variants. Within its populations, the most similar to the cultivated is that known as Chelem White, gathered by artisans for its textile use. (3) The cordage-cultivated Sac Ki and Yaax Ki differ from wild populations in four syndromes of domestication: gigantism, greater fibrosity, less thorniness, and less reproductive capacity. The lower cv of their characteristics compared with those of wild populations suggest less genetic diversity. (4) Kitam Ki is probably a textile-cultivated variant of recent introduction and/or a variant in which the artificial selection process has had different direction and intensity. (5) Improved growth conditions in the botanic garden resulted in a decreased cv, an increase in size and fiber content, and a reduction of thorniness for both wild and cultivated variants. Given that wild populations with desirable characteristics exist and that these characteristics are highly plastic and respond positively to cultivation, then

  3. West-Antarctic Ice Streams: Analog to Ice Flow in Channels on Mars

    NASA Technical Reports Server (NTRS)

    Lucchitta, B. K.

    1997-01-01

    Sounding of the sea floor in front of the Ross Ice Shelf in Antarctica recently revealed large persistent patterns of longitudinal megaflutes and drumlinoid forms, which are interpreted to have formed at the base of ice streams during the list glacial advance. The flutes bear remarkable resemblance to longitudinal grooves and highly elongated streamlined islands found on the floors of some large martian channels, called outflow channels. ln addition, other similarities exist between Antarctic ice streams and outflow channels. Ice streams are 30 to 80 km wide and hundreds of kilometers long, as are the martian channels. Ice stream beds are below sea level. Floors of many martian outflow channels lie below martian datum, which may have been close to or below past martian sea levels. The Antarctic ice stream bed gradient is flat and locally may go uphill, and surface slopes are exceptionally low. So are gradients of martian channels. The depth to the bed in ice streams is 1 to 1.5 km. At bankful stage, the depth of the fluid in outflow channels would have been 1 to 2 km. These similarities suggest that the martian outflow channels, whose origin is commonly attributed to gigantic catastrophic floods, were locally filled by ice that left a conspicuous morphologic imprint. Unlike the West-Antarctic-ice streams, which discharge ice from an ice sheet, ice in the martian channels came from water erupting from the ground. In the cold martian environment, this water, if of moderate volume, would eventually freeze. Thus it may have formed icings on springs, ice dams and jams on constrictions in the channel path, or frozen pools. Given sufficient thickness and downhill surface gradient, these ice masses would have moved; and given the right conditions, they could have moved like Antarctic ice streams.

  4. Magnetic Signatures of Impact Fractured Rocks from Sierra Madera, Texas, USA - Implications to Magnetic Anomalies on Mars

    NASA Astrophysics Data System (ADS)

    Adachi, T.; Kletetschka, G.; Wasilewski, P. J.; Mikula, V.

    2007-05-01

    Mars Express Orbiter (sounding radar data) revealed that craters of ancient origin had been covered by thick sediments in northern hemisphere. Mars MOLA topography mission identified many crater on Mars surface. Thus despite the Mars dichotomy, both northern and southern hemisphere have been covered by impacts to similar density. Mars currently has no global magnetic field of internal origin. In southern hemisphere, magnetic field intensities due to anomalies of remanent origin are much lower over the gigantic impact craters (e.g. Hellas, Prometheus, and Argyre). Low magnetic field may not relate to the absence of internal dynamo but due to impacts. For example, the aerial survey over a two billion year old, largest crater on Earth, Vredefort in South Africa observed much lower magnetic intensity over the crater, despite of the strongly magnetized simgle domain (SD) magnetite in shocked granites. Randomized magnetic vector orientations caused by impact may be the origin of the lower magnetic field observed on both Vredefort and Mars. We conducted magnetic analysis for a suite of Sierra Madera Impact deformed rock sites with complete shatter cone structures and multiple striated joint set (MSJS), and the initial results were intriguing. NRM vector orientations, REM ratios, and AF demagnetization curves showed contrasted magnetic signatures between the sites as well as within the samples. The NRM signatures in small scale shatter cones and larger scale shatter cones indicated shock demagnetization (SDM). The peculiar signatures of the site with MSJS may be both SDM and shock magnetization (SRM). We characterized the complexity and distinct magnetic signatures of impact fractured rocks. The results suggest that the size of the shatter cones and structures may reflect the magnetic signatures of both intensity and directions. Also, the dimensional scale of shatter cones is indicative parameters for randomization of the magnetic vector orientations. Such variations may

  5. Billions of basepairs of recently expanded, repetitive sequences are eliminated from the somatic genome during copepod development

    PubMed Central

    2014-01-01

    Background Chromatin diminution is the programmed deletion of DNA from presomatic cell or nuclear lineages during development, producing single organisms that contain two different nuclear genomes. Phylogenetically diverse taxa undergo chromatin diminution — some ciliates, nematodes, copepods, and vertebrates. In cyclopoid copepods, chromatin diminution occurs in taxa with massively expanded germline genomes; depending on species, germline genome sizes range from 15 – 75 Gb, 12–74 Gb of which are lost from pre-somatic cell lineages at germline – soma differentiation. This is more than an order of magnitude more sequence than is lost from other taxa. To date, the sequences excised from copepods have not been analyzed using large-scale genomic datasets, and the processes underlying germline genomic gigantism in this clade, as well as the functional significance of chromatin diminution, have remained unknown. Results Here, we used high-throughput genomic sequencing and qPCR to characterize the germline and somatic genomes of Mesocyclops edax, a freshwater cyclopoid copepod with a germline genome of ~15 Gb and a somatic genome of ~3 Gb. We show that most of the excised DNA consists of repetitive sequences that are either 1) verifiable transposable elements (TEs), or 2) non-simple repeats of likely TE origin. Repeat elements in both genomes are skewed towards younger (i.e. less divergent) elements. Excised DNA is a non-random sample of the germline repeat element landscape; younger elements, and high frequency DNA transposons and LINEs, are disproportionately eliminated from the somatic genome. Conclusions Our results suggest that germline genome expansion in M. edax reflects explosive repeat element proliferation, and that billions of base pairs of such repeats are deleted from the somatic genome every generation. Thus, we hypothesize that chromatin diminution is a mechanism that controls repeat element load, and that this load can evolve to be divergent

  6. Benthic associations in bathyal and hadal depths off the Pacific coast of north eastern Japan: physiognomies and site factors

    NASA Astrophysics Data System (ADS)

    Horikoshi, Masuoki; Fujita, Toshihiko; Ohta, Suguru

    Off north-eastern Japan, the continental slope is rather narrow. It slopes steeply down to a depth of 1000m, but then forms a flat terrace between 1000 and 3000 m. Beyond 3000m the slope drops steeply down to the axis of the Japan Trench (7500m). Only one community type occurs in the upper bathyal zone (200-600m), an Ophiura association whose physiognomy is a “turf” of ophiuroids. The middle bathyal zone (600-1200m) is occupied by two types of community. The predominant community is an association characterized by an asteroid, Ceramaster, and a demersal fish, Sebastolobus, which has no characteristic physiognomy. The second is a comatulid community, which occurs on the shoulder of the slope as a comatulid “park”. The lower bathyal zones (1200-3000m) is inhabited by two distinct associations one of which has two facies. Most of the terrace area is occupied by an amphiurid association. In the plateau-like areas where there is a higher flow regime, there are sporadic, or sometimes rather dense stands of a coelenterate - the Radicipes facies. Whereas at the deeper site current are slower and the sediment is muddy, a Megayoldia - Ascorhynchus facies occurs in which a bivalve and a gigantic pycnogonid are found associated with amphiurids. The other community-type is a tubicolous-polychaete association which consists of a dominant polychaete species with a rather thin sandy tube which is associated always with a caprellid. This association is found on a shoulder-like topography, where bottom currents are expected to be constant and sediment is sandy. In the axis of the Japan Trench, where the sediment is soft mud, a small globular bivalve, Kelliella, is numerically dominant, which is associated with a holothurian, Elpidia, and a demersal fish, Careproctus. Nearby where the topography is a gentle slope, the community is typified by a dominant isopod, Storthyngura sp., accompanied by a bivalve, Spinula, and an actiniarian, Galatheanthemum.

  7. [Gender in view].

