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Sample records for condilomatosis vulvoperineal 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. Vulvoperineal Crohn's disease responsive to metronidazole*

    PubMed Central

    Rosmaninho, Aristóteles; Sanches, Madalena; Salgado, Marta; Alves, Rosário; Selores, Manuela

    2013-01-01

    Crohn's disease is a multisystem chronic granulomatous inflammatory disease that primarily affects the gastrointestinal tract. In the majority of the cases, the cutaneous manifestations follow the intestinal disease, but occasionally dermatological lesions are the inaugural event and may constitute the only sign of the disease. Vulvoperineal involvement is rare, may precede bowel symptoms by months to years and may go unrecognized. Due to the paucity of reports of Crohn's disease at this location and in the absence of randomized trials, there are no standard treatments for the cutaneous disease. We describe the case of a 47 year-old woman with vulvoperineal Crohn's disease without digestive involvement, that was successfully managed with metronidazole. PMID:24346884

  3. Pituitary gigantism: Causes and clinical characteristics.

    PubMed

    Rostomyan, Liliya; Daly, Adrian F; Beckers, Albert

    2015-12-01

    Acromegaly and pituitary gigantism are very rare conditions resulting from excessive secretion of growth hormone (GH), usually by a pituitary adenoma. Pituitary gigantism occurs when GH excess overlaps with the period of rapid linear growth during childhood and adolescence. Until recently, its etiology and clinical characteristics have been poorly understood. Genetic and genomic causes have been identified in recent years that explain about half of cases of pituitary gigantism. We describe these recent discoveries and focus on some important settings in which gigantism can occur, including familial isolated pituitary adenomas (FIPA) and the newly described X-linked acrogigantism (X-LAG) syndrome. PMID:26585365

  4. The evolution of floral gigantism.

    PubMed

    Davis, Charles C; Endress, Peter K; Baum, David A

    2008-02-01

    Flowers exhibit tremendous variation in size (>1000-fold), ranging from less than a millimeter to nearly a meter in diameter. Numerous studies have established the importance of increased floral size in species that exhibit relatively normal-sized flowers, but few studies have examined the evolution of floral size increase in species with extremely large flowers or flower-like inflorescences (collectively termed blossoms). Our review of these record-breakers indicates that blossom gigantism has evolved multiple times, and suggests that the evolutionary forces operating in these species may differ from their ordinary-sized counterparts. Surprisingly, rather than being associated with large-bodied pollinators, gigantism appears to be most common in species with small-bodied beetle or carrion-fly pollinators. Such large blossoms may be adapted to these pollinators because they help to temporarily trap animals, better facilitate thermal regulation, and allow for the mimicry of large animal carcasses. Future phylogenetic tests of these hypotheses should be conducted to determine if the transition to such pollination systems correlates with significant changes in the mode and tempo of blossom size evolution. PMID:18207449

  5. Dwarfism and gigantism in historical picture postcards.

    PubMed Central

    Enderle, A

    1998-01-01

    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. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:9764085

  6. 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

  7. 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

  8. 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

  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. 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. SN 2002bo was caught almost two weeks before reaching its maximum brightness, allowing astronomers to study its evolution. It has been the subject of intense monitoring by a world-wide network of telescopes. The conclusion was that SN 2002bo is a rather unusual Type Ia supernova [3]. The image presented here was taken in March 2003, i.e. about a year after the maximum of the supernova which is 50 times fainter on the image than a year before. While observing SN 2002bo in May 2002, a group of Italian astronomers discovered another supernova, SN 2002cv, on the other side of NGC 3190. Two supernovae of this type appearing nearly simultaneously in the same galaxy is a rare event, as normally astronomers expect only one such event per century in a galaxy. SN 2002cv was best visible at infrared wavelengths as it was superimposed on the dust lane of NGC 3190, and therefore hidden by a large quantity of dust. In fact, this supernova holds the record for the most obscured Type Ia event. The image was obtained with a total exposure time of 14 minutes only. Yet, with the amazing power of the Very Large Telescope, it reveals a large zoo of galaxies of varying morphologies. How many can you find? A high resolution image and its caption is available on this page.

  12. A gigantic feathered dinosaur from the lower cretaceous of China.

    PubMed

    Xu, Xing; Wang, Kebai; Zhang, Ke; Ma, Qingyu; Xing, Lida; Sullivan, Corwin; Hu, Dongyu; Cheng, Shuqing; Wang, Shuo

    2012-04-01

    Numerous feathered dinosaur specimens have recently been recovered from the Middle-Upper Jurassic and Lower Cretaceous deposits of northeastern China, but most of them represent small animals. Here we report the discovery of a gigantic new basal tyrannosauroid, Yutyrannus huali gen. et sp. nov., based on three nearly complete skeletons representing two distinct ontogenetic stages from the Lower Cretaceous Yixian Formation of Liaoning Province, China. Y. huali shares some features, particularly of the cranium, with derived tyrannosauroids, but is similar to other basal tyrannosauroids in possessing a three-fingered manus and a typical theropod pes. Morphometric analysis suggests that Y. huali differed from tyrannosaurids in its growth strategy. Most significantly, Y. huali bears long filamentous feathers, thus providing direct evidence for the presence of extensively feathered gigantic dinosaurs and offering new insights into early feather evolution. PMID:22481363

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

    PubMed Central

    Donnelly, Deirdre E; Morrison, Patrick J

    2014-01-01

    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

  14. 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

  15. Gigantic jets between a thundercloud and the ionosphere

    NASA Astrophysics Data System (ADS)

    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.

    2003-06-01

    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 ~16km) and the ionosphere at 90km 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.

  16. Avian-style respiration allowed gigantism in pterosaurs.

    PubMed

    Ruxton, Graeme

    2014-08-01

    Powered flight has evolved three times in the vertebrates: in the birds, the bats and the extinct pterosaurs. The largest bats ever known are at least an order of magnitude smaller than the largest members of the other two groups. Recently, it was argued that different scaling of wingbeat frequencies to body mass in birds and bats can help explain why the largest birds are larger than the largest bats. Here, I extend this argument in two ways. Firstly, I suggest that different respiratory physiologies are key to understanding the restriction on bat maximum size compared with birds. Secondly, I argue that a respiratory physiology similar to birds would have been a prerequisite for the gigantism seen in pterosaurs. PMID:24855669

  17. 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

  18. 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.

  19. 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 extensive pneumatization of the axial skeleton resulted from the evolution of an avian-style respiratory system, presumably at the base of Saurischia. An avian-style respiratory system would also have lowered the cost of breathing, reduced specific gravity, and may have been important in removing excess body heat. Another crucial innovation inherited from basal dinosaurs was a high BMR. This is required for fueling the high growth rate necessary for a multi-tonne animal to survive to reproductive maturity. The retention of the plesiomorphic oviparous mode of reproduction appears to have been critical as well, allowing much faster population recovery than in megaherbivore mammals. Sauropods produced numerous but small offspring each season while land mammals show a negative correlation of reproductive output to body size. This permitted lower population densities in sauropods than in megaherbivore mammals but larger individuals. Our work on sauropod dinosaurs thus informs us about evolutionary limits to body size in other groups of herbivorous terrestrial tetrapods. Ectothermic reptiles are strongly limited by their low BMR, remaining small. Mammals are limited by their extensive mastication and their vivipary, while ornithsichian dinosaurs were only limited by their extensive mastication, having greater average body sizes than mammals. PMID:21251189

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

    PubMed

    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

    2011-02-01

    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 extensive pneumatization of the axial skeleton resulted from the evolution of an avian-style respiratory system, presumably at the base of Saurischia. An avian-style respiratory system would also have lowered the cost of breathing, reduced specific gravity, and may have been important in removing excess body heat. Another crucial innovation inherited from basal dinosaurs was a high BMR. This is required for fueling the high growth rate necessary for a multi-tonne animal to survive to reproductive maturity. The retention of the plesiomorphic oviparous mode of reproduction appears to have been critical as well, allowing much faster population recovery than in megaherbivore mammals. Sauropods produced numerous but small offspring each season while land mammals show a negative correlation of reproductive output to body size. This permitted lower population densities in sauropods than in megaherbivore mammals but larger individuals. Our work on sauropod dinosaurs thus informs us about evolutionary limits to body size in other groups of herbivorous terrestrial tetrapods. Ectothermic reptiles are strongly limited by their low BMR, remaining small. Mammals are limited by their extensive mastication and their vivipary, while ornithsichian dinosaurs were only limited by their extensive mastication, having greater average body sizes than mammals. PMID:21251189

  1. 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

  2. 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

  3. Oxygen hypothesis of polar gigantism not supported by performance of Antarctic pycnogonids in hypoxia.

    PubMed

    Woods, H Arthur; Moran, Amy L; Arango, Claudia P; Mullen, Lindy; Shields, Chris

    2009-03-22

    Compared to temperate and tropical relatives, some high-latitude marine species are large-bodied, a phenomenon known as polar gigantism. A leading hypothesis on the physiological basis of gigantism posits that, in polar water, high oxygen availability coupled to low metabolic rates relieves constraints on oxygen transport and allows the evolution of large body size. Here, we test the oxygen hypothesis using Antarctic pycnogonids, which have been evolving in very cold conditions (-1.8-0 degrees C) for several million years and contain spectacular examples of gigantism. Pycnogonids from 12 species, spanning three orders of magnitude in body mass, were collected from McMurdo Sound, Antarctica. Individual sea spiders were forced into activity and their performance was measured at different experimental levels of dissolved oxygen (DO). The oxygen hypothesis predicts that, all else being equal, large pycnogonids should perform disproportionately poorly in hypoxia, an outcome that would appear as a statistically significant interaction between body size and oxygen level. In fact, although we found large effects of DO on performance, and substantial interspecific variability in oxygen sensitivity, there was no evidence for sizexDO interactions. These data do not support the oxygen hypothesis of Antarctic pycnogonid gigantism and suggest that explanations must be sought in other ecological or evolutionary processes. PMID:19129117

  4. Oxygen hypothesis of polar gigantism not supported by performance of Antarctic pycnogonids in hypoxia

    PubMed Central

    Woods, H. Arthur; Moran, Amy L.; Arango, Claudia P.; Mullen, Lindy; Shields, Chris

    2008-01-01

    Compared to temperate and tropical relatives, some high-latitude marine species are large-bodied, a phenomenon known as polar gigantism. A leading hypothesis on the physiological basis of gigantism posits that, in polar water, high oxygen availability coupled to low metabolic rates relieves constraints on oxygen transport and allows the evolution of large body size. Here, we test the oxygen hypothesis using Antarctic pycnogonids, which have been evolving in very cold conditions (−1.8–0°C) for several million years and contain spectacular examples of gigantism. Pycnogonids from 12 species, spanning three orders of magnitude in body mass, were collected from McMurdo Sound, Antarctica. Individual sea spiders were forced into activity and their performance was measured at different experimental levels of dissolved oxygen (DO). The oxygen hypothesis predicts that, all else being equal, large pycnogonids should perform disproportionately poorly in hypoxia, an outcome that would appear as a statistically significant interaction between body size and oxygen level. In fact, although we found large effects of DO on performance, and substantial interspecific variability in oxygen sensitivity, there was no evidence for size×DO interactions. These data do not support the oxygen hypothesis of Antarctic pycnogonid gigantism and suggest that explanations must be sought in other ecological or evolutionary processes. PMID:19129117

  5. 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 volcano, the flow spreads all over a large tectonic depression, forming a large inflated pahoehoe sheet flow. The flow continues downstream, always showing typical inflation features, forming a very long and narrow tongue, developed over the nearly flat Pampa plain (gradient 0.5%) with an average width of 3 km and a length of 120 km. A peculiar feature of this portion of the flow, apart from its exceptional length, is the very low width-to-length ratio. This is even more surprising if we consider that no pre-existing topographic feature (e.g. river channel, etc.) is responsible for this behaviour, which appears to be only the result of some kind of self-confinement mechanism. The structural, morphological and eruptive complexities of this volcanic structure are exceptional by themselves since there are no similar features both in the Andes calcalkaline volcanism or in the Patagonian basaltic plateaus and they pose problems even in the nomenclatural definition of the Payun Matru as an individual volcanic construct. Moreover, understanding the mechanisms responsible for the exceptional behaviour of this lava flow may provide new constraints on the physics of inflated pahoehoe flow emplacement. Results in this direction may also offer useful proxies for interpreting volcanic processes on terrestrial planets such as Mars and Venus, on which individual lava flows of similar shape and dimensions have been observed.

  6. Analysis of the first gigantic jet recorded over continental North America

    NASA Astrophysics Data System (ADS)

    van der Velde, Oscar A.; Lyons, Walter A.; Nelson, Thomas E.; Cummer, Steven A.; Li, Jingbo; Bunnell, James

    2007-10-01

    Two low-light cameras near Marfa, Texas, recorded a gigantic jet over northern Mexico on 13 May 2005 at approximately 0423:50 UTC. Assuming that the farthest of two candidate storm systems was its source, the bright lower channel ended in a fork at around 50-59 km height with the very dim upper branches extended to 69-80 km altitude. During the time window containing the jet, extremely low frequency magnetic field recordings show that there was no fast charge moment change larger than 50 coulomb times kilometers (C km) but there was a larger and slower charge moment change of 520 C km over 70 ms. The likely parent thunderstorm was a high-precipitation supercell cluster containing a persistent mesocyclone, with radar echo tops of at least 17 km. However, photogrammetric analysis suggests that the gigantic jet occurred over the forward flank downdraft region with echo tops of 14 km. This part of the supercell may have had an inverted-polarity charge configuration as evidenced by positive cloud-to-ground lightning flashes (+CG) dominating over negative flashes (-CG), while -CGs occurred under the downwind anvil. Four minutes before the gigantic jet, -CG activity practically ceased in this area, while +CG rates increased, culminating during the 20 s leading up to the gigantic jet with four National Lightning Detection Network-detected +CGs. A relative lull in lightning activity of both polarities was observed for up to 1.5 min after the gigantic jet. The maturing storm subsequently produced 30 sprites between 0454 and 0820 UTC, some associated with extremely large impulse charge moment change values.

  7. Observations of Seven Blue/Gigantic Jets above One Storm over the Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Liu, N.; Spiva, N.; Dwyer, J. R.; Rassoul, H.; Free, D. L.; Cummer, S. A.

    2013-12-01

    Blue/gigantic jets are electrical discharges developing from thundercloud tops and propagating to the upper atmosphere [e.g., Pasko et al., Nature, 416, 152, 2002; Su et al., Nature, 423, 973, 2003]. Not just producing an impressive display, gigantic jets establish a direct path of electrical contact between the upper troposphere and the lower ionosphere, capable of transferring a large amount of charge between them [Cummer et al., Nat. Geosci., 2, 617, 2009]. It has been suggested that they may play an important role in the earth's electrical environment [e. g., Pasko, Nature, 423, 927, 2003]. Upward discharges from thunderstorms like blue/gigantic jets are believed to originate from lightning leaders escaping from thunderclouds when the cloud's charges of different polarities are not balanced [Krehbiel et al., Nat. Geosci., 1, 233, 2008; Riousset et al., JGR, 115, A00E10, 2010]. On the evening of August 2, 2013, 4 gigantic jets, 2 blue jets and 1 blue starter were recorded within 26 min above a storm over the Atlantic Ocean by a low light level camera from the campus of Florida Institute of Technology. The events were also captured by two all-sky cameras: one again from the Florida Tech campus and the other from a nearby location. According to the NLDN data, positive intra-cloud flashes preceded all events except one gigantic jet. The distance between the observation site to the locations of the NLDN lightning discharges varies from 77 to 82 km. Optical signatures of intra-cloud discharge activities accompanied the events are clearly visible in the videos. The duration of each jet varies from about 300 ms to 1.2 s, and the 1.2 s duration is probably the longest that has been reported to date for jets. Rebrightening of gigantic jet structures occurs for at least two of the events. The upper terminal altitude of the 4 gigantic jets is greater than 76-81 km, the 2 blue jets reach about 48 and 51 km altitude, respectively, and the blue starter reaches 24 km altitude. The altitude of cloud tops varies from 14 to 20 km. All events exhibit a tree-like structure and develop in an impulsive manner. Similar to other observations of gigantic jets, bright beads appear at the tops of the gigantic jets. The impulsive upward propagation of the jets together with the positive polarity of the preceding intra-cloud discharges suggests that the jets originate from upward propagating negative leaders initiated inside the thundercloud. All events propagate upward from the top of the cloud nearly vertically except for one event that develops in a slanted direction, about twenty three degrees from the vertical. With only a few branches, the three blue jet/starter events display a structure very similar to a cloud-to-ground lightning stroke. Our observations support the unified view of the upward discharges from thunderclouds advanced by Krehbiel et al. [2008] and Riousset et al. [2010]. In this talk, we discuss the video observations of the events and the associated radio signatures in detail.

  8. 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 Image of SS 433: Red-and-Blue Line Shows Path of Constant-Speed Jets. Note Poor Match of Path to Image. CREDIT: Blundell & Bowler, NRAO/AUI/NSF SS 433 Same Image, With Colored Beads Representing Particle Ejections at Different Speeds. Particle Path Now Matches. CREDIT: Blundell & Bowler, NRAO/AUI/NSF Click Here for Page of Full-Sized Graphics The new VLA image shows two full turns of the jets' corkscrew on both sides of the core. Analyzing the image showed that if material came from the core at a constant speed, the jet paths would not accurately match the details of the image. "By simulating ejections at varying speeds, we were able to produce an exact match to the observed structure," Blundell explained. The scientists first did their match to one of the jets. "We then were stunned to see that the varying speeds that matched the structure of one jet also exactly reproduced the other jet's path," Blundell said. Matching the speeds in the two jets reproduced the observed structure even allowing for the fact that, because one jet is moving more nearly away from us than the other, it takes light longer to reach us from it, she added. The astrophysicists speculate that the changes in ejection speed may be caused by changes in the rate at which material is transferred from the companion star onto the accretion disk. The detailed new VLA image also allowed the astrophysicists to determine that SS 433 is nearly 18,000 light-years distant from Earth. Earlier estimates had the object, in the constellation Aquila, as near as 10,000 light-years. An accurate distance, the scientists said, now allows them to better determine the age of the shell of debris blown out by the supernova explosion that created the dense, compact object in the microquasar. Knowing the distance accurately also allows them to measure the actual brightness of the microquasar's components, and this, they said, improves their understanding of the physical processes at work in the system. The breakthrough image was made using 10 hours of observing time with the VLA in a configuration that maximizes the VLA's ability to see fine detail. It represents the longest "time exposure" of SS 433 at radio wavelengths, and thus shows the faintest details. It also represents the best such image that can be done with current technology. Because the jets in SS 433 are moving, their image would be "smeared" in a longer observation. In order to see even fainter details in the jets, the astrophysicists must await the greater sensitivity of the Expanded VLA, set to become available in a few years. SS 433 was the first example of what now are termed microquasars, binary systems with either a neutron star or black hole orbited by another star, and emitting jets of material at high speeds. The strange stellar system received a wealth of media coverage in the late 1970s and early 1980s. A 1981 Sky & Telescope article was entitled, "SS 433 -- Enigma of the Century." Because microquasars in our own Milky Way Galaxy are thought to produce their high-speed jets of material through processes similar to those that produce jets from the cores of galaxies, the nearby microquasars serve as a convenient "laboratory" for studying the physics of jets. The microquasars are closer and show changes more quickly than their larger cousins. Katherine Blundell is a University Research Fellow funded by the UK's Royal Society. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

  9. 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

  10. 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

  11. 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.

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

    PubMed

    Lamsdell, James C; Braddy, Simon J

    2010-04-23

    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

  13. 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

  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 magnaPasteuria ramosa hostparasite 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. The triangulation of the gigantic jets observed by the optical observation network in Taiwan

    NASA Astrophysics Data System (ADS)

    Chen, Alfred B.; Huang, Chien-Fong; Peng, Kang-Ming; Su, Han-Tzong; Hsu, Rue-Ron

    2015-04-01

    The optical triangulation of sprites and elves by the multiple sites has been done in the past decades, but the similar observation on gigantic jets has never been reported yet. A ground optical observation network consisting of four stations at Kimen, Penghu, Tainan, and Taitung (from west to east) has been established in Taiwan since 2012. Each station equipped with two sets of Watec low-light sensitivity cameras, and the elevation and azimuth of the observation can be fully remote controlled to point toward the on-going convection system in the vicinity of Taiwan. In summer 2014, more than 6 gigantic jets were captured by at least two stations successfully. The triangulation and ULF sferics of these interesting events provides an excellent chance to explore the spatial and temporal evolution of the jets in different phases. In this presentation, this ground observation network will be introduced, the detail evolution of the recorded gigantic jets is presented. The preliminary result implies that the jets may not pop from the cloudtop straightforwardly, and some twists occur during the propagation of the jets. A more complicated analysis of the tomography for the advanced triangulation will be mentioned, too.

  16. Clinical and genetic characterization of pituitary gigantism: an international collaborative study in 208 patients.

    PubMed

    Rostomyan, Liliya; Daly, Adrian F; Petrossians, Patrick; Nachev, Emil; Lila, Anurag R; Lecoq, Anne-Lise; Lecumberri, Beatriz; Trivellin, Giampaolo; Salvatori, Roberto; Moraitis, Andreas G; Holdaway, Ian; Kranenburg-van Klaveren, Dianne J; Chiara Zatelli, Maria; Palacios, Nuria; Nozieres, Cecile; Zacharin, Margaret; Ebeling, Tapani; Ojaniemi, Marja; Rozhinskaya, Liudmila; Verrua, Elisa; Jaffrain-Rea, Marie-Lise; Filipponi, Silvia; Gusakova, Daria; Pronin, Vyacheslav; Bertherat, Jerome; Belaya, Zhanna; Ilovayskaya, Irena; Sahnoun-Fathallah, Mona; Sievers, Caroline; Stalla, Gunter K; Castermans, Emilie; Caberg, Jean-Hubert; Sorkina, Ekaterina; Auriemma, Renata Simona; Mittal, Sachin; Kareva, Maria; Lysy, Philippe A; Emy, Philippe; De Menis, Ernesto; Choong, Catherine S; Mantovani, Giovanna; Bours, Vincent; De Herder, Wouter; Brue, Thierry; Barlier, Anne; Neggers, Sebastian J C M M; Zacharieva, Sabina; Chanson, Philippe; Shah, Nalini Samir; Stratakis, Constantine A; Naves, Luciana A; Beckers, Albert

    2015-10-01

    Despite being a classical growth disorder, pituitary gigantism has not been studied previously in a standardized way. We performed a retrospective, multicenter, international study to characterize a large series of pituitary gigantism patients. We included 208 patients (163 males; 78.4%) with growth hormone excess and a current/previous abnormal growth velocity for age or final height >2 s.d. above country normal means. The median onset of rapid growth was 13 years and occurred significantly earlier in females than in males; pituitary adenomas were diagnosed earlier in females than males (15.8 vs 21.5 years respectively). Adenomas were ≥10 mm (i.e., macroadenomas) in 84%, of which extrasellar extension occurred in 77% and invasion in 54%. GH/IGF1 control was achieved in 39% during long-term follow-up. Final height was greater in younger onset patients, with larger tumors and higher GH levels. Later disease control was associated with a greater difference from mid-parental height (r=0.23, P=0.02). AIP mutations occurred in 29%; microduplication at Xq26.3 - X-linked acrogigantism (X-LAG) - occurred in two familial isolated pituitary adenoma kindreds and in ten sporadic patients. Tumor size was not different in X-LAG, AIP mutated and genetically negative patient groups. AIP-mutated and X-LAG patients were significantly younger at onset and diagnosis, but disease control was worse in genetically negative cases. Pituitary gigantism patients are characterized by male predominance and large tumors that are difficult to control. Treatment delay increases final height and symptom burden. AIP mutations and X-LAG explain many cases, but no genetic etiology is seen in >50% of cases. PMID:26187128

  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. Velocidades radiales de estrellas gigantes rojas y blue stragglers en cúmulos abiertos

    NASA Astrophysics Data System (ADS)

    González, J. F.; Lapasset, E.

    Se presentan mediciones de las estrellas más brillantes en los campos de los cúmulos abiertos NGC 6530, NGC 2516, NGC 3114, Cr 223 y NGC 2437. Mediante correlaciones cruzadas se obtiene la velocidad de unas 25 gigantes rojas con el objeto de derivar la velocidad media de cada asociación. En base a los espectros obtenidos de los blue stragglers se discuten sus principales características y su probabilidad de pertenencia. Finalmente, se presentan las observaciones para cinco nuevas binarias espectroscópicas detectadas.

  19. 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.

  20. GaAs-oxide interface states - Gigantic photoionization via Auger-like process

    NASA Technical Reports Server (NTRS)

    Lagowski, J.; Kazior, T. E.; Gatos, H. C.; Walukiewicz, W.; Siejka, J.

    1981-01-01

    Spectral and transient responses of photostimulated current in MOS structures were employed for the study of GaAs-anodic oxide interface states. Discrete deep traps at 0.7 and 0.85 eV below the conduction band were found with concentrations of 5 x 10 to the 12th/sq cm and 7 x 10 to the 11th/sq cm, respectively. These traps coincide with interface states induced on clean GaAs surfaces by oxygen and/or metal adatoms (submonolayer coverage). In contrast to surfaces with low oxygen coverage, the GaAs-thick oxide interfaces exhibited a high density (about 10 to the 14th/sq cm) of shallow donors and acceptors. Photoexcitation of these donor-acceptor pairs led to a gigantic photoionization of deep interface states with rates 1000 times greater than direct transitions into the conduction band. The gigantic photoionization is explained on the basis of energy transfer from excited donor-acceptor pairs to deep states.

  1. 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.

  2. 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.

  3. 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

  4. [What can the physician do when faced with the gigantic puzzle of abuse?].

    PubMed

    Gauthier, Cornelia

    2009-01-01

    The entire subject of abuse can be compared to a gigantic puzzle were patients as well as their physicians get lost. The goal of this article is first to find a common definition to all acts of abuse and then to subdivide them into three distinct categories: sexual, physical, and emotional abuse. The treating physician should realize that victims of abuse, after the passage of time, will eventually fall sick and consult a doctor for physical or/and psychological symptoms which are the result of the past abuse. Most of the time, these patients will not speak spontaneously of the abuse, either because they have not understood the cause/effect relation, or because the abuse feels unspeakable. It is therefore necessary for the doctor to know how to detect abuse through symptomatology, how to help these patients reveal their secret, how to listen with a non-judgemental ear, and how to propose appropriate treatment. PMID:19999625

  5. 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.

  6. Gigantic aneurysm of a venous bypass graft causing superior vena cava syndrome

    PubMed Central

    Bugajski, Pawe?; K?sinowski, Ryszard; Furmaniuk, Jaromir; Rze?niczak, Janusz; Poprawka, Tomasz; Jedli?ski, Ireneusz; Greberski, Krzysztof; Kalawski, Ryszard

    2014-01-01

    A case of a 66-year-old patient 13 years after coronary artery bypass grafting (CABG) admitted to hospital with typical ischemic chest pain and symptoms of superior vena cava syndrome (SVCS) is described. Non-invasive diagnostics confirmed acute coronary syndrome: non-ST-elevated myocardial infarction (ACS NSTEMI). Trans-thoracic echocardiography (TTE) revealed a gigantic tumor mass modeling the right atrium, causing chronic cardiac tamponade. Angiography showed that the tumor mass was in fact the aneurysmatically changed venous bypass graft to the right coronary artery (RCA). Computed tomography angiography (CT-angio) confirmed venous aneurysm size (the longest diameters were 10.2 cm 8.7 cm). We also present treatment planning and the aneurysmal surgical removal procedure of this very rare case. PMID:26336399

  7. 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.

  8. 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

  9. 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

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

    PubMed Central

    Brunet-LLobet, Llus; 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. GaAs-oxide interface states - A gigantic photoionization effect and its implications to the origin of these states

    NASA Technical Reports Server (NTRS)

    Lagowski, J.; Walukiewicz, W.; Kazior, T. E.; Gatos, H. C.; Siejka, J.

    1981-01-01

    Gigantic photoionization was discovered on GaAs-oxide interfaces leading to the discharge of deep surface states with rates exceeding 1000 times those of photoionization transitions to the conduction band. It exhibits a peak similar to acceptor-donor transitions and is explained as due to energy transfer from photo-excited donor-acceptor pairs to deep surface states. This new process indicates the presence of significant concentrations of shallow donor and acceptor levels not recognized in previous interface models.

  12. 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.

  13. 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 Nagy D., Papp G., Benedek J., The gravitational potential and its derivatives for the prism, Journal of Geodesy, 74 (7-8), pp. 552-560, 2000 Turner D. A., Anderson I. J., Mason J. C., Cox M. G., An algorithm for fitting an ellipsoid to data, CiteseerXBeta, http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.36.2773 , 1999

  14. Commissioning of the gigantic anaerobic sludge digesters at the wastewater treatment plant of Athens.

    PubMed

    Gikas, P

    2008-02-01

    The pre-commissioning strategy, the start-up procedure and the analytical data obtained during the commissioning period for the first of the four new anaerobic gigantic digesters, with active volume of 10,000 m3 each, are presented in this paper. The digester was initially filled up with water, and the temperature was raised to 36 +/- 1 degrees C. Then, a total amount of 1,860 m3 of digested primary sludge was transferred, in four equal daily batches, into the digester from neighbouring digesters, performing routine operation. Following this, the digester was gradually fed with fresh primary thickened sludge, up to the point that the retention time reached approximately 20 d. A number of significant operational parameters (pH, alkalinity, total and volatile solids concentration, volatile fatty acids concentration, biogas production rate and composition) were monitored several times per day, and the appropriate adjustments were performed in order to achieve stable operation. The time duration of the whole process was about two and a half months. Later on, the digester was supplied with a mixture of primary and biological sludge. PMID:18613612

  15. 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

  16. Respiratory evolution facilitated the origin of pterosaur flight and aerial gigantism.

    PubMed

    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

  17. 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.

  18. 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

  19. 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

  20. 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.

  1. 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.

  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. 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 enhance the value of observation time.;

  4. Increase in tracheal investment with beetle size supports hypothesis of oxygen limitation on insect gigantism

    PubMed Central

    Kaiser, Alexander; Klok, C. Jaco; Socha, John J.; Lee, Wah-Keat; Quinlan, Michael C.; Harrison, Jon F.