    PubMed

    1998-03-01

    A manual recently published by Mexico¿s National System for Integral Development of the Family, ¿The gender perspective: a tool for constructing equity between men and women¿, is intended to put into practice the Cairo accords. The gender perspective has been applied in recent years to interpretation of the situation of women in past and present societies. Gender is not sex; it is the manner in which societies have symbolized and understood relations between men and women. The manual concludes that the main difference between the sexes beyond the obvious genital differences is in the greater musculature and strength of males. In contemporary societies, these attributes are less needed than technical knowledge and skills, which may be obtained by either sex. Economic evolution has led increasing numbers of women to work outside their homes. The gender roles assigned for millennia, and accepted as the natural order, are no longer adequate. The power of men has been preserved by attributing the gigantic cultural differences resulting from specialization into male and female roles to the small physical differences between the sexes. Governments have slowly established legal equity, but discrimination against women has not disappeared in the workplace, public offices, or any other social sphere, and their incorporation into the work force has left them with the double workday as they continue to perform the great bulk of domestic work. It is therefore necessary to seek equity as well as equality, understood as the creation of equivalent opportunities for men and women. PMID:12349308

  8. Change in and long-term investigation of neuro-otologic disorders in disaster-stricken Fukushima prefecture: retrospective cohort study before and after the Great East Japan Earthquake.

    PubMed

    Hasegawa, Jun; Hidaka, Hiroshi; Kuriyama, Shinichi; Obara, Taku; Hashimoto, Ken; Tateda, Yutaka; Okumura, Yuri; Kobayashi, Toshimitsu; Katori, Yukio

    2015-01-01

    On March 11, 2011, Japan's northeast Pacific coast was hit by a gigantic earthquake and subsequent tsunami. Soma City in Fukushima Prefecture is situated approximately 44 km north of Fukushima Daiichi Nuclear Power Plant. Soma General Hospital is the only hospital in Soma City that provides full-time otolaryngological medical care. We investigated the changes in new patients from one year before to three years after the disaster. We investigated 18,167 new patients treated at our department during the four years from April 1, 2010 to March 31, 2014. Of the new patients, we categorized the diagnoses into Meniere's disease, acute low-tone sensorineural hearing loss, vertigo, sudden deafness, tinnitus, and facial palsy as neuro-otologic symptoms. We also investigated the changes in the numbers of patients whom we examined at that time concerning other otolaryngological disorders, including epistaxis, infectious diseases of the laryngopharynx, and allergic rhinitis. The total number of new patients did not change remarkably on a year-to-year basis. Conversely, cases of vertigo, Meniere's disease, and acute low-tone sensorineural hearing loss increased in number immediately after the disaster, reaching a plateau in the second year and slightly decreasing in the third year. Specifically, 4.8% of patients suffering from these neuro-otologic diseases had complications from depression and other mental diseases. With regard to new patients in our department, there was no apparent increase in the number of patients suffering from diseases other than neuro-otologic diseases, including epistaxis, and allergic rhinitis. Patients suffering from vertigo and/or dizziness increased during the first few years after the disaster. These results are attributed to the continuing stress and tension of the inhabitants. This investigation of those living in the disaster area highlights the need for long-term support. PMID:25849607

  9. Testing for intraspecific postzygotic isolation between cryptic lineages of Pseudacris crucifer

    PubMed Central

    Stewart, Kathryn A; Lougheed, Stephen C

    2013-01-01

    Phenotypically cryptic lineages appear common in nature, yet little is known about the mechanisms that initiate and/or maintain barriers to gene flow, or how secondary contact between them might influence evolutionary trajectories. The consequences of such contact between diverging lineages depend on hybrid fitness, highlighting the potential for postzygotic isolating barriers to play a role in the origins of biological species. Previous research shows that two cryptic, deeply diverged intraspecific mitochondrial lineages of a North American chorus frog, the spring peeper (Pseudacris crucifer), meet in secondary contact in Southwestern Ontario, Canada. Our study quantified hatching success, tadpole survival, size at metamorphosis, and development time for experimentally generated pure lineage and hybrid tadpoles. Results suggest that lineages differ in tadpole survival and that F1 hybrids may have equal fitness and higher than average mass at metamorphosis compared with pure parental crosses. These findings imply hybrid early life viability may not be the pivotal reproductive isolation barrier helping to maintain lineage boundaries. However, we observed instances of tadpole gigantism, failure to metamorphose, and bent tails in some tadpoles from hybrid families. We also speculate and provide some evidence that apparent advantages or similarities of hybrids compared with pure lineage tadpoles may disappear when tadpoles are raised with competitors of different genetic makeup. This pilot study implies that ecological context and consideration of extrinsic factors may be a key to revealing mechanisms causing negative hybrid fitness during early life stages, a provocative avenue for future investigations on barriers to gene flow among these intraspecific lineages. PMID:24363891

  10. Assessment of regional influence from a petrochemical complex by modeling and fingerprint analysis of volatile organic compounds (VOCs)

    NASA Astrophysics Data System (ADS)

    Su, Yuan-Chang; Chen, Sheng-Po; Tong, Yu-Huei; Fan, Chen-Lun; Chen, Wei-Hao; Wang, Jia-Lin; Chang, Julius S.

    2016-09-01

    This study aimed to demonstrate a strategy to investigate the influence of volatile organic compounds (VOCs) on its neighboring districts from a gigantic petrochemical complex. Monitoring of the VOCs in the region was achieved by a nine-station network, dubbed photochemical assessment measurement stations (PAMS), which produced speciated mixing ratios of 54 non-methane hydrocarbons (NMHCs) to represent VOCs with an hourly resolution within a 20 km radius. One-year (2013/10/1-2014/9/30) worth of PAMS data from the network were used in forms of total NMHCs (called PAMS-TNMHC) and speciated mixing ratios. Three dimensional modeling coupled with PAMS measurements successfully elucidated how the study domain was affected by the petrochemical complex and distant sources under three typical seasonal wind patterns: northeast monsoonal, southwest monsoonal, and local-circulation. More exquisite analysis of influence on the neighboring districts was permitted with the use of speciated mixing ratios of VOCs provided by the PAMS network. The ratios of ethylene/acetylene (E/A) > 3 and propylene/acetylene (P/A) > 1.5 were used as indicators to reveal the PAMS sites affected by the petrochemical emissions. Consequently, the hourly speciated data from the nine PAMS sites enabled a finer assessment of the districts affected by the complex to calculate the percent time of influence (dubbed TI%) for all the sites (districts). It was found that the region was more affected by the complex under both the northeast monsoonal and the local-circulation wind types with some of the PAMS sites greater than 5% for the TI%. By contrast, influence on the region was found minimal under the southwest monsoonal flow with the TI% small than 1.5% across all sites. This study successfully devised a method of assessment with the use of speciated measurements of selected VOCs and modeling to assess the influence of a prominent source on the neighboring districts by filtering out irrelevant sources under

  11. Assessment of Equine Autoimmune Thrombocytopenia (EAT) by flow cytometry

    PubMed Central

    Nunez, Rafael; Gomes-Keller, M Alice; Schwarzwald, Colin; Feige, Karsten

    2001-01-01

    Rationale Thrombocytopenia is a platelet associated process that occurs in human and animals as result of i) decreased production; ii) increased utilization; iii) increased destruction coupled to the presence of antibodies, within a process know as immune-mediated thrombocytopenia (IMT); or iv) platelet sequestration. Thus, the differentiation of the origin of IMT and the development of reliable diagnostic approaches and methodologies are important in the clarification of IMT pathogenesis. Therefore, there is a growing need in the field for easy to perform assays for assessing platelet morphological characteristics paired with detection of platelet-bound IgG. Objectives This study is aimed to develop and characterize a single color flow cytometric assay for detection of platelet-bound IgG in horses, in combination with flow cytometric assessment of platelet morphological characteristics. Findings The FSC and SSC evaluation of the platelets obtained from the thrombocytopenic animals shows several distinctive features in comparison to the flow cytometric profile of platelets from healthy animals. The thrombocytopenic animals displayed i) increased number of platelets with high FSC and high SSC, ii) a significant number of those gigantic platelets had strong fluorescent signal (IgG bound), iii) very small platelets or platelet derived microparticles were found significantly enhanced in one of the thrombocytopenic horses, iv) significant numbers of these microplatelet/microparticles/platelet-fragments still carry very high fluorescence. Conclusions This study describes the development and characterization of an easy to perform, inexpensive, and noninvasive single color flow cytometric assay for detection of platelet-bound IgG, in combination with flow cytometric assessment of platelet morphological characteristics in horses. PMID:11313001