    2007-01-01

    Recent studies have suggested that Paleozoic hyperoxia enabled animal gigantism, and the subsequent hypoxia drove a reduction in animal size. This evolutionary hypothesis depends on the argument that gas exchange in many invertebrates and skin-breathing vertebrates becomes compromised at large sizes because of distance effects on diffusion. In contrast to vertebrates, which use respiratory and circulatory systems in series, gas exchange in insects is almost exclusively determined by the tracheal system, providing a particularly suitable model to investigate possible limitations of oxygen delivery on size. In this study, we used synchrotron x-ray phase–contrast imaging to visualize the tracheal system and quantify its dimensions in four species of darkling beetles varying in mass by 3 orders of magnitude. We document that, in striking contrast to the pattern observed in vertebrates, larger insects devote a greater fraction of their body to the respiratory system, as tracheal volume scaled with mass1.29. The trend is greatest in the legs; the cross-sectional area of the trachea penetrating the leg orifice scaled with mass1.02, whereas the cross-sectional area of the leg orifice scaled with mass0.77. These trends suggest the space available for tracheae within the leg may ultimately limit the maximum size of extant beetles. Because the size of the tracheal system can be reduced when oxygen supply is increased, hyperoxia, as occurred during late Carboniferous and early Permian, may have facilitated the evolution of giant insects by allowing limbs to reach larger sizes before the tracheal system became limited by spatial constraints. PMID:17666530

  5. Increase in tracheal investment with beetle size supports hypothesis of oxygen limitation on insect gigantism.

    PubMed

    Kaiser, Alexander; Klok, C Jaco; Socha, John J; Lee, Wah-Keat; Quinlan, Michael C; Harrison, Jon F

    2007-08-01

    Recent studies have suggested that Paleozoic hyperoxia enabled animal gigantism, and the subsequent hypoxia drove a reduction in animal size. This evolutionary hypothesis depends on the argument that gas exchange in many invertebrates and skin-breathing vertebrates becomes compromised at large sizes because of distance effects on diffusion. In contrast to vertebrates, which use respiratory and circulatory systems in series, gas exchange in insects is almost exclusively determined by the tracheal system, providing a particularly suitable model to investigate possible limitations of oxygen delivery on size. In this study, we used synchrotron x-ray phase-contrast imaging to visualize the tracheal system and quantify its dimensions in four species of darkling beetles varying in mass by 3 orders of magnitude. We document that, in striking contrast to the pattern observed in vertebrates, larger insects devote a greater fraction of their body to the respiratory system, as tracheal volume scaled with mass1.29. The trend is greatest in the legs; the cross-sectional area of the trachea penetrating the leg orifice scaled with mass1.02, whereas the cross-sectional area of the leg orifice scaled with mass0.77. These trends suggest the space available for tracheae within the leg may ultimately limit the maximum size of extant beetles. Because the size of the tracheal system can be reduced when oxygen supply is increased, hyperoxia, as occurred during late Carboniferous and early Permian, may have facilitated the evolution of giant insects by allowing limbs to reach larger sizes before the tracheal system became limited by spatial constraints. PMID:17666530

  6. Multi-Instrumental Observations of a Gigantic Jet Produced by a Winter Thunderstorm in Europe

    NASA Astrophysics Data System (ADS)

    van der Velde, Oscar; Arnone, Enrico; Zanotti, Ferruccio

    2010-05-01

    At 23:36:56 UTC on 12 December 2009, a Gigantic Jet (GJ) was recorded by a member of the Italian Meteor and TLE Network. 51 additional transient luminous events including sprites, elves, halos and two cases of upward lightning were observed that night. Analysis of the imagery and detected lightning near the time of the GJ revealed its most likely location to be near 41.99°N and 7.61°E, 93 km west of Ajaccio, Corsica, leading to a top altitude near 92 km and a "trailing jet" phenomenon between 37-59 km, matching with earlier reported GJs. A sprite with halo occurred during the trailing jet phase of the GJ, which was triggered by a detected positive cloud-to-ground lightning (+CG) flash of 198 kA. The sprite initiated at lower than typical altitudes, with a hole at the location of the GJ. At the same time, the trailing jet and beads were re-illuminated. Four minutes after the event, an extraordinary 406 kA +CG producing a bright elve and sprite was detected near the same location. The location of the GJ corresponded exactly to a distinct cloud top (-34°C). This is the first documented GJ which emerged from a winter thunderstorm of only 6 km tall, which shows that high cloud tops are not required for initiation of GJs. With strong vertical wind shear, the meteorological situation was different from typical outbreaks of fall and winter thunderstorms in the Mediterranean. Electromagnetic waveforms from Hungary, Poland, and Durham (North Carolina, USA), reveal unusually large ELF/VLF signals (in contrast to several previous GJ events) and Schumann resonances persisting for 3.5 seconds. A synthesis of this and any additional data will be presented in detail at the conference.

  7. 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.

  8. Climatic control on the growth of gigantic gypsum crystals within hypogenic caves (Naica mine, Mexico)?

    NASA Astrophysics Data System (ADS)

    Garofalo, Paolo S.; Fricker, Mattias B.; Günther, Detlef; Forti, Paolo; Mercuri, Anna-Maria; Loreti, Mara; Capaccioni, Bruno

    2010-01-01

    Three hypogenic caves within the Naica mine of Mexico ( Cueva de los Cristales — CLC, Ojo de la Reina — OR, and Cueva de las Velas — CLV) host spectacular gypsum crystals up to 11 m in length. These caves are close to another shallow cave of the area ( Cueva de las Espadas — CLE), with which they cover a 160 m-deep vertical section of the local drainage basin. Similar to other hypogenic caves, all these caves lack a direct connection with the land surface and should be unrelated with climate. A record of multi-technique fluid inclusion data and pollen spectra from cave and mine gypsum indicates surprisingly that climatic changes occurring at Naica could have controlled fluid composition in these caves, and hence crystal growth. Microthermometry and LA-ICP-Mass Spectrometry of fluid inclusions indicate that the shallow, chemically peculiar, saline fluid (up to 7.7 eq. wt.%NaCl) of CLE could have formed from evaporation, during a dry and hot climatic period. The fluid of the deep caves was instead of low salinity (˜ 3.5 eq. wt.% NaCl) and chemically homogeneous, and was poorly affected by evaporation. We propose that mixing of these two fluids, generated at different depths of the Naica drainage basin, determined the stable supersaturation conditions for the gigantic gypsum crystals to grow. Fluid mixing was controlled by the hydraulic communication between CLE and the other deep caves, and must have taken place during cycles of warm-dry and fresh-wet climatic periods, which are known to have occurred in the region. Pollen grains from a 35 ka-old gypsum crystal of CLC corresponds to a fairly homogenous catchment basin made of a mixed broadleaf wet forest, which suggests precipitation during a fresh-wet climatic period and confirms our interpretation of the fluid inclusion data. The unusual combination of geological and geochemical factors of Naica suggests that other hypogenic caves found elsewhere may not host similar crystals. However, this work shows that fluid inclusions and pollen spectra represent a useful tool for cave studies in general, and if used in future studies might be essential to unravel the mechanisms of hypogenic deposition.

  9. 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 history long before has not been clarified. We sampled plant fragments from the deposits in a depression at the head of a landslide along a linear depression. They were dated by using C-14, of which results suggest that major movement of landslides and possibly lateral spreading might occurred 3100, 2600, and 2200 BC, which may correspond to the occurrence of large earthquake. The lateral spreading may have occurred intermittently and destabilized their side slopes, which could have slid during earthquakes and rainstorms.

  10. 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 deposits. Here are presented a new data on: parameters, extent and probable source for Lenin rock avalanche, travelled 24 km from the back wall of the Lenin Glacier over the glacial Achiktash hummock deposit covering more than 35 km2; updated data on Koman rock avalanche deposit, such as its extend and source; the first reconstruction of the Achiktash glacial material deposition with proposed landscape evolution during recent Quaternary in respect to the large landslide in the catchment. Hewitt, K., 1999. Quaternary moraines vs. catastrophic rock avalanches in the Karakoram Himalaya, Northern Pakistan. Quaternary Research, v. 51, p. 220-237. Reznichenko, N.V., Davies, T.R.H., Shulmeister, J. and Larsen S.H, 2012. A new technique for identifying rock-avalanche-sourced sediment in moraines and some paleoclimatic implications. Geology, v. 40, p. 319-322.

  11. Paleostress analysis of a gigantic gravitational mass movement in active tectonic setting: The Qoshadagh slope failure, Ahar, NW Iran

    NASA Astrophysics Data System (ADS)

    Baroň, I.; Kernstocková, M.; Faridi, M.; Bubík, M.; Milovský, R.; Melichar, R.; Sabouri, J.; Babůrek, J.

    2013-10-01

    For better understanding of the dynamics of large slope failures, the slope-scale stress field reconstructions are eligible. A new approach of paleostress analysis of large gravitational mass movements, based on the multiple inverse method in 9D space and processed by a non-commercial code MARK2010, is demonstrated on the case of a gigantic gravitational slope failure in active tectonic setting at Mount Qoshadagh in NW Iran. The entire slope failure represents a very deep-seated gravitational slope deformation with relatively short displacement, roto-translational base and an estimated volume of about 83-110 km3 which is of the last glacial age. This gigantic slope failure has developed in an active-tectonic setting along the Qoshadagh Fault System (or called South Ahar Fault), which caused fast uplift of the entire mountain range of Qoshadagh, and it was probably seismically triggered. Using this paleostress approach, we were able to distinguish the mass-movement stress phase of NW compression in the rockslide's zone of compression and NW-SE extension in the upper part from a variety of other 8 regional-tectonic and 2 subsequent gravitational phases. Maximum principal stress of the slope-failure phase was in its compression zone sub-parallel to the estimated displacement vector; in the head it was sub-vertical. The paleostress analysis has been proved as a useful tool for reconstructing the stress field evolution of large slope failures.

  12. 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.

  13. Aggressive tumor growth and clinical evolution in a patient with X-linked acro-gigantism syndrome.

    PubMed

    Naves, Luciana A; Daly, Adrian F; Dias, Luiz Augusto; Yuan, Bo; Zakir, Juliano Coelho Oliveira; Barra, Gustavo Barcellos; Palmeira, Leonor; Villa, Chiara; Trivellin, Giampaolo; Júnior, Armindo Jreige; Neto, Florêncio Figueiredo Cavalcante; Liu, Pengfei; Pellegata, Natalia S; Stratakis, Constantine A; Lupski, James R; Beckers, Albert

    2016-02-01

    X-linked acro-gigantism (X-LAG) syndrome is a newly described disease caused by microduplications on chromosome Xq26.3 leading to copy number gain of GPR101. We describe the clinical progress of a sporadic male X-LAG syndrome patient with an Xq26.3 microduplication, highlighting the aggressive natural history of pituitary tumor growth in the absence of treatment. The patient first presented elsewhere aged 5 years 8 months with a history of excessive growth for >2 years. His height was 163 cm, his weight was 36 kg, and he had markedly elevated GH and IGF-1. MRI showed a non-invasive sellar mass measuring 32.5 × 23.9 × 29.1 mm. Treatment was declined and the family was lost to follow-up. At the age of 10 years and 7 months, he presented again with headaches, seizures, and visual disturbance. His height had increased to 197 cm. MRI showed an invasive mass measuring 56.2 × 58.1 × 45.0 mm, with compression of optic chiasma, bilateral cavernous sinus invasion, and hydrocephalus. His thyrotrope, corticotrope, and gonadotrope axes were deficient. Surgery, somatostatin analogs, and cabergoline did not control vertical growth and pegvisomant was added, although vertical growth continues (currently 207 cm at 11 years 7 months of age). X-LAG syndrome is a new genomic disorder in which early-onset pituitary tumorigenesis can lead to marked overgrowth and gigantism. This case illustrates the aggressive nature of tumor evolution and the challenging clinical management in X-LAG syndrome. PMID:26607152

  14. 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

    The Paleocene-Eocene Thermal Maximum (PETM) is one of the most severe climatic events of the Cenozoic Era. A massive injection of light carbon into the oceans and atmosphere over a few thousand of years triggered drastic perturbation of Earth's climate resulting in abrupt global warming of ~5-9oC [Sluijs et al., 2007] that persisted for ~180,000 years. This episode is marked by the diversification and radiation of terrestrial plants and mammals while in the marine realm numerous deep-sea benthic foraminifera species disappeared and new forms evolved. Sediments deposited during the PETM are clay-rich and contain distinct evidence of these climatic changes. Kopp et al., (2007) and Lippert & Zachos (2007) report an extraordinary magnetofossil ‘Lagerstätte' in lowermost Eocene kaolinite-rich clay sediments deposited at subtropical paleolatitude in the Atlantic Coastal Plain of New Jersey, USA. Magnetofossils are magnetic particles produced most abundantly by magnetotactic bacteria. Kopp et al. (2007) and Lippert & Zachos (2007) used ferromagnetic resonance (FMR) spectroscopy, other rock magnetic methods, and transmission electron microscopy (TEM) of magnetic separates to characterize sediments from boreholes at Ancora (ODP Leg 174AX) and Wilson Lake, NJ, respectively. These sediments contain abundant ~40- to 300-nm cuboidal, elongate-prismatic and bullet-shaped magnetofossils, sometimes arranged in short chains, resembling crystals in living magnetotactic bacteria. Despite the scarcity of intact magnetofossil chains, the asymmetry ratios of the FMR spectra reflects a profusion of elongate single domain (SD) crystals and/or chains. Here we address both conundrums by reporting the discovery from these same sediments of exceptionally large and novel biogenic magnetite crystals unlike any previously reported from living organisms or from sediments. Aside from abundant bacterial magnetofossils, electron microscopy reveals novel spearhead-like and spindle-like magnetite crystals up to 4 μm long (eight times larger than magnetite produced by magnetotactic bacteria) and elongated hexaoctahedra up to 1.4 μm long. Similar to magnetite produced by magnetotactic bacteria, these single-crystal particles exhibit chemical composition and lattice perfection consistent with a biogenic origin. The oxygen isotopic composition of indiviual particles supports a low temperature aquatic origin. Electron holography indicates single-domain magnetization despite the large crystal size. In a few cases, we observed apparently intact, tip-outward spherical assemblages of spearhead-like particles that possibly represent the preserved original biological arrangement of these crystals in a hitherto unknown magnetite producing organism. The discovery of these exceptionally large biogenic magnetite crystals that possibly represent the remains of a new microorganism that appeared and disappeared with the PETM sheds some light upon the ecological response to biogeochemical changes that occurred during this warming event. The abundance of fossil magnetotactic bacteria on the Atlantic Coastal Plain during the PETM could be explained by enhanced production, enhanced preservation, or both. The presence of novel magnetofossils, however, argues that changes in growth conditions are a major part of the explanation. Considering that other bacterial magnetofossils are present (although less abundant) and well-preserved in sediments below and above the PETM clay, as well as in a sand lens within the PETM clay [Kopp et al., 2007], suggests that the new magnetofossils are unlikely to be a preservation artefact. We conclude, therefore, 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 - resulted in diversification of magnetite-forming organisms, likely including eukaryotes. In this study we extended the search for these new magnetofossils [Schumann 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.

  15. 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.

  16. 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

  17. Gigantic enhancement in the dielectric properties of polymer-based composites using core/shell MWCNT/amorphous carbon nanohybrids

    NASA Astrophysics Data System (ADS)

    Guo, Qikai; Xue, Qingzhong; Sun, Jin; Dong, Mingdong; Xia, Fujun; Zhang, Zhongyang

    2015-02-01

    Novel core/shell structured multi-walled carbon nanotube/amorphous carbon (MWCNT@AC) nanohybrids were successfully prepared using a simple and novel method. Subsequently, the MWCNT@AC nanohybrids were used as fillers to enhance the dielectric properties of poly(vinylidene fluoride) (PVDF) based composites. It is found that the dielectric constant of the MWCNT@AC/PVDF composites can reach 5910 (the dielectric loss is ~2), which is considerably better than that of MWCNT/PVDF composites. The uniform amorphous carbon shell provides an insulative layer between adjacent MWCNTs in the polymer matrix, which not only prevents the direct contact of MWCNTs but also improves the dispersibility of the MWCNTs. Therefore, a surprising number of microcapacitors could be formed in the composites before the formation of a conductive network, leading to a gigantic enhancement in the dielectric properties. Our strategy provides a new approach to fabricate excellent dielectric materials for energy storage capacitors. In addition, the design concept used in this work can be extended to other carbon materials.

  18. 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

  19. Gigantic enhancement in the dielectric properties of polymer-based composites using core/shell MWCNT/amorphous carbon nanohybrids.

    PubMed

    Guo, Qikai; Xue, Qingzhong; Sun, Jin; Dong, Mingdong; Xia, Fujun; Zhang, Zhongyang

    2015-02-28

    Novel core/shell structured multi-walled carbon nanotube/amorphous carbon (MWCNT@AC) nanohybrids were successfully prepared using a simple and novel method. Subsequently, the MWCNT@AC nanohybrids were used as fillers to enhance the dielectric properties of poly(vinylidene fluoride) (PVDF) based composites. It is found that the dielectric constant of the MWCNT@AC/PVDF composites can reach 5910 (the dielectric loss is ∼2), which is considerably better than that of MWCNT/PVDF composites. The uniform amorphous carbon shell provides an insulative layer between adjacent MWCNTs in the polymer matrix, which not only prevents the direct contact of MWCNTs but also improves the dispersibility of the MWCNTs. Therefore, a surprising number of microcapacitors could be formed in the composites before the formation of a conductive network, leading to a gigantic enhancement in the dielectric properties. Our strategy provides a new approach to fabricate excellent dielectric materials for energy storage capacitors. In addition, the design concept used in this work can be extended to other carbon materials. PMID:25640081

  20. 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

  1. 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

  2. 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

  3. What Lies Beneath: Sub-Articular Long Bone Shape Scaling in Eutherian Mammals and Saurischian Dinosaurs Suggests Different Locomotor Adaptations for Gigantism

    PubMed Central

    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

  4. Reduced predator species richness drives the body gigantism of a frog species on the Zhoushan Archipelago in China.

    PubMed

    Li, Yiming; Xu, Feng; Guo, Zhongwei; Liu, Xuan; Jin, Changnan; Wang, Yanping; Wang, Supen

    2011-01-01

    1. Shifts in the body size of insular vertebrates have been an interesting theme in ecological and evolutionary studies. Four primary factors, including predation pressures, resource availability, inter-species competition and immigrant selection, have been proposed to explain the trend in insular body size. Life-history theory predicts that body size, average age, the proportion of old-aged members and the density of insular populations are negatively correlated with predator species richness, and that body size and population density are positively related to resource availability. The niche expansion hypothesis argues that a positive relationship is expected to exist between insular body size and prey size, which varies in response to extinction due to small or large competitors. The immigrant hypothesis predicts that insular body size is positively correlated with distance to the mainland. 2. We tested these hypotheses by using populations of rice frogs Rana limnocharis on 20 islands in the Zhoushan Archipelago and two sites of nearby mainland China. 3. The body size (snout-vent length) of rice frogs on half of the islands was larger before and after the variable of age was controlled for; rice frog density and prey availability was higher and prey size was larger on most of the islands as compared to the two mainland sites. On the islands, the body size and other features [e.g. average age, the proportion of old-aged frogs (ages 3 and 4) and density] of the rice frogs were negatively associated with predator species richness; female body size and other features were positively associated with prey availability. The inference of multivariate linear models based on corrected Akaike Information Criterion (AIC(c) ) showed that the relative importance of predator species richness on body size and each of the other features was larger than that of prey availability, prey size and distance to the mainland. In addition, the parameters for predator species richness were all negative. 4. The results provided strong support for the life-history theory of predation pressures, but weak evidence for the life-history theory of prey availability, the niche expansion or the immigrant hypothesis. The reduced predator species richness was a dominant factor contributing to the body gigantism of rice frogs on the islands. PMID:20840555

  5. 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)

  6. 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)

  7. Análise da cinemática interna das regiões HII gigantes e das galáxias HII

    NASA Astrophysics Data System (ADS)

    Plana, H.; Telles, E.; Maíz-Apellániz, J.

    2003-08-01

    Neste trabalho nós mostramos os primeiros resultados de um estudo sobre a cinemática das Regiões HII Gigantes (GHIIRs) em galáxias próximas. Essas regiões HII têm um diâmetro médio entre 100 pc e 1000 pc e uma taxa de formação estelar de 106 M¤ / ano sendo equivalente à observada em galáxias de tipo tardio correspondendo a uma taxa de formação estelar por unidade de volume uma ordem de magnitude maior que a observada em regiões HII normais. Usando espectros de fenda longas em várias posições, nós construímos mapas de velocidades, de dispersão e de intensidade para várias linhas de emissão como Ha, Hb, [NII]6584 Å, [OIII]5007 Å e o doublet de [SII], para cinco regiões gigantes: NGC 2403 II e IV, NGC 595, NGC 5461, NGC 5471, NGC 5455. O estudo da cinemática (mapas de velocidades e da dispersão) mostrou, por exemplo, a presença de cascas em expansão em NGC 595 ou perfis de emissão com várias componentes em NGC 5461. Os perfis de emissão também mostram velocidades supersônicas. Os resultados são discutidos em comparação com os de estudos anteriores realizados.

  8. Palaeoecology: a gigantic fossil arthropod trackway.

    PubMed

    Whyte, Martin A

    2005-12-01

    A unique, complex trackway has been discovered in Scotland: it was made roughly 330 million years ago by a huge, six-legged water scorpion that was about 1.6 m long and a metre wide. To my knowledge, this is not only the largest terrestrial trackway of a walking arthropod to be found so far, but is also the first record of locomotion on land for a species of Hibbertopterus (Eurypterida). This evidence of lumbering movement indicates that these giant arthropods, now extinct, could survive out of water at a time when the earliest tetrapods were making their transition to the land. PMID:16319874

  9. 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.

  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. Gigantic macroautophagy in programmed nuclear death of Tetrahymena thermophila.

    PubMed

    Akematsu, Takahiko; Pearlman, Ronald E; Endoh, Hiroshi

    2010-10-01

    Programmed nuclear death (PND) in Tetrahymena is a unique process during conjugation, in which only the parental macronucleus is degraded and then eliminated from the progeny cytoplasm, but other co-existing nuclei such as new micro- and macronuclei are unaffected. PND through autophagic elimination is expected to be strictly controlled, considering the significant roles in ciliates such as turnover of disused organelles and production of the next generation. Here we demonstrate that PND in Tetrahymena involves peculiar aspects of autophagy, which differ from mammalian or yeast macroautophagy. Drastic change of the parental macronucleus occurs when differentiation of new macronuclei is initiated. Combined use of monodansylcadaverine and a lysosome indicator LysoTracker Red showed that prior to nuclear condensation, the envelope of the parental macronucleus changed its nature as if it is an autophagic membrane, without the accumulation of a pre-autophagosomal structure from the cytoplasm. Subsequently, lysosomes approached only to the parental macronucleus and localized at the envelope until a final resorption stage. In addition, we found that the parental macronucleus exhibits certain sugars and phosphatidylserine on the envelope, which are possible "attack me" signals, that are not found on other types of nuclei. These findings suggest that PND is a highly elaborated process, different from the typical macroautophagy seen in other systems, and is executed through interaction between specific molecular signals on the parental macronuclear envelope and autophagic/lysosomal machineries. PMID:20798592

  12. A gigantic bird from the Upper Cretaceous of Central Asia

    PubMed Central

    Naish, Darren; Dyke, Gareth; Cau, Andrea; Escuillié, François; Godefroit, Pascal

    2012-01-01

    We describe an enormous Late Cretaceous fossil bird from Kazakhstan, known from a pair of edentulous mandibular rami (greater than 275 mm long), which adds significantly to our knowledge of Mesozoic avian morphological and ecological diversity. A suite of autapomorphies lead us to recognize the specimen as a new taxon. Phylogenetic analysis resolves this giant bird deep within Aves as a basal member of Ornithuromorpha. This Kazakh fossil demonstrates that large body size evolved at least once outside modern birds (Neornithes) and reveals hitherto unexpected trophic diversity within Cretaceous Aves. PMID:21835881

  13. Gigantic SO2 emission from Miyakejima volcano, Japan, caused by caldera collapse

    NASA Astrophysics Data System (ADS)

    Kazahaya, Kohei; Shinohara, Hiroshi; Uto, Kozo; Odai, Masanobu; Nakahori, Yasuhiro; Mori, Hirokazu; Iino, Hideki; Miyashita, Makoto; Hirabayashi, Junichi

    2004-05-01

    An extremely large amount of volcanic gas has been released since mid-August 2000 from the volcanic island of Miyakejima, Japan, after formation of a summit caldera of 1.6 km diameter. The volcanic gas emission was continuous with very little extrusive magma activity. Variation of the SO2 emission rate was monitored by repeated measurements with an airborne correlation spectrometer. In December 2000, the SO2 emission rate averaged for the month peaked at 54 kt/d, which is twice the global SO2 emission rate from nonerupting volcanoes evaluated before this activity. The SO2 emission rate gradually decreased, almost linearly when plotted on a log scale, to 7 kt/d by the end of 2002, and then remained constant until at least December 2003. The total SO2 emission amounts to 18 Mt, comparable to the emission of a large explosive eruption such as Pinatubo in 1991. A theoretical evaluation, based on the model of magma convection in a conduit, suggests that extremely large volcanic gas emissions can be caused by formation of a magma pathway with a slightly larger diameter than exists in common systems, because the magma-transport rate is proportional to the fourth power of the conduit radius. Because volcanic gas emissions were initiated by formation of a summit collapse caldera of 1.6 km diameter, the creation of a large magma-conduit system through fractures formed during caldera collapse is likely the underlying cause of the extremely large volcanic gas emissions from the volcano.

  14. 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

  15. Gigantic Diamondiferous Eclogite from Udachnaya: Mineralogy and Tomography of this Yakutian Xenolith.

    NASA Astrophysics Data System (ADS)

    Taylor, L. A.; Ketchum, R.; Day, J. M.; Stepanov, A.; Carlson, W.; Liu, Y.; Shatsky, V.

    2005-12-01

    Diamondiferous eclogites are rare unique xenoliths brought to the surface of the Earth by kimberlites. The Udachnaya pipe of Yakutia contains many such unusual xenoliths, largely because of the freshness of this kimberlite; usually only 30-80 gm portions are collected during the crushing and production process. However, a giant 8.8 kg relatively fresh diamondiferous eclogite was recently recovered from the ore stockpile. There appear to be two, possibly more, different types of eclogites in this one xenolith, one with Group A garnets, the other with Group B. Three-dimensional, high-resolution computed X-ray tomography (HRCXT) of this diamondiferous eclogite, difficult for its size, has successfully imaged the multitude of diamonds (micro up to 2-3 cts) and their textural relationships with co-existing minerals. This is an extension to the tomography and xenolith dissections performed previously on diamondiferous eclogites by our group (e.g., Taylor et al., 2000, Int'l Geol Rev 42; Anand et al., 2004, Lithos 77). Spatial relationships between diamonds and their surroundings provide clues to the processes that control diamond crystallization. These relationships can be determined by rotating and viewing the 3-D model at different perspectives and orientations to look for specific associations/alignments. The maps obtained from this tomography also form the basis for the delicate dissection of the xenolith, revealing the diamonds as they formed in their mantle host rock. A previous eclogite of 65 g contained 74 macro-diamonds. Inspection of the surface of this 8.8 kg eclogite and examination of the tomographic images indicates that >100 diamonds exist in this eclogite. The diamonds appear to be preferentially located in zones with a prominent sub-planar fabric of secondary mineralization - i.e., zones of increased permeability. Diamond was never observed in direct contact with any fresh, primary minerals. Also, there is insufficient sulfide mineralization to call upon an immiscible-sulfide melt as the diamond-forming medium. The association of the diamonds with secondary minerals is further evidence that the diamonds formed after the initial host eclogite, probably from the introduction of metasomatic carbonate-rich fluids.

  16. 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.

  17. Gigantic swelling of inorganic layered materials: a bridge to molecularly thin two-dimensional nanosheets.

    PubMed

    Geng, Fengxia; Ma, Renzhi; Ebina, Yasuo; Yamauchi, Yusuke; Miyamoto, Nobuyoshi; Sasaki, Takayoshi

    2014-04-01

    Platy microcrystals of a typical layered material, protonated titanate, have been shown to undergo an enormous degree of swelling in aqueous solutions of various amines, including tertiary amines, quaternary ammonium hydroxides, and primary amines. Introducing these solutions expanded the crystal gallery height by up to ~100-fold. Through systematic analysis, we determined that ammonium ion intercalation is predominantly affected by the acid-base equilibrium and that the degree of swelling or inflow of H2O is controlled by the osmotic pressure balance between the gallery and the solution environment, both of which are relatively independent of electrolyte identity but substantially dependent on molarity. In solutions of tertiary amines and quaternary ammonium hydroxides, the uptake of ammonium ions increases nearly linearly with increasing external concentration before reaching a saturation plateau, i.e., ~40% relative to the cation-exchange capacity of the crystals used. The only exception is tetrabutylammonium ions, which yield a lower saturation value, ~30%, owing to steric effects. The swelling behaviors in some primary amine solutions differ as a result of the effect of attractive forces between amine solute molecules on the solution osmotic pressure. Although the swelling is essentially colligative in nature, the stability of the resultant swollen structure is heavily dependent on the chemical nature of the guest ions. Intercalated ions of higher polarity and smaller size help stabilize the swollen structure, whereas ions of lower polarity and larger size lead readily to exfoliation. The insight gained from this study sheds new light on both the incorporation of guest molecules into a gallery of layered structures in general and the exfoliation of materials into elementary single-layer nanosheets. PMID:24635385

  18. 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

  19. 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

  20. 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

  1. 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

  2. Great Earthquakes, Gigantic Landslides, and the Continuing Enigma of the April Fool's Tsunami of 1946

    NASA Astrophysics Data System (ADS)

    Fryer, G. J.; Tryon, M. D.

    2005-12-01

    Paleotsunami studies can extend the record of great earthquakes back into prehistory, but what if the historical record itself is ambiguous? There is growing controversy about whether great earthquakes really occur along the Shumagin and Unimak segments of the Alaska-Aleutian system. The last great tsunami there was April 1, 1946, initiated by an earthquake whose magnitude has variously been reported from 7.1 to 8.5. Okal et al (BSSA, 2003) surveyed the near-field runup and concluded there were two sources: a magnitude 8.5 earthquake, which generated a Pacific-wide tsunami but which produced near-field runups no more than 18 m, and an earthquake-triggered slump whose tsunami reached 42 m at Scotch Cap Light near the western end of Unimak Island, but with runup rapidly decaying eastwards. An M8.5 earthquake, however, is incompatible with GPS strain measurements, which indicate that the maximum earthquake size off Unimak is M7.5. We have long contended that near- and far-field tsunamis were the result of a single earthquake-triggered debris avalanche down the Aleutian slope. In 2004 we were part of an expedition to map and explore the landslide, whose location seemed to be very tightly constrained by the known tsunami travel time to Scotch Cap Light. We found that neither our giant landslide nor Okal et al's smaller slump exist within 100 km of the presumed location. The explanation is obvious in retrospect: the tsunami was so large that it crossed the shallow Aleutian shelf as a bore travelling faster than the theoretical long-wave speed (which we had used to fix the location). Any landslide could only have occurred in an unsurveyed area farther east, off Unimak Bight, the central coast of Unimak Island. That location, however, conflicts with Okal et al's measurements of smaller runup along the Bight. We are now convinced that Okal et al confused the 1946 debris line with the lower line left by the 1957 tsunami. They were apparently unaware that the 1946 tsunami also destroyed an unmanned light on the rocky promontary of Cape Pankof, the eastern tip of Unimak Island. From photographs and pre-1946 charts, we have determined that the 1946 runup at Cape Pankof must have exceeded 25 m, a value that is incompatible with Okal et al's field measurements. We cannot avoid the conclusion that both near-field and far-field tsunamis had the same source. If the source was a great M8.5 earthquake, then the geodetic measurements from one earthquake cycle cannot be applied to another. In light of the Indian Ocean Tsunami, however, the huge runup at Scotch Cap can no longer be regarded as a problem for an earthquake source, since runups in Sumatra last December were also far larger than expected. If, on the other hand, the source was a debris avalanche, it can only have occurred in the unsurveyed region. To satisfy the timing constraints, the tsunami had to be so large that the leading bore crossed the shelf with a Froude number of at least 2. The only way to make such a large tsunami is with an immense debris avalanche of over 200 km3. Such an avalanche is quite capable of explaining the far-field observations. To solve the enigma we shall have to complete the mapping of the upper Aleutian forearc, resurvey the near-field runup knowing that the area was also affected by the 1957 tsunami, and run push-core transects across the lowlands of Unimak Bight.