  12. Status of Solar Sail Propulsion Within NASA - Moving Toward Interstellar Travel

    NASA Technical Reports Server (NTRS)

    Johnson, Les

    2015-01-01

    NASA is developing solar sail propulsion for two near-term missions and laying the groundwork for their future use in deep space and interstellar precursor missions. Solar sails use sunlight to propel vehicles through space by reflecting solar photons from a large, mirror-like sail made of a lightweight, highly reflective material. This continuous photon pressure provides propellantless thrust, allowing for very high (Delta)V maneuvers on long-duration, deep space exploration. Since reflected light produces thrust, solar sails require no onboard propellant. The Near Earth Asteroid (NEA) Scout mission, managed by MSFC, will use the sail as primary propulsion allowing it to survey and image one or more NEA's of interest for possible future human exploration. Lunar Flashlight, managed by JPL, will search for and map volatiles in permanently shadowed Lunar craters using a solar sail as a gigantic mirror to steer sunlight into the shaded craters. The Lunar Flashlight spacecraft will also use the propulsive solar sail to maneuver into a lunar polar orbit. Both missions use a 6U cubesat architecture, a common an 85 sq m solar sail, and will weigh less than 12 kilograms. Both missions will be launched on the first flight of the Space Launch System in 2018. NEA Scout and Lunar Flashlight will serve as important milestones in the development of solar sail propulsion technology for future, more ambitious missions including the Interstellar Probe - a mission long desired by the space science community which would send a robotic probe beyond the edge of the solar system to a distance of 250 Astronomical Units or more. This paper will summarize the development status of NEA Scout and Lunar Flashlight and describe the next steps required to enable an interstellar solar sail capability.

  13. Single cell analysis demonstrating somatic mosaicism involving 11p in a patient with paternal isodisomy and Beckwith-Wiedemann Syndrome

    SciTech Connect

    Bischoff, F.Z.; McCaskill, C.; Subramanian, S.

    1994-09-01

    Beckwith-Wiedemann Syndrome (BWS) is characterized by numerous growth abnormalities including exomphalos, macroglossia, gigantism, and hemihypertrophy or hemihyperplasia. The {open_quotes}BWS gene{close_quotes} appears to be maternally repressed and is suspected to function as a growth factor or regulator of somatic growth, since activation of this gene through a variety of mechanisms appears to result in somatic overgrowth and tumor development. Mosaic paternal isodisomy of 11p has been observed previously by others in patients with BWS by Southern blot analysis of genomic DNA. The interpretation of these results was primarily based on the intensities of the hybridization signals for the different alleles. In our study, we demonstrate somatic mosaicism directly through PCR and single cell analysis. Peripheral blood was obtained from a patient with BWS and initial genomic DNA analysis by PCR was suggestive of somatic mosaicism for paternal isodisomy of 11p. Through micromanipulation, single cells were isolated and subjected to primer extention preamplification. Locus-specific microsatellite marker analyses by PCR were performed to determine the chromosome 11 origins in the preamplified individual cells. Two populations of cells were detected, a population of cells with normal biparental inheritance and a population of cells with paternal isodisomy of 11p and biparental disomy of 11q. Using the powerful approach of single cell analysis, the detected somatic mosaicism provides evidence for a mitotic recombinational event that has resulted in loss of the maternal 11p region and gain of a second copy of paternal 11p in some cells. The direct demonstration of mosaicism may explain the variable phenotypes and hemihypertrophy often observed in BWS.

  14. Building Baluchitherium and Indricotherium: imperial and international networks in early-twentieth century paleontology.

    PubMed

    Manias, Chris

    2015-01-01

    Over the first decades of the twentieth century, the fragmentary remains of a huge prehistoric ungulate were unearthed in scientific expeditions in India, Turkestan and Mongolia. Following channels of formal and informal empire, these were transported to collections in Britain, Russia and the United States. While striking and of immense size, the bones proved extremely difficult to interpret. Alternately naming the creature Paraceratherium, Baluchitherium and Indricotherium, paleontologists Clive Forster-Cooper, Alexei Borissiak and Henry Fairfield Osborn struggled over the reconstruction of this gigantic fossil mammal. However, despite these problems, shared work on the creature served as a focus for collaboration and exchange rather than rivalry between these three scientific communities. Not only did the initial interpretation and analysis depend on pre-existing connections between British and American paleontological institutions, but the need for comparative material, recognition and contacts brought British and American scholars into communication and exchange with their counterparts in the Soviet Union. This article examines these processes. It first uses these excavations as a comparative case-study of different manifestations of colonial science in this period, examining how scholars in the Britain, the Russian Empire and the United States used formal and informal colonial links to Asia to pursue new research. It then moves to examine how the common problem of reconstructing this giant animal drew metropolitan scientific communities together, at least for a time. The construction of the Baluchitherium and Indricotherium illustrates the drives to expand research both imperially and internationally in the early-twentieth century, but also the continual problems in resources, institutionalization, transport and communication that could run up against scientific work. PMID:25537636

  15. Diluted magnetic semiconductor superlattices and heterostructures

    NASA Astrophysics Data System (ADS)

    Datta, S.; Furdyna, J. K.; Gunshor, R. L.

    Diluted magnetic semiconductors (DMS) are mixed semiconducting crystals whose lattice is made up in part of substitutional magnetic ions. Cd 1-xMn xTe and Hg 1-xMn xTe are examples of such materials. Their structural and band parameters can be "tuned" by composition over a wide range. They can thus be exploited in situations completely similar to those involving Ga 1-xAl xAs. Using molecular beam epitaxy, we have grown Cd 1-xMn xTe superlattices with alternating Mn content, having up to 150 layers, with layer thickness ranging from 50 to 100 Å. The superlattice structure is clearly revealed by transmission electron microscopy and by zone-folding of the phonon spectrum observed in Raman scattering. Photoluminescence observed on Cd 1-xMn xTe superlattices is several orders of magnitude greater than that from a Cd 1-xMn xTe film with uniform Mn content, or from bulk Cd 1-xMn xTe specimens. The presence of localized magnetic moments in DMS results in a strong exchange interaction between these moments and band electrons. This in turn leads to gigantic Zeeman splittings of impurity states, exciton levels, Landau levels, and the bands themselves. Zeeman splittings as large as 20 meV (which in non-magnetic semiconductors would require unrealistic megagauss fields) are easily achieved in DMS in fields of several kilogauss. Since the magnitude of this exchange-induced splitting in DMS can be comparable to the binding energies and to the minigaps encountered in multiple quantum wells, DMS superlattices hold promise of a host of novel effects of both fundamental and applied interest.

  16. GPR101 Mutations are not a Frequent Cause of Congenital Isolated Growth Hormone Deficiency.

    PubMed

    Castinetti, F; Daly, A F; Stratakis, C A; Caberg, J-H; Castermans, E; Trivellin, G; Rostomyan, L; Saveanu, A; Jullien, N; Reynaud, R; Barlier, A; Bours, V; Brue, T; Beckers, A

    2016-06-01

    Patients with Xq26.3 microduplication present with X-linked acrogigantism (X-LAG) syndrome, an early-childhood form of gigantism due to marked growth hormone (GH) hypersecretion from mixed GH-PRL adenomas and hyperplasia. The microduplication includes GPR101, which is upregulated in patients' tumor tissue. The GPR101 gene codes for an orphan G protein coupled receptor that is normally highly expressed in the hypothalamus. Our aim was to determine whether GPR101 loss of function mutations or deletions could be involved in patients with congenital isolated GH deficiency (GHD). Taking advantage of the cohort of patients from the GENHYPOPIT network, we studied 41 patients with unexplained isolated GHD. All patients had Sanger sequencing of the GPR101 gene and array comparative genome hybridization (aCGH) to look for deletions. Functional studies (cell culture with GH secretion measurements, cAMP response) were performed. One novel GPR101 variant, c.589 G>T (p.V197L), was seen in the heterozygous state in a patient with isolated GHD. In silico analysis suggested that this variant could be deleterious. Functional studies did not show any significant difference in comparison with wild type for GH secretion and cAMP response. No truncating, frameshift, or small insertion-deletion (indel) GPR101 mutations were seen in the 41 patients. No deletion or other copy number variation at chromosome Xq26.3 was found on aCGH. We found a novel GPR101 variant of unknown significance, in a patient with isolated GH deficiency. Our study did not identify GPR101 abnormalities as a frequent cause of GH deficiency. PMID:26797872

  17. Lightning Interaction with the Lower Ionosphere: Effects of Mesospheric Ions and Geomagnetic Field

    NASA Astrophysics Data System (ADS)

    Marshall, R. A.; Inan, U. S.

    2011-12-01

    The interaction between the lightning electromagnetic pulse (EMP) and quasi-electrostatic (QE) fields and the D-region ionosphere has been observed optically in the past 20 years through sprites, elves, and gigantic jets. Very-low-frequency (VLF) measurements have been used to measure direct ionospheric modification, which may comprise electron density changes and/or heating. In the same time period, a number of models have been used to study the lightning-ionosphere interaction. Here, we present new time-domain 2D and 3D models of the lightning-ionosphere interaction, including EMP and QE effects. These spherical-coordinate models include effects of Earth's magnetic field; effects of mesospheric and ionospheric electron and ion densities; and responses to arbitrary lightning amplitudes, waveforms, and orientations. In this paper, we use the new models to investigate the response of the ionosphere under varying conditions. First, we focus on the effects of different mesospheric ion density profiles. Mesospheric ions, for which measurements are nearly nonexistent, serve to reduce the amplitude of the electromagnetic pulse as it propagates towards the ionosphere; high ion densities will reduce the wave electric field enough that it does not exceed the breakdown field in the ionosphere. We demonstrate the relationship between the lightning parameters, ion density profile, and observed elve intensity, and show that elves are suppressed when the ion density is high. Second, we investigate the effects of the geomagnetic field magnitude and orientation on wave propagation in and through the ionosphere. We compare these simulation results with known global lightning distributions and compare to the observed whistler distributions onboard satellites.

  18. Evolution of High Tooth Replacement Rates in Sauropod Dinosaurs

    PubMed Central

    Smith, Kathlyn M.; Fisher, Daniel C.; Wilson, Jeffrey A.

    2013-01-01

    Background Tooth replacement rate can be calculated in extinct animals by counting incremental lines of deposition in tooth dentin. Calculating this rate in several taxa allows for the study of the evolution of tooth replacement rate. Sauropod dinosaurs, the largest terrestrial animals that ever evolved, exhibited a diversity of tooth sizes and shapes, but little is known about their tooth replacement rates. Methodology/Principal Findings We present tooth replacement rate, formation time, crown volume, total dentition volume, and enamel thickness for two coexisting but distantly related and morphologically disparate sauropod dinosaurs Camarasaurus and Diplodocus. Individual tooth formation time was determined by counting daily incremental lines in dentin. Tooth replacement rate is calculated as the difference between the number of days recorded in successive replacement teeth. Each tooth family in Camarasaurus has a maximum of three replacement teeth, whereas each Diplodocus tooth family has up to five. Tooth formation times are about 1.7 times longer in Camarasaurus than in Diplodocus (315 vs. 185 days). Average tooth replacement rate in Camarasaurus is about one tooth every 62 days versus about one tooth every 35 days in Diplodocus. Despite slower tooth replacement rates in Camarasaurus, the volumetric rate of Camarasaurus tooth replacement is 10 times faster than in Diplodocus because of its substantially greater tooth volumes. A novel method to estimate replacement rate was developed and applied to several other sauropodomorphs that we were not able to thin section. Conclusions/Significance Differences in tooth replacement rate among sauropodomorphs likely reflect disparate feeding strategies and/or food choices, which would have facilitated the coexistence of these gigantic herbivores in one ecosystem. Early neosauropods are characterized by high tooth replacement rates (despite their large tooth size), and derived titanosaurs and diplodocoids independently

  19. Rural telemedicine: satellites and fiber optics.

    PubMed

    Tyrer, H W; Wiedemeier, P D; Cattlet, R W

    2001-01-01

    Rural America Telemedicine requires very high bandwidth to provide timely transmission of large data sets. These resources may take decades to appear because of the economics of low population densities and costly installation, and the historically low rate of bandwidth improvement available from the common communication providers. Satellites provide the natural choice for communication between the rural primary care centers and the tertiary care hospital. Furthermore recent improvements in technologies have substantially reduced the costs of ground stations. A network of satellite ground stations with symmetric bandwidth connected by satellite is the architecture of choice. Analysis of multi-station satellite access clearly argues for distributed non-random methods and hence for appropriate handling of TCP data streams. However the overhead in delay of Satellite based TCP, as required for Internet access, substantially increases the transmission time and hence cost. Simulations of TCP/IP data over satellite links show a substantial reduction in transmission times. Initial business models show that the transmission cost per second is 60 times that of telephone lines while the increase in speed is nearly 3000 fold, effecting a 50 fold cost savings. But over decades, the infrastructure can be expected to improve. In particular speculative fiber optic installations in power lines and along major highways are betting on future traffic. These so-called dark fibers take advantage of synergistic installations. Their small size, ease of manipulation and gigantic bandwidths (in terabytes) allows for economic installation in anticipation of future use. Thus for rural America a strategy can evolve in which satellites provide an intermediate solution to high speed data communication while the terrestrial fiber-optic infrastructure catches up. PMID:11347427

  20. Prevalence and Risk Factors for Depressive Reaction among Resident Survivors after the Tsunami following the Great East Japan Earthquake, March 11, 2011

    PubMed Central

    Matsubara, Chieko; Murakami, Hitoshi; Imai, Koubun; Mizoue, Tetsuya; Akashi, Hidechika; Miyoshi, Chiaki; Nakasa, Tamotsu

    2014-01-01

    Objectives The Great East Japan Earthquake caused a gigantic tsunami which devastated coastal areas of northern Japan on 11 March 2011. Despite the large number of ‘resident survivors’ who continued to reside in their damaged houses on the second or upper floors, research on the mental health of these individuals has been limited. This study explored the prevalence of depressive reaction and risk factors for depressive reaction among these resident survivors. Methods A cross-sectional household health support needs screening was conducted for resident survivors in Higashi-Matsushima city, Miyagi prefecture, two to four months after the tsunami. The health interview that was conducted including mental status, assessed by the Patient Health Questionnaire-2 (PHQ-2). Results Of 5,454 respondents, 8.1% had depressive reaction. After adjustment by the number of weeks from the tsunami and the mortality rate at each respondent's place of residence, depressive reaction was significantly associated with house flooding below or above the ground floor (odds ratios of 1.92, 2.36, respectively), the unavailability of gas supply (odds ratio, 1.67), being female (odds ratio, 1.47), middle aged or elderly (odds ratios of 2.41, 2.42, respectively), regular intake of psychotropic medicine(s) since before the tsunami (odds ratio, 2.53) and the presence of one to five or more than six cohabiters (odds ratios of 0.61, 0.52, respectively). Conclusions The results suggest a considerable psychological burden (depressive reaction) following the tsunami among resident survivors. Special supports for families with psychiatric problems need to be considered among resident survivors. Restoration of lifeline utilities and the strengthening of social ties of persons living alone may help prevent depressive reaction among resident survivors after a tsunami. PMID:25279563

  1. Earthquake calamity warning from space station: orbital dynamics coupling geology mantle convection

    NASA Astrophysics Data System (ADS)

    Szu, Harold H.; Liu, Han-Shou

    2009-04-01

    It is not surprising that the earthquakes happened among clashing tectonic plate boundaries where numerous earthquake stations exist. Then, why do we need more? The significance of Sichuan and Tongshan earthquakes of China is a wakeup call that major earthquakes of logarithmic Richter scales beyond 7 could happen exactly within a single tectonic plate surprisingly. Thus, the previous border surveillance is broadened to areas coverage. Judging the success of archival survey of NASA with the gravitational potential by Liu et al., we review a unified earthquakes theory covering both the peripheral and the central plate in this paper, so that we can take seriously the need of a comprehensive global surveillance of natural calamity in the Space. The earth surface crust, like a kitchen kettle lid, covers tightly the melted mantle rock layer, like a pea soup cooking in the kettle. Given the time they will all become bubbling, rattling & shaking, known as the Bernard instability. This instability is ubiquitous for any liquid state matter being heated from below, if and only if it has a real positive thermal expansion coefficient. Likewise, the earth mantle is being cooked from below by an enormously hot fireball of the size of a moon. The heat comes from the radioactive decay confined within the core over eon's age. Due to the enormous gravitation attraction being always real positive and additive, the inner core is bifurcated into 2 regimes, a heat-melted liquid metal regime, where the earth magnetic field is produced and predicted by Faraday induction law. And further inside there exists a tightly squeezed solid metal ball regime, due to the gigantic weight compression, as confirmed by sonar experiments. The complexity of earth Bernard instability is due to the extra rotational Coriolis force that makes the up-down thermal convection side-way, creating the mass imbalance and permitting in-situ measurements feasible at a distance.