  3. Gate-tunable gigantic changes in lattice parameters and optical properties in VO2

    NASA Astrophysics Data System (ADS)

    Nakano, Masaki; Okuyama, Daisuke; Shibuya, Keisuke; Ogawa, Naoki; Hatano, Takafumi; Kawasaki, Masashi; Arima, Taka-Hisa; Iwasa, Yoshihiro; Tokura, Yoshinori

    2014-03-01

    The field-effect transistor provides an electrical switching function of current flowing through a channel surface by external gate voltage (VG). We recently reported that an electric-double-layer transistor (EDLT) based on vanadium dioxide (VO2) enables electrical switching of the metal-insulator phase transition, where the low-temperature insulating state can be completely switched to the metallic state by application of VG. Here we demonstrate that VO2-EDLT enables electrical switching of lattice parameters and optical properties as well as electrical current. We performed in-situ x-ray diffraction and optical transmission spectroscopy measurements, and found that the c-axis length and the infrared transmittance of VO2 can be significantly modulated by more than 1% and 40%, respectively, by application of VG. We emphasize that these distinguished features originate from the electric-field induced bulk phase transition available with VO2-EDLT. This work was supported by the Japan Society for the Promotion of Science (JSPS) through its ``Funding Program for World-Leading Innovative R&D on Science and Technology (FIRST Program).''

  4. 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

  5. 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-Galvn, P.

    2011-03-01

    Human DNA shows a complex structure with compositional features at many scales; the isochoreslong DNA segments (~105 bp) of relatively homogeneous guanine-cytosine (G + C) contentare 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.

  6. 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

  7. Gigantism in unique biogenic magnetite at the PaleoceneEocene 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; Lcken, 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 PaleoceneEocene 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 ?m long and hexaoctahedral prisms up to 1.4 ?m 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 bioavailabilitya product of dramatic changes in weathering and sedimentation patterns driven by severe global warmingdrove diversification of magnetite-forming organisms, likely including eukaryotes. PMID:18936486

  8. 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)

  9. 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

  10. 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

  11. 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…

  12. Gigantic ferroelectric polarization and magnetoelectric coupling in a ferrimagnetic oxide CaBaCo4O7

    NASA Astrophysics Data System (ADS)

    Mitchell, John; Caignert, Vincent; Maignan, Antoine; Singh, Kiran; Simon, Charles; Raveau, Bernard; Pralong, Valerie; Chapon, Laurent

    2013-03-01

    From both fundamental and applications points of view, improper ferroelectrics that exhibiting a strong coupling between polarization and magnetic structure are challenging the scientific community. Several multiferroics belonging to that category have been reported; however, they exhibit rather small values of electric polarization combined with low magnetic ordering temperatures. Only the CuO (tenorite), the ordered perovskites LBaCuFeO5 and the Z-type hexaferrites display magnetic ordering temperatures near room temperature, but they all suffer from polarization much smaller than that of proper ferroelectrics. Here, we report a ferrimagnetic cobaltite, CaBaCo4O7, crystallizing in a polar space group, which enters an improper ferroelectric phase below TC = 64 K. Single crystals of CaBaCo4O7 demonstrate the highest polarization value reported among improper ferroelectrics to date, reaching 10 mC/m2 at TC and approaching 16 mC/m2 at 8 K. Moreover a large magnetoelectric coupling coefficient is also evidenced near TC. This result points to routes for exploring new multiferroics among ferrimagnetic phases.

  13. 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

  14. 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

  15. 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.

  16. "A Gigantic Pedagogical Leap": The Process of Shifts during Three Learning Study Projects in Swedish Early Childhood Education

    ERIC Educational Resources Information Center

    Ljung-Djärf, Agneta; Wennås Brante, Eva; Holmqvist Olander, Mona

    2014-01-01

    Swedish early childhood education (ECE) offers a curriculum-based preschool for children aged one to five, and a preschool class for children aged six years. Activities in these programs have traditionally been based on play and having fun, avoiding structured activities with formal learning objectives. Due to indications that Swedish ECE has…

  17. 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.

  18. Radial head dislocation due to gigantic solitary osteochondroma of the proximal ulna: case report and literature review.

    PubMed

    Hamada, Yoshitaka; Hibino, Naohito; Horii, Emiko

    2015-06-01

    Developmental anterior dislocation of the radial head resulting from a congenital solitary osteochondroma of the proximal ulna is an extremely rare condition. We present a case of a 4-year-old girl with this condition affecting her right elbow, which was treated by a trapezoidal shortening osteotomy at the radial neck following an oblique ulnar osteotomy with angulation and elongation after a complete resection of the tumor mass. The child remained asymptomatic with symmetric carrying angles during 2.5 years of follow-up post-surgery. We discuss the nature of this condition and review the literature. PMID:26034449

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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, ...

  5. Growth hormone test

    MedlinePlus

    ... increased growth patterns called acromegaly in adults and gigantism in children. Too little growth hormone can cause ... high level of growth hormone may indicate: Acromegaly Gigantism Growth hormone resistance Pituitary tumor A low level ...

  6. Endocrine glands

    MedlinePlus

    ... Hypoglycemia Parathyroid: Tetany Renal calculi Excessive loss of minerals from bone Pituitary: Growth hormone deficiency Acromegaly Diabetes Gigantism Diabetes insipidus Cushing Disease Testes ...

  7. Fermi discovers giant bubbles in Milky Way - Duration: 93 seconds.

    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. 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.

  9. Pelvic Congestion Syndrome

    PubMed Central

    Durham, Janette D.; Machan, Lindsay

    2013-01-01

    Patients with pelvic congestion syndrome present with otherwise unexplained chronic pelvic pain that has been present for greater than 6 months, and anatomic findings that include pelvic venous insufficiency and pelvic varicosities. It remains an underdiagnosed explanation for pelvic pain in young, premenopausal, usually multiparous females. Symptoms include noncyclical, positional lower back, pelvic and upper thigh pain, dyspareunia, and prolonged postcoital discomfort. Symptoms worsen throughout the day and are exacerbated by activity or prolonged standing. Examination may reveal ovarian tenderness and unusual varicosities—vulvoperineal, posterior thigh, and gluteal. Diagnosis is suspected by clinical history and imaging that demonstrates pelvic varicosities. Venography is usually necessary to confirm ovarian vein reflux, although transvaginal ultrasound may be useful in documenting this finding. Endovascular therapy has been validated by several large patient series with long-term follow-up using standardized pain assessment surveys. Embolization has been shown to be significantly more effective than surgical therapy in improving symptoms in patients who fail hormonal therapy. Although there has been variation in approaches between investigators, the goal is elimination of ovarian vein reflux with or without direct sclerosis of enlarged pelvic varicosities. Symptom reduction is seen in 70 to 90% of the treated females despite technical variation. PMID:24436564

  10. 2006 Taiwan TLE campaign

    NASA Astrophysics Data System (ADS)

    Tsai, L.; Kuo, C.; Chen, Y.; Chen, Y.; Lee, Y.; Chou, R.; Lai, W.; Hsu, R.; Chen, A.; Su, H.

    2006-12-01

    Ground campaigns of transit luminous events (TLEs) in Taiwan started from 2001 and were repeated yearly ever since. In 2002, a new type of TLEs called gigantic jet was discovered above a convective system. During 2001-2005, there were six additional gigantic jets and more than six hundreds sprites were documented. In this paper, some interested results and progress of the 2006 Taiwan TLE campaign will be reported: 1. Two gigantic jets, which occurred above a frontal system over Taiwan, were recorded inside the NCKU campus which is located at the center of Tainan metropolitan area with more than one million residents. 2. A few sprites were recorded by a low-light-level CCD equipped with a blue filter which has a cutoff at 500nm. These sprites were very bright and occurred about 150-250km away from the observation site. Therefore, the attenuation of blue emission is less severe. In these blue band images the ionization channels in sprites can be discerned clearly. 3. A low-light level spectrograph was built and has captured two sprite spectra. However, the goal of capturing the spectrum of gigantic jets is yet to be fulfilled. 4. ISUAL images indicated that blue jets and gigantic jets may occur preferably above convective systems near typhoon. A compact imaging system was set up and deployed on an airplane operated by the Taiwan DOTSTAR projects. Only one nightly run was carried out this year and no event is recorded.

  11. A new giant species of Deltochilum subgenus Deltohyboma (Coleoptera, Scarabaeidae, Scarabaeinae) from Colombia, with notes on D. spinipes Paulian, 1938.

    PubMed

    Silva, Fernando A B; Vaz-de-Mello, Fernando Z

    2014-01-01

    Deltochilum (Deltohyboma) gigante sp. nov., from Parque Nacional Las Cuevas de los Guácharos, Huila, Colombia is described based on differences in external and genital morphology. Its diagnostic characters are provided and illustrated. Lectotype and paralectotypes for D. spinipes, a close relative to the new species, are designated. PMID:24871007

  12. 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.

  13. 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…

  14. Latinas in College: "Contra Viento y Marea" (Against Winds and Tides)

    ERIC Educational Resources Information Center

    Diaz De Sabates, Gabriela

    2007-01-01

    With the rapid demographic changes in the United States in general and in the state of Kansas in particular, educational institutions are challenged with a gigantic task: to educate a very diverse population with multifaceted linguistic and cultural backgrounds, needs, and challenges that is growing exponentially. To illustrate this demographic…

  15. 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…

  16. History of Indian launchers

    NASA Astrophysics Data System (ADS)

    Suresh, B. N.

    2008-07-01

    A multitude of inter-disciplinary technologies have been mastered indigenously for realizing a series of operational space launch vehicles. The vehicles range from relatively tiny Rohini sounding rockets to gigantic satellite launchers, PSLV and GSLV. This paper gives the challenges faced, lessons learned during various development phases and the step-by-step evolution of launch vehicle technologies in India.

  17. 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…

  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. Man, Controller of the Universe

    NASA Astrophysics Data System (ADS)

    Olowin, R. P.

    2011-06-01

    The Man, Controller of the Universe painted by the renowned Mexican artist Diego Rivera in the gigantic mural of the Palace of Fine Arts in Mexico City is overlooked by a telescope. We acknowledge this instrument as the Plaskett Telescope at the Dominion Astrophysical Observatory in Victoria, Canada.

  20. Data Grabbers.

    ERIC Educational Resources Information Center

    Albrecht, Bob; Firedrake, George

    1998-01-01

    Running experiments and grabbing experimental data are great ways to learn and teach science and mathematics. Data grabbers are instruments that capture physical data in electronic form for graphing and analysis in graphing calculators and computers. Describes some data grabbers and points to items in their gigantic support system. (PVD)

  1. 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

  2. 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…

  3. Third Stage (S-IVB) At KSC

    NASA Technical Reports Server (NTRS)

    1960-01-01

    A NASA technician is dwarfed by the gigantic Third Stage (S-IVB) as it rests on supports in a facility at KSC. The towering 363-foot Saturn V was a multi-stage, multi-engine launch vehicle standing taller than the Statue of Liberty. Altogether, the Saturn V engines produced as much power as 85 Hoover Dams.

  4. 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)

  5. 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…

  6. [Proteus syndrome].

    PubMed

    Benichou, J J; Labrune, B; Formanek, A; Denoix, C; Oger, P

    1990-01-01

    Two new cases of Proteus syndrome are reported. This congenital syndrome, first described in 1983, comprises gigantism of extremities, body hemihypertrophy, pigmented nevi and multiple tumors (subcutaneous, lipomas, hamartomas). This syndrome belongs to the same group as Recklinghausen disease, Maffucci or Klippel-Trenaunay syndromes. The prognosis is not well known but mostly depends on functional and psychologic consequences of important deformations. PMID:2206106

  7. 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,…

  8. 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…

  9. 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

  10. 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…

  11. Fossils and Dinosaurs--A Fully Integrated Instructional Unit.

    ERIC Educational Resources Information Center

    Kuehl, Matt; And Others

    This lesson plan for the second and third grades uses information on dinosaurs, their adaptations and survival, to provide science education for limited-English-proficient (LEP) students in San Diego, California. The primary text is "Los Dinosaurios Gigantes," a core literature book used in the school district. Lessons are based on the whole

  12. 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…

  13. 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

  14. 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

  15. 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…

  16. Infezioni virali in ginecologia: un problema risolto?

    PubMed

    Agnello, Antonella; Bevilacqua, Luciano; Ariviello, Rosa; Bandieramonte, Gaetano; Peroni, Mario; Simoncini, Ettore; Verdi, Piero; Zanardi, Claudio

    2016-06-01

    The aim of this observational study was to evaluate the effectiveness of a dietary integrator containing methionine, zinc, Echinacea angustifolia and E. purpurea, probiotics, and antioxidant factors (Immuno Gin) in the treatment of mild cervical dysplasia associated with human papillomavirus (HPV) infection. The study sample was 95 women (age range, 31-55 years) resident in various cities in Italy. Initial Pap test results showed abnormal changes in cervical cells described as atypical squamous cells of undetermined significance (ASC-US) and HPV infection in 23/95 women, 3 of which received the study product. Follow-up repeat Pap testing at 6 months returned normal test results in all 3. In 12 of the 20 women who did not receive treatment with the study product, the repeat Pap test at 6 months showed normal results, whereas persistence of lesions was observed in the other 8 women, with progression to low-grade squamous intraepithelial lesion (LSIL) in one case. Forty-five women presented initially with abnormal changes in cervical cells described as LSIL and HPV infection. Twenty received treatment with the study product; the repeat Pap test at 6 months showed normal results in 15 and no change in lesions in the other 5. Among the 25 women who did not receive treatment with the study product, the repeat Pap test at 6 months showed normal results in 13, whereas persistence of lesions was noted in the other 12, with progression to high-grade squamous intraepithelial lesion - moderate cervical intraepithelial lesion 2 (HSIL - CIN 2) in one case. Twenty-seven women with vulvoperineal condylomatosis received treatment with the study product, as described above, plus biophysical treatment of the lesions. At the 6-month follow-up assessment, no relapse of lesions occurred in 19, whereas relapse was noted in the other 8. Though the study sample is too small to draw statistically significant conclusions, the percentage of cases of lesion regression among the women treated with the study product was slightly higher than in those who did not receive treatment. Use of the study product may provide clinical benefit by stimulating immune defenses against HPV infection. PMID:27206065

  17. 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.

  18. 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

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

    NASA Astrophysics Data System (ADS)

    Dohm, J. M.; Casavant, R. R.; Strom, R. G.; Zimbelman, J. R.; Scott, D. H.

    2001-06-01

    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.

  20. Embedded ubiquitous services on hospital information systems.

    PubMed

    Kuroda, Tomohiro; Sasaki, Hiroshi; Suenaga, Takatoshi; Masuda, Yasushi; Yasumuro, Yoshihiro; Hori, Kenta; Ohboshi, Naoki; Takemura, Tadamasa; Chihara, Kunihiro; Yoshihara, Hiroyuki

    2012-11-01

    A Hospital Information Systems (HIS) have turned a hospital into a gigantic computer with huge computational power, huge storage and wired/wireless local area network. On the other hand, a modern medical device, such as echograph, is a computer system with several functional units connected by an internal network named a bus. Therefore, we can embed such a medical device into the HIS by simply replacing the bus with the local area network. This paper designed and developed two embedded systems, a ubiquitous echograph system and a networked digital camera. Evaluations of the developed systems clearly show that the proposed approach, embedding existing clinical systems into HIS, drastically changes productivity in the clinical field. Once a clinical system becomes a pluggable unit for a gigantic computer system, HIS, the combination of multiple embedded systems with application software designed under deep consideration about clinical processes may lead to the emergence of disruptive innovation in the clinical field. PMID:22855229

  1. 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.

  2. Saturn V First Stage (S-1C) At MSFC

    NASA Technical Reports Server (NTRS)

    1960-01-01

    This small group of unidentified officials is dwarfed by the gigantic size of the Saturn V first stage (S-1C) at the shipping area of the Manufacturing Engineering Laboratory at Marshall Space Flight Center in Huntsville, Alabama. The towering 363-foot Saturn V was a multi-stage, multi-engine launch vehicle standing taller than the Statue of Liberty. Altogether, the Saturn V engines produced as much power as 85 Hoover Dams.

  3. Mechanisms for chromosome segregation.

    PubMed

    Bouet, Jean-Yves; Stouf, Mathieu; Lebailly, Elise; Cornet, François

    2014-12-01

    Bacteria face the problem of segregating their gigantic chromosomes without a segregation period restricted in time and space, as Eukaryotes do. Segregation thus involves multiple activities, general or specific of a chromosome region and differentially controlled. Recent advances show that these various mechanisms conform to a “pair and release” rule, which appears as a general rule in DNA segregation. We describe the latest advances in segregation of bacterial chromosomes with emphasis on the different pair and release mechanisms. PMID:25460797

  4. 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 allometric effect of adaptive divergence in skull size, represented in the evolution of gigantism and dwarfism in habitat islands. PMID:22984399

  5. [Psychoanalysis and therapeutic treatment of schizophrenia].

    PubMed

    Chaperot, Christophe; Turdeanu, Lise

    2013-01-01

    The influence of psychoanalysis in the treatment of schizophrenic pathologies is significant in public sector psychiatry. The psychotic transfer is of a different style than with a traditional psychoanalytical treatment. Here, it is "dissociated" and its expression is diluted in space, across the different members of the teams and in time. The institution is therefore to be conceived as a gigantic diffracted couch comprising two functions: the "meeting function" and the "club function". PMID:23757888

  6. Reduction surgery using a combination of a stereolithographic model and navigation system for ossifying fibroma with secondary central giant cell granuloma.

    PubMed

    Arai, Yasuhiro; Chiba, Yoshihiro; Umeda, Shigeaki; Ohara, Yoshihito; Iwai, Toshinori; Komatsu, Masanori; Yabuki, Kenichiro; Sano, Daisuke; Oridate, Nobuhiko

    2016-04-01

    Both central giant cell granuloma (CGCG) and ossifying fibroma (OF) are relatively common diseases. The synchronous presentation of CGCG and OF is, however, an extremely rare occurrence. We present an unusual case with the synchronous presentation of these two diseases in the maxilla and introduce a surgical strategy based on a combination of the stereolithographic model and navigation system for the treatment of gigantic OF with secondary CGCG. PMID:26316138

  7. A case of a giant cystic lymphangioma mimicking acute appendicitis

    PubMed Central

    Eisawi, A; Otter, M; Asha, M; Al-Temimi, A

    2012-01-01

    Cystic lymphangiomas are rare tumours that can mimic various causes of acute abdomen including appendicitis. They exhibit variations in two characteristics on presentation: they can arise from a wide range of organs including various intra-abdominal structures and they can have a wide variation in size on presentation. We report a case of a gigantic cystic lymphangioma presenting as an acute abdomen closely mimicking acute appendicitis and we conduct a review of the relevant literature. PMID:22524917

  8. Heterokaryon analysis of a Cdc48-like gene, CpCdc48, from the chestnut blight fungus Cryphonectria parasitica demonstrates it is essential for cell division and growth.

    PubMed

    Ko, Yo-Han; So, Kum-Kang; Kim, Jung-Mi; Kim, Dae-Hyuk

    2016-03-01

    Functional analysis of a cell division cycle 48 (CDC48) ortholog, CpCdc48, from Cryphonectria parasitica was performed via construction of a CpCdc48-null mutant. Genotype analysis revealed that the putative CpCdc48-null mutant was a heterokaryotic transformant containing two different types of nuclei (i.e., one with the wild-type CpCdc48 allele and the other with the CpCdc48-null mutant allele). Although stable mycelial growth of the heterokaryotic transformant was observed on media containing hygromycin B, neither germination nor growth of the resulting spores was observed on selection media, suggesting that the CpCdc48 gene is essential. Microscopic analysis of germinated conidia from the heterokaryon demonstrated that although there were normal germinating spores due to the wild-type conidia, there were many residual conidia that did not germinate. However, with prolonged incubation, non-germinating conidia began to swell into gigantic globose spores. DAPI staining and FACS analysis of the gigantic spores revealed the presence of multiple nuclei. These gigantic conidia did not show any signs of polarized growth and underwent autolysis with further incubation. These findings indicate that the CpCdc48 gene is responsible for delayed cell cycle during spore germination, resulting in some karyokinesis, but not following spore cytokinesis. Thus, CpCdc48 is essential for cell division and polarized growth. PMID:26802617

  9. 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.

  10. 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

  11. 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

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

    NASA Astrophysics Data System (ADS)

    Jong-Ping, Hsu; Kazuo, O. Cottrell

    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.

  13. [The virtual reality simulation research of China Mechanical Virtual Human based on the Creator/Vega].

    PubMed

    Wei, Gaofeng; Tang, Gang; Fu, Zengliang; Sun, Qiuming; Tian, Feng

    2010-10-01

    The China Mechanical Virtual Human (CMVH) is a human musculoskeletal biomechanical simulation platform based on China Visible Human slice images; it has great realistic application significance. In this paper is introduced the construction method of CMVH 3D models. Then a simulation system solution based on Creator/Vega is put forward for the complex and gigantic data characteristics of the 3D models. At last, combined with MFC technology, the CMVH simulation system is developed and a running simulation scene is given. This paper provides a new way for the virtual reality application of CMVH. PMID:21089666

  14. 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

  15. 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.

  16. Mechanism of molecular exchange in diblock copolymer micelles: hypersensitivity to core chain length.

    PubMed

    Choi, Soo-Hyung; Lodge, Timothy P; Bates, Frank S

    2010-01-29

    Molecular exchange between spherical micelles formed from isotopically labeled diblock copolymers was investigated using time-resolved small-angle neutron scattering measurements. Temperature changes affect the micelle exchange rate R(t) consistent with melt dynamics for the core polymer. Varying the core block length N produces gigantic changes in R(t) due to the thermodynamic penalty associated with ejecting a core block into the surrounding solvent. This hypersensitivity, combined with modest polydispersity in N, leads to an approximately logarithmic R(t). PMID:20366740

  17. A real-time health monitoring system of offshore platform structure based on fieldbus CAN and OPC

    NASA Astrophysics Data System (ADS)

    He, Lin; Ou, Jinping; Yao, Wei; Tang, Wei

    2005-05-01

    Using control area network (CAN) technique and open connectivity (OPC) method, a sensor fieldbus is developed to acquire and preprocess the data came from structure for monitoring the damage. The OPC interface is added in sensor bus for information sharing. The algorithm of distance of storing-strategy data is embedded in the sensor fieldbus. A system of data acquisition and preprocessing based on the sensor fieldbus is presented and simulated it on the offshore platform. The result shows that the speed and efficiency of sensor fieldbus are reliable and robust when the gigantic data stream into the monitoring system.

  18. Problems of nuclear science and technology: the Soviet Union as a world nuclear power

    SciTech Connect

    Petrosy'ants, A.M.

    1981-01-01

    This book, written by the Chairman of the State Commission for the Utilization of Atomic Energy in the Soviet Union, tells about the Soviet Union as a world nuclear power, using atomic energy for peaceful purposes. The book shows the transformation of nuclear science and technology into a gigantic branch of the national economy. The fourth edition of the book (1st Edition in 1970, 2nd Edition in 1972, and the 3rd Edition in 1976) has been revised and augmented with new information reflecting the achievements of nuclear science and technology in the ninth and tenth Five-year periods.

  19. 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.

  20. 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 surface into the source slope while low bedding dip (ca. 19°) allowed kinematic freedom of a particularly thick sequence to move downslope. Prevention of gradual rockmass removal by smaller-magnitude, more frequent denudation ensured its preservation for later simultaneous failure. The overall failure surface (11°) cut across weaker beds and finally breached the Asmari carapace by break-out at the base of the source slope. Relative relief of the source slope on Kabir Kuh was modest (1350 m on average) indicating that uniform structural and topographic conditions along strike, shallow bedding dips, and the geomechnical properties of the source rock mass were more important in determining the magnitude of the landslide that forms the upper magnitude limit for subaerial landslides.

  1. 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.

  2. 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.

  3. A hexaicosametallic copper(II) phosphonate.

    PubMed

    Chandrasekhar, Vadapalli; Sahoo, Dipankar; Narayanan, Ramakirushnan Suriya; Butcher, Raymond J; Lloret, Franscesc; Pardo, Emilio

    2013-06-21

    Structure and characterization of [Cu26{2,3,5,6-(Me)4C6H-CH2-PO3}18(μ2-OH)4(μ3-OH)6(μ4-Cl)6(μ-OH2)2(OH2)2(MeCN)4]·6MeCN·15H2O (1) is reported. Complex 1 is the largest discrete molecular homometallic transition metal phosphonate assembly. Remarkably, this gigantic molecular phosphonate has been prepared at room temperature using a normal solution synthetic method. PMID:23660753

  4. 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.

  5. Molecular anisotropic magnetoresistance

    NASA Astrophysics Data System (ADS)

    Otte, Fabian; Heinze, Stefan; Mokrousov, Yuriy

    2015-12-01

    Using density functional theory calculations, we demonstrate that the effect of anisotropic magnetoresistance (AMR) can be enhanced by orders of magnitude with respect to conventional bulk ferromagnets in junctions containing molecules sandwiched between ferromagnetic leads. We study ballistic transport in metal-benzene complexes contacted by 3 d transition-metal wires. We show that a gigantic AMR can arise from spin-orbit coupling effects in the leads, drastically enhanced by orbital-symmetry filtering properties of the molecules. We further discuss how this molecular anisotropic magnetoresistance (MAMR) can be tuned by the proper choice of materials and their electronic properties.

  6. [Old phenotype and new genotypes. Pituitary adenomas].

    PubMed

    Gérard, C; Jedidi, H; Petrossians, P; Krzesinski, F; Daly, A; Beckers, A

    2015-11-01

    Gigantism and acromegaly, usually caused by a pituitary adenoma linked inappropriate secretion of growth hormone (GH), are generally considered as very rare diseases, even if, according to some authors, their cumulative prevalence is about 1/5000. Starting from the historical case of a giant from Liège we shall describe the different types of GH pituitary adenomas and their pathophysiology. We shall particularly discuss rare forms of inherited GH secreting pituitary adenomas like the FIPA (familial inherited isolated pituitary adenomas) and the X-LAG (X linked acrogigantism), both described for the first time in Liège, in 2000 and 2014, respectively. PMID:26738269

  7. Magnetostriction simulation using anisotropic vector Preisach-type models

    SciTech Connect

    Adly, A.A.; Mayergoyz, I.D.

    1996-09-01

    Magnetic materials exhibiting gigantic magnetostriction, especially Terfenol, are currently being widely used in fine positioning and active vibration damping devices. By involving accurate magnetostriction models during design stages, precision of such devices may be significantly enhanced. In this paper a straight-forward approach that employs anisotropic vector Preisach-type hysteresis models in simulating field-stress effects on magnetic materials is presented. Formulation of the proposed model is given and its identification problem is solved. The presented approach has been numerically implemented and numerous digital computer simulations have been performed for Terfenol material. Sample simulation results as well as comparisons with experimentally observed magnetostriction curves are reported in the paper.

  8. [The ultrastructural characteristics of Neisseria meningitidis strains isolated in different forms of infection].

    PubMed

    Vysotski?, V V; Smirnova-Mutusheva, M A; Mishina, A I

    1995-01-01

    The electron microscopic study of cell populations of the first generation of several N.meningitidis strains, isolated from humans and grown on artificial culture medium (Hottinger's serum agar) has made it possible to establish that these organisms are morphologically heterogeneous. It was manifested by the presence of 7 morphological variants of cells in their cultures (different strains have different proportions of these variants): (a) "normal" and similar to normal diplococcal variants; (b) atypically dividing cells; (c) spheroplastic forms; (d) protoplastic forms (typical and atypical); (e) variably gemmating forms; (f) microforms and (g) gigantic forms. These data are of interest for the microbiological diagnosis of meningitis. PMID:9381865

  9. 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

  10. 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

  11. [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

  12. 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

  13. 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

  14. 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

  15. Upward electrical discharges observed above Tropical Depression Dorian

    NASA Astrophysics Data System (ADS)

    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.

  16. Physicochemical, digestibility and structural characteristics of starch isolated from banana cultivars.

    PubMed

    Agama-Acevedo, Edith; Nuñez-Santiago, Maria C; Alvarez-Ramirez, José; Bello-Pérez, Luis A

    2015-06-25

    Banana starches from diverse varieties (Macho, Morado, Valery and Enano Gigante) were studied in their physicochemical, structural and digestibility features. X-ray diffraction indicated that the banana starches present a B-type crystallinity pattern, with slight difference in the crystallinity level. Macho and Enano Gigante starches showed the highest pasting temperatures (79 and 78°C, respectively), whilst Valery and Morado varieties presented a slight breakdown and higher setback than the formers. Morado starch presented the highest solubility value and Valery starch the lowest one. The swelling pattern of the banana starches was in agreement with their pasting profile. All banana starches showed a shear-thinning profile. The resistant starch (RS) fraction was the main fraction in the uncooked banana starches. Morado variety showed the highest amount of slowly digestible starch (SDS) and the lowest RS content reported until now in banana starches. Banana starch cooked samples presented an important amount of SDS and RS. Molecular weight and gyration radius of the four banana starches ranged between 2.88-3.14×10(8)g/mol and 286-302nm, respectively. The chain-length distributions of banana amylopectin showed that B1 chains (DP 13-24) is the main fraction, and an important amount of long chains (DP≥37) are present. The information generated from this study can be useful to determine banana varieties for starch isolation with specific functionality. PMID:25839789

  17. Optimal growth strategies under divergent predation pressure.

    PubMed

    Aikio, S; Herczeg, G; Kuparinen, A; Meril, J

    2013-01-01

    The conditions leading to gigantism in nine-spined sticklebacks Pungitius pungitius were analysed by modelling fish growth with the von Bertalanffy model searching for the optimal strategy when the model's growth constant and asymptotic fish size parameters are negatively related to each other. Predator-related mortality was modelled through the increased risk of death during active foraging. The model was parameterized with empirical growth data of fish from four different populations and analysed for optimal growth strategy at different mortality levels. The growth constant and asymptotic fish size were negatively related in most populations. Optimal fish size, fitness and life span decreased with predator-induced mortality. At low mortality, the fitness of pond populations was higher than that of sea populations. The differences disappeared at intermediate mortalities, and sea populations had slightly higher fitness at extremely high mortalities. In the scenario where all populations mature at the same age, the pond populations perform better at low mortalities and the sea populations at high mortalities. It is concluded that a trade-off between growth constant and asymptotic fish size, together with different mortality rates, can explain a significant proportion of body size differentiation between populations. In the present case, it is a sufficient explanation of gigantism in pond P. pungitius. PMID:23331153

  18. 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

  19. Development of high purity large forgings for nuclear power plants

    NASA Astrophysics Data System (ADS)

    Tanaka, Yasuhiko; Sato, Ikuo

    2011-10-01

    The recent increase in the size of energy plants has been supported by the development of manufacturing technology for high purity large forgings for the key components of the plant. To assure the reliability and performance of the large forgings, refining technology to make high purity steels, casting technology for gigantic ingots, forging technology to homogenize the material and consolidate porosity are essential, together with the required heat treatment and machining technologies. To meet these needs, the double degassing method to reduce impurities, multi-pouring methods to cast the gigantic ingots, vacuum carbon deoxidization, the warm forging process and related technologies have been developed and further improved. Furthermore, melting facilities including vacuum induction melting and electro slag re-melting furnaces have been installed. By using these technologies and equipment, large forgings have been manufactured and shipped to customers. These technologies have also been applied to the manufacture of austenitic steel vessel components of the fast breeder reactors and components for fusion experiments.

  20. 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.

  1. 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.

  2. Geological and Hydrodynamical Examination of the Bathyal Tsunamigenic Origin of Miocene Conglomerates in Chita Peninsula, Central Japan

    NASA Astrophysics Data System (ADS)

    Tachibana, Toru; Tsuji, Yoshinobu

    2011-06-01

    A conglomerate appears on a rocky coast called "Tsubutega-ura Coast", located on the southwestern coast near the southern tip of the Chita Peninsula, Aichi Prefecture, central Japan. The conglomerate belongs to Miocene sedimentary rocks termed the Morozaki Group. The conglomerate includes meter-scale boulders, indicating that it was formed by an extraordinary event. In the geological investigation, we observed that the conglomerate shows alternate changes of paleocurrent directions between seaward and landward. This feature is supposed to be formed by tsunami currents. In the hydrodynamical investigation, we obtained following results: (1) the lowest limit of a current velocity to move a boulder of about 3 m in diameter would be about 2-3 m/s, (2) the speed of tsunami currents reproduced by tsunami simulation exceeds 3 m/s at 300 m in depth when the tsunami is generated by a gigantic earthquake with magnitude 9.0 or more, (3) the transport distance of the boulder would be several hundred meters to several kilometers by one tsunami event caused by a gigantic earthquake. We conclude that tsunamis best explain the formation of the conglomerate deposited in upper bathyal environments about 200-400 m depth, both from geological and hydrodynamical viewpoints.

  3. 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.

  4. 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.%.

  5. [Relationship between disaster stress and peptic ulcers].

    PubMed

    Kanno, Takeshi; Iijima, Katsunori; Koike, Tomoyuki; Shimosegawa, Tooru

    2015-07-01

    There had been several reports about the increasing of peptic ulcers under a large-scale disaster or a war. But in human, it was still unclear that a severe psychological stress itself cause peptic ulcer independently of two major causes (Helicobacter pylori infection and nonsteroidal anti-inflammatory drugs). After Great East Japan earthquake in March 11th, 2011, one of the five most powerful earthquakes in the world since modern record keeping began in 1900, we also noticed remarkable increasing of patients with peptic ulcer in wide stricken area. Reports after this gigantic earthquake gave us two new important viewpoints. Disaster (psychological) stress possibly induce peptic ulcer independently of two major causes. And, people living in refugee shelter immediately after a disaster are strong risk group of peptic ulcer bleeding as well as an intake of anti-thrombotic agents. PMID:26165082

  6. Fluvial sandstone beds in Petrified Forest Member of Upper Triassic Chinle Formation, northwest New Mexico and northeast Arizona

    SciTech Connect

    Robertson, J.F. )

    1989-09-01

    Distribution, lithology, and fluvial style of sandstone and conglomerate beds in the upper part of the Petrified Forest Member of the Chinle Formation provide new interpretations of Chinle stratigraphy and environments of deposition. Newly described sandstone beds near Taaiylone, Mitchell Draw, and Crazy Woman Canyon in the Grants-Gallup region, lie, respectively, 60, 110, and 180 m stratigraphically above the top of the widespread Sonsela Sandstone Bed. The Correo Sandstone Bed, exposed on the south flank of Mesa Gigante, 75 km east-southeast of Grants, has been miscorrelated with the sandstone at Mitchell Draw. Subsurface data indicate that the Correo occurs stratigraphically above the other sandstone beds, near the top of the Petrified Forest Member.

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

    PubMed

    Durst, Paul A P; Roth, V Louise

    2015-07-01

    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

  8. 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.

  9. Geophysics could explain Ancient Maya Myth

    NASA Astrophysics Data System (ADS)

    Bruchez, Margaret Sabom

    According to Maya mythology, the splendor of the principal entity, the Feathered Serpent, is exalted at Lake Atitlán in southwestern Guatemala. A chance look at a phenomenon in the natural environment reveals the possible geophysical basis of this myth.More than poetic fancy, the flight of the Feathered Serpent could refer to the dissipation of a soliton wave formed in the 130-km2 caldera lake. In the myth, recounted in the sixteenth century document los anales de los caqchiqueles, the newly acceded leader of the Kaqchikel-speaking Maya tribe rises from the lake transformed as the Feathered Serpent [Recinos and Goetz, 1953, p. 76]. Residents claim a gigantic serpent, Xocomil, still lives in the waters.

  10. Geophysics Could Explain Ancient Maya Myth

    NASA Astrophysics Data System (ADS)

    Sabom Bruchez, Margaret

    2005-03-01

    According to Maya mythology, the splendor of the principal entity, the Feathered Serpent, is exalted at Lake Atitlán in southwestern Guatemala. A chance look at a phenomenon in the natural environment reveals the possible geophysical basis of this myth. More than poetic fancy, the flight of the Feathered Serpent could refer to the dissipation of a soliton wave formed in the 130-km2 caldera lake. In the myth, recounted in the sixteenth century document los anales de los caqchiqueles, the newly acceded leader of the Kaqchikel-speaking Maya tribe rises from the lake transformed as the Feathered Serpent [Recinos and Goetz, 1953, p. 76]. Residents claim a gigantic serpent, Xocomil, still lives in the waters.

  11. 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?

  12. 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.

  13. 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).

  14. 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

  15. Tetradecacobalt(II)-containing 36-niobate [Co14(OH)16(H2O)8Nb36O106]20- and its photocatalytic H2 evolution activity.

    PubMed

    Niu, Jingyang; Li, Fang; Zhao, Junwei; Ma, Pengtao; Zhang, Dongdi; Bassil, Bassem; Kortz, Ulrich; Wang, Jingping

    2014-08-01

    A gigantic Co14-containing 36-niobate, Na12K8[Co14(OH)16(H2O)8Nb36O106]⋅71H2O (1), has been prepared by the hydrothermal method and structurally characterized. Polyanion [Co14(OH)16(H2O)8Nb36O106](20-) (1 a) comprises a central Co7 core, surrounded by another seven isolated Co(2+) ions and six Lindqvist-type (Nb6O19) hexaniobate fragments. This is the first example of a high-nuclear cobalt-cluster-containing polyoxoniobate. The photocatalytic H2 evolution activity of Pt-loaded 1 was observed in methanol solution under irradiation using a 300 W Xe lamp. PMID:25043175

  16. 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

  17. 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

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

    PubMed

    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. PMID:18523747

  19. 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.

  20. 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

  1. 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

  2. Morphological divergence in a continental adaptive radiation: South American ovenbirds of the genus Cinclodes

    USGS Publications Warehouse

    Rader, Jonathan A.; Dillon, Michael E.; Chesser, 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.

  3. 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.

  4. 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

  5. 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.

  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. 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

  8. 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

  9. Critical dynamics and domain motion from permittivity of the electronic ferroelectric (TMTTF)2AsF6

    NASA Astrophysics Data System (ADS)

    Brazovskii, Serguei; Monceau, Pierre; Nad, Felix Ya.

    2015-03-01

    The quasi one-dimensional organic conductor (TMTTF)2AsF6 shows the charge ordering transition at TCO=101 K to a state of the ferroelectric Mott insulator which is still well conducting. We present and interpret the experimental data on the gigantic dielectric response in the vicinity of TCO, concentrating on the frequency dependence of the inverse 1/ε of the complex permittivity ε=ε‧+iε‧‧. Surprisingly for a ferroelectric, we could closely approach the 2nd order phase transition and to deeply reach the critical dynamics of the polarization. We could analyze the critical slowing-down when approaching TCO from both sides and to extract the anomalous power law for the frequency dependence of the order parameter viscosity. Moreover, below TCO we could extract a sharp absorption feature coming from a motion of domain walls which shows up at a frequency well below the relaxation rate.

  10. Petroleum, alcohol, and energy substitution in Brazil: Theoretical and empirical issues

    SciTech Connect

    Biller, D.

    1991-01-01

    As in other Latin American nations, the petroleum industry has always been surrounded by controversy in Brazil. Issues related to exploration, exploitation, and import of crude have received special attention by Brazilian decision makers. In the past decade, an additional relevant issue was brought into play by the oil crisis. An import substitution program for energy was implemented by the development of alternative indigenous energy sources. Among these sources, sugarcane was viewed as a reliable renewable resource for the production of fuel alcohol and, very recently, of electricity. Brazil engaged in a gigantic program of fuel substitution, which is now facing severe problems due to the fall of petroleum prices. This study analyzes the recent energy import substitution program in Brazil, specifically concentrating on microeconomic and environmental aspects of fuel substitution.

  11. 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

  12. Análisis del espectro infrarrojo del polvo interestelar asociado con cúmulos globulares y de su evolución temporal

    NASA Astrophysics Data System (ADS)

    Pellizza, L. J.; Forte, J. C.; Carpintero, D.

    El trabajo que se presenta investiga la dinámica de las partículas de polvo interestelar eyectadas por estrellas gigantes rojas en un cúmulo globular utilizando simulaciones numéricas de su interacción con el campo gravitatorio y con la radiación electromagnética de las estrellas. Se pretende con ello determinar la distribución espacial de ese material como una función del tiempo en un sistema similar a NGC 104 (47 Tuc). A partir de la distribución espacial resultante se obtuvo el espectro infrarrojo integrado el cual sugiere que el máximo contraste con la radiación estelar ocurre en longitudes de onda cercanas a 300 μm y que decrece rápidamente hacia longitudes de onda menores, en las que suelen realizarse las observaciones.

  13. 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

  14. 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.

  15. 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

  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. Competition and constraint drove Cope's rule in the evolution of giant flying reptiles.

    PubMed

    Benson, Roger B J; Frigot, Rachel A; Goswami, Anjali; Andres, Brian; Butler, Richard J

    2014-01-01

    The pterosaurs, Mesozoic flying reptiles, attained wingspans of more than 10 m that greatly exceed the largest birds and challenge our understanding of size limits in flying animals. Pterosaurs have been used to illustrate Cope's rule, the influential generalization that evolutionary lineages trend to increasingly large body sizes. However, unambiguous examples of Cope's rule operating on extended timescales in large clades remain elusive, and the phylogenetic pattern and possible drivers of pterosaur gigantism are uncertain. Here we show 70 million years of highly constrained early evolution, followed by almost 80 million years of sustained, multi-lineage body size increases in pterosaurs. These results are supported by maximum-likelihood modelling of a comprehensive new pterosaur data set. The transition between these macroevolutionary regimes is coincident with the Early Cretaceous adaptive radiation of birds, supporting controversial hypotheses of bird-pterosaur competition, and suggesting that evolutionary competition can act as a macroevolutionary driver on extended geological timescales. PMID:24694584

  19. 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.

  20. 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.; Lrz, 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.

  1. 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

  2. 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.

  3. A review of the osteopetroses.

    PubMed Central

    Beighton, P.; Horan, F.; Hamersma, H.

    1977-01-01

    The osteopetroses are a group of conditions which are characterized by varying combinations of bony sclerosis and modelling defects. Classical osteopetrosis may be inherited as an autosomal dominant or autosomal recessive: the former variety is benign, heterogeneous and comparatively common, while the latter is precocious, potentially lethal and rare. Many other craniotubular dysplasias and hyperostoses are loosely grouped with the osteopetroses. The commonest of these is the autosomal dominant form of craniometaphyseal dysplasia, while the others which are well known include Pyle disease, and van Buchem disease. Sclerosteosis is a progressive condition in which massive cranial thickening is associated with syndactyly and gigantism. Each of these disorders has specific clinical and radiographic features, which permit recognition. Diagnostic accuracy is crucial for treatment, prognostication and effective genetic management. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 PMID:335376

  4. 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.

  5. 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

  6. Genetic engineering of modular PKSs: from combinatorial biosynthesis to synthetic biology.

    PubMed

    Weissman, Kira J

    2016-02-01

    Covering: up to 2015Multienzyme polyketide synthases (PKSs) are molecular-scale assembly lines which construct complex natural products in bacteria. The underlying modular architecture of these gigantic catalysts inspired, from the moment of their discovery, attempts to modify them by genetic engineering to produce analogues of predictable structure. These efforts have resulted in hundreds of metabolites new to nature, as detailed in this review. However, in the face of many failures, the heady days of imagining the possibilities for a truly 'combinatorial biosynthesis' of polyketides have faded. It is now more appropriate to talk about 'PKS synthetic biology' with its more modest goals of delivering specific derivatives of known structure in combination with and as a complement to synthetic chemistry approaches. The reasons for these failures will be discussed in terms of our growing understanding of the three-dimensional architectures and mechanisms of these systems. Finally, some thoughts on the future of the field will be presented. PMID:26555805

  7. In vitro meat production system: why and how?

    PubMed

    Sharma, Shruti; Thind, Sukhcharanjit Singh; Kaur, Amarjeet

    2015-12-01

    Due to the nutritional importance and the sustained popularity of meat as a foodstuff, the livestock production sector has been expanding incessantly. This exponential growth of livestock meat sector poses a gigantic challenge to the sustainability of food production system. A new technological breakthrough is being contemplated to develop a substitute for livestock meat. The idea is to grow meat in a culture in the lab and manipulate its composition selectively. This paper aims to discuss the concept of In Vitro Meat production system, articulate the underlying technology and analyse the context of its implications, as proposed by several scientists and stakeholders. The challenges facing this emerging technology have also been discussed. PMID:26604337

  8. 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

  9. Saramago's All the Names and the epidemiological dream.

    PubMed

    Almeida-Filho, Naomar

    2004-09-01

    Language is crucial for all established scientific disciplines in contemporary society, particularly epidemiology. Portuguese writer Saramago wrote All the Names, a book about the Conservatória, a gigantic registry that stores the whole life of an entire population. A parallel is made with the first social observatories that used entire populations for systematic observation, permitting the development of epidemiological methodology. Such "epidemiological dream" almost became true in virtual form with the introduction of electronic data processing. The central thesis of this paper is that Saramago's Conservatória allegory might be interpreted as akin to the virtual world construed by epidemiological science. Specifically, it is about abstract realities (or theoretical environments) that by definition are necessary for the process of scientific inquiry, particularly when oriented by knowledge production through observational strategies. Reading Saramago, the epidemiological virtualscape may be envisaged, more imaginary than it is usual to imagine and more real than it is usual to realise. PMID:15310798

  10. 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

  11. 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.

  12. 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

  13. The Acraman impact structure: Estimation of the diameter by the ejecta layer thickness

    NASA Technical Reports Server (NTRS)

    Gurov, E. P.

    1993-01-01

    The big role of gigantic craters formation in geological history of the Earth was established by the example of the K/T boundary event. The discovery of the iridium anomaly in the sedimentary rocks of Vendian in the western part of Ukrainian shield allows to suppose its origin in connection with the great impact of that time. The only big impact structure of that age is the Acraman Crater in south-eastern part of Australia. The Acraman Crater is presented by deeply eroded structure, original diameter of which it is difficult to determine. By geological and morphological data the Acraman Crater is presented by an inner ring 30 km in diameter, an intermediate ring 90 km in diameter, and an outer ring about 150-160 km in diameter.

  14. 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.

  15. 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.

  16. 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

  17. Brazilian distribution of Amblyomma varium Koch, 1844 (Acari: Ixodidae), a common parasite of sloths (Mammalia: Xenarthra).

    PubMed

    Marques, Sandro; Barros-Battesti, Darci Moraes; Faccini, João Luiz Horacio; Onofrio, Valeria Castilho

    2002-12-01

    Amblyomma varium, commonly known in Brazil as the "carrapato-gigante-da-pregui a" (sloth's giant tick) is found from southern Central America to Argentina. The present study adds information on the geographical distribution of A. varium, as well as on their hosts, based on material deposited in the main Brazilian collections and on the available literature. Eighty-two vials, containing 191 adult specimens, deposited in five Acari collections between 1930 and 2001, were examined. These vials included data on the host and collection localities. The biology of A. varium is unknown. However it is known that, during the adult stage, the tick presents a high host specificity and is found almost exclusively on the sloths Bradypus tridactylus, B. variegatus, B.torquatus (Bradypodidae), Choloepus hoffmanni and C. didactylus (Megalonychidae). Based on the material examined, the states of Rond nia, Amazonas, Bahia and Alagoas are newly assigned to geographic distribution of A. varium in Brazil. PMID:12563481

  18. A clinically novel AIP mutation in a patient with a very large, apparently sporadic somatotrope adenoma

    PubMed Central

    Daly, Adrian F; Quinones-Hinojosa, Alfredo; Thiry, Albert; Beckers, Albert

    2014-01-01

    Summary Heterozygous germline inactivating mutations in the aryl hydrocarbon receptor-interacting protein (AIP) gene lead to pituitary adenomas that most frequently present in the setting of familial isolated pituitary adenoma syndrome, usually as somatotropinomas and prolactinomas. More recently, they have been found in a significant percentage of young patients presenting with pituitary macroadenoma without any apparent family history. We describe the case of a 19-year-old man who presented with a gigantic somatotropinoma. His family history was negative. His peripheral DNA showed a heterozygous AIP mutation (p.I13N), while tumor tissue only had the mutated allele, showing loss of heterozygosity (LOH) and suggesting that the mutation caused the disease. Learning points AIP mutations may be observed in sporadic somatotrope adenomas occurring in young patients.LOH is a strong indicator that an AIP variant is disease causing.Somatotrope adenomas in carriers of AIP mutations are generally larger and more difficult to cure. PMID:25136448

  19. Polarizacin lineal en estrellas simbiticas

    NASA Astrophysics Data System (ADS)

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

    Se presenta un estudio de polarizacin lineal en las bandas UBVRI de un grupo de estrellas simbiticas, a fin de analizar el comportamiento del grado de polarizacin y del ngulo de posicin en funcin de la longitud de onda. En aquellos sistemas observados repetidas veces, se analizan adems variaciones temporales en los parmetros de polarizacin. En base a este comportamiento se determina si la polarizacin observada es puramente interestelar o si existe una contribucin de polarizacin, intrnseca al objeto. La muestra de objetos estudiados presenta ciertas caractersticas comunes, es decir, son sistemas simbiticos tipo D, cuyas respectivas componentes gigantes son variables tipo Mira y adems presentan nebulosas ionizadas extendidas con morfologa y dimensiones conocidas. Esto es de importancia ya que el conocimiento de la estructura del gas extendido permite interpretar la geometra de scattering que produce la polarizacin observada. Las observaciones fueron realizadas con el Fotopolarmetro de Torino adosado al telescopio de 2.15 m del CASLEO.

  20. 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

  1. ?Li-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

  2. 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

  3. Angiomyolipoma of the Thoracic Wall: An Extremely Rare Diagnostic Challenge

    PubMed Central

    Gemenetzis, Georgios; Kostidou, Eleni; Goula, Kalliroi; Smyrniotis, Vassilios; Arkadopoulos, Nikolaos

    2014-01-01

    Extrarenal angiomyolipoma (AML) is an extremely uncommon lesion, accounting for less than 9% of all angiomyolipomas. We present a previously unreported case of a rarely located gigantic extrarenal angiomyolipoma at the posterolateral chest wall of a 35-year-old woman. Clinically, the lesion had all the characteristics of a benign tumor, being soft in palpation, painless, and growing in size in a slow rate. Histologically, the lesion consisted of convoluted thick-walled blood vessels without an elastic layer, interlacing fascicles of smooth muscle, and mature adipose tissue, features consistent with an angiomyolipoma. The mass was surgically removed, without any postoperative complications, and the patient has an uneventful postoperative course. Signs of local recurrence have not been observed. The purpose of this brief report is to point out the necessity of including angiomyolipoma in the differential diagnosis of adipose layer lesions. PMID:25276465

  4. Velocity of domain-wall motion during polarization reversal in ferroelectric thin films: Beyond Merz's Law

    NASA Astrophysics Data System (ADS)

    Meng, Qingping; Han, Myung-Geun; Tao, Jing; Xu, Guangyong; Welch, David O.; Zhu, Yimei

    2015-02-01

    The motion of domain walls (DWs) is critical to switching kinetics in ferroelectric (FE) materials. Merz's law, dependent only on the applied electric field, cannot explain recent experimental observations in FE thin films because these experiments showed that the DW velocity depends not only on the strength of the applied electric field but also on size of the reversal domain. In this paper, we derive a model to understand the dominant factors controlling the velocity of FE DWs. Our calculations reveal that the DW velocities are not only a function of the strength of the electric field but also decay exponentially with the increasing characteristic time of the measurement or the size of the growing domain. Our observations can naturally explain the gigantic variation reported in the literature, over 15 orders of magnitude, in the experimentally measured DW velocities and the formation of the stripe shape of FE domains.

  5. 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

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

    PubMed

    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

  7. Fotometría CCD en el campo del cúmulo abierto Ruprecht 58

    NASA Astrophysics Data System (ADS)

    Giorgi, E. E.; Vázquez, R. A.; Seggewiss, W.; Ostrov, P.; Solivella, G. R.

    La región de Vela-Puppis contiene varios cúmulos cuyo estudio puede brindarnos información acerca de la cinemática y el estado evolutivo de la población estelar en las zonas externas del disco galáctico. A través de observaciones CCD en los filtros UBV en el campo del cúmulo abierto Ruprecht 58 (α2000= 8h 14m 41s, δ2000=-31o 57'), se han determinado por primera vez los parámetros fundamentales de este cúmulo tales como distancia, enrojecimiento y edad. Se analiza también la estructura de su secuencia principal y la presencia de gigantes y binarias.

  8. Topological fate of edge states of single Bi bilayer on Bi(111)

    NASA Astrophysics Data System (ADS)

    Yeom, Han Woong; Jin, Kyung-Hwan; Jhi, Seung-Hoon

    2016-02-01

    We address the topological nature of electronic states of step edges of Bi(111) films by first-principles band structure calculations. We confirm that the dispersion of step-edge states reflects the topological nature of underlying films, which become topologically trivial at a thickness larger than eight bilayers. This result clearly conflicts with recent claims that the step-edge state at the surface of a bulk Bi(111) crystal or a sufficiently thick Bi(111) film represents nontrivial edge states of the two-dimensional topological insulator phase expected for a very thin Bi(111) film. The trivial step-edge states have a gigantic spin splitting of one-dimensional Rashba bands and substantial intermixing with electronic states of the bulk, which might be exploited further.

  9. 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

  10. A basal dromaeosaurid and size evolution preceding avian flight.

    PubMed

    Turner, Alan H; Pol, Diego; Clarke, Julia A; Erickson, Gregory M; Norell, Mark A

    2007-09-01

    Fossil evidence for changes in dinosaurs near the lineage leading to birds and the origin of flight has been sparse. A dinosaur from Mongolia represents the basal divergence within Dromaeosauridae. The taxon's small body size and phylogenetic position imply that extreme miniaturization was ancestral for Paraves (the clade including Avialae, Troodontidae, and Dromaeosauridae), phylogenetically earlier than where flight evolution is strongly inferred. In contrast to the sustained small body sizes among avialans throughout the Cretaceous Period, the two dinosaurian lineages most closely related to birds, dromaeosaurids and troodontids, underwent four independent events of gigantism, and in some lineages size increased by nearly three orders of magnitude. Thus, change in theropod body size leading to flight's origin was not unidirectional. PMID:17823350

  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. 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.

  13. 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.

  14. Fates of the most massive primordial stars

    NASA Astrophysics Data System (ADS)

    Chen, Ke-Jung; Heger, Alexander; Almgren, Ann; Woosley, Stan

    2012-09-01

    We present our results of numerical simulations of the most massive primordial stars. For the extremely massive non-rotating Pop III stars over 300Msolar, they would simply die as black holes. But the Pop III stars with initial masses 140 - 260Msolar may have died as gigantic explosions called pair-instability supernovae (PSNe). We use a new radiation-hydrodynamics code CASTRO to study evolution of PSNe. Our models follow the entire explosive burning and the explosion until the shock breaks out from the stellar surface. In our simulations, we find that fluid instabilities occurred during the explosion. These instabilities are driven by both nuclear burning and hydrodynamical instability. In the red supergiant models, fluid instabilities can lead to significant mixing of supernova ejecta and alter the observational signature.

  15. Giant Magnetocaloric Effect in the Double-perovskite Gd2 NiMnO6

    NASA Astrophysics Data System (ADS)

    Moon, Jae Young; Kim, Mi Kyung; Oh, Dong Kun; Oh, Sang Hyup; Lee, Nara; Choi, Young Jai

    We have synthesized single crystal of Gd2NiMnO6(GNMO) by the Bi-flux method and investigated magnetocaloric effect in them by magnetic measurements. Magnetic susceptibility of GNMO increases smoothly as temperature decrease and ferromagnetic order occurs below 135 K, and additional anomaly show at low temperature, indicative of the onset of Gd3+ spin arrangement. At the temperature, magnetic entropy change, - ΔSM, with the field changes of 0-9 T, calculated from isothermal M(H) data using Maxwell relation, exhibits sharp peak. This peak is gigantic and cryogenic, these make GNMO promising cryogenic magnetic refrigerant materials. Giant Magnetocaloric Effect in the Double-perovskite Gd2 NiMnO6 .

  16. 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.

  17. Groundwater formation of martian valleys.

    PubMed

    Malin, M C; Carr, M H

    1999-02-18

    The martian surface shows large outflow channels, widely accepted as having been formed by gigantic floods that could have occurred under climatic conditions like those seen today. Also present are branching valley networks that commonly have tributaries. These valleys are much smaller than the outflow channels and their origins and ages have been controversial. For example, they might have formed through slow erosion by water running across the surface, either early or late in Mars' history, possibly protected from harsh conditions by ice cover. Alternatively, they might have formed through groundwater or ground-ice processes that undermine the surface and cause collapse, again either early or late in Mars' history. Long-duration surface runoff would imply climatic conditions quite different from the present environment. Here we present high-resolution images of martian valleys that support the view that ground water played an important role in their formation, although we are unable as yet to establish when this occurred. PMID:10050852

  18. [The limited viewpoint, the media--a medical aggravation].

    PubMed

    Imdahl, H

    1988-01-01

    The reduced view results from a discrepancy between the gigantic supply of the media and the limited capacity of the consumer to intellectually process a wealth of impressions. These remain as gross clichees, which the media repeatedly use as thematically fixed, emotionally charged currency. These tendencies reach everywhere, determining which groups of facts we see and in what light we see them. Before the advent of the mass media, opinions were based on direct observations made in a human context. The mass media, in contrast, supply an indirect, impersonal and machine based opinion to an overwhelmingly anonymous public. Understanding is only possible by reducing complexity, mainly by rigorous selection. We live without reflection in a world of simplified pictures, ideas and contexts, becoming aware of their faults only when we are personally involved. PMID:3236964

  19. 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

  20. 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.

  1. 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

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

    PubMed

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

    2007-07-24

    We calculate the flight performance of the gigantic volant bird Argentavis magnificens from the upper Miocene ( approximately 6 million years ago) of Argentina using a computer simulation model. Argentavis was probably too large (mass approximately 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 degrees 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. Giant flexoelectricity of bent-core nematic liquid crystals.

    PubMed

    Harden, J; Mbanga, B; Eber, N; Fodor-Csorba, K; Sprunt, S; Gleeson, J T; Jákli, A

    2006-10-13

    Flexoelectricity is a coupling between orientational deformation and electric polarization. We present a direct method for measuring the flexoelectric coefficients of nematic liquid crystals (NLCs) via the electric current produced by periodic mechanical flexing of the NLC's bounding surfaces. This method is suitable for measuring the response of bent-core liquid crystals, which are expected to demonstrate a much larger flexoelectric effect than traditional, calamitic liquid crystals. Our results reveal that not only is the bend flexoelectric coefficient of bent-core NLCs gigantic (more than 3 orders of magnitude larger than in calamitics) but also it is much larger than would be expected from microscopic models based on molecular geometry. Thus, bent-core nematic materials can form the basis of a technological breakthrough for conversion between mechanical and electrical energy. PMID:17155363

  4. 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.

  5. 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

  6. 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

  7. 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.

  8. 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

  9. 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.

  10. The Discharge Characteristics of TLE-Producing Lightning

    NASA Astrophysics Data System (ADS)

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

    2013-09-01

    On 2 August 2010 and from a site located at the southern tip of Taiwan, we observed 51 TLEs over a thunderstorm near Luzon Island which featured abundant negative cloud-to-ground (-CG) lightning. The TLE events include 42 negative elves, 7 negative halos, 3 positive sprites, and 1 negative cloud-toionosphere (-CI; TYPE I) gigantic jet. The ULF and VLF band sferics of these TLEs were also recorded by radio stations in Taiwan. The radio waveforms of the TLE-associated lightning discharges appear to show dependence on the type of TLEs. For example, the ratio of the peak magnetic field in ULF and VLF bands appear to vary with the type of TLEs. Also based on the observed sferics, we try to find the discharge waveform for the lightning that will induce TLEs.

  11. 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.

  12. Coordinated TLE Campaign using ISUAL and NCKU ULF, ELF/VLF Stations

    NASA Astrophysics Data System (ADS)

    Huang, S.-M.; Lee, L. J.; Chou, J. K.; Chang, S. C.; Chen, A. B.; Su, H. T.; Hsu, R. R.; Kuo, C. L.; Frey, H. U.; Takahashi, Y.; Lee, L. C.

    2013-09-01

    Imager of Sprites and Upper Atmospheric Lightning (ISUAL in short) payload on the FORMOSAT-2 satellite and two ULF and ELF/VLF radio band recording stations in Taiwan are used to further study the characteristics and the correlation between transient luminous events (TLEs) and their associated sferics. From June 2009 to June 2012, 7,276 elves, 733 sprites, 415 halos, 1,671 blue jets, and 22 gigantic jets (GJs) were recorded by ISUAL. More than 50% of these TLEs were found to have corresponding sferics. In all, ~0.5% of sprite-inducing lightning and 80% of halo-inducing lightning are inferred to be generated by negative discharges. However, in sharp contrast to previous studies, this work found that more than 90% of elves are induced by negative lightning.

  13. 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.

  14. 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

  15. Parasitic castration: a perspective from a model of dynamic energy budgets.

    PubMed

    Hall, Spencer R; Becker, Claes; Cáceres, Carla E

    2007-08-01

    Models of the evolution of virulence have typically focused on increased mortality, one of two negative effects that parasites can inflict on their host. Those that consider the other effect, fecundity reduction, can predict that parasites should completely sterilize their hosts. Although this prediction seems extreme, sterilization features prominently in a fascinating strategy, parasitic castration. Such castration can be accompanied by gigantism (unusually large growth of infected hosts), long infectious periods, and fecundity compensation (where, before heavy parasite burdens ensue, newly infected hosts reproduce earlier/more than they would if not infected). Using a model of dynamic energy budgets (DEB), we show how these results readily emerge, assuming that parasites consume energy reserves of the host. The simple, but mechanistic, DEB model follows energy flow though hosts and parasites, starting with ingestion, and continuing with storage of assimilated energy, and use of those reserves for growth and reproduction, as allocated by the host according to the "κ-rule". Using this model, we compare and contrast two strategies for parasites. "Consumers" only steal energy from their hosts, thereby indirectly altering allocation of energy to growth and reproduction, reducing fecundity, and enhancing mortality. "Castrators" steal energy but also directly modify the scheme by which hosts allocate reserve energy, shunting resources from reproduction to growth. Not surprisingly, the model predicts that this strategy should promote gigantism, but it also forecasts longer infectious periods and fecundity compensation. Thus, commonly observed characteristics of parasitic castration readily emerge from a mechanistic model of energy flow using a minimal number of assumptions. Finally, the DEB model for both "consumers" and "castrators" highlight that variation in resources supplied to hosts promotes variation in virulence in a given host-parasite system, holding all else equal. Such predictions highlight the potential importance of resource ecology for virulence in disease systems. PMID:21672839

  16. 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 and provides a proper basis for future molecular biogeographic studies in millipedes and soil organisms from Madagascar. PMID:20813191

  17. On the Formation of the Dabashan Orocline, Central China: Evidence from Seismic Ambient Noise Tomography

    NASA Astrophysics Data System (ADS)

    Jiang, C.; Yang, Y.; Zheng, Y.