  2. Crustal nature and origin of the Russian Altai: Implications for the continental evolution and growth of the Central Asian Orogenic Belt (CAOB)

    NASA Astrophysics Data System (ADS)

    Cai, Keda; Sun, Min; Buslov, M. M.; Jahn, Bor-ming; Xiao, Wenjiao; Long, Xiaoping; Chen, Huayong; Wan, Bo; Chen, Ming; Rubanova, E. S.; Kulikova, A. V.; Voytishek, E. E.

    2016-04-01

    The Central Asian Orogenic Belt is a gigantic tectonic collage of numerous accreted terranes. However, its geodynamic evolution has been hotly debated primarily due to incomplete knowledge on the nature of these enigmatic terranes. This work presents new detrital zircon U-Pb and Hf isotopic data to constrain the crustal nature and origin of the Russian Altai, a critical segment of Altai-Mongolian terrane. The youngest zircon 206Pb/238U ages of 470 Ma constrain that the Terekta Formation, previously envisaged as Precambrian basement, was actually deposited after the Middle Ordovician. As for the three more sedimentary sequences above the Terekta Formation, they have youngest zircon 206Pb/238U ages of 425 Ma, 440 Ma and 380 Ma, respectively, indicating their depositions likely in the Late Silurian to Devonian. From all analyses, it is noted that many zircon U-Pb ages cluster at ca. 520 Ma and ca. 800 Ma, and these zircons display oscillatory zoning and have subhedral to euhedral morphology, which, collectively, suggests that adjacent Neoproterozoic to Paleozoic igneous rocks were possibly dominant in the sedimentary provenance. Additionally, a few rounded Archean to Mesoproterozoic zircon grains are characterized by complex texture, which are interpreted as recycling materials probably derived from the Tuva-Mongolian microcontinent. Precambrian rocks have not been identified in the Russian Altai, Chinese Altai and Mongolian Altai so far, therefore, Precambrian basement may not exist in the Altai-Mongolian terrane, but this terrane probably represents a large subduction-accretion complex built on the margin of the Tuva-Mongolian microcontinent in the Early Paleozoic. Multiple episodes of ridge-trench interaction may have caused inputs of mantle-derived magmas to trigger partial melting of the newly accreted crustal materials, which contributed to the accretionary complex. During accretionary orogenesis of the CAOB, formation of such subduction-accretion complex is

  3. Creative strategies of businesses with the holistic eigensolution in manufacturing industries

    NASA Astrophysics Data System (ADS)

    Zeichen, Gerfried; Huray, Paul G.

    1998-10-01

    It is a mission of this contribution to recognize and synthesize all the efforts in industry and in management science to strengthen our techniques and tools for successfully solving increasingly complex leadership problems in manufacturing industries. With the high standard of the work sharing method--the so called Taylorism principle--for cost efficient and mass production, invented at the beginning of the 20th century and the opening of the world market for global sales of goods and services a gigantic progress in living standards was reached. But at the beginning of the 21st century we are needing new ideas and methods for the guidance of overcoming increasing complexity. The holistic eigensolution presents a new operational framework for viewing and controlling the behavior of businesses. In contrast to the traditional process for viewing complex business systems through the intricate analysis of every part of that system, the authors have employed a technique used by physicists to understand the characteristic of `eigen' behaviors of complex physical systems. This method of systems analysis is achieved by observing interactions between the parts in a whole. This kind of analysis has a rigorous mathematical foundation in the physical world and it can be employed to understand most natural phenomena. Within a holistic framework, the observer is challenged to view the system form just the right perspective so that characteristic eigenmodes reveal themselves. The conclusion of the article describes why exactly the intelligent manufacturing science--especially in a broader sense--has the responsibility and chance to develop the holistic eigensolution framework as a Taylorism II-principle for the 21st century.

  4. Visions of our Planet's Atmosphere, Land and Oceans: NASA/NOAA Electronic-Theater 2002. Spectacular Visualizations of our Blue Marble

    NASA Technical Reports Server (NTRS)

    Hasler, A. F.; Starr, David (Technical Monitor)

    2002-01-01

    Spectacular Visualizations of our Blue Marble The NASA/NOAA Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to the 2002 Winter Olympic Stadium Site of the Olympic Opening and Closing Ceremonies in Salt Lake City. Fly in and through Olympic Alpine Venues using 1 m IKONOS "Spy Satellite" data. Go back to the early weather satellite images from the 1960s and see them contrasted with the latest US and international global satellite weather movies including hurricanes & "tornadoes". See the latest visualizations of spectacular images from NASA/NOAA remote sensing missions like Terra, GOES, TRMM, SeaWiFS, Landsat 7 including new 1 - min GOES rapid scan image sequences of Nov 9th 2001 Midwest tornadic thunderstorms and have them explained. See how High-Definition Television (HDTV) is revolutionizing the way we communicate science. (In cooperation with the American Museum of Natural History in NYC). See dust storms in Africa and smoke plumes from fires in Mexico. See visualizations featured on the covers of Newsweek, TIME, National Geographic, Popular Science & on National & International Network TV. New computer software tools allow us to roam & zoom through massive global images e.g. Landsat tours of the US, and Africa, showing desert and mountain geology as well as seasonal changes in vegetation. See animations of the polar ice packs and the motion of gigantic Antarctic Icebergs from SeaWinds data. Spectacular new visualizations of the global atmosphere & oceans are shown. See vertexes and currents in the global oceans that bring up the nutrients to feed tiny algae and draw the fish, whales and fisherman. See the how the ocean blooms in response to these currents and El Nicola Nina climate changes. See the city lights, fishing fleets, gas flares and biomass burning of the Earth at night observed by the "night-vision" DMSP military satellite.

  5. Twisting Tourniquet© Technique: introducing Schnogh, a novel device and its effectiveness in treating primary and secondary lymphedema of extremities

    PubMed Central

    Chanwimalueang, Narumon; Ekataksin, Wichai; Piyaman, Parkpoom; Pattanapen, Gedsuda; Hanboon, Borimas K

    2015-01-01

    Twisting Tourniquet© or in Thai “Schnogh” is a new invention for compression therapy of lymphedema. Twisting Tourniquet© Technique (TTT) is totally noninvasive for lymphedema management. After the amazing successful evidence in the first series of 28 patients, we have conducted preliminary studies in lymphedema clinics. It was found that the combination of gradually increasing constriction force by Schnogh until desired pressure was reached and maintained for 15 min, followed by a 5-min release, doing repeatedly this compression-decompression for at least 10 sessions a day, can generate acceptable results. The aim of the study was to evaluate the scientific effectiveness and establish a treatment protocol of TTT proposed as a therapeutic approach for clinical management of lymphedema. During 2006–2013, from over 3500 patients, 647 with primary/secondary lymphedema passed inclusion criteria, 307 for upper, and 340 for lower extremity. In the 5-day course of TTT, each day patients underwent 10 sessions of a 15-min compression followed by a 5-min decompression. Vegan diet was encouraged as an adjuvant therapy. Among lymphedema patients whose spectrum of edema severity ranged from mild to gigantic, TTT yielded an average volume reduction rate (VR) at 50.2% and 55.6%, making the average edema reduction volume attained at 463 and 1856 mL for upper and lower limb, respectively. The uniformed practice by Schnogh which supports a continual compression–decompression maneuver over 3.5 h daily for five consecutive days could induce an average VR at above half of the swelling in extremities of 647 patients. Schnogh is therefore effective in clinical management of lymphedema under TTT treatment of fibroblastic interstitium. PMID:26247407

  6. Electric jets following the occurrence of sprites

    NASA Astrophysics Data System (ADS)

    Lee, L.; Chou, J.; Huang, S.; Chang, S.; Wu, Y.; Lee, Y.; Kuo, C.; Chen, A. B.; Su, H.; Hsu, R.; Frey, H. U.; Mende, S. B.; Takahashi, Y.; Lee, L.