    2014-12-01

    The gigantic Dabashan orocline, situated in the south Qinling Orogen, is a response of the tectonic uplift to the collision between the North China Craton and the Yangtze Craton in Mesozoic. However, how the orocline formed and deformed is still not well understood mainly due to inaccessible deep crust structures. In this study, we aim to address this question by investigating the detailed crust structures. We process continuous ambient noise data collected from ~170 stations of Chinese provincial networks operating during 2007 and 2009 to extract interstation surface wave dispersion curves. Using these dispersion curves, we generate Rayleigh wave phase velocity maps at 6-60 sec periods. By inverting the resulting Rayleigh wave dispersion maps using a Bayesian Monte Carlo method, we construct a 3D isotropic Vsv model with a lateral resolution of 50-60 km. The 3D Vsv model reveals detailed crust velocity structures which help to decipher the formation mechanism of the Dabashan orocline. Prominent low velocities are observed beneath the Dabashan orocline at 10-15 km depth, which may represent the buried passive continental margin sedimentations of the Yangtze Craton. High velocities are observed on the two sides of the orocline beneath the Shengnongjia-Huangling and Hannan Domes extending from the surface with Archean-aged outcrops to the mid/lower crust. The deep-rooted high-velocity domes very likely reflect the presence of the relative rigid Archean basement which acts as obstacles during the intra-continental shortening; while detachments may develop in the weak passive continental margin of sedimentations beneath the Dabashan during the shortening process, assisting the southward thrusting of nappes from the south Qinling Orogen onto the northern margin of the Yangtze Craton, which finally forms the gigantic Dabashan orocline. This model is also consistent with the thermo-chronological constraints and stratigraphic records which together indicate the initiation of the uplifts in the two domes are possibly earlier than in Dabashan.

  18. 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

  19. Atmospheric oxygen concentration controls the size history of foraminifers

    NASA Astrophysics Data System (ADS)

    Payne, J.; Jost, A. B.; Ouyang, X.; Skotheim, J. M.; Wang, S. C.

    2010-12-01

    Body size correlates with numerous physiological traits and thus influences organism fitness. However, long-term controls on size evolution remain poorly understood because few datasets spans sufficiently long intervals. One proposed controlling factor is variation in atmospheric oxygen, which is widely argued to have influenced size evolution in numerous taxa, notably gigantism in arthropods during the late Paleozoic. In this study, we compiled a comprehensive genus- and species-level size database of foraminifers (marine protists) to enable an extensive analysis of factors influencing size evolution. Foraminifers are an ideal study group because they are present in all Phanerozoic periods and have been diverse and abundant in shallow-marine habitats since Devonian time. We observe significant correlation between foraminiferan size and atmospheric oxygen concentration in foraminifers as a whole and in half of the major subclades. Larger size is associated with higher oxygen concentrations, as predicted by simple physiological models based on changes in the ratio of surface area to volume. Because the oxygen content ocean waters is controlled in part by atmospheric pO2, we interpret the association between foraminiferan size and pO2 to result from a direct physiological effect of oxygen availability. Atmospheric oxygen concentration predicts foraminiferan size better than six other Phanerozoic time series (pCO2, sea level, number of named geological formations, δ18O, δ13C, 87Sr/86Sr), further suggesting the correlation between oxygen and size does not occur simply through some common geological cause that influences many aspects of Earth system history. These findings support the hypothesis that widespread Permo-Carboniferous gigantism was enabled by high pO2 and suggest that oxygen availability has been among the most important influences on size evolution through Phanerozoic time.

  20. 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

  1. Physical characteristics of TLEs inferred from ISUAL observations (Invited)

    NASA Astrophysics Data System (ADS)

    Kuo, C.; Chen, A. B.; Su, H.; Hsu, R.; Frey, H. U.; Mende, S. B.; Takahashi, Y.; Lee, L.

    2010-12-01

    ISUAL/FORMOSAT-2 is the first satellite mission for the long term survey of upper atmospheric transient luminous phenomena/events (TLEs). The payload consists of three sensor packages including an intensified CCD imager, a six-channel spectrophotometer and a dual-band array photometer. Hence ISUAL experiment could provide information to understand the spatial and the temporal evolutions of TLEs. In this presentation, we will review the important findings of the ISUAL mission in the first five years of operation; mainly on the electric field of sprites streamers [Pasko, 2004; Kuo et al., 2005; Liu et al., 2006; Adachi et al., 2006; Liu et al, 2010; Celestin and Pasko, 2010], the FUV emissions of elves [Mende et al., 2005; Chang et al., 2010], the luminous and electric properties of gigantic jets [Su et al., 2005; Kuo et al., 2009; Chou et al., 2010], and the high-altitude sprite current and the lightning continuing current [Cummer et al, 2006; Adachi et al, 2009]. ISUAL has carried out 762 nm-filtered, 557.7 nm-filtered and 427.8 nm-filtered imager campaigns, besides the regular 1PN2 emission survey. For the 762 nm-filtered imager campaign, a weak but detectable O2 Atmospheric band emission (~1 kR) was predicted based on a plasma chemistry model [Sentman et al., 2008], and the image data may have confirmed the existence of this band emission. While, no significant 557.7 nm emissions were detected from the ISUAL recorded elves. In the 427.8 nm campaign, altitudinal ionization profile of sprites was inferred. The ionization structure of elves and the leader structure of gigantic jets will also be discussed.

  2. Lightning channels emerging from the top of thunderstorm clouds

    NASA Astrophysics Data System (ADS)

    van der Velde, Oscar; Montanyà, Joan; Soula, Serge; Pineda, Nicolau

    2013-04-01

    In recent years, research of transient luminous events is shifting from the rather common elves and sprites high above thunderclouds to the much less frequently observed phenomena issued by the storm cloud itself: gigantic jets (GJ) connecting to the ionosphere, and high-energy terrestrial gamma-ray flashes (TGFs) recorded at spacecraft. These phenomena both are observed more often at tropical latitudes, and a link may or may not exist between the two. It is likely that both share the requirement of high-altitude leaders of negative polarity, which in the case of a GJ escapes from the cloud top and transforms into a long streamer discharge. While this should be easier at lower air densities (higher altitude), previous studies showed that GJs need not be produced by storms with the highest tops. TGFs have still unclear origins, but may be related to production in negative leaders or other regions with strong vertically directed electric fields by runaway electron mechnisms. In December 2009, a gigantic jet was observed in the Mediterranean Sea region. During the same night, a nearby storm produced repeatedly multiple leaders piercing through the cloud top, without any sign of streamers reaching higher altitudes (unlike jets or starters). Similar observations of upward cloud-to-air lightning have been obtained recently by low-light cameras over storms near the Catalonian coast in different seasons. The production conditions are currently being investigated, with a focus on optically determined altitudes of lightning and evolution of storm tops (and their temperature level). The initial impression is that cloud flashes escape into the air above during stages when the growing convective cloud top is very close to the main charge production region. Upward cloud-to-air lightning has also been mapped by the Ebro Lightning Mapping Array, exhibiting inverse bolt-from-the blue characteristics, and as a by-product of a bolt-from-the-blue lightning strike to ground, recorded by a high-speed camera.

  3. 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 observers, alongside the electronic sensors. This factor is essential for the continuity and the homogeneity of historical series and it distinguishes the observatory from a normal weather station. The data collected is published annually in the "Osservazioni meteoriche" magazine, a publication edited by CGEB as a supplement to the scientific journal "Atti e memorie", which is sent to various Public Authorities, Scientific Organizations, libraries and anyone who applies for it.

  4. The kinematics and initiation mechanisms of the earthquake-triggered Daguangbao landslide

    NASA Astrophysics Data System (ADS)

    Yang, Che-Ming; Cheng, Hui-Yun; Tsao, Chia-Che; Wu, Wen-Jie; Dong, Jia-Jyun; Lee, Chyi-Tyi; Lin, Ming-Lang; Zhang, Wei-Fong; Pei, Xiang-Jun; Wang, Gong-Hui; Huang, Run-Qiu

    2015-04-01

    The Daguangbao (DGB) landslide is one of the largest earthquake-triggered landslides induced by the 2008 Wenchuan earthquake in the world over the past century. Based on remote sensing images, topography analysis and field investigation, this landslide was speculated a gigantic atypical wedge failure with the folded bedding plane and a zigzag stepping-out joint system, which outcropped at the south and north, respectively. With the inferred failure surfaces, the volume of the DGB landslide is about 1,051 Mm3. The frequently adopted Rigid Wedge Method (RWM), which assumed zero shear stress on the sliding surface along the vectors perpendicular to the intersection line when evaluating the wedge stability, could not be valid for this super large DGB wedge. Under an assumption that the shear strength is fully mobilized on the sliding surface along the vectors perpendicular to the intersection line, this study proposed to use a Maximum Shear Stress Method (MSSM) to calculate the factor of safety (FOS) of the DGB wedge. Based on the assumptions of the two methods, the FOS of the RWM and MSSM are the upper and lower bounds for the wedge stability analysis. Based on the rotary shear tests, the averaged friction coefficients of the representative materials of the two sliding surfaces are 0.79 (bedding parallel fault gauges) and 0.71 (dolomite joints). Without external force, the FOSs of the DGB landslide are 4.14 and 2.51 by the RWM and MSSM, respectively. Restate, the wedge is stable before the 2008 Wenchuan earthquake. However, DGB landslide can be triggered at 35.7 sec based on the ground acceleration records of strong motion station MZQP during the 2008 Wenchuan earthquake and the pseudo-static stability analysis incorporated into MSSM (Acceleration: EW=0.272g, NS=0.152g, Vertical=0.244g). Moreover, using the friction coefficient of the representative materials under large shear displacement under shear velocity of 1.3 m/s (0.16 for bedding parallel fault gouges and 0.1 for dolomite joints), the gigantic wedge can be speeded up to a maximum velocity of 54 m/sec. The traveled time will be 70 seconds with a travel distance of 1.9 km.

  5. 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 that are related to graded differences in area over what are otherwise similar bioclimatic conditions. We hypothesize that in this system shifts to larger prey, episodic saturation and depression of primary prey density, and predator release may have led to insular gigantism, and that shifts to smaller prey and increased reproductive efficiency in the presence of intense intraspecific competition may have led to insular dwarfism. PMID:20209105

  6. 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 quality signal recordings and allows for precise calculations of the charge moments of upward discharges and strong cloud-to-ground discharges originating from distant sources. The same data is used for Schumann resonance observation. We demonstrate the use of our methods based on recent recordings from the Hylaty ELF station. We include examples of GJ (Gigantic Jet) and TGF (Terrestrial Gamma-ray Flash) related discharges.

  7. Evidence of cumulative offset along the inland Itozawa fault possibly triggered by the past M9 Tohoku, Japan, megathrust earthquakes revealed from a borehole survey

    NASA Astrophysics Data System (ADS)

    Niwa, Y.; Toda, S.; Omata, M.; Mori, Y.

    2013-12-01

    The gigantic Mw 9.0 11 March 2011 Tohoku earthquake suddenly changed the overriding inland area from a compressional stress to an extensional stress regime and then triggered massive seismic swarms in the coastal Fukushima region. The Fukushima-ken-hamadori earthquake on 11 April 2011 (hereinafter, Iwaki earthquake), which was the largest inland off-fault aftershock of the Tohoku earthquake, ruptured the two previously mapped normal faults, the Yunodake fault and the Itozawa fault (Toda and Tsutsumi, BSSA, 2013). The Iwaki earthquake implies that the past gigantic megathrust earthquakes, if they exist, might have frequently triggered slip on similar normal faults including the Itozawa and Yunodake faults themselves. Ideally, collecting all the paleoseismic records from all the normal faults would give us the history of the past M9 class megathrust events and an average inter-event time. Among the series of surveys including paleoseismic trenches (e.g., Toda and Tsutsumi, 2013), we conducted a borehole survey across the central part of the Itozawa fault (Shionohira, Iwaki City), where the maximum vertical displacement 2.1 m was measured. In both upthrown and downthrown sides, extracted core samples expose bedrock conglomerate, fluvial sand and gravel deposits, and artificial fill, from lower to upper, in ascending order. Only in downthrown side, an organic-rich fine layer overlays fluvial deposit, indicating environmental changes from river channel to marsh or pond. We found evidence for cumulative vertical displacement on the top of pre-2011 artificial fill (1.7 m), river channel gravel layer (2.5 m), and bedrock (3.4 m). On the basis of sudden environmental changes from river to pond observed after the Iwaki earthquake due to subsided upstream area (Toda and Tsutsumi, 2013), we interpret that change in sedimentary facies from fluvial gravel to marsh or pond organic layer in the downthrown side corresponds to one of the past surface-rupturing earthquakes. Radiocarbon age yielded from the organic-rich unit suggests that one of the pre-2011 surface rupturing earthquakes occurred about 50,000 years ago. The amount of vertical displacement at one of the pre-2011 earthquakes (ca. 0.8 m) is significantly smaller than displacement at the Iwaki earthquake. Together with large coseismic slip at the 2011 event, it implies that the characteristic earthquake model cannot be simply applied to the faults largely influenced or directly triggered by huge megathrust earthquakes nearby.

  8. 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)

  9. 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

  10. 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.

  11. Land subsidence of clay deposits after the Tohoku-Pacific Ocean Earthquake

    NASA Astrophysics Data System (ADS)

    Yasuhara, K.; Kazama, M.

    2015-11-01

    Extensive infrastructure collapse resulted from the cataclysmic earthquake that struck off the eastern coast of Japan on 11 March 2011 and from its consequent gigantic tsunami, affecting not only the Tohoku region but also the Kanto region. Among the geological and geotechnical processes observed, land subsidence occurring in both coastal and inland areas and from Tohoku to Kanto is an extremely important issue that must be examined carefully. This land subsidence is classifiable into three categories: (i) land sinking along the coastal areas because of tectonic movements, (ii) settlement of sandy deposits followed by liquefaction, and (iii) long-term post-earthquake recompression settlement in soft clay caused by dissipation of excess pore pressure. This paper describes two case histories of post-earthquake settlement of clay deposits from among the three categories of ground sinking and land subsidence because such settlement has been frequently overlooked in numerous earlier earthquakes. Particularly, an attempt is made to propose a methodology for predicting such settlement and for formulating remedial or responsive measures to mitigate damage from such settlement.

  12. 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.

  13. Competition and constraint drove Cope's rule in the evolution of giant flying reptiles

    PubMed Central

    Benson, Roger B. J.; Frigot, Rachel A.; Goswami, Anjali; Andres, Brian; Butler, Richard J.

    2014-01-01

    The pterosaurs, Mesozoic flying reptiles, attained wingspans of more than 10 m that greatly exceed the largest birds and challenge our understanding of size limits in flying animals. Pterosaurs have been used to illustrate Cope’s rule, the influential generalization that evolutionary lineages trend to increasingly large body sizes. However, unambiguous examples of Cope’s rule operating on extended timescales in large clades remain elusive, and the phylogenetic pattern and possible drivers of pterosaur gigantism are uncertain. Here we show 70 million years of highly constrained early evolution, followed by almost 80 million years of sustained, multi-lineage body size increases in pterosaurs. These results are supported by maximum-likelihood modelling of a comprehensive new pterosaur data set. The transition between these macroevolutionary regimes is coincident with the Early Cretaceous adaptive radiation of birds, supporting controversial hypotheses of bird–pterosaur competition, and suggesting that evolutionary competition can act as a macroevolutionary driver on extended geological timescales. PMID:24694584

  14. Emissions of VOCs at urban petrol retail distribution centres in India (Delhi and Mumbai).

    PubMed

    Srivastava, Anjali; Joseph, A E; More, Ajit; Patil, Sunil

    2005-10-01

    Air pollution has assumed gigantic proportion killing almost half a million Asians every year. Urban pollution mainly comprises of emissions from buses, trucks, motorcycle other forms of motorized transport and its supporting activities. As Asia's cities continue to expand the number of vehicles have risen resulting in greater pollution. Fugitive emissions from retail distribution center in urban area constitute a major source. Petrol vapours escape during refueling adding pollutants like benzene, toluene, ethylbenzene and xylene to ambient air. This paper discusses a study on fugitive emissions of Volatile Organic Compounds (VOC) at some refueling station in two metropolitan cities of India, i.e., Mumbai and Delhi. Concentration of VOCs in ambient air at petrol retail distribution center is estimated by using TO-17 method. Concentration of benzene in ambient air in Delhi clearly shows the effect of intervention in use of petroleum and diesel fuel and shift to CNG. Chemical Mass Balance (CMB) model is used to estimate source contributions. At Delhi besides diesel combustion engines, refueling emissions are also major sources. At Mumbai evaporative emissions are found to contribute maximum to Total VOC (TVOC) concentration in ambient air. PMID:16240200

  15. 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

  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. 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

  18. 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

  19. 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

  20. 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.

  1. A new case of Beckwith-Wiedemann syndrome with an 11p15 duplication of paternal origin [46,XY,-21,+der(21), t(11;21)(p15.2;q22.3)pat].

    PubMed

    Krajewska-Walasek, M; Gutkowska, A; Mospinek-Krasnopolska, M; Chrzanowska, K

    1996-01-01

    We present a new case of 11p15 duplication (trisomy 11p15) in a boy (46,XY,-21,+der(21), t(11;21)(p15.2;q22.3)] suffering from Beckwith-Wiedemann syndrome (BWS), whose phenotypically normal father carries a balanced translocation between chromosomes 11 and 21[46,XY, t(11;21)(p15.2;q22.3)]. The paternal grandmother has the same balanced translocation and is also clinically normal. BWS was suspected when the boy was 6 months old because of gigantism, macroglossia, visceromegaly, ear lobe creases and abdominal distention. Apart from the characteristic BWS phenotype, the boy has other features which are almost exclusively observed in 11p trisomy (high forehead with frontal upsweep of hair, wide central nose bridge, slightly beaked nose, chubby cheeks and severe mental retardation). So far, at least eight cases of 11p15 duplication have been described as patients with BWS. In six of these, the duplication was due to inheritance of a translocated or rearranged paternal chromosome. This was also the case in our patient. In the two other previously published cases, the 11p15 duplications were de novo, but in one of these, DNA analysis has subsequently shown that the duplication was of paternal origin. We discuss our observations in relation to the above-mentioned previous cases of 11p15 duplication and the possible role of genomic imprinting in the etiology of BWS. PMID:8872040

  2. 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

  3. McCune Albright syndrome in association with excessive GH secretion: case report.

    PubMed

    zsu, Elif; Mutlu, Gl Ye?iltepe; izmecio?lu, Filiz Mine; Hatun, ?kr

    2015-06-01

    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 caf 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), caf au lait spots, growht hormone levels which could not be supressed with oral glucose tolerance test and increased prolactin levels. PMID:26265896

  4. Thermal expansion anomaly regulated by entropy.

    PubMed

    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

  5. Thermal Expansion Anomaly Regulated by Entropy

    NASA Astrophysics Data System (ADS)

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

    2014-11-01

    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.

  6. "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

  7. Food industry and economic development in the Asia Pacific.

    PubMed

    McKay, John

    2007-01-01

    The food industry in the Asia Pacific region is gigantic in size, and is therefore a key element in the economic development prospects for the region. It is estimated that in 2000, for example, total expenditure on food and beverages in China was worth $US 188.5 billion, second only to that in Japan at $322 billion. Yet it is clear that given the expansion of both populations and incomes in the region this market will expand rapidly over the next few years. Particularly important will be the continued growth of cities and of the share of employment in industrial and service activities. Much of this growth in food purchases will be supplied from local sources, but this will demand some fundamental changes in domestic food production systems. There will also be a substantial growth in the food trade, with ever increasing levels of national and regional specialisation. These developments will put increasing pressures on quality standards at all levels, with a growing emphasis on food safety, integrity, quality, and nutritional and health impacts. This paper reviews the current status of the food industry and the food trade in the region, and presents some projections for future developments. Particular emphasis is given to policy choices that must be made to ensure that the food system in the region develops in ways that are sustainable and most beneficial to the population as a whole. PMID:17392081

  8. 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.

  9. Promises and challenges in solid-state lighting

    NASA Astrophysics Data System (ADS)

    Schubert, Fred

    2010-03-01

    Lighting technologies based on semiconductor light-emitting diodes (LEDs) offer unprecedented promises that include three major benefits: (i) Gigantic energy savings enabled by efficient conversion of electrical energy to optical energy; (ii) Substantial positive contributions to sustainability through reduced emissions of global-warming gases, acid-rain gases, and toxic substances such as mercury; and (iii) The creation of new paradigms in lighting driven by the unique controllability of solid-state lighting sources. Due to the powerful nature of these benefits, the transition from conventional lighting sources to solid-state lighting is virtually assured. This presentation will illustrate the new world of lighting and illustrate the pervasive changes to be expected in lighting, displays, communications, and biotechnology. The presentation will also address the formidable challenges that must be addressed to continue the further advancement of solid-state lighting technology. These challenges offer opportunities for research and innovation. Specific challenges include light management, carrier transport, and optical design. We will present some innovative approaches in order to solve known technical challenges faced by solid-state lighting. These approaches include the demonstration and use of new optical thin-film materials with a continuously tunable refractive index. These approaches also include the use of polarization-matched structures that reduce the polarization fields in GaInN LEDs and the hotly debated efficiency droop, that is, the decreasing LED efficiency at high currents.

  10. 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.

  11. 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

  12. 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.

  13. Software implementation of the SKIPSM paradigm under PIP

    NASA Astrophysics Data System (ADS)

    Hack, Ralf; Waltz, Frederick M.; Batchelor, Bruce G.

    1997-09-01

    SKIPSM (separated-kernel image processing using finite state machines) is a technique for implementing large-kernel binary- morphology operators and many other operations. While earlier papers on SKIPSM concentrated mainly on implementations using pipelined hardware, there is considerable scope for achieving major speed improvements in software systems. Using identical control software, one-pass binary erosion and dilation structuring elements (SEs) ranging from the trivial (3 by 3) to the gigantic (51 by 51, or even larger), are readily available. Processing speed is independent of the size of the SE, making the SKIPSM approach practical for work with very large SEs on ordinary desktop computers. PIP (prolog image processing) is an interactive machine vision prototyping environment developed at the University of Wales Cardiff. It consists of a large number of image processing operators embedded within the standard AI language Prolog. This paper describes the SKIPSM implementation of binary morphology operators within PIP. A large set of binary erosion and dilation operations (circles, squares, diamonds, octagons, etc.) is available to the user through a command-line driven dialogue, via pull-down menus, or incorporated into standard (Prolog) programs. Little has been done thus far to optimize speed on this first software implementation of SKIPSM. Nevertheless, the results are impressive. The paper describes sample applications and presents timing figures. Readers have the opportunity to try out these operations on demonstration software written by the University of Wales, or via their WWW home page at http://bruce.cs.cf.ac.uk/bruce/index.html .

  14. 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.

  15. On 3D detection of lightning discharges and associated events with a small scale interferometric network of radio receivers

    NASA Astrophysics Data System (ADS)

    Mezentsev, A.; Fullekrug, M.

    2012-04-01

    Lightning discharges cause different phenomena in the atmosphere such as sprites, gigantic jets and runaway electron beams. Lightning discharges and their associated events exhibit characteristic electromagnetic signatures in a wide range of frequencies. These electromagnetic signatures are detected and recorded with radio receivers for a detailed investigation. This work uses a small scale network of wide band digital radio receivers, which record vertical electric field strengths in the frequency range from ~ 4 Hz to ~ 400 KHz, with a sampling frequency of 1 MHz, an amplitude resolution of ~ 35 μV/m and a timing accuracy of ~ 12 ns. The small scale interferometric network consists of eight radio receivers, which are separated by distances ranging from 1 km up to 30 km. The network was deployed in Southern France from July to September 2011. Three additional receivers served as remote reference measurements at distances from 300 km up to 1000 km. The small scale interferometric network enables the detection of lightning discharges and associated events in three dimensions for nearby thunderstorms which are less than 500 km away. The network operated successfully during several nearby sprite producing thunderstorms. The recorded waveforms are very consistent and exhibit small time delays which reflect the propagation of the electromagnetic waves across the network. These time delays are used to determine the bearing and elevation angle of the arriving electromagnetic energy. The first results obtained with the interferometric network are presented.

  16. Monitoring the lower ionosphere with a small scale interferometric network of radio receivers

    NASA Astrophysics Data System (ADS)

    Mezentsev, Andrey; Fullekrug, Martin

    2013-04-01

    Sprites, gigantic jets and relativistic electron beams above thunderclouds attracted significant attention in the last decades. These natural transient events are caused by lightning discharges and they are associated with characteristic low frequency radio emissions from a certain height above thunderclouds. The altitudes of these sources can be inferred from their radio waves which are reflected by the lower ionosphere along their propagation path. The ionospheric conditions vary with time and location which makes it important to monitor the lower ionosphere during the observation period. This work uses 100 kHz radio emissions from the LOng Range Navigation (LORAN) transmitters in Western Europe to monitor the height of the reflecting lower ionosphere. The pulsed LORAN transmissions are synced with high precision to atomic time and they are therefore particularly suitable for monitoring the lower ionosphere. The vertical electric field strengths of the LORAN transmissions are recorded with a small scale interferometric network of eight wide band digital radio receivers which are separated by distances ranging from ~3 km up to ~30 km. The network was deployed in southern France during the summer months from July to September in 2011 and 2012 when numerous thunderstorms occur. The ionospheric monitoring with the network reveals the dynamics of the lower ionosphere at different locations throughout the observation period. Results of the ionospheric monitoring for different meteorological conditions will be presented.

  17. Anomalous surface lattice dynamics in the low-temperature phase of Ba(Fe1−xCox)2As2

    PubMed Central

    Teng, Jing; Chen, Chen; Xiong, Yimin; Zhang, Jiandi; Jin, Rongying; Plummer, E. W.

    2013-01-01

    In complex materials, how correlation between charge, spin, and lattice affects the emergent phenomena remains unclear. The newly discovered iron-based high-temperature superconductors and related compounds present to the community a prototype family of materials, where interplay between charge, spin, and lattice degrees of freedom can be explored. With the occurrence of structural, magnetic, and superconducting transitions in the bulk of these materials, creating a surface will change the delicate balance between these phases, resulting in new behavior. A surface lattice dynamics study on (001) Ba(Fe1−xCox)2As2, through electron energy loss spectroscopy measurements, reveals unusual temperature dependence of both the phonon frequency and line width in the low-temperature orthorhombic phase. The rate of change of phonon frequency with temperature is gigantic, two orders of magnitude larger than in the bulk. This behavior cannot be explained using conventional models of anharmonicity or electron–phonon coupling; instead, it requires that a large surface-spin-charge-lattice coupling be included. Furthermore, the higher surface-phase-transition temperature driven by surface stabilization of the low-temperature orthorhombic phase seems to turn the first-order transition (bulk) into the second-order type, equivalent to what is observed in the bulk by applying a uniaxial pressure. Such equivalence indicates that the surface mirrors the bulk under extreme conditions. PMID:23284168

  18. Meteorological aspects of elves and jets

    NASA Astrophysics Data System (ADS)

    Chen, A. B.; Tsai, L.; Lee, L.; Chou, J.; Su, H.; Hsu, R.; Wu, C.; Lin, P.; Mende, S. B.; Frey, H. U.; Takahashi, Y.; Lee, L.

    2008-12-01

    Evidence for ocean-atmosphere-ionosphere coupling is revealed in recent studies of ISUAL transient luminous events (TLEs) [Chen et al., 2008]. The results suggest that the meteorological systems below the stratosphere, primarily driven by sea surface temperature and solar radiation, play essential roles in inducing TLEs between the cloud top and the lower ionosphere. Through analyzing the ISUAL-recorded TLEs since July 2004, we realize that different types of TLEs are likely associated with different meteorological systems. For example, the elves are mainly located above Intertropical Convergence Zone (ITCZ) and South Pacific Convergence Zone (SPCZ); elves also are strongly correlated with the atmospheric updraft and the precipitation. The fall/winter elves distribute along storm tracks poleward of 30 degrees north or south, implying their association with extratropical cyclones. Numerous blue jets and gigantic jets are recorded around tropical cyclones by ISUAL. Several recent examples indicate that blue jets and lightning often occur in rapid successions in the strong convective regions associated with the spiral rainbands of typhoons or hurricanes. Illustrative data and some of the probable mechanisms will be presented in the conference.

  19. TLEs, ITCZ, Storm Tracks and Their Correlation

    NASA Astrophysics Data System (ADS)

    Lee, L.; Chen, A. B.; Tsai, L.; Chou, J.; Chang, S.; Kuo, C.; Su, H.; Hsu, R.; Wu, C.; Lin, P.; Lee, L.

    2008-12-01

    Between July 2004 and February 2008, ISUAL has recorded 6747 elves, 718 sprites, 783 halos, 1081 blue jets, and 17 gigantic jets. We examine the correlation between the distribution of TLEs and the annual Inter- tropical Convergence Zone (ITCZ) distribution by analyzing the outgoing long-wave radiation (OLR) data from NOAA/ESRL Physical Sciences Division. The results indicate that there are two different TLE distribution patterns. For the low latitude region, the movement of TLEs occurrence follows the seasonal migration of the IITCZ. In northern hemisphere summer, the ITCZ is mainly located to the north of the equator and the distribution of TLEs follows. In southern hemisphere summer, part of ITCZ moves to south of the equator and so does the distribution of TLEs. In the middle and high latitude winter regions, the ISUAL recorded TLEs are defined as the winter TLEs, which are generally associated with cold fronts, air masses and mid-latitude cyclones. From the global distribution of winter TLEs, it is shown that they tend to congregate in some specific regions. Namely, in the northern winter , TLEs concentrate over the Japan Sea , north Pacific Ocean , northwest Atlantic Ocean and Mediterranean Sea ; while in the southern winter , TLEs distribute primarily over the south coast of Australia , south Pacific Ocean and east coast of south America. We find the distribution of winter TLEs is well collocated with the storm tracks. The correlation between the winter TLEs and storm tracks is thus analyzed.

  20. 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

  1. 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

  2. Baleen boom and bust: a synthesis of mysticete phylogeny, diversity and disparity.

    PubMed

    Marx, Felix G; Fordyce, R Ewan

    2015-04-01

    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

  3. 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)

  4. Chemical control of downy mildew on lettuce and basil under greenhouse.

    PubMed

    Gullino, M L; Gilardi, G; Garibaldi, A

    2009-01-01

    Eight experimental trials were carried out during 2007 and 2008 to evaluate the efficacy of different fungicides against downy mildew of lettuce (Bremia lactucae) and basil (Peronospora belbahrii) under greenhouse conditions, at temperatures ranging from 19 to 24 degrees C. The mixture fluopicolide (fungicide belonging to the + propamocarb hydrochloride (fungicide belonging to the new chemical class of acyl-picolides) was compared with metalaxyl m + copper, zoxamide + mancozeb, iprovalicarb + Cu, fenamidone + fosetyl-Al and azoxystrobin. Two treatments were carried out at 8-12 day interval on lettuce and basil. The artificial inoculation of B. lactucae on lettuce (cv Cobham Green) and P. belbahrii. on basil (cv Genovese gigante) was carried out by using 1 x 10(5) CFU/ml 24 h after the first treatment. In the presence of a medium-high disease severity, all fungicides tested in these trials were effective against downy mildew on lettuce and basil as the other fungicides already available. The importance of the availability of a number of different chemicals to control downy mildews is discussed. PMID:20222581

  5. Chemical control of downy mildew on lettuce and basil under greenhouse.

    TOXLINE Toxicology Bibliographic Information

    Gullino ML; Gilardi G; Garibaldi A

    2009-01-01

    Eight experimental trials were carried out during 2007 and 2008 to evaluate the efficacy of different fungicides against downy mildew of lettuce (Bremia lactucae) and basil (Peronospora belbahrii) under greenhouse conditions, at temperatures ranging from 19 to 24 degrees C. The mixture fluopicolide (fungicide belonging to the + propamocarb hydrochloride (fungicide belonging to the new chemical class of acyl-picolides) was compared with metalaxyl m + copper, zoxamide + mancozeb, iprovalicarb + Cu, fenamidone + fosetyl-Al and azoxystrobin. Two treatments were carried out at 8-12 day interval on lettuce and basil. The artificial inoculation of B. lactucae on lettuce (cv Cobham Green) and P. belbahrii. on basil (cv Genovese gigante) was carried out by using 1 x 10(5) CFU/ml 24 h after the first treatment. In the presence of a medium-high disease severity, all fungicides tested in these trials were effective against downy mildew on lettuce and basil as the other fungicides already available. The importance of the availability of a number of different chemicals to control downy mildews is discussed.

  6. 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

  7. 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

  8. A transparently scalable visualization architecture for exploring the universe.

    PubMed

    Fu, Chi-Wing; Hanson, Andrew J

    2007-01-01

    Modern astronomical instruments produce enormous amounts of three-dimensional data describing the physical Universe. The currently available data sets range from the solar system to nearby stars and portions of the Milky Way Galaxy, including the interstellar medium and some extrasolar planets, and extend out to include galaxies billions of light years away. Because of its gigantic scale and the fact that it is dominated by empty space, modeling and rendering the Universe is very different from modeling and rendering ordinary three-dimensional virtual worlds at human scales. Our purpose is to introduce a comprehensive approach to an architecture solving this visualization problem that encompasses the entire Universe while seeking to be as scale-neutral as possible. One key element is the representation of model-rendering procedures using power scaled coordinates (PSC), along with various PSC-based techniques that we have devised to generalize and optimize the conventional graphics framework to the scale domains of astronomical visualization. Employing this architecture, we have developed an assortment of scale-independent modeling and rendering methods for a large variety of astronomical models, and have demonstrated scale-insensitive interactive visualizations of the physical Universe covering scales ranging from human scale to the Earth, to the solar system, to the Milky Way Galaxy, and to the entire observable Universe. PMID:17093340

  9. Discovery of a rare arboreal forest-dwelling flying reptile (Pterosauria, Pterodactyloidea) from China

    PubMed Central

    Wang, Xiaolin; Kellner, Alexander W. A.; Zhou, Zhonghe; de Almeida Campos, Diogenes

    2008-01-01

    A previously undescribed toothless flying reptile from northeastern China, Nemicolopterus crypticus gen. et sp. nov., was discovered in the lacustrine sediments of the Early Cretaceous Jiufotang Formation, western Liaoning, China. The specimen consists of an almost complete articulated skeleton (IVPP V14377) and, despite representing an immature individual, based on the ossification of the skeleton, it is not a hatchling or newborn, making it one of the smallest pterosaurs known so far (wing span ≈250 mm). It can be distinguished from all other pterosaurs by the presence of a short medial nasal process, an inverted “knife-shaped” deltopectoral crest of the humerus, and the presence of a well developed posterior process on the femur above the articulation with the tibia. It further shows the penultimate phalanges of the foot curved in a degree not reported in any pterosaur before, strongly indicating that it had an arboreal lifestyle, more than any other pterodactyloid pterosaur known so far. It is the sister-group of the Ornithocheiroidea and indicates that derived pterosaurs, including some gigantic forms of the Late Cretaceous with wingspans of >6 m, are closely related to small arboreal toothless creatures that likely were living in the canopies of the ancient forests feeding on insects. PMID:18268340

  10. 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.

  11. 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

  12. Saving a life but losing the patient.

    PubMed

    Greene, Mark

    2013-12-01

    Gregor Samsa awakes to find himself transformed into a gigantic bug. The creature's inchoate flailing leads Gregor's sister to conclude that Gregor is no more, having been replaced by a brute beast lacking any vestige of human understanding. Sadly, real cases of brain injury and disease can lead to psychological metamorphoses so profound that we cannot easily think that the survivor is the person we knew. I argue that there can be cases in which statements like, "It's just not Gregor anymore," are not merely figures of speech. With this in mind, I consider three possible results of saving a biological life: (1) ordinary cases where saving the life will save the person, with strong duties to save the life; (2) cases where the intervention needed to save the life will replace the person, with strong duties not to save the life; (3) cases in which it is indeterminate whether the person will be saved or replaced. How should we think about indeterminate cases? Impersonal ethical considerations miss the point, while standard person-affecting considerations are inapplicable. I suggest turning attention away from survival towards a richer focus on what I call "personal concern." I show how considerations of personal concern, unlike those of self-interest, need not be tied to survival and how this allows personal concern to provide a basis for ethically substantive discussion of cases where saving a life might result in losing the patient. PMID:24293085

  13. Permian alkaline granites in the Erenhot-Hegenshan belt, northern Inner Mongolia, China: Model of generation, time of emplacement and regional tectonic significance

    NASA Astrophysics Data System (ADS)

    Tong, Ying; Jahn, Bor-ming; Wang, Tao; Hong, Da-wei; Smith, Eugene I.; Sun, Min; Gao, Jian-feng; Yang, Qi-di; Huang, Wei

    2015-01-01

    The Central Asian Orogenic Belt (CAOB) is known to be the Earth's largest Phanerozoic accretionary orogenic belt. Its southern margin, particularly in the southern Mongolia and Inner Mongolia (SMIM), shows an extensive distribution of alkaline granites. Study of these granites could shed light on long-debated hypotheses on the late Paleozoic tectonic evolution of this region. In this work, we performed a detailed zircon age determination and whole rock geochemical analysis on alkaline granites from four granitic plutons in northern Inner Mongolia (Hongol, Saiyinwusu, Baolag, and Baiyinwula). U-Pb zircon dating yielded early Permian ages (ca. 280 Ma) for the four plutons. Whole-rock geochemical analyses show chemical characteristics typical of alkaline granites. Coeval alkaline granites from southern Mongolia to northern Inner Mongolia constitute a gigantic (∼900 km) Permian (292-275 Ma) alkaline granite belt in the southern CAOB. Furthermore, these alkaline granites have whole-rock εNd(t) varying between +3.6 and +6.4 and zircon εHf(t) from +4.9 to +20.3. The geochemical and Nd-Hf isotopic signatures suggest derivation by partial melting of a protolith assemblage dominated by metasomatised mantle, and followed by fractional crystallization in a post-collisional extensional environment.

  14. Interlayer coupling in ferroelectric bilayer and superlattice heterostructures.

    PubMed

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

    2006-12-01

    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. A number of experimental studies have shown that these materials have many peculiar properties which 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 theoretical analysis shows that compositional variations across ferroelectric bilayers result in a broken spatial inversion symmetry that can lead to asymmetric thermodynamic potentials favoring one ferroelectric ground state over the other. Furthermore, the thermodynamic modeling indicates that there is a strong electrostatic coupling between the layers that 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. PMID:17186917

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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.

  1. 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

  2. Environmental and biotic controls on the evolutionary history of insect body size

    PubMed Central

    Clapham, Matthew E.; Karr, Jered A.

    2012-01-01

    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. PMID:22665762

  3. Metal enrichment in the Fermi bubbles as a probe of their origin

    NASA Astrophysics Data System (ADS)

    Inoue, Yoshiyuki; Nakashima, Shinya; Tahara, Masaya; Kataoka, Jun; Totani, Tomonori; Fujita, Yutaka; Sofue, Yoshiaki

    2015-06-01

    The Fermi bubbles are gigantic gamma-ray structures in our Galaxy. The physical origin of the bubbles is still under debate. The leading scenarios can be divided into two categories. One is nuclear star-forming activity similar to extragalactic starburst galaxies and the other is past active galactic nucleus (AGN)-like activity of the Galactic center supermassive black hole. In this letter, we propose that metal abundance measurements will provide an important clue to probe their origin. Based on a simple spherically symmetric bubble model, we find that the generated metallicity and abundance patterns of the bubbles' gas strongly depend on assumed star formation or AGN activities. Star formation scenarios predict higher metallicities and abundance ratios of [O/Fe] and [Ne/Fe] than AGN scenarios do because of supernovae ejecta. Furthermore, the resultant abundance depends on the gamma-ray emission process because different mass injection histories are required for the different gamma-ray emission processes due to the acceleration and cooling time scales of non-thermal particles. Future X-ray missions such as ASTRO-H and Athena will give a clue to probe the origin of the bubbles through abundance measurements with their high energy resolution instruments.

  4. Haploinsufficiency of Anx7 tumor suppressor gene and consequent genomic instability promotes tumorigenesis in the Anx7(+/-) mouse

    PubMed Central

    Srivastava, Meera; Montagna, Cristina; Leighton, Ximena; Glasman, Mirta; Naga, Shanmugam; Eidelman, Ofer; Ried, Thomas; Pollard, Harvey B.

    2003-01-01

    Annexin 7 (ANX7) acts as a tumor suppressor gene in prostate cancer, where loss of heterozygosity and reduction of ANX7 protein expression is associated with aggressive metastatic tumors. To investigate the mechanism by which this gene controls tumor development, we have developed an Anx7(+/-) knockout mouse. As hypothesized, the Anx7(+/-) mouse has a cancer-prone phenotype. The emerging tumors express low levels of Anx7 protein. Nonetheless, the wild-type Anx7 allele is detectable in laser-capture microdissection-derived tumor tissue cells. Genome array analysis of hepatocellular carcinoma tissue indicates that the Anx7(+/-) genotype is accompanied by profound reductions of expression of several other tumor suppressor genes, DNA repair genes, and apoptosis-related genes. In situ analysis by tissue imprinting from chromosomes in the primary tumor and spectral karyotyping analysis of derived cell lines identify chromosomal instability and clonal chromosomal aberrations. Furthermore, whereas 23% of the mutant mice develop spontaneous neoplasms, all mice exhibit growth anomalies, including gender-specific gigantism and organomegaly. We conclude that haploinsufficiency of Anx7 expression appears to drive disease progression to cancer because of genomic instability through a discrete signaling pathway involving other tumor suppressor genes, DNA-repair genes, and apoptosis-related genes. PMID:14608035

  5. 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.

  6. Ultrafast Critical Nematic Fluctuations and Giant Magnetoelastic Coupling in Iron Pnictide

    NASA Astrophysics Data System (ADS)

    Patz, Aaron; Li, Tianqi; Ran, Sheng; Fernandes, Rafael; Schmalian, Joerg; Bud'Ko, Sergey; Canfield, Paul; Perakis, Ilias; Wang, Jigang

    2014-03-01

    A ubiquitous anisotropy in the normal state properties of many of the iron pnictides presents a crosscutting challenge important for understanding quantum magnetism and high-temperature superconductivity. Although an electronically-driven nematicity has been invoked, distinguishing this from spin and structural orders is challenging because they all couple together to break the same tetragonal symmetry. Here we use femtosecond-resolved polarimetry to reveal critical fluctuations of nematic correlation in unstrained Ba(Fe1-xCox)2As2. The ultrafast anisotropic response, which arises from the two-fold in-plane anisotropy of the refractive index, displays a characteristic two-step recovery absent in the isotropic response. The fast recovery appears only in the magnetically ordered state, whereas the slow one persists in the paramagnetic phase, with increasing relaxation time, indicative of critical nematic fluctuations approaching the structural transition temperature. The dynamics reveal a gigantic magnetoelastic coupling that far exceeds electron-spin and electron-phonon couplings, opposite to conventional magnetic metals. Supported by the NSF and THALES program NANOPHOS.

  7. 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.

  8. Low-field magnetoelectric effect at room temperature.

    PubMed

    Kitagawa, Yutaro; Hiraoka, Yuji; Honda, Takashi; Ishikura, Taishi; Nakamura, Hiroyuki; Kimura, Tsuyoshi

    2010-10-01

    The discoveries of gigantic ferroelectric polarization in BiFeO(3) (ref. 1) and ferroelectricity accompanied by a magnetic order in TbMnO(3) (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, 28 K in TbMnO(3) (ref. 2) and 230 K 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 Sr(3)Co(2)Fe(24)O(41) 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. PMID:20693994

  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. Kondo Effect of U Impurities in Dilute (YU)2Zn17

    NASA Astrophysics Data System (ADS)

    Takagi, Shigeru; Suzuki, Hiroyuki; Anzai, Kousuke

    2001-10-01

    Extending previous work on single-site properties of U ions in (LaU)2Zn17, we have investigated, from ρ(T), χ(T) and Cp(T) on single crystals, (Y1-xUx)2Zn17 with x=0.025 and 0.050, which has almost the same unit-cell volume as an antiferromagnetic heavy-electron compound U2Zn17. Remarkable features in the dilute-impurity limit have been clarified, which include Kondo behavior of ρ(T), large and almost isotropic χimp(T), and strongly enhanced Cimp(T)/T with gigantic γimp=2.02 2.05 J/K2·mole-U as T→0 due to a low characteristic energy-scale of the system. It is shown that gross features of the data are explained in terms of the conventional Kondo effect in the presence of the crystal field with the U3+ \\varGamma6 doublet ground state. It is also shown that the variation of γ with the unit-cell volume in related systems is not explained as a volume effect on TK and that even the behavior of fictitious “paramagnetic” U2Zn17 is not described as a collection of U impurities in dilute (YU)2Zn17.

  11. 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.

  12. 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?

  13. 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

  14. 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

  15. 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

  16. The implementation of Agenda 21 'our common failure'?

    PubMed

    Langeweg, F

    1998-07-30

    Sustainable development has for a long time been considered the starting-point for environmental policy, with Agenda 21 leading the way to such development. Social and economic equity, as well as global efficiency and development, are considered among the requirements for sustainable development. Only when such development is reached, will the solution to environmental problems come into perspective. Although we are now 5 years along the road marked out by Agenda 21, the perspectives for achieving the objectives stated are still slight. Despite economic growth, global inequity is on the increase. The conversion of natural areas to agricultural land will greatly increase due to the population growth, especially in Asia and Africa. In North America and Europe this trend seems reversed: life expectancy is longer and people's health has improved. The developing world is catching up. However, there is more needed to bring the world population's welfare and social security levels up to par. At the same time the environmental pressures on the world's natural areas will have to be brought down substantially. This can be done using market-based instruments, supplemented where necessary with orders, bans, fiscal measures and agreements at national and international levels. Internationally, a policy directed to investments and trade is needed to stimulate developing regions to undertake technological renewal and work away backlogs. The technological potential is still gigantic, but investment in the social system -- in other words, in people -- will be necessary if we are actually to use this potential. PMID:9753794

  17. 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.

  18. [The army of the East and health services].

    PubMed

    Guivarc'h, Marcel

    2007-01-01

    A medical disaster due to the failure of a plan intended to free Belfort by an army of 90 000 men, formed by Bourbaki in Nevers, joined in Besancon by 40 000 men from Lyon and from Dijon. Envisaged in three days, the regrouping lasts three weeks. A gigantic railway blocking, by an icy cold, leaves in the trains of the soldiers without food, of the horses without irons nor fodder. A third of manpower is from the start inapt for the fights. The utter exhaustion of the men don't make possible to exploit the success of Villersexel's battle (January 9), nor to cross Lizaine. The medical army officers joined those of the civil ambulances formed in South-east, and that of Pamard. The care given with delay on the covered with snow ground, in precarious shelters or encumbered hospitals, is summary. Cold, gelures, walk feet, infection, associated variola, are the cause of a high mortality: 8 500 died, and much of casualties. Ordered by Bourbaki, the dramatic routed to Switzerland by Pontarlier and the Cluse collar, under the Prussian shells will add 15 000 killed. The Swiss ones collect sick and wounded in 200 ambulances along the border, and on 87 000 men to be disarmed in 9 000 hospitalize. Pamard will remain until March 18 at the Pontarlier' hospital. PMID:18175609

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

    PubMed Central

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

    2006-01-01

    Umoonasaurus demoscyllus gen. et sp. nov. is a new small-bodied (approx. 2.5 m) 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° 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

  20. 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.

  1. Discovery of a rare arboreal forest-dwelling flying reptile (Pterosauria, Pterodactyloidea) from China.

    PubMed

    Wang, Xiaolin; Kellner, Alexander W A; Zhou, Zhonghe; Campos, Diogenes de Almeida

    2008-02-12

    A previously undescribed toothless flying reptile from northeastern China, Nemicolopterus crypticus gen. et sp. nov., was discovered in the lacustrine sediments of the Early Cretaceous Jiufotang Formation, western Liaoning, China. The specimen consists of an almost complete articulated skeleton (IVPP V14377) and, despite representing an immature individual, based on the ossification of the skeleton, it is not a hatchling or newborn, making it one of the smallest pterosaurs known so far (wing span approximately 250 mm). It can be distinguished from all other pterosaurs by the presence of a short medial nasal process, an inverted "knife-shaped" deltopectoral crest of the humerus, and the presence of a well developed posterior process on the femur above the articulation with the tibia. It further shows the penultimate phalanges of the foot curved in a degree not reported in any pterosaur before, strongly indicating that it had an arboreal lifestyle, more than any other pterodactyloid pterosaur known so far. It is the sister-group of the Ornithocheiroidea and indicates that derived pterosaurs, including some gigantic forms of the Late Cretaceous with wingspans of >6 m, are closely related to small arboreal toothless creatures that likely were living in the canopies of the ancient forests feeding on insects. PMID:18268340

  2. A new azhdarchid pterosaur from the Late Cretaceous of the Transylvanian Basin, Romania: implications for azhdarchid diversity and distribution.

    PubMed

    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

  3. 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.

  4. 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

  5. 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.

  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. 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.

  8. 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

  9. 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

  10. 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

  11. A numerical challenge on the core-collapse supernovae: physics of neutrino and matter at extreme conditions

    NASA Astrophysics Data System (ADS)

    Sumiyoshi, Kohsuke

    2011-07-01

    Core-collapse supernovae are the explosive phenomena, which occur at the end of the life of massive stars. Despite the importance of these astrophysical events, the mechanism of supernova explosion has been a mystery even after the extensive studies for decades. The unsolved problem involves nuclear and neutrino physics at extreme conditions as well as the hydrodynamical aspects in astrophysics. The physics in femto-meter scale may change drastically the gigantic outcome of the core bounce after the gravitational collapse of the massive stars. In this contribution, I overview recent topics on the numerical challenges to clarify the supernova phenomena. Recent advance of nuclear physics for unstable nuclei and exotic hadrons helps us to provide the nuclear data inside the supernova core. The influence of the dense matter on the explosion and supernova neutrinos has been clarified using the newly constructed data tables based on the theoretical and experimental developments. Recent studies demonstrated that the short neutrino bursts from the black hole formation in more massive stars can be a probe of exotic matter including hyperons and quarks by observations at the neutrino detector facilities. Despite the progress in nuclear and neutrino physics, no explosion is found in the numerical simulations under the spherical symmetry and hence novel effects in multi-dimensions are argued to be essential for the explosion mechanism. Toward the final goal to clarify the supernova mechanism, it is necessary to combine the best knowledge of nuclear, particle physics and astrophysics with computing science on supercomputing facilities.

  12. The first freshwater mosasauroid (Upper Cretaceous, Hungary) and a new clade of basal mosasauroids.

    PubMed

    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

  13. Interference effects in white clover genotypes grown as pure stands and binary mixtures with different grass species and varieties.

    PubMed

    Annicchiarico, P; Piano, E

    1994-05-01

    Six white clover genotypes and eight grass varieties belonging to four different species were grown both in monoculture and as grass-legume binary mixtures in dense swards for two years under a mowing regime and a management including N fertilization. Dry matter yield and yield-related traits were recorded to investigate some aspects of inter-specific interference in white clover-based mixtures and to define a methodology for selecting genotypes of this clover suited to conditions of association. Clover was at a competitive disadvantage in most mixtures. Differences among grasses for aggressiveness were related more to variety vigour than to species. Clover compatibility proved specific only in relation to grass vigour. Variation among clovers for tolerance to competitive stress involved significant cross-over interactions passing from monoculture to severe stress conditions for clover yield and other traits, and was related positively to stolon density and negatively to yield and leaf gigantism traits recorded in monoculture. Clover selection for high levels of competitive stress seems possible either by genotype assessment in stress conditions or by a combination of high yield and stolon density assessed in monoculture. PMID:24185920

  14. 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

  15. 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

  16. 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

  17. 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

  18. The Chandra XRCF Calibration Experience - A Personal Recollection

    NASA Astrophysics Data System (ADS)

    Flanagan, Kathryn

    2013-01-01

    My undergraduate thesis research involved calibrating an imaging proportion counter for the Focal Plane Crystal Spectrometer on the Einstein X-ray Observatory. The testing was done in a laboratory on the 5th floor of MIT’s Center for Space Research, with one or two other people in the room. Years later, when I joined the Chandra project, I had the unique experience of participating in the calibration of the mirrors and detectors at the X-Ray Calibration Facility (XRCF) at the Marshall Space Flight Center in Huntsville Alabama. This was an eye-opening experience of an entirely different magnitude! A quarter-mile long vacuum tube extended from an X-ray source building to a two-story structure housing a gigantic vacuum test chamber. Teams representing every part of the Observatory worked 24 hours a day, seven days a week for nearly half a year. This experience represented an immense milestone - for the Observatory, perhaps for X-ray astronomy, and certainly for the people who worked so hard (and sacrificed so much) to achieve it.

  19. 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.

  20. The aureole of Olympus Mons (Mars) as the compound deposit of submarine landslides

    NASA Astrophysics Data System (ADS)

    De Blasio, Fabio Vittorio

    2011-12-01

    The enigmatic deposits building up the Olympus Mons aureole on Mars are likely among the largest landslide remnants in the Solar System. These deposits exhibit an extraordinary run-out distance (up to nearly 700 km), in spite of a fall height some 100 times smaller. After quantifying the mobility of the Olympus Mons aureole lobes it is suggested, based on dynamical considerations and morphological analysis, that the aureole could be the consequence of a series of gigantic subaqueous landslides. In order to bring evidence in favor of this interpretation, comparisons are drawn between the different landslide deposits on Earth and Mars, emphasizing the similarity with the rock avalanches of the Canary Islands and the Hawaii. The results of experimental subaqueous debris flows are also analyzed, and numerical calculations are introduced to simulate the dynamics of flow. In analogy with certain subaqueous landslides on Earth, it is possible that the outstanding run-out of the aureole lobes was a consequence of hydroplaning, a natural lubrication by water during flow.

  1. 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

  2. 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.

  3. Constraints on early events in Martian history as derived from the cratering record

    SciTech Connect

    Barlow, N.G. )

    1990-08-30

    The shapes and densities of crater size-frequency distribution curves are used to constrain two major events early in Martian history: termination of high obliteration rates and viability of the multiple impact origin of the crustal dichotomy. Distribution curves of fresh craters superposed on uplands, intercrater plains, and ridged plains display shapes and densities indicative of formation prior to the end of heavy bombardment. This observation correlates with other geologic evidence, suggesting a major change in the erosional regime following the last major basin size impact (i.e., Argrye). In addition, the multisloped nature of the curves supports the idea that the downturn in the crater size-frequency distribution curves reflects the size-frequency distribution of the impactors rather than being the result of erosion. The crustal dichotomy formed prior to the heavy bombardment intermediate epoch based on distribution curves of knobby terrain; if the dichotomy resulted from a single gigantic impact, this observation places constraints on when this event happened. An alternate theory for dichotomy formation, the multiple-impact basin idea, is questioned: since distribution curves of large basins as well as heavy bombardment era units are not represented by a {minus}3 differential power law function, this study finds fewer basins missing on Mars compare to the Moon and Mercury than previously reported. The area covered by these missing basins is less than that covered the northern plains.

  4. Prefoldin and Pins synergistically regulate asymmetric division and suppress dedifferentiation.

    PubMed

    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

  5. 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.

  6. 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

  7. Structure of the TPR Domain of AIP: Lack of Client Protein Interaction with the C-Terminal α-7 Helix of the TPR Domain of AIP Is Sufficient for Pituitary Adenoma Predisposition

    PubMed Central

    Morgan, Rhodri M. L.; Hernández-Ramírez, Laura C.; Trivellin, Giampaolo; Zhou, Lihong; Roe, S. Mark; Korbonits, Márta; Prodromou, Chrisostomos

    2012-01-01

    Mutations of the aryl hydrocarbon receptor interacting protein (AIP) have been associated with familial isolated pituitary adenomas predisposing to young-onset acromegaly and gigantism. The precise tumorigenic mechanism is not well understood as AIP interacts with a large number of independent proteins as well as three chaperone systems, HSP90, HSP70 and TOMM20. We have determined the structure of the TPR domain of AIP at high resolution, which has allowed a detailed analysis of how disease-associated mutations impact on the structural integrity of the TPR domain. A subset of C-terminal α-7 helix (Cα-7h) mutations, R304* (nonsense mutation), R304Q, Q307* and R325Q, a known site for AhR and PDE4A5 client-protein interaction, occur beyond those that interact with the conserved MEEVD and EDDVE sequences of HSP90 and TOMM20. These C-terminal AIP mutations appear to only disrupt client-protein binding to the Cα-7h, while chaperone binding remains unaffected, suggesting that failure of client-protein interaction with the Cα-7h is sufficient to predispose to pituitary adenoma. We have also identified a molecular switch in the AIP TPR-domain that allows recognition of both the conserved HSP90 motif, MEEVD, and the equivalent sequence (EDDVE) of TOMM20. PMID:23300914

  8. Familial acromegaly - case study of two sisters with acromegaly.

    PubMed

    Malicka, Joanna; Świrska, Joanna; Nowakowski, Andrzej

    2011-01-01

    In the majority of cases, acromegaly is sporadic. However, it can also occur in a familial setting as a component of MEN-1, MEN-4, Carney complex (CNC) or as the extremely rare syndrome of isolated familial somatotropinoma (IFS), the latter belonging to familial isolated pituitary adenomas (FIPA). The diagnosis of IFS is based on the recognition of acromegaly/gigantism in at least two family members, given that the family is not affected by MEN-1, MEN-4 or CNC. The authors present a case study of two sisters: a 56 year-old patient (case no. 1) and a 61 year-old patient (case no. 2). In both sisters, acromegaly was recognised in the course of pituitary macroadenoma. Neither of the sisters showed features of MEN-1, MEN-4 or Carney complex. The authors suppose that the presented cases are manifestations of IFS. However, this diagnosis has not been confirmed yet because of the poor availability of genetic tests. PMID:22144223

  9. 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.

  10. Micromechanics of the pericellular matrix

    NASA Astrophysics Data System (ADS)

    Curtis, J. E.; Boehm, H.; Schmitz, C. H. J.; Spatz, J. P.

    2006-03-01

    In recent years, much attention has been directed towards the properties and activities of the cell surface. In particular, the coupling of the membrane to the underlying protein polymer network called the actin cortex plays an important role in many events. The other side of the cell surface is less studied, although it too has a bound polymer network comprised of gigantic cross-linked polysaccharides (sugars). Called the pericellular matrix (PCM), it is associated with many cells including fibroblasts, chondrocytes, endothelial and smooth muscle cells. Its thickness can vary from 10's of nanometers to 10 microns and it is associated with adhesion dependent events like migration and mitosis. Biologists often hypothesize that its viscoelastic properties are responsible for the modulation of cell adhesion activities. To investigate this proposal, we measure the PCM's viscoelasticity using microrheology and probe the sharpness of its edge and its mesh size. The elastic modulus of the PCM under different condition is determined, and we characterize the long, elastic cables that can be pulled from the PCM. These results are compared with an externally reconstituted model PCM on the cell surface.

  11. 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.

  12. External threats: the dilemma of resource management on the Colorado River in Grand Canyon National park, USA

    NASA Astrophysics Data System (ADS)

    Johnson, R. Roy; Carothers, Steven W.

    1987-01-01

    The United States Congress established Grand Canyon National Park in 1919 to preserve for posterity the outstanding natural attributes of the canyon cut by the Colorado River. In some cases National Park Service attempts to maintain Grand Canyon's natural environment have been thwarted by activities outside the park. One of the most obvious external threats is Glen Canyon Dam, only 26 km upstream from the park boundary. Constructed in 1963, this gigantic dam has greatly altered the physicochemical and biological characteristics of 446 km of the Colorado River in Grand Canyon National Park. The river's aquatic ecosystem has been greatly modified through the loss of indigenous species and the addition of numerous exotics. We consider this an exotic ecosystem. The riparian ecosystem has been less modified, with addition of a few exotics and no loss of natives—this we consider a naturalized ecosystem. The great dilemma now faced by park managers is that, after 20 years of managing resources along a river controlled by Glen Canyon Dam, the Bureau of Reclamation has proposed major changes in operational procedures for the dam. Scientists and managers from the National Park Service, Bureau of Reclamation, and cooperating federal and state resource management agencies are using a systems analysis approach to examine the impacts of various Colorado River flow regimes on aquatic, riparian, and recreational parameters in the park. This approach will help in the development of management alternatives designed to permit the most efficient use of that river's natural resources without their destruction.

  13. Bone histology of the titanosaur Lirainosaurus astibiae (Dinosauria: Sauropoda) from the Latest Cretaceous of Spain

    NASA Astrophysics Data System (ADS)

    Company, Julio

    2011-01-01

    The titanosaur Lirainosaurus astibiae is the only sauropod species known from the Late Cretaceous of the Iberian Peninsula. Lirainosaurus did not reach a gigantic body size and is one of the smallest sauropods discovered to date. Histological analysis of Lirainosaurus bones, focused on diaphyseal transverse sections of appendicular elements, reveals that Lirainosaurus did not exhibit the osseous microstructure typical for large sauropods, but is comparable with that of the coeval titanosaurs Alamosaurus sanjuanensis, Ampelosaurus atacis, and Magyarosaurus dacus, and also shares histological traits with other small to medium-sized sauropodomorph dinosaurs. Lirainosaurus limb bones exhibit a laminar fibrolamellar bone microstructure interrupted by growth marks, fully obliterated in adulthood by intense secondary remodeling processes which tend to replace completely the primary cortex. Lirainosaurus attained smaller sizes than typical sauropods reducing the rate of primary periosteal osteogenesis and developing an extensive secondary remodeling well before the adult size was reached. Histological organization of Lirainosaurus long bones is more mature than observed in basal neosauropods at similar ontogenetic stage, documenting a case of peramorphosis by pre-displacement. This heterochronic growth would be a reversal of the accelerated pattern of bone deposition typical for the sauropod lineage.

  14. 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.

  15. 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

  16. 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.