    2010-12-01

    Sprites are discharges occurring at the altitudes ~40 to 90 km, which are usually associated with positive cloud-to-ground lightning (+CGs). Electric jets, which include blue jets (BJs) with the terminal altitude of ~40km and gigantic jets (GJs) emanating to the lower ionosphere, are upward discharges from the cloud tops toward the upper atmosphere. From previous ground observations, it has been reported that the secondary discharges (“palm-tree” [Heavner, 2000] or “sprite-initiated secondary TLEs” [Marshall and Inan, 2007]) following sprites occurred in altitudes between the cloud top and the bottom of the sprite. From July 2004 to June 2010, ISUAL has recorded dozens of events which resemble the secondary TLEs. From image and photometric data recorded by ISUAL, all these secondary TLEs have the characteristics of jets, so we call these events “secondary jets”. These secondary jets are categorized into two groups according to their emanating horizontal positions in relative to the sprites. Group-I secondary jets occurred in the cloud top region which is directly below the sprites. The terminal altitude is ~ 40-50km for most of group-I secondary jets. Several group-I secondary jets appear to originate from the cloud top region below the symmetric center of the clustering sprites and then propagate toward the lower ionosphere. While the group-II secondary jets originate from region outside the shielding area of the clustering sprites. In this paper, the image and the photometric characteristics of the secondary jets will be presented and the possible generating mechanisms will be discussed.

  7. The water balance components of undisturbed tropical woodlands in the Brazilian Cerrado

    NASA Astrophysics Data System (ADS)

    Oliveira, P. T. S.; Wendland, E.; Nearing, M. A.; Scott, R. L.; Rosolem, R.; da Rocha, H. R.

    2014-11-01

    Deforestation of the Brazilian Cerrado region has caused major changes in hydrological processes. These changes in water balance components are still poorly understood, but are important for making land management decisions in this region. To understand pre-deforestation conditions, we determined the main components of the water balance for an undisturbed tropical woodland classified as "cerrado sensu stricto denso". We developed an empirical model to estimate actual evapotranspiration (ET) by using flux tower measurements and, vegetation conditions inferred from the enhanced vegetation index and reference evapotranspiration. Canopy interception, throughfall, stemflow, surface runoff, and water table level were assessed from ground measurements. We used data from two Cerrado sites, "Pé de Gigante" - PDG and "Instituto Arruda Botelho" - IAB. Flux tower data from the PDG site collected from 2001 to 2003 was used to develop the empirical model to estimate ET. The other hydrological processes were measured at the field scale between 2011 and 2014 in the IAB site. The empirical model showed significant agreement (R2= 0.73) with observed ET at the daily scale. The average values of estimated ET at the IAB site ranged from 1.91 to 2.60 mm d-1 for the dry and wet season, respectively. Canopy interception ranged from 4 to 20% and stemflow values were approximately 1% of gross precipitation. The average runoff coefficient was less than 1%, while Cerrado deforestation has the potential to increase that amount up to 20 fold. As relatively little excess water runs off (either by surface water or groundwater) the water storage may be estimated by the difference between precipitation and evapotranspiration. Our results provide benchmark values of water balance dynamics in the undisturbed Cerrado that will be useful to evaluate past and future land cover and land use changes for this region.

  8. The water balance components of undisturbed tropical woodlands in the Brazilian cerrado

    NASA Astrophysics Data System (ADS)

    Oliveira, P. T. S.; Wendland, E.; Nearing, M. A.; Scott, R. L.; Rosolem, R.; da Rocha, H. R.

    2015-06-01

    Deforestation of the Brazilian cerrado region has caused major changes in hydrological processes. These changes in water balance components are still poorly understood but are important for making land management decisions in this region. To better understand pre-deforestation conditions, we determined the main components of the water balance for an undisturbed tropical woodland classified as "cerrado sensu stricto denso". We developed an empirical model to estimate actual evapotranspiration (ET) by using flux tower measurements and vegetation conditions inferred from the enhanced vegetation index and reference evapotranspiration. Canopy interception, throughfall, stemflow, surface runoff, and water table level were assessed from ground measurements. We used data from two cerrado sites, Pé de Gigante (PDG) and Instituto Arruda Botelho (IAB). Flux tower data from the PDG site collected from 2001 to 2003 were used to develop the empirical model to estimate ET. The other hydrological processes were measured at the field scale between 2011 and 2014 at the IAB site. The empirical model showed significant agreement (R2 = 0.73) with observed ET at the daily timescale. The average values of estimated ET at the IAB site ranged from 1.91 to 2.60 mm day-1 for the dry and wet seasons, respectively. Canopy interception ranged from 4 to 20 % and stemflow values were approximately 1 % of the gross precipitation. The average runoff coefficient was less than 1 %, while cerrado deforestation has the potential to increase that amount up to 20-fold. As relatively little excess water runs off (either by surface water or groundwater), the water storage may be estimated by the difference between precipitation and evapotranspiration. Our results provide benchmark values of water balance dynamics in the undisturbed cerrado that will be useful to evaluate past and future land-cover and land-use changes for this region.

  9. Thermal and electrical conductivity of iron at Earth's core conditions.

    PubMed

    Pozzo, Monica; Davies, Chris; Gubbins, David; Alfè, Dario

    2012-05-17

    The Earth acts as a gigantic heat engine driven by the decay of radiogenic isotopes and slow cooling, which gives rise to plate tectonics, volcanoes and mountain building. Another key product is the geomagnetic field, generated in the liquid iron core by a dynamo running on heat released by cooling and freezing (as the solid inner core grows), and on chemical convection (due to light elements expelled from the liquid on freezing). The power supplied to the geodynamo, measured by the heat flux across the core-mantle boundary (CMB), places constraints on Earth's evolution. Estimates of CMB heat flux depend on properties of iron mixtures under the extreme pressure and temperature conditions in the core, most critically on the thermal and electrical conductivities. These quantities remain poorly known because of inherent experimental and theoretical difficulties. Here we use density functional theory to compute these conductivities in liquid iron mixtures at core conditions from first principles--unlike previous estimates, which relied on extrapolations. The mixtures of iron, oxygen, sulphur and silicon are taken from earlier work and fit the seismologically determined core density and inner-core boundary density jump. We find both conductivities to be two to three times higher than estimates in current use. The changes are so large that core thermal histories and power requirements need to be reassessed. New estimates indicate that the adiabatic heat flux is 15 to 16 terawatts at the CMB, higher than present estimates of CMB heat flux based on mantle convection; the top of the core must be thermally stratified and any convection in the upper core must be driven by chemical convection against the adverse thermal buoyancy or lateral variations in CMB heat flow. Power for the geodynamo is greatly restricted, and future models of mantle evolution will need to incorporate a high CMB heat flux and explain the recent formation of the inner core. PMID:22495307

  10. Testing the 'island rule' for a tenebrionid beetle (Coleoptera, Tenebrionidae)

    NASA Astrophysics Data System (ADS)

    Palmer, Miquel

    2002-05-01

    Insular populations and their closest mainland counterparts commonly display body size differences that are considered to fit the island rule, a theoretical framework to explain both dwarfism and gigantism in isolated animal populations. The island rule is used to explain the pattern of change of body size at the inter-specific level. But the model implicitly makes also a prediction for the body size of isolated populations of a single species. It suggests that, for a hypothetical species covering a wide range of island sizes, there exists a specific island size where this species reaches the largest body size. Body size would be small (in relative terms) in the smallest islets of the species range. It would increase with island size, and reach a maximum at some specific island size. However, additional increases from such a specific island size would instead promote body size reduction, and small (in relative terms) body sizes would be found again on the largest islands. The biogeographical patterns predicted by the island rule have been described and analysed for vertebrates only (mainly mammals), but remain largely untested for insects or other invertebrates. I analyse here the pattern of body size variation between seven isolated insular populations of a flightless beetle, Asida planipennis (Coleoptera, Tenebrionidae). This is an endemic species of Mallorca, Menorca and a number of islands and islets in the Balearic archipelago (western Mediterranean). The study covers seven of the 15 known populations (i.e., there are only 15 islands or islets inhabited by the species). The populations studied fit the pattern advanced above and we could, therefore, extrapolate the island rule to a very different kind of organism. However, the small sample size of some of the populations invites some caution at this early stage.