  17. Mechanical implications of pneumatic neck vertebrae in sauropod dinosaurs

    PubMed Central

    Schwarz-Wings, Daniela; Meyer, Christian A.; Frey, Eberhard; Manz-Steiner, Hans-Rudolf; Schumacher, Ralf

    2010-01-01

    The pre-sacral vertebrae of most sauropod dinosaurs were surrounded by interconnected, air-filled diverticula, penetrating into the bones and creating an intricate internal cavity system within the vertebrae. Computational finite-element models of two sauropod cervical vertebrae now demonstrate the mechanical reason for vertebral pneumaticity. The analyses show that the structure of the cervical vertebrae leads to an even distribution of all occurring stress fields along the vertebrae, concentrated mainly on their external surface and the vertebral laminae. The regions between vertebral laminae and the interior part of the vertebral body including thin bony struts and septa are mostly unloaded and pneumatic structures are positioned in these regions of minimal stress. The morphology of sauropod cervical vertebrae was influenced by strongly segmented axial neck muscles, which require only small attachment areas on each vertebra, and pneumatic epithelia that are able to resorb bone that is not mechanically loaded. The interaction of these soft tissues with the bony tissue of the vertebrae produced lightweight, air-filled vertebrae in which most stresses were borne by the external cortical bone. Cervical pneumaticity was therefore an important prerequisite for neck enlargement in sauropods. Thus, we expect that vertebral pneumaticity in other parts of the body to have a similar role in enabling gigantism. PMID:19801376

  18. 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

  19. Interaction of the Ultra Relativistic Pulsar Plasma with the Upper Atmosphere of the Star-Companion

    SciTech Connect

    Ulyanov, Oleg M.

    2010-08-12

    The basic types of losses of the ultra relativistic electron-positron pulsar plasma in the upper atmosphere of a star-companion are considered. These types include: ionization losses of the medium atoms, their excitation losses, the losses connected with the energies transferred to the particles of plasma, the formation losses of the recoil {delta} electrons and Cherenkov radiation losses of moving particles, bremsstrahlung losses, the synchrotron radiation losses and the losses, connected with the inverse Compton emission. It is shown that the most rapid component of pulsar plasma can reach the top of convective zone. The range of kinetic energies of the plasma particles that reach the upper boundary of the convection zone will correspond to the range of the gigantic dipole resonance (GDR). The result of interaction of the pulsar plasma and of the upper atmosphere of examined star-companion will be the non-homogeneous heating of the local zones of photosphere and boundary between the photosphere and zone of convection on the different depths.

  20. Deficiency of the cyclin-dependent kinase inhibitor, CDKN1B, results in overgrowth and neurodevelopmental delay.

    PubMed

    Grey, William; Izatt, Louise; Sahraoui, Wafa; Ng, Yiu-Ming; Ogilvie, Caroline; Hulse, Anthony; Tse, Eric; Holic, Roman; Yu, Veronica

    2013-06-01

    Germline mutations in the cyclin-dependent kinase inhibitor, CDKN1B, have been described in patients with multiple endocrine neoplasia (MEN), a cancer predisposition syndrome with adult onset neoplasia and no additional phenotypes. Here, we describe the first human case of CDKN1B deficiency, which recapitulates features of the murine CDKN1B knockout mouse model, including gigantism and neurodevelopmental defects. Decreased mRNA and protein expression of CDKN1B were confirmed in the proband's peripheral blood, which is not seen in MEN syndrome patients. We ascribed the decreased protein level to a maternally derived deletion on chromosome 12p13 encompassing the CDKN1B locus (which reduced mRNA expression) and a de novo allelic variant (c.-73G>A) in the CDKN1B promoter (which reduced protein translation). We propose a recessive model where decreased dosage of CDKN1B during development in humans results in a neuronal phenotype akin to that described in mice, placing CDKN1B as a candidate gene involved in developmental delay. PMID:23505216

  1. Deficiency of the Cyclin-Dependent Kinase Inhibitor, CDKN1B, Results in Overgrowth and Neurodevelopmental Delay

    PubMed Central

    Grey, William; Izatt, Louise; Sahraoui, Wafa; Ng, Yiu-Ming; Ogilvie, Caroline; Hulse, Anthony; Tse, Eric; Holic, Roman; Yu, Veronica

    2013-01-01

    Germline mutations in the cyclin-dependent kinase inhibitor, CDKN1B, have been described in patients with multiple endocrine neoplasia (MEN), a cancer predisposition syndrome with adult onset neoplasia and no additional phenotypes. Here, we describe the first human case of CDKN1B deficiency, which recapitulates features of the murine CDKN1B knockout mouse model, including gigantism and neurodevelopmental defects. Decreased mRNA and protein expression of CDKN1B were confirmed in the proband's peripheral blood, which is not seen in MEN syndrome patients. We ascribed the decreased protein level to a maternally derived deletion on chromosome 12p13 encompassing the CDKN1B locus (which reduced mRNA expression) and a de novo allelic variant (c.-73G>A) in the CDKN1B promoter (which reduced protein translation). We propose a recessive model where decreased dosage of CDKN1B during development in humans results in a neuronal phenotype akin to that described in mice, placing CDKN1B as a candidate gene involved in developmental delay. PMID:23505216

  2. 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.

  3. 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 includingTyrannosaurusandAlbertosaurus-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 ofTrexand 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

  4. An Improved Distance Matrix Computation Algorithm for Multicore Clusters

    PubMed Central

    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

  5. 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

  6. Simulations of high-Tc superconductors using the DCA+ algorithm

    NASA Astrophysics Data System (ADS)

    Staar, Peter

    2015-03-01

    For over three decades, the high Tc-cuprates have been a gigantic challenge for condensed matter theory. Even the simplest representation of these materials, i.e. the single band Hubbard model, is hard to solve quantitatively and its phase-diagram is therefore elusive. In this talk, we present the recent algorithmic and implementation advances to the Dynamical Cluster Approximation (DCA). The algorithmic advances allow us to determine self-consistently a continuous self-energy in momentum space, which in turn reduces the cluster-shape dependency of the superconducting transition temperature and thus accelerates the convergence of the latter versus cluster-size. Furthermore, the introduction of the smooth self-energy suppresses artificial correlations and thus reduces the fermionic sign-problem, allowing us to simulate larger clusters at much lower temperatures. By combining these algorithmic improvements with a very efficient GPU accelerated QMC-solver, we are now able to determine the superconducting transition temperature accurately and show that the Cooper-pairs have indeed a d-wave structure, as was predicted by Zhang and Rice.

  7. 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

  8. Search for solar neutrons associated with series of X-class flares during the declining period of solar cycle 23

    NASA Astrophysics Data System (ADS)

    Matsubara, Y.; Muraki, Y.; Sako, T.; Watanabe, K.; Sakai, T.; Shibata, S.; Flueckiger, E.; Buetikofer, R.; Chilingarian, A.; Hovsepyan, G.; Tan, Y.H.; Yuda, T.; Ohonishi, M.; Tsuchiya, H.; Katayose, Y.; Ogasawara, R.; Mizumoto, Y.; Kakimoto, F.; Tsunesada, Y.; Velarde, A.; Ticona, R.; Martinic, N.; Miranda, P.; Valdes-Galicia, J.F.; Gonzalez, L.X.; Hurtado, A.; Musale, O.

    It was surprising that Gigantic solar flares exceeding X-class occurred 10 times in September, 2005, because the activity of the Sun had already been in the declining period. More surprisingly, 4 X-class solar flares occurred in December, 2006, when the activity of the Sun was at the minimum. It is expected that some of these flares were accompanied by the acceleration of ions, which would be observed as solar neutrons or GLEs on the ground. Solar neutron telescopes, which are dedicated to observe solar neutrons and to measure their energies, have been operating during solar cycle 23. Distributed in a worldwide network covering all longitudes they watch the Sun 24 hours a day. In this paper, we report on results of the search for solar neutron events associated with these 14 X-class flares, using data obtained by this international network of solar neutron telescopes. There was no clear evidence for detecting solar neutrons within these periods, except for the significant detection of solar neutrons on September 7, 2005. Details of this particular event will be presented by Sako et al. during this Conference.

  9. 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

  10. 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

  11. 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

  12. The mechanisms of planar cell polarity, growth and the Hippo pathway: Some known unknowns

    PubMed Central

    Lawrence, Peter A.; Casal, José

    2013-01-01

    Planar cell polarity (PCP) is a small but important area of research. In this review we discuss a limited number of topics within the PCP field, chosen because they are difficult, unsolved, controversial or just because we find them interesting. Because Drosophila is the best studied and technically most amenable system we have concentrated on it, but also consider some examples from work on vertebrates. Topics discussed include the number of genetic pathways involved in PCP, as well as the causal relationship between embryonic axes, gradients of morphogens and PCP itself. We consider the vexed question of the roles of the Wnt genes in PCP in both vertebrates and Drosophila. We discuss whether the proteins involved in PCP need to be localised asymmetrically in cells in order to function. We criticise the way the Hippo pathway is described in the literature and ask what its wildtype function is. We explore afresh how the Hippo pathway might be linked both to growth and to PCP through the gigantic cadherin molecule Fat. We offer some new ways of making sense of published results, particularly those relating to the Frizzled/Starry night and Dachsous/Fat systems of PCP. PMID:23592229

  13. 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.

  14. 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

  15. 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.

  16. 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

  17. 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

  18. Tongue reduction for macroglossia in Beckwith Wiedemann syndrome: review and application of new technique.

    PubMed

    Heggie, A A C; Vujcich, N J; Portnof, J E; Morgan, A T

    2013-02-01

    Beckwith Wiedemann syndrome (BWS) is a rare, congenital overgrowth disorder that is characterized by macroglossia, anterior abdominal wall defects, visceromegaly, gigantism, and neonatal hypoglycaemia. Macroglossia may contribute to anterior open bite malocclusion with prognathism, speech articulation disturbances, drooling and the perception of intellectual disability. It was the purpose of this study to review a series of BWS patients who underwent surgical reduction of the tongue by a modified technique with respect to aesthetic and functional outcomes. Seven BWS patients, age 6 months to 21 months, had a 'stellate/anterior wedge' reduction with an anterior rotation flap and were followed up from 4 months to 9 years postoperatively. Assessment of aesthetics together with tongue morphology and mobility were recorded and a postoperative speech evaluation was performed. Minor contour deformities were present in two patients during function but all parents were satisfied with the results. The speech pathology assessment results indicated positive outcomes for speech, oral structure and function, and feeding for all children assessed. This modified technique allows for an adequate reduction of tongue volume with conservation of motor and sensory function as well as preservation of anatomical contour. PMID:23041202

  19. 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

  20. Dependence of heat island phenomena on stable stratification and heat quantity in a calm environment

    NASA Astrophysics Data System (ADS)

    Noto, Katsuhisa

    Dependence of heat island atmosphere on stable stratification and the heat quantity is elucidated by (i) visualizing and measuring the thermal flow over a heated source in a calm and stratified conditions in a laboratory experiment, (ii) finding new type of flow patterns, (iii) determining flow states by the PSD gradients, (iv) comparing with the existing results, and (v) discussing physically to extend the laboratory experiment to a real urban atmosphere. The heat quantity transferred from urban areas makes flow patterns tall. The stable stratification suppresses the plume height, increases the swaying amplitude and turbulence, and produces a vortex pair near the plume top. With increasing the heat quantity and/or decreasing the stable stratification, the plume changes from the type of the steady fumigation with local circulations accumulating heat, which agrees well with Oke's model, to the types of fumigation with the swaying motion, the mushroom, the maximum amplitude of the swaying motion, having a glasses-like vortex pair, and shedding vortices upwards, wherein the last two types of plumes the urban heat easily dissipates upwards. The results agree well with heat island phenomena which occur during night in winter and gigantic columns of clouds which occur during daytime in summer.

  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. Two sun-like superflare stars rotating as slow as the Sun*

    NASA Astrophysics Data System (ADS)

    Nogami, Daisaku; Notsu, Yuta; Honda, Satoshi; Maehara, Hiroyuki; Notsu, Shota; Shibayama, Takuya; Shibata, Kazunari

    2014-04-01

    We report on the results of high dispersion spectroscopy of two "superflare stars," KIC 9766237 and KIC 9944137 with Subaru/HDS. Superflare stars are G-type main sequence stars, but show gigantic flares compared to the Sun, which have recently been discovered in the data obtained with the Kepler spacecraft. Though most of these stars are thought to have a rotation period shorter than 10 d on the basis of photometric variabilities, the two targets of the present paper are estimated to have rotation periods of 21.8 d and 25.3 d. Our spectroscopic results clarified that these stars have stellar parameters similar to those of the Sun in terms of the effective temperature, surface gravity, and metallicity. The projected rotational velocities derived by us are consistent with the photometric rotation period, indicating a fairly high inclination angle. The average strength of the magnetic field on the surface of these stars are estimated to be 1-20 G, by using the absorption line of Ca II 8542. We could not detect any hint of binarity in our spectra, although more data are needed to firmly rule out the presence of an unseen low-mass companion. These results claim that the spectroscopic properties of these superflare stars are very close to those of the Sun, and support the hypothesis that the Sun might cause a superflare.

  3. Nanoscale Disorder and Local Electronic Properties of CaCu,Ti,012: An Integrated Study of Electron, Neutron and X-ray Diffraction, X-ray Absorption Fine Structure and First Principles Calculations

    SciTech Connect

    Zheng, J.C.; Wu, L.; Frenkel, A.I.; Wu, L.; Hanson, J.; Ku, W.; Bozin, E.S.; Billinge, S.J.L.; Zhu, Y.

    2010-04-01

    We report a combined experimental and theoretical study of CaCu{sub 3}Ti{sub 4}O{sub 12}. Based on our experimental observations of nanoscale regions of Ca-Cu antisite defects in part of the structure, we carried out density-functional theory (DFT) calculations that suggest a possible electronic mechanism to explain the gigantic dielectric response in this material. The defects are evident in atomically resolved transmission electron microscopy measurements, with supporting evidence from a quantitative analysis of the electron diffraction and DFT which suggests that such defects are reasonable on energetic grounds. To establish the extent of the defects, bulk average measurements of the local structure were carried out: extended x-ray absorption fine structure (EXAFS), atomic pair-distribution function analysis of neutron powder-diffraction data, and single-crystal x-ray crystallography. The EXAFS data are consistent with the presence of the nanoclustered defects with an estimate of less than 10% of the sample being disordered while the neutron powder-diffraction experiments place an upper of -5% on the proportion of the sample in the defective state. Because of the difficulty of quantifying nanoscale defects at such low levels, further work will be required to establish that this mechanism is operative in CaCu{sub 3}Ti{sub 4}O{sub 12} but it presents a nontraditional plausible avenue for understanding colossal dielectric behavior.

  4. Nanoscale Disorder and Local Electronic Properties of CaCu3Ti4O12: An Integrated Study of Electron, Neutron, and X-ray Diffraction, X-ray Absorption Fine Structure, and First-principles Calculations

    SciTech Connect

    Zheng, J.; Frenkel, A; Wu, L; Hanson, J; Ku, W; Bozin, E; Billinge, S; Zhu, Y

    2010-01-01

    We report a combined experimental and theoretical study of CaCu{sub 3}Ti{sub 4}O{sub 12}. Based on our experimental observations of nanoscale regions of Ca-Cu antisite defects in part of the structure, we carried out density-functional theory (DFT) calculations that suggest a possible electronic mechanism to explain the gigantic dielectric response in this material. The defects are evident in atomically resolved transmission electron microscopy measurements, with supporting evidence from a quantitative analysis of the electron diffraction and DFT which suggests that such defects are reasonable on energetic grounds. To establish the extent of the defects, bulk average measurements of the local structure were carried out: extended x-ray absorption fine structure (EXAFS), atomic pair-distribution function analysis of neutron powder-diffraction data, and single-crystal x-ray crystallography. The EXAFS data are consistent with the presence of the nanoclustered defects with an estimate of less than 10% of the sample being disordered while the neutron powder-diffraction experiments place an upper of {approx}5% on the proportion of the sample in the defective state. Because of the difficulty of quantifying nanoscale defects at such low levels, further work will be required to establish that this mechanism is operative in CaCu{sub 3}Ti{sub 4}O{sub 12} but it presents a nontraditional plausible avenue for understanding colossal dielectric behavior.

  5. 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).

  6. Body-size evolution on islands: are adult size variations in tiger snakes a nonadaptive consequence of selection on birth size?

    PubMed

    Aubret, Fabien

    2012-06-01

    Mean adult size has been used as the traditional measure of body size to explain trends of insular gigantism and dwarfism in a wide array of taxa. However, patterns of variation in body size at birth have received surprisingly little attention, leaving open the possibility that adult body-size differences are nonadaptive consequences of selection acting on neonate body size. Here I used an empirical and correlative approach to test this hypothesis in a mosaic of 12 island and mainland snake populations in Australia. Data collected on 597 adult and 1,084 neonate tiger snakes showed that (1) both adult and neonate mean body sizes varied strongly across populations; (2) prey diversity and size convincingly explained birth-size variations: birth size-notably, gape size-correlated with prey size; (3) neonate snout-vent length was significantly correlated with neonate gape size; and (4) neonate snout-vent length was significantly correlated with adult snout-vent length. Postnatal growth rates recorded under common-garden conditions differed across populations and were correlated with mean prey size. These data collectively suggest that (1) prey size is the main driver for the evolution of body size at birth in gape-limited predators, (2) adult size variations may reflect selective forces acting on earlier life stages, and (3) adult size variations may also reflect resource availability during ontogeny (notably, prey diversity). PMID:22617263

  7. 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

  8. 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

  9. Neptune

    SciTech Connect

    Kinoshita, J.

    1989-11-01

    Voyager 2 took 12 years to reach Neptune, the fourth and final destination of a planetary pilgrimage that included Jupiter, Saturn, and Uranus. Voyage 2 revealed Neptune to be a turbulent world, with giant storm systems rivaling those of Jupiter and fleeting clouds unlike any seen before. Neptune's atmosphere bears distinctive striations and gigantic dark storm spots,including one hurricane as wide across as the earth, which scientists quickly christened the Great Dark Spot. Radio signals, which issue from the planet like a beam from a light house, disclosed that Neptune completes one rotation in 16 hours and three minutes, about one hour faster that had been predicted. Neptune's magnetic field held surprises: its dipole axis is tilted some 50 degrees from the rotation axis and is also displaced from the planet's center by 10,000 kilometers. Voyager confirmed the presence of rings and found six new moons. Images sent back of Triton revealed crenulated landscapes, vast canyons, craters, and peaks. Triton proved to be 2,720 kilometers in diameter. Its atmosphere is exceeding thin and consists mainly of nitrogen. Signs of past volcanism are visible, proving Triton was once a hotter place, presumably because it had an unusual origin. 10 figs.

  10. 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.

  11. 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).

  12. Pressure-induced Polarization Reversal in Z-type Hexaferrite Single Crystal

    NASA Astrophysics Data System (ADS)

    Jeon, Byung-Gu; Chun, Sae Hwan; Kim, Kee Hoon

    2012-02-01

    Multiferroic materials with a gigantic magnetoelectric (ME) coupling at room temperature have been searched for applications to novel devices. Recently, large direct and converse ME effects were realized at room temperature in the so-called Z-type hexaferrite (Ba,Sr)3Co2Fe24O41 single crystals [1,2]. To obtain a new control parameter for realizing a sensitive ME tuning, we studied ME properties of the crystals under uniaxial pressure. Upon applying a tiny uniaxial pressure of about 0.6 GPa, magnetic field-driven electric polarization reversal and anomaly in a M-H loop start to appear at 10 K and gradually disappear at higher temperature above 130 K. By comparing those results with longitudinal magnetostriction at ambient pressure, we propose the pressure-dependent variations of transverse conical spin configuration as well as its domain structure under small magnetic field bias, and point out the possibility of having two different physical origins of the ME coupling in this system. [1] Y. Kitagawa et al., Nat. Mater. 9, 797 (2010) [2] S. H. Chun et al., submitted.

  13. 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.

  14. Revolutionising landscapes: Hydroelectricity and the heavy industrialisation of society and environment in the Comte de Beauharnois, 1927--1948

    NASA Astrophysics Data System (ADS)

    Pelletier, Louis-Raphael

    This dissertation analyses the rapid industrialisation of the rural Comte de Beauharnois and the adjacent stretch of the Fleuve Saint-Laurent owing to the construction, between 1929 and 1948, of a gigantic canal for hydroelectricity production and navigation by an electricity corporation called the Beauharnois Light Heat and Power (BLH&P). Using principally the archives of the BLH&P---especially its complaints files and its rich photographic record---this thesis argues that this process exemplifies the finance capitalist reorganisation of the society and ecosystems of the Canadian province of Quebec from the 19th century to the Great Depression. In keeping with recent work in environmental history, the transformation of rural landscapes and a river for heavy industry is described as an important dimension of a revolution in modes of production. More specifically, I argue that, in the case under study, the finance-capitalist reorganisation of Quebec revolved around two central and explicit projects, one social and the other environmental: the grouping of most individuals in an industrial working class without control over the means of production and the reorganisation of rural landscapes into reservoirs of modern energy and industrial natural resources.

  15. 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".

  16. The evolution of angiosperm lianescence without vessels--climbing mode and wood structure-function in Tasmannia cordata (Winteraceae).

    PubMed

    Feild, Taylor S; Chatelet, David S; Balun, Lawong; Schilling, Edward E; Evans, Robert

    2012-01-01

    • The lack of extant lianescent vessel-less seed plants supports a hypothesis that liana evolution requires large-diameter xylem conduits. Here, we demonstrate an unusual example of a lianoid vessel-less angiosperm, Tasmannia cordata (Winteraceae), from New Guinea. • Wood mechanical, hydraulic and structural measurements were used to determine how T. cordata climbs and to test for ecophysiological shifts related to liana evolution vs 13 free-standing congeners. • The tracheid-based wood of T. cordata furnished low hydraulic capacity compared with that of vessel-bearing lianas. In comparison with most nonclimbing relatives, T. cordata possessed lower photosynthetic rates and leaf and stem hydraulic capacities. However, T. cordata exhibited a two- to five-fold greater wood elastic modulus than its relatives. • Tasmannia cordata provides an unusual example of angiosperm liana evolution uncoupled from xylem conduit gigantism, as well as high plasticity and cell type diversity in vascular development. Because T. cordata lacks vessels, our results suggest that a key limitation for a vessel-less liana is that strong and low hydraulically conductive wood is required to meet the mechanical demands of lianescence. PMID:21995496

  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. Inhomogeneous and nonstationary Hall states of the CDW with quantized normal carriers

    NASA Astrophysics Data System (ADS)

    Brazovskii, S.

    2015-03-01

    We suggest a theory for a deformable and sliding charge density wave (CDW) in the Hall bar geometry for the quantum limit when the carriers in remnant small pockets are concentrated at lowest Landau levels (LL) forming a fractionally (ν < 1) filled quantum Hall state. The gigantic polarizability of the CDW allows for a strong redistribution of electronic densities up to a complete charge segregation when all carriers occupy, with the maximum filling, a fraction ν of the chain length - thus forming the integer quantum Hall state, while leaving the fraction (1 - ν) of the chain length unoccupied. The electric field in charged regions easily exceeds the pinning threshold of the CDW, then the depinning propagates into the nominally pinned central region via sharp domain walls. Resulting picture is that of compensated collective and normal pulsing counter-currents driven by the Hall voltage. This scenario is illustrated by numerical modeling for nonstationary distributions of the current and the electric field. This picture can interpret experiments in mesa-junctions showing depinning by the Hall voltage and the generation of voltage-controlled high frequency oscillations (Yu.I. Latyshev, P. Monceau, A.A. Sinchenko, et al., Presented at ECRYS-2011, unpublished [1]).

  19. 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

  20. 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

  1. 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.

  2. Epstein-Barr virus latent messages with shuffled leader exons: remnants of circumgenomic transcription?

    PubMed Central

    Qu, L; Rowe, D T

    1995-01-01

    The EBNA transcription unit which is active in Epstein-Barr virus-immortalized latently infected B lymphocytes covers approximately 60% of the 172-kb genome. Since the genome exists as a circular double-stranded DNA molecule in latently infected cells, it is conceivable that complete copies are made during transcription. Rather than attempt to detect gigantic RNA molecules directly, we used RNA-PCR to detect incorporation of leader exons into mRNA in a shuffled order. The downstream U leader exon was detected spliced upstream of the internal repeat leader exons W1 and W2 in the polyadenylated RNA fraction of spontaneous lymphoblastoid cell lines, restricted phenotype BL cell lines Wanyanyi and Wewak2, and in B95-8, Raji, and Akata cells. Quantitative competitive RNA-PCR showed that the ratio of U exon-containing EBNA1 messages to U exon-shuffled leader messages was approximately 10:1, with large variation from cell line to cell line, and was not affected by induction of the lytic cycle in B95-8, Raji, or Akata cells. Messages with shuffled exons contained only the C2W1 alternative splice, which does not produce an initiator AUG methionine codon for EBNA4 gene expression. The results provide evidence for long-range exon skipping and imply that genome-length transcripts may occur and participate in viral gene expression in latency. PMID:7815483

  3. 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.

  4. Ionosphere density variations and formation of plasma bubbles caused by thunderstorm currents

    NASA Astrophysics Data System (ADS)

    Kuo, C.; Lee, L. C.; Hsu, R.; Huba, J. D.

    2012-12-01

    The charges and currents associated with a thunderstorm may interact with the middle atmosphere and the ionosphere. Thunderstorm charges may redistribute following the lightning stroke. The transient changes of quasi electric field associated with thunderstorm charge change may cause the transient luminous events, which include elves, halos, sprites, and gigantic jets. In this presentation, we examine the effects of thunderstorm current system on the ionosphere. We use a thunderstorm model to calculate the three-dimensional current flows in the atmosphere and to mimic the upward current above the typical dipolar charge structure inside the thunderstorm. The upward current flows into the ionosphere, while the associated electric field causes the plasma ExB drift motion. The caused plasma motion redistributes the plasma density, leading the variation of TEC. In the nighttime ionosphere, the ExB motion may also cause the formation of the plasma bubbles. We also simulate the effects of thunderstorm charges and flash rates on the ionosphere dynamics, e.g., ionospheric density variations and triggered plasma bubbles.

  5. 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.

  6. Global transients in ultraviolet and red-infrared ranges from data of Universitetsky-Tatiana-2 satellite

    NASA Astrophysics Data System (ADS)

    Garipov, G. K.; Khrenov, B. A.; Klimov, P. A.; Klimenko, V. V.; Mareev, E. A.; Martines, O.; Mendoza, E.; Morozenko, V. S.; Panasyuk, M. I.; Park, I. H.; Ponce, E.; Rivera, L.; Salazar, H.; Tulupov, V. I.; Vedenkin, N. N.; Yashin, I. V.

    2013-01-01

    Light detectors sensitive to wavelength ranges 240-400 nm and beyond 610 nm (which we refer to, for simplicity, as the UV and Red bands) on board Universitetsky-Tatiana-2 satellite have detected transient flashes in the atmosphere of duration 1-128 ms. Measured ratio of the number of Red photons to the number of UV photons indicates that source of transient radiation is at high atmosphere altitude (>50 km). Distribution of events with various photon numbers Qa in the atmosphere found to be different for "luminous" events Qa = 1023 - 1026 (with exponent of differential distribution -2.2) and for "faint" events Qa = 1021 - 1023 (with exponent - 0.97). Luminous event parameters (atmosphere altitude, energy released to radiation, and temporal profiles) are similar to observed elsewhere parameters of transient luminous events (TLE) of elves, sprites, halo, and gigantic blue jets types. Global map of luminous events demonstrates concentration to equatorial zones (latitudes 30°N to 30°S) above continents. Faint events (with number of photons Qa = 1020 - 5ṡ 1021) are distributed more uniformly over latitudes and longitudes. Phenomenon of series of transients registered every minute along satellite orbit (from 3 to 16 transients in one series) was observed. Most TLE-type events belonged to series. Single transients are in average fainter than serial ones. Some transients belonging to series occurs far away of thunderstorm regions. Origin of faint single transients is not clear; several hypothetical models of their production are discussed.

  7. A soft magnetic material for power supply systems of high energy physics experiments

    NASA Astrophysics Data System (ADS)

    Baccaro, S.; Cova, P.; Delmonte, N.; Ghisolfi, E.; Lanza, A.

    2013-01-01

    Most of the high energy physics experiments require their detectors to be embedded in a high intensity magnetic field. In particular the biggest of them, ATLAS, running in the CERN Large Hadron Collider (LHC) particle accelerator, generates a field of 2 T by means of a gigantic toroidal magnet working in open air. Its future phase 2 upgrade plans to move the DC/DC power supplies from the present positions on the external balconies directly on the detectors, where the field is of the order of 1 T. This presentation describes the development of samples made of special magnetic material for inductor cores suitable to work in such an environment. Starting from iron-silicon powders, at FN plant a plastic forming process, based on powder extrusion, injection moulding and sintering, was developed. To get the best compromise between the forming process requirements (good coupling among the metallic powder and the organic components to assure the right mouldability) and the debinding and sintering conditions, several mixtures (with different percentages and kind of organic additives) were experimented. A proper mould was designed and realized to get torous-shaped prototypes. The preliminary results of the physical-microstructural characterization performed on the first prototypes made will be shown.

  8. The Interstellar Medium in the Small Magellanic Cloud: Results from MCELS

    NASA Astrophysics Data System (ADS)

    Winkler, P. F.; Smith, R. C.; Points, S. D.; MCELS Team

    2015-05-01

    The interstellar medium (ISM) provides the playing field where gas and dust are cycled into and out of stars through dynamic and complex interactions, including H II regions, planetary nebulae, supernovae and their remnants, superbubbles, and gigantic supershells. The relative proximity and low extinction make the Large and Small Magellanic Clouds ideal venues for studying the ISM: its constituents, energetics, and interaction with the underlying stellar populations. The Magellanic Cloud Emission Line Survey (MCELS) surveyed both the LMC and SMC over six years using the Curtis Schmidt Telescope at CTIO to produce deep images in H?, [S II] and [O III] lines, plus matched red and green continuum bands for star subtraction. The survey covers the central 88 degrees of the LMC and 4.5 3.5 degrees of the SMCmost of the gaseous extent of both galaxiesat a resolution of 5? or better. This enables us to identify and study structures on scales ranging from 1 pc to global. In this paper we highlight some of the results from MCELS, concentrating on the SMC. These include deep inventories of PNe and SNRs, analysis of H II regions and their optical depth, and extended structures on the scale of the entire galaxy. We also include some brief historical anecdotes.

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. 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 supernovae on the ring structure. One flurry of explosions blew a hole in the ring and formed a giant bubble of hot gas. Secondary star formation on the edge of this bubble appears as an arc extending beyond the ring. [Bottom Left] - Hubble resolves remarkable new detail in the galaxy's core. The reddish color of this region indicates that it contains a tremendous amount of dust and embedded star formation. Bright pinpoints of light are gigantic young star clusters. The picture was taken with the Wide Field Planetary Camera-2 on October 16, 1994. It is a combination of two images, taken in blue and near-infrared light. Credit: Kirk Borne (ST ScI), and NASA

  14. Rare normal faulting earthquake induced by subduction megaquake: example from 2011 Tohoku-oki earthquake

    NASA Astrophysics Data System (ADS)

    Ishiyama, T.; Sugito, N.; Echigo, T.; Sato, H.; Suzuki, T.