  11. An analysis of five negative sprite-parent discharges and their associated thunderstorm charge structures

    NASA Astrophysics Data System (ADS)

    Boggs, Levi D.; Liu, Ningyu; Splitt, Michael; Lazarus, Steven; Glenn, Chad; Rassoul, Hamid; Cummer, Steven A.

    2016-01-01

    In this study we analyze the discharge morphologies of five confirmed negative sprite-parent discharges and the associated charge structures of the thunderstorms that produced them. The negative sprite-parent lightning took place in two thunderstorms that were associated with a tropical disturbance in east central and south Florida. The first thunderstorm, which moved onshore in east central Florida, produced four of the five negative sprite-parent discharges within a period of 17 min, as it made landfall from the Atlantic Ocean. These negative sprite-parents were composed of bolt-from-the-blue (BFB), hybrid intracloud-negative cloud-to-ground (IC-NCG), and multicell IC-NCGs discharges. The second thunderstorm, which occurred inland over south Florida, produced a negative sprite-parent that was a probable hybrid IC-NCG discharge and two negative gigantic jets (GJs). Weakened upper positive charge with very large midlevel negative charge was inferred for both convective cells that initiated the negative-sprite-parent discharges. Our study suggests tall, intense convective systems with high wind shear at the middle to upper regions of the cloud accompanied by low cloud-to-ground (CG) flash rates promote these charge structures. The excess amount of midlevel negative charge results in these CG discharges transferring much more charge to ground than typical negative CG discharges. We find that BFB discharges prefer an asymmetrical charge structure that brings the negative leader exiting the upper positive charge region closer to the lateral positive screening charge layer. This may be the main factor in determining whether a negative leader exiting the upper positive region of the thundercloud forms a BFB or GJ.

  12. Familial Isolated Pituitary Adenomas (FIPA) and the Pituitary Adenoma Predisposition due to Mutations in the Aryl Hydrocarbon Receptor Interacting Protein (AIP) Gene

    PubMed Central

    Aaltonen, Lauri A.; Daly, Adrian F.

    2013-01-01

    Pituitary adenomas are one of the most frequent intracranial tumors and occur with a prevalence of approximately 1:1000 in the developed world. Pituitary adenomas have a serious disease burden, and their management involves neurosurgery, biological therapies, and radiotherapy. Early diagnosis of pituitary tumors while they are smaller may help increase cure rates. Few genetic predictors of pituitary adenoma development exist. Recent years have seen two separate, complimentary advances in inherited pituitary tumor research. The clinical condition of familial isolated pituitary adenomas (FIPA) has been described, which encompasses the familial occurrence of isolated pituitary adenomas outside of the setting of syndromic conditions like multiple endocrine neoplasia type 1 and Carney complex. FIPA families comprise approximately 2% of pituitary adenomas and represent a clinical entity with homogeneous or heterogeneous pituitary adenoma types occurring within the same kindred. The aryl hydrocarbon receptor interacting protein (AIP) gene has been identified as causing a pituitary adenoma predisposition of variable penetrance that accounts for 20% of FIPA families. Germline AIP mutations have been shown to associate with the occurrence of large pituitary adenomas that occur at a young age, predominantly in children/adolescents and young adults. AIP mutations are usually associated with somatotropinomas, but prolactinomas, nonfunctioning pituitary adenomas, Cushing disease, and other infrequent clinical adenoma types can also occur. Gigantism is a particular feature of AIP mutations and occurs in more than one third of affected somatotropinoma patients. Study of pituitary adenoma patients with AIP mutations has demonstrated that these cases raise clinical challenges to successful treatment. Extensive research on the biology of AIP and new advances in mouse Aip knockout models demonstrate multiple pathways by which AIP may contribute to tumorigenesis. This review assesses

  13. Cometary Knots Around A Dying Star

    NASA Technical Reports Server (NTRS)

    1994-01-01

    These gigantic, tadpole-shaped objects are probably the result of a dying star's last gasps. Dubbed 'cometary knots' because their glowing heads and gossamer tails resemble comets, the gaseous objects probably were formed during a star's final stages of life. Hubble astronomer C. Robert O'Dell and graduate student Kerry P. Handron of Rice University in Houston, Texas discovered thousands of these knots with the Hubble Space Telescope while exploring the Helix nebula, the closest planetary nebula to Earth at 450 light-years away in the constellation Aquarius. Although ground-based telescopes have revealed such objects, astronomers have never seen so many of them. The most visible knots all lie along the inner edge of the doomed star's ring, trillions of miles away from the star's nucleus. Although these gaseous knots appear small, they're actually huge. Each gaseous head is at least twice the size of our solar system; each tail stretches for 100 billion miles, about 1,000 times the distance between the Earth and the Sun. Astronomers theorize that the doomed star spews hot, lower-density gas from its surface, which collides with cooler, higher-density gas that had been ejected 10,000 years before. The crash fragments the smooth cloud surrounding the star into smaller, denser finger-like droplets, like dripping paint. This image was taken in August, 1994 with Hubble's Wide Field Planetary Camera 2. The red light depicts nitrogen emission ([NII] 6584A); green, hydrogen (H-alpha, 6563A); and blue, oxygen (5007A).

  14. The medical association activity and pediatric care after the earthquake disaster in Fukushima.

    PubMed

    Kikuchi, Shintaro; Kikuchi, Tatsuo

    2012-01-01

    On March 11, 2011, a gigantic earthquake struck eastern Japan. Utilities such as electricity, water, gas and telecommunication were interrupted. In Koriyama, the City Hall collapsed and government administration offices had to be moved to a nearby baseball stadium that had been designed to include facilities for use during a pandemic. An operations center was set up in this stadium. As members of the Koriyama Medical Association, we following the disaster protocol and set up our operations center in the Koriyama Medical Care Hospital. One large hospital with 280 inpatients and another hospital with 150 inpatients had been heavily damaged. Transfer of those patients to other hospitals without the use of telecommunications was extremely difficult. Many doctors in member hospitals and clinics went out of their way to cooperate throughout the crisis. Up to 5,000 people from the radiation evacuation zone were rushed to Koriyama. They stayed in schools and community centers, where we provided them with healthcare. Even in Koriyama, which is 60 km away from the Fukushima nuclear power plant, radiation levels were high, especially for the first few weeks. Citizens were advised to stay at home and keep their doors and windows closed. These drastic measures and frequent earthquake aftershocks were very stressful, especially for children. To help prevent children from developing posttraumatic stress disorder (PTSD), a project team composed of various groups caring for children was developed, and this team took action to protect children. Through these efforts we hoped to provide children with an appropriate environment to grow normally, even in a zone of persistent low-level radiation. We demonstrated once again that our members' long history of mutual assistance and cooperation with the administration was the main cornerstone to overcome the crisis. PMID:22410536

  15. Satellite Measured Solar Protons from 1963-1993 and Their Influence on Ozone in a Changing Stratosphere

    NASA Technical Reports Server (NTRS)

    Jackman, Charles H.; Fleming, Eric L.; Vitt, Francis M.; Einaudi, Franco (Technical Monitor)

    2000-01-01

    The fluxes of solar protons have been measured by a series of Interplanetary Monitoring Platform (IMP) satellites since 1963. Eight IMP satellites have been launched since 1963 providing excellent coverage of solar protons with energies from a few MeV to several hundred MeV. IMP 8, launched in October 1973, continues to provide proton measurements, twenty-six and a half (26 1/2) years after launch. These high energy solar protons rain down on the earth's polar atmosphere sporadically, primarily during solar proton events (SPEs) which typically last a few days. Solar protons with energies of 30 MeV or greater are capable of reaching the stratosphere and causing increases in odd nitrogen (NO(y)) constituents at polar latitudes ($>$ 60 degrees geomagnetic) which last for several months to years past the events. These enhanced NO(y) species can lead to significant upper stratospheric ozone depletions $ greater than $10\\% during the gigantic SPEs that occurred in August 1972 and October 1989. We studied the effects of SPEs on the stratosphere from 1963 to the mid 1990s. During this time period, the stratospheric chlorine levels changed from relatively small in 1963 ($\\sim$ 1 ppbv) to fairly substantial amounts in the mid-1990s ($\\sim$ 3.3 ppbv). Our recently improved two-dimensional chemistry and transport atmospheric model was used to compute the effects of SPEs in this changing stratosphere. The long-lived SPE-produced NO(y) constituents were transported to lower stratospheric levels during winter after the events and caused impacts in the middle and lower stratosphere. Generally, the SPEs resulted in a decrease in ozone. However, during periods of high halogen loading these impacts resulted in interference with the chlorine and bromine loss cycles for ozone destruction. This interference actually led to a predicted total ozone increase that was especially notable in the time period 1992-4, a few years after the October 1989 SPE.

  16. Immediate Impact of Elevated Nitrogen Input on Trace Gases Emissions in an old-Growth Lowland Forest in Panama

    NASA Astrophysics Data System (ADS)

    Wullaert, H.; Veldkamp, E.; Corre, M. D.

    2007-05-01

    In tropical areas, nitrogen (N) emission, transport and deposition are projected to increase rapidly in the next decades. In this study, the consequences of elevated N input on trace gases emissions from a tropical lowland forest soil were evaluated. The study site is located in Gigante Peninsula, Panama, which included control and N addition treatments each with four replicate plots. Urea-N was applied twice in 2006 (April 28 and June 6) at a rate of 31.25 kg N ha-1 each application. Nitrous oxide (N2O), nitric oxide (NO), carbon dioxide (CO2) and methane (CH4) fluxes were intensively measured prior to and until one month after the second N application; this measurement period was within the beginning of the rainy season. We observed significantly higher NO emissions from the N-fertilized than the control plots, but N2O, CO2 and CH4 fluxes did not differ. The increased NO fluxes were largely observed during the first week after the second fertilization, when water-filled pore space (WFPS) has increased as the rainy season progressed. N2O emissions could possibly increase with N addition when soil moisture further increase into the rainy season. The significant correlation between N2O + NO fluxes and NH4+ levels and the range of WFPS (40-60%) indicated that N trace gases were possibly predominantly produced by nitrification. The fertilizer- induced N oxide emission was 3% of the applied N. The CO2 and CH4 fluxes indicated that initial N addition did not bring detectable change in microbial decomposition and root respiration for CO2 emissions and in CH4 consumption and production for CH4 fluxes, at least during the early rainy season covered in our measurement.

  17. The mystical effects of dermatological vehicles.

    PubMed

    Surber, Christian; Smith, Eric W

    2005-01-01

    Topical treatment of the skin is as old as the evolution of man. Instinctively, we try to treat a skin injury or irritation with cooling or soothing substances. Even animals lick their wounds, trusting instinctively in the healing power of saliva. When did this archaic pattern of treatment take the gigantic leap from folk medicine to modern drug therapy? This text illustrates the evolution of topical dermatological vehicles, their application (guidelines) and future use. In particular, a phenomenon that has so far been ignored in product development and clinical testing is the vehicle metamorphosis. In clinical and experimental situations, most dermatological vehicles undergo considerable changes after they have been removed from the primary container and are applied to the skin. Subsequently, the initial structural matrix, and the quantitative composition of the vehicle, will most likely change during and after the mechanical shear associated with application of the product and/or evaporation of ingredients. This natural, but highly dynamic process will generate mini-environments for the active moiety that are difficult to predict and that are crucial to the fate of the active moiety. Despite the reasonable wishes of formulators, clinicians, patients and customers, there are still no universal vehicles. Each drug, at each concentration, requires a different vehicle for optimized therapy. Stability and compatibility of excipients and active moiety are crucial for any commercially available pharmaceutical or cosmetic formulation, together with local and systemic safety of all components. Nonetheless, more diverse and molecularly complex classes of new dermatological vehicles are continuously being researched and refined. The scientific progress has been remarkable when one considers the simple emulsion mixtures that were commonplace in dermatological therapy and still persist to this day in commercial products. It is to be hoped that the result of these research

  18. Observations of ``Gas-Rich'' Disks

    NASA Astrophysics Data System (ADS)

    Ménard, François

    2004-06-01

    Accretion disks are pivotal elements in the formation and early evolution of solar-like stars. On top of supplying the raw material, their internal conditions also regulate the formation of planets. Their study therefore holds the key to solve the mystery of the formation of our Solar System. This chapter focuses on observational studies of circumstellar disks associated with pre-main sequence solar-like stars. The direct measurement of disk parameters poses an obvious challenge: at the distance of typical star forming regions (e.g., ~140pc for Taurus), a planetary system like ours (with diameter ~= 50AU out to Pluto, but excluding the Kuiper belt) subtends only 0.35''. Yet its surface brightness is low in comparison to the bright central star and high angular and high contrast imaging techniques are required if one hopes to resolve and measure these protoplanetary disks. Fortunately, capable instruments providing 0.1'' resolution or better and high contrast have been available for just about 10 years now. They are covering a large part of the electromagnetic spectrum, from the UV/Optical with HST and the near-infrared from ground-based adaptive optics systems, to the millimetric range with long-baseline radio interferometers. It is therefore not surprising that our knowledge of the structure of the disks surrounding low-mass stars has made a gigantic leap forward in the last decade. In the following pages I will attempt to give an overview of the structural and physical parameters of protoplanetary disks that can be estimated today from direct observations.

  19. Observations of Protostellar Disks

    NASA Astrophysics Data System (ADS)

    Ménard, F.

    2004-12-01

    Accretion disks are pivotal elements in the formation and early evolution of solar-like stars. On top of supplying the raw material, their internal conditions also regulate the formation of planets. Their study therefore holds the key to solve the mystery of the formation of our Solar System. This chapter focuses on observational studies of circumstellar disks associated with pre-main sequence solar-like stars. The direct measurement of disk parameters poses an obvious challenge: at the distance of typical star forming regions (e.g., ˜140pc for Taurus), a planetary system like ours (with diameter ≃ 50AU out to Pluto, but excluding the Kuiper belt) subtends only 0.35". Yet its surface brightness is low in comparison to the bright central star and high angular and high contrast imaging techniques are required if one hopes to resolve and measure these protoplanetary disks. Fortunately, capable instruments providing 0.1" resolution or better and high contrast have been available for just about 10 years now. They are covering a large part of the electromagnetic spectrum, from the UV/Optical with HST and the near-infrared from ground-based adaptive optics systems, to the millimetric range with long-baseline radio interferometers. It is therefore not surprising that our knowledge of the structure of the disks surrounding low-mass stars has made a gigantic leap forward in the last decade. In the following pages I will attempt to give an overview of the structural and physical parameters of protoplanetary disks that can be estimated today from direct observations.

  20. Reproductive Biology and Its Impact on Body Size: Comparative Analysis of Mammalian, Avian and Dinosaurian Reproduction

    PubMed Central

    Werner, Jan; Griebeler, Eva Maria

    2011-01-01

    Janis and Carrano (1992) suggested that large dinosaurs might have faced a lower risk of extinction under ecological changes than similar-sized mammals because large dinosaurs had a higher potential reproductive output than similar-sized mammals (JC hypothesis). First, we tested the assumption underlying the JC hypothesis. We therefore analysed the potential reproductive output (reflected in clutch/litter size and annual offspring number) of extant terrestrial mammals and birds (as “dinosaur analogs”) and of extinct dinosaurs. With the exception of rodents, the differences in the reproductive output of similar-sized birds and mammals proposed by Janis and Carrano (1992) existed even at the level of single orders. Fossil dinosaur clutches were larger than litters of similar-sized mammals, and dinosaur clutch sizes were comparable to those of similar-sized birds. Because the extinction risk of extant species often correlates with a low reproductive output, the latter difference suggests a lower risk of population extinction in dinosaurs than in mammals. Second, we present a very simple, mathematical model that demonstrates the advantage of a high reproductive output underlying the JC hypothesis. It predicts that a species with a high reproductive output that usually faces very high juvenile mortalities will benefit more strongly in terms of population size from reduced juvenile mortalities (e.g., resulting from a stochastic reduction in population size) than a species with a low reproductive output that usually comprises low juvenile mortalities. Based on our results, we suggest that reproductive strategy could have contributed to the evolution of the exceptional gigantism seen in dinosaurs that does not exist in extant terrestrial mammals. Large dinosaurs, e.g., the sauropods, may have easily sustained populations of very large-bodied species over evolutionary time. PMID:22194835