    2012-04-01

    A month after March 11 gigantic M9.0 Tohoku-oki earthquake, M7.0 intraplate earthquake occurred at a depth of 5 km on April 11 beneath coastal area of near Iwaki city, Fukushima prefecture. Focal mechanism of the mainshock indicates that this earthquake is a normal faulting event. Based on field reconnaissance and LIDAR mapping by Geospatial Information Authority of Japan, we recognized coseismic surface ruptures, presumably associated with the main shock. Coseismic surface ruptures extend NNW for about 11 km in a right-stepping en echelon manner. Geomorphic expressions of these ruptures commonly include WWS-facing normal fault scarps and/or drape fold scarp with open cracks on their crests, on the hanging wall sides of steeply west-dipping normal fault planes subparallel to Cretaceous metamorphic rocks. Highest topographic scarp height is about 2.3 m. In this study we introduce preliminary results of a trenching survey across the coseismic surface ruptures at Shionohira site, to resolve timing of paleoseismic events along the Shionohira fault. Trench excavations were carried out at two sites (Ichinokura and Shionohira sites) in Iwaki, Fukushima. At Shionohira site a 2-m-deep trench was excavated across the coseismic fault scarp emerged on the alluvial plain on the eastern flank of the Abukuma Mountains. On the trench walls we observed pairs of steeply dipping normal faults that deform Neogene to Paleogene conglomerates and unconformably overlying, late Quaternary to Holocene fluvial units. Sense of fault slip observed on the trench walls (large dip-slip with small sinistral component) is consistent with that estimated from coseismic surface ruptures. Fault throw estimated from separation of piercing points on lower Unit I and vertical structural relief on folded upper Unit I is consistent with topographic height of the coseismic fault scarp at the trench site. In contrast, vertical separation of Unit II, unconformably overlain by Unit I, is measured as about 1.5 m, twice as large as coseismic vertical component of slip, indicative of penultimate seismic event prior to the 2011 earthquake. Abrupt thickening of overlying Unit I may also suggest preexisting topographic relief prior to its deposition. Radiocarbon dating of charred materials included in event horizons and tephrostratigraphy at two sites indicate that penultimate event prior to the 2011 event might occurred at about 40 ka. This normal fault earthquake is in contrast to compressional or neutral stress regimes in Tohoku region before the 2011 megaquake and rarity of the normal faulting earthquake inferred from these paleoseismic studies may reflect its mechanical relation to the gigantic megathrust earthquakes, such as unusual, enhanced extensional stress on the hangingwall block induced by mainshock and/or postseismic creep after the M~9 earthquake.

  15. Unforecasted earthquake and forgotten tsunamis: Lessons from 2011 Tohoku event

    NASA Astrophysics Data System (ADS)

    Satake, K.

    2011-12-01

    The 11 March Tohoku earthquake was the largest (M~9) earthquake in Japan's history. Historical data indicated that large (M<8) earthquakes have repeated in Miyagi-oki since 1793 with an average recurrence interval of 37 years. Because the most recent event occurred in 1978, the probability of an earthquake in the next 30 years was forecasted as 99 %, the highest number of such a long-term forecast around Japan. The March event, however, was not a characteristic type as repeated in the last few centuries, but the size and spatial extent far exceeded the forecast. Very few seismologists anticipated such a gigantic earthquake would occur around Japan. The March earthquake caused about 20,000 fatalities, mostly from its tsunami. Such devastating tsunami was not the first one in Japan. The Sanriku coast, a sawtooth-shaped submerging coast of northern Tohoku, has suffered from damaging tsunamis in the last century. The 1960 Chilean tsunami was about 3 to 5 m high, and caused about 120 fatalities. The 1933 Sanriku tsunami caused up to 20 m tsunami and about 3,000 fatalities. The 1896 Sanriku tsunami caused more than 30 m tsunami with 22,000 fatalities. The 2011 tsunami heights and fatalities were roughly comparable to those from the 1896 tsunami. To the south of Sanriku coast around Sendai, the coastlines are simpler and characterized by flat plains. While the above historic tsunamis were not high on Sendai plain, a historical document and recent geological studies of tsunami deposits have shown that AD 869 Jogan tsunami caused several km of tsunami inundation and a thousand fatalities, very similar to the 2011 tsunami. However, tsunami hazard maps were constructed for the characteristic earthquake with high probability. On March 11, the tsunami warning message was issued by Japan Meteorological Agency (JMA) within 3 minutes of the earthquake. The rupture process of the giant earthquake took a few minutes to complete, hence the estimated earthquake size for the tsunami warning was underestimated. The tsunami arrival time and coastal heights calculated for an earthquake of M 7.9 were announced with tsunami warning message. When a few meters of tsunami was detected on offshore tsunami gauges, JMA upgraded the tsunami warning level, but this information did not reach all the coastal residents particularly at heavily damaged area. The March earthquake and tsunami disaster left many lessons. (1) the long-term forecast should consider prehistoric paleoseismological data, even if historical data for centuries are available, (2) tsunami hazard maps may need to be prepared for infrequent gigantic earthquakes as well as more frequent smaller-sized earthquakes, (3) the past tsunami disaster must be remembered and transmitted to next generation, and (4) upgrading tsunami warning level in emergency situation is rather difficult.

  16. 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 methane hydrates in laboratories because no explosion protection facility is required. In order to prevent rapid gasification, the specimen was prepared without water. Applied total normal stress was 200 kPa and initial normal stress was maintained at about 70 kPa by slightly opening the drainage valve to vent pressured CO2 gas. When the sample was sheared at 30 cm/s, the stress path reached failure line of friction angle of about 37 degrees immediately. However, excess pore air pressure increased soon after and the stress path moved to the origin along the failure line. This means rapid shearing generates frictional heat and it accelerates the gasification of dry ice quickly. On the other hand, crushing of pellets may contribute to increase the total surface area of dry ice and to acceleration of gasification, to some extent. Authors are conducting to examine the velocity weakening characteristics of the samples and upcoming results will give more detail of the mechanism. But this sliding-surface-liquefaction in the mixture supports the possibility of similar accelerating displacement in the sand-MH mixture or boundaries between MH and sand layer induced by certain strong ground motion under sea floor.

  17. The Liang Bua faunal remains: a 95k.yr. sequence from Flores, East Indonesia.

    PubMed

    van den Bergh, G D; Meijer, H J M; Due Awe, Rokhus; Morwood, M J; Szabó, K; van den Hoek Ostende, L W; Sutikna, T; Saptomo, E W; Piper, P J; Dobney, K M

    2009-11-01

    Excavations at Liang Bua, a limestone cave on the island of Flores, East Indonesia, have yielded a well-dated archaeological and faunal sequence spanning the last 95k.yr., major climatic fluctuations, and two human species -H. floresiensis from 95 to 17k.yr.(1), and modern humans from 11k.yr. to the present. The faunal assemblage comprises well-preserved mammal, bird, reptile and mollusc remains, including examples of island gigantism in small mammals and the dwarfing of large taxa. Together with evidence from Early-Middle Pleistocene sites in the Soa Basin, it confirms the long-term isolation, impoverishment, and phylogenetic continuity of the Flores faunal community. The accumulation of Stegodon and Komodo dragon remains at the site in the Pleistocene is attributed to Homo floresiensis, while predatory birds, including an extinct species of owl, were largely responsible for the accumulation of the small vertebrates. The disappearance from the sequence of the two large-bodied, endemic mammals, Stegodon florensis insularis and Homo floresiensis, was associated with a volcanic eruption at 17 ka and precedes the earliest evidence for modern humans, who initiated use of mollusc and shell working, and began to introduce a range of exotic animals to the island. Faunal introductions during the Holocene included the Sulawesi warty pig (Sus celebensis) at about 7ka, followed by the Eurasian pig (Sus scrofa), Long-tailed macaque, Javanese porcupine, and Masked palm civet at about 4ka, and cattle, deer, and horse - possibly by the Portuguese within historic times. The Holocene sequence at the site also documents local faunal extinctions - a result of accelerating human population growth, habitat loss, and over-exploitation. PMID:19058833

  18. Mechanical Analysis of Feeding Behavior in the Extinct “Terror Bird” Andalgalornis steulleti (Gruiformes: Phorusrhacidae)

    PubMed Central

    Degrange, Federico J.; Tambussi, Claudia P.; Moreno, Karen; Witmer, Lawrence M.; Wroe, Stephen

    2010-01-01

    The South American phorusrhacid bird radiation comprised at least 18 species of small to gigantic terrestrial predators for which there are no close modern analogs. Here we perform functional analyses of the skull of the medium-sized (∼40 kg) patagornithine phorusrhacid Andalgalornis steulleti (upper Miocene–lower Pliocene, Andalgalá Formation, Catamarca, Argentina) to assess its mechanical performance in a comparative context. Based on computed tomographic (CT) scanning and morphological analysis, the skull of Andalgalornis steulleti is interpreted as showing features reflecting loss of intracranial immobility. Discrete anatomical attributes permitting such cranial kinesis are widespread phorusrhacids outgroups, but this is the first clear evidence of loss of cranial kinesis in a gruiform bird and may be among the best documented cases among all birds. This apomorphic loss is interpreted as an adaptation for enhanced craniofacial rigidity, particularly with regard to sagittal loading. We apply a Finite Element approach to a three-dimensional (3D) model of the skull. Based on regression analysis we estimate the bite force of Andalgalornis at the bill tip to be 133 N. Relative to results obtained from Finite Element Analysis of one of its closest living relatives (seriema) and a large predatory bird (eagle), the phorusrhacid's skull shows relatively high stress under lateral loadings, but low stress where force is applied dorsoventrally (sagittally) and in “pullback” simulations. Given the relative weakness of the skull mediolaterally, it seems unlikely that Andalgalornis engaged in potentially risky behaviors that involved subduing large, struggling prey with its beak. We suggest that it either consumed smaller prey that could be killed and consumed more safely (e.g., swallowed whole) or that it used multiple well-targeted sagittal strikes with the beak in a repetitive attack-and-retreat strategy. PMID:20805872

  19. Gravity for Detecting Caves: Airborne and Terrestrial Simulations Based on a Comprehensive Karstic Cave Benchmark

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

    Underground caves bear a natural hazard due to their possible evolution into a sink hole. Mapping of all existing caves could be useful for general civil usages as natural deposits or tourism and sports. Natural caves exist globally and are typical in karst areas. We investigate the resolution power of modern gravity campaigns to systematically detect all void caves of a minimum size in a given area. Both aerogravity and terrestrial acquisitions are considered. Positioning of the gravity station is fastest with GNSS methods the performance of which is investigated. The estimates are based on a benchmark cave of which the geometry is known precisely through a laser-scan survey. The cave is the Grotta Gigante cave in NE Italy in the classic karst. The gravity acquisition is discussed, where heights have been acquired with dual-frequency geodetic GNSS receivers and Total Station. Height acquisitions with non-geodetic low-cost receivers are shown to be useful, although the error on the gravity field is larger. The cave produces a signal of -1.5 × 10-5 m/s2, with a clear elliptic geometry. We analyze feasibility of airborne gravity acquisitions for the purpose of systematically mapping void caves. It is found that observations from fixed wing aircraft cannot resolve the caves, but observations from slower and low-flying helicopters or drones do. In order to detect the presence of caves the size of the benchmark cave, systematic terrestrial acquisitions require a density of three stations on square 500 by 500 m2 tiles. The question has a large impact on civil and environmental purposes, since it will allow planning of urban development at a safe distance from subsurface caves. The survey shows that a systematic coverage of the karst would have the benefit to recover the position of all of the greater existing void caves.

  20. The Tornquist Sea and Baltica Avalonia docking

    NASA Astrophysics Data System (ADS)

    Torsvik, Trond H.; Rehnström, Emma F.

    2003-02-01

    Early Ordovician (Late Arenig) limestones from the SW margin of Baltica (Scania-Bornholm) have multicomponent magnetic signatures, but high unblocking components predating folding, and the corresponding palaeomagnetic pole (latitude=19°N, longitude=051°E) compares well with Arenig reference poles from Baltica. Collectively, the Arenig poles demonstrate a midsoutherly latitudinal position for Baltica, then separated from Avalonia by the Tornquist Sea. Tornquist Sea closure and the Baltica-Avalonia convergence history are evidenced from faunal mixing and increased resemblance in palaeomagnetically determined palaeolatitudes for Avalonia and Baltica during the Mid-Late Ordovician. By the Caradoc, Avalonia had drifted to palaeolatitudes compatible with those of SW Baltica, and subduction beneath Eastern Avalonia was taking place. We propose that explosive vents associated with this subduction and related to Andean-type magmatism in Avalonia were the source for the gigantic Mid-Caradoc (c. 455 Ma) ash fall in Baltica (i.e. the Kinnekulle bentonite). Avalonia was located south of the subtropical high during most of the Ordovician, and this would have provided an optimum palaeoposition to supply Baltica with large ash falls governed by westerly winds. In Scania, we observe a persistent palaeomagnetic overprint of Late Ordovician (Ashgill) age (pole: latitude=4°S, longitude=012°E). The remagnetisation was probably spurred by tectonic-derived fluids since burial alone is inadequate to explain this remagnetisation event. This is the first record of a Late Ordovician event in Scania, but it is comparable with the Shelveian event in Avalonia, low-grade metamorphism in the North Sea basement of NE Germany (440-450 Ma), and sheds new light on the Baltica-Avalonia docking.

  1. Earth after the Moon-forming Impact

    NASA Technical Reports Server (NTRS)

    Zahnle, K. J.

    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 approx. 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 fiequently interrupted by volcanic or impact induced thaws. A cartoon history of water, temperature, and carbon dioxide in the aftermath of the moon-formining-impact is shown. How long it stays hot depends on how long it takes to scrub the C02 out of the atmosphere.

  2. Towards to Creation Unit Theory Oil Generation

    NASA Astrophysics Data System (ADS)

    Galant, Yuri

    2014-05-01

    Creating a unified theory of the genesis of oil encompasses all aspects of oil's life beginning from the formation the chemical elements. Globally, in the spatio-temporal aspect oil's life covers a Cosmic (pre geological) stage and geologically stage of formation of the planet Earth. In conces of spatio-temporal aspect unified theory of oil formation is based on the sequence of occurrences of chemical elements from which to create the Planet Earth and its Granite and Basalt Domains. From this standpoint is an independent Oil Domain along with Granite and Basalt. Sequence analysis of the appearance of chemical elements (H, C, N, O, Na, Mg, Al, Si, K, Ca, Ti, Fe, etc.) reveals the genesis of oil at a very early stage of the creation of Earth according appearance first of H and C. Next, according to the sequence of appearance (creation) of the elements are formed of Granite and Basalt Domain. The appearance of: (chemical element - serial number of) H 1, O 8 corresponds to the appearance of the aqueous layer. The appearance of Na 11, Al 13, Si 14 corresponds to the appearance of the Granite layer. The appearance of Ca 20, Fe 26 corresponds to the appearance of the Basalt layer. The process of formation of domains continues to today. Currently, Oil Domain encircles Globe on the south and north and manifests itself from micro quantities to gigantic clusters. In the formation of unit oil involves various methods involving initial elements C and H of various geneses. A unity of theory of oil generation in her polygenic !

  3. Sticky swinging arm dynamics: studies of an acyl carrier protein domain from the mycolactone polyketide synthase.

    PubMed

    Vance, Steven; Tkachenko, Olga; Thomas, Ben; Bassuni, Mona; Hong, Hui; Nietlispach, Daniel; Broadhurst, William

    2016-04-15

    Type I modular polyketide synthases (PKSs) produce polyketide natural products by passing a growing acyl substrate chain between a series of enzyme domains housed within a gigantic multifunctional polypeptide assembly. Throughout each round of chain extension and modification reactions, the substrate stays covalently linked to an acyl carrier protein (ACP) domain. In the present study we report on the solution structure and dynamics of an ACP domain excised from MLSA2, module 9 of the PKS system that constructs the macrolactone ring of the toxin mycolactone, cause of the tropical disease Buruli ulcer. After modification ofapoACP with 4'-phosphopantetheine (Ppant) to create theholoform,(15)N nuclear spin relaxation and paramagnetic relaxation enhancement (PRE) experiments suggest that the prosthetic group swings freely. The minimal chemical shift perturbations displayed by Ppant-attached C3and C4acyl chains imply that these substrate-mimics remain exposed to solvent at the end of a flexible Ppant arm. By contrast, hexanoyl and octanoyl chains yield much larger chemical shift perturbations, indicating that they interact with the surface of the domain. The solution structure of octanoyl-ACP shows the Ppant arm bending to allow the acyl chain to nestle into a nonpolar pocket, whereas the prosthetic group itself remains largely solvent exposed. Although the highly reduced octanoyl group is not a natural substrate for the ACP from MLSA2, similar presentation modes would permit partner enzyme domains to recognize an acyl group while it is bound to the surface of its carrier protein, allowing simultaneous interactions with both the substrate and the ACP. PMID:26920023

  4. 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, "P 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.

  5. Ryanodine receptors/calcium release channels in heart failure and sudden cardiac death.

    PubMed

    Marks, A R

    2001-04-01

    Calcium (Ca2+) ions are second messengers in signaling pathways in all types of cells. They regulate muscle contraction, electrical signals which determine the cardiac rhythm and cell growth pathways in the heart. In the past decade cDNA cloning has provided clues as to the molecular structure of the intracellular Ca2+ release channels (ryanodine receptors, RyR, and inositol 1,4,5-trisphosphate receptors, IP3R) on the sarcoplasmic and endoplasmic reticulum (SR/ER) and an understanding of how these molecules regulate Ca2+ homeostasis in the heart is beginning to emerge. The intracellular Ca2+ release channels form a distinct class of ion channels distinguished by their structure, size, and function. Both RyRs and IP3Rs have gigantic cytoplasmic domains that serve as scaffolds for modulatory proteins that regulate the channel pore located in the carboxy terminal 10% of the channel sequence. The channels are tetramers comprised of four RyR or IP3R subunits. RyR2 is required for excitation-contraction (EC) coupling in the heart. Using co-sedimentation and co-immunoprecipitation we have defined a macromolecular complex comprised of RyR2, FKBP12.6, PKA, the protein phosphatases PP1 and PP2A, and an anchoring protein mAKAP. We have shown that protein kinase A (PKA) phosphorylation of RyR2 dissociates FKBP12.6 and regulates the channel open probability (P(o)). In failing human hearts RyR2 is PKA hyperphosphorylated resulting in defective channel function due to increased sensitivity to Ca2+-induced activation. PMID:11273716

  6. THz Radiation from Mesas of Intrinsic Josephson Junction of Bi2Sr2CaCu2O8+? under Extreme Thermal Inhomogeneity

    NASA Astrophysics Data System (ADS)

    Kadowaki, Kazuo

    2013-03-01

    After the discovery of intense, coherent and continuous electromagnetic waves at terahertz frequencies (THz waves) in 2007,[2] a number of experimental and theoretical works have been carried out to understand the THz radiation phenomena from mesa structure of layered high temperature superconductor Bi2Sr2CaCu2O8+? (hereafter abbreviated as Bi2212). At present after five year intensive studies, the basic mechanism of the THz wave emission can be understood by two principles: one is the ac-Josephson effect working in-between individual intrinsic Josephson junctions in the mesa of Bi2212 and the other is the cavity resonance effect associated with both the geometrical shape and the electromagnetic properties of the mesa structures of Bi2212. However, the precise conditions to obtain strong THz radiation are not yet established well at the stage of mesa fabrication.[3] Moreover, it appears that our recent results of measurement of the inhomogeneous temperature distribution due to the hot-spot formation producing gigantic Joule heat in the mesa may give us much more complicated situations to understand physics of the THz radiation.[4] In this talk based on the experimental results we will provide a unified picture of the THz radiation phenomena in spite of highly nonequilibrium thermal condition, which hopefully will give us a hint to improve the performance and the efficiency of the emission power exceeding 1 mW from a single mesa structure. This will be also useful for various applications. This work was supported in part by CREST project at JST and WPI MANA project at NIMS.

  7. Investigating onychophoran gas exchange and water balance as a means to inform current controversies in arthropod physiology.

    PubMed

    Clusella-Trullas, Susana; Chown, Steven L

    2008-10-01

    Several controversies currently dominate the fields of arthropod metabolic rate, gas exchange and water balance, including the extent to which modulation of gas exchange reduces water loss, the origins of discontinuous gas exchange, the relationship between metabolic rate and life-history strategies, and the causes of Palaeozoic gigantism. In all of these areas, repeated calls have been made for the investigation of groups that might most inform the debates, especially of taxa in key phylogenetic positions. Here we respond to this call by investigating metabolic rate, respiratory water loss and critical oxygen partial pressure (Pc) in the onychophoran Peripatopsis capensis, a member of a group basal to the arthropods, and by synthesizing the available data on the Onychophora. The rate of carbon dioxide release (VCO2) at 20 degrees C in P. capensis is 0.043 ml CO2 h(-1), in keeping with other onychophoran species; suggesting that low metabolic rates in some arthropod groups are derived. Continuous gas exchange suggests that more complex gas exchange patterns are also derived. Total water loss in P. capensis is 57 mg H2O h(-1) at 20 degrees C, similar to modern estimates for another onychophoran species. High relative respiratory water loss rates ( approximately 34%; estimated using a regression technique) suggest that the basal condition in arthropods may be a high respiratory water loss rate. Relatively high Pc values (5-10% O2) suggest that substantial safety margins in insects are also a derived condition. Curling behaviour in P. capensis appears to be a strategy to lower energetic costs when resting, and the concomitant depression of water loss is a proximate consequence of this behaviour. PMID:18805813

  8. 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

  9. Stretchy nerves are an essential component of the extreme feeding mechanism of rorqual whales.

    PubMed

    Vogl, A Wayne; Lillie, Margo A; Piscitelli, Marina A; Goldbogen, Jeremy A; Pyenson, Nicholas D; Shadwick, Robert E

    2015-05-01

    Rorqual whales (Balaenopteridae) are among the largest vertebrates that have ever lived and include blue (Balaenoptera musculus) and fin (Balaenoptera physalus) whales. Rorquals differ from other baleen whales (Mysticeti) in possessing longitudinal furrows or grooves in the ventral skin that extend from the mouth to the umbilicus. This ventral grooved blubber directly relates to their intermittent lunge feeding strategy, which is unique among vertebrates and was potentially an evolutionary innovation that led to gigantism in this lineage [1]. This strategy involves the rorqual whale rapidly engulfing a huge volume of prey-laden water and then concentrating the prey by more slowly expelling the water through baleen plates (Figure 1A). The volume of water engulfed during a lunge can exceed the volume of the whale itself [2]. During engulfment, the whale accelerates, opens its jaw until it is almost perpendicular to the rostrum, and then the highly compliant floor of the oral cavity is inflated by the incoming water [3]. The floor of the oral cavity expands by inversion of the tongue and ballooning of the adjacent floor of the mouth into the cavum ventrale, an immense fascial pocket between the body wall and overlying blubber layer that reaches as far back as the umbilicus. The ventral grooved blubber in fin whales expands by an estimated 162% in the circumferential direction and 38% longitudinally [4]. In fin whales, multiple lunges can occur during a single dive, and the average time between lunges is just over forty seconds [3]. Here, we show that nerves in the floor of the oral cavity of fin whales are highly extensible. PMID:25942546

  10. 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.

  11. 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.

  12. The potential for crustal resources on Mars

    NASA Astrophysics Data System (ADS)

    Cordell, Bruce M.; Gillett, Stephen L.

    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.

  13. The making of an organ

    PubMed Central

    Cuzin, Franis

    2010-01-01

    Based initially on the observation of inheritance patterns at variance with Mendels first law, hereditary epigenetic variations were evidenced in the mouse. Modulating the transcription of a locus, they are induced by RNAs with sequence homology to the transcript. RNAs transferred by the gamete, including sperm, to the fertilized egg appeared to be responsible for transgenerational maintenance of the variant phenotypes. Instances of RNA-dependent variations so far analyzed in the mousea pathological deviation of heart development and a syndrome of gigantism initiated by hyperproliferation of embryonic stem cellssuggest a general dependence of organogenesis on epigenetic controls of gene expression. I conclude it is impossible to say we know the limit of variation.Charles Darwin One of the most fascinating visions offered to the biologist is to watch the fertilized egg ingeniously unfolding a program to create a novel being. Development takes place by activating networks of gene activation that result in the proper adjustment of cell growth and functional differentiation. How is the whole process started? Thoughts are generally centered on the activation of critical genes at the early stages due to a newly acquired organization of their chromatin structures. Is the embryo induced to start a given program by molecules contributed by the maternal and paternal gametes? While genetic determinants are clearly essential, the epigenetic landscape largely dominates our current way of thinking. In this essay, we will focus on the evidence showing that RNA molecules are present in the gametes and that RNA can modulate the robust genetic program of organ formation in the mouse. PMID:20592863

  14. Towards the Understanding of Earthquake Generation in Accreting Subduction Zone: A summary of ODP Leg 196 Activity at the Nankai Subduction Zone.

    NASA Astrophysics Data System (ADS)

    Mikada, H.; Moore, J. C.; Becker, K.; Klaus, A.

    2001-12-01

    Leg 196 was scheduled as a latter half of a two-leg drilling program, ODP legs 190 and 196, at the Nankai Trough where cyclic recurrence of gigantic earthquakes has been conceived in the history. Although it is now well recognized that earthquakes at the Nankai Trough are generated by relative rapid movement of one plate against the other at the plate boundary which can be well described by coseismic tsunami generation mechanisms, observations limited to the Earth_fs surface has constrained us to get more detailed knowledge about real stress accumulation processes, role of fluid, earthquake triggering mechanisms, control on recurrence periodicity, etc., which comes on top of the faulting mechanism due to subduction. A joint effort has begun to understand environmental conditions surrounding the Nankai Trough at the time of ODP leg 131, and a great amount of better knowledge about the accretionary tectonics at Nankai has been stacked in the former legs. Leg 196 was conducted to enhance the results of previous legs using LWD and long term monitoring techniques at two locations, Sites 808 and 1173. During the leg 196, log physical properties, such as porosity, density, etc., around the decollement and the long-term monitoring systems were acquired and will provide data to reveal the role of fluids beneath the seafloor to contribute to further seismogenic studies in terms of geophysical conditions. We think this work is a first step in a long term research process to ultimately drill into the earthquake-producing zone under the Integrated Ocean Drilling Program using the new drillship being constructed in Japan. This future drilling will provide us insights for the seismogenic processes at the Nankai Trough based on the physical evidence on hypotheses brought by the drilling in the legs 131-196.

  15. GHRH excess and blockade in X-LAG syndrome.

    PubMed

    Daly, Adrian F; Lysy, Philippe A; Desfilles, Céline; Rostomyan, Liliya; Mohamed, Amira; Caberg, Jean-Hubert; Raverot, Veronique; Castermans, Emilie; Marbaix, Etienne; Maiter, Dominique; Brunelle, Chloe; Trivellin, Giampaolo; Stratakis, Constantine A; Bours, Vincent; Raftopoulos, Christian; Beauloye, Veronique; Barlier, Anne; Beckers, Albert

    2016-03-01

    X-linked acrogigantism (X-LAG) syndrome is a newly described form of inheritable pituitary gigantism that begins in early childhood and is usually associated with markedly elevated GH and prolactin secretion by mixed pituitary adenomas/hyperplasia. Microduplications on chromosome Xq26.3 including the GPR101 gene cause X-LAG syndrome. In individual cases random GHRH levels have been elevated. We performed a series of hormonal profiles in a young female sporadic X-LAG syndrome patient and subsequently undertook in vitro studies of primary pituitary tumor culture following neurosurgical resection. The patient demonstrated consistently elevated circulating GHRH levels throughout preoperative testing, which was accompanied by marked GH and prolactin hypersecretion; GH demonstrated a paradoxical increase following TRH administration. In vitro, the pituitary cells showed baseline GH and prolactin release that was further stimulated by GHRH administration. Co-incubation with GHRH and the GHRH receptor antagonist, acetyl-(d-Arg(2))-GHRH (1-29) amide, blocked the GHRH-induced GH stimulation; the GHRH receptor antagonist alone significantly reduced GH release. Pasireotide, but not octreotide, inhibited GH secretion. A ghrelin receptor agonist and an inverse agonist led to modest, statistically significant increases and decreases in GH secretion, respectively. GHRH hypersecretion can accompany the pituitary abnormalities seen in X-LAG syndrome. These data suggest that the pathology of X-LAG syndrome may include hypothalamic dysregulation of GHRH secretion, which is in keeping with localization of GPR101 in the hypothalamus. Therapeutic blockade of GHRH secretion could represent a way to target the marked hormonal hypersecretion and overgrowth that characterizes X-LAG syndrome. PMID:26671997

  16. The making of an organ: RNA mediated developmental controls in mice.

    PubMed

    Rassoulzadegan, Minoo; Cuzin, François

    2010-01-01

    Based initially on the observation of inheritance patterns at variance with Mendel's first law, hereditary epigenetic variations were evidenced in the mouse. Modulating the transcription of a locus, they are induced by RNAs with sequence homology to the transcript. RNAs transferred by the gamete, including sperm, to the fertilized egg appeared to be responsible for transgenerational maintenance of the variant phenotypes. Instances of RNA-dependent variations so far analyzed in the mouse-a pathological deviation of heart development and a syndrome of gigantism initiated by hyperproliferation of embryonic stem cells-suggest a general dependence of organogenesis on epigenetic controls of gene expression. "I conclude it is impossible to say we know the limit of variation."-Charles Darwin. One of the most fascinating visions offered to the biologist is to watch the fertilized egg ingeniously unfolding a program to create a novel being. Development takes place by activating networks of gene activation that result in the proper adjustment of cell growth and functional differentiation. How is the whole process started? Thoughts are generally centered on the activation of critical genes at the early stages due to a newly acquired organization of their chromatin structures. Is the embryo induced to start a given program by molecules contributed by the maternal and paternal gametes? While genetic determinants are clearly essential, the epigenetic landscape largely dominates our current way of thinking. In this essay, we will focus on the evidence showing that RNA molecules are present in the gametes and that RNA can modulate the robust genetic program of organ formation in the mouse. PMID:20592863

  17. Twisting Tourniquet(©) Technique: introducing Schnogh, a novel device and its effectiveness in treating primary and secondary lymphedema of extremities.

    PubMed

    Chanwimalueang, Narumon; Ekataksin, Wichai; Piyaman, Parkpoom; Pattanapen, Gedsuda; Hanboon, Borimas K

    2015-10-01

    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

  18. Adaptive semi-supervised recursive tree partitioning: The ART towards large scale patient indexing in personalized healthcare.

    PubMed

    Wang, Fei

    2015-06-01

    With the rapid development of information technologies, tremendous amount of data became readily available in various application domains. This big data era presents challenges to many conventional data analytics research directions including data capture, storage, search, sharing, analysis, and visualization. It is no surprise to see that the success of next-generation healthcare systems heavily relies on the effective utilization of gigantic amounts of medical data. The ability of analyzing big data in modern healthcare systems plays a vital role in the improvement of the quality of care delivery. Specifically, patient similarity evaluation aims at estimating the clinical affinity and diagnostic proximity of patients. As one of the successful data driven techniques adopted in healthcare systems, patient similarity evaluation plays a fundamental role in many healthcare research areas such as prognosis, risk assessment, and comparative effectiveness analysis. However, existing algorithms for patient similarity evaluation are inefficient in handling massive patient data. In this paper, we propose an Adaptive Semi-Supervised Recursive Tree Partitioning (ART) framework for large scale patient indexing such that the patients with similar clinical or diagnostic patterns can be correctly and efficiently retrieved. The framework is designed for semi-supervised settings since it is crucial to leverage experts' supervision knowledge in medical scenario, which are fairly limited compared to the available data. Starting from the proposed ART framework, we will discuss several specific instantiations and validate them on both benchmark and real world healthcare data. Our results show that with the ART framework, the patients can be efficiently and effectively indexed in the sense that (1) similarity patients can be retrieved in a very short time; (2) the retrieval performance can beat the state-of-the art indexing methods. PMID:25656756

  19. 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

  20. Embryology of Early Jurassic dinosaur from China with evidence of preserved organic remains.

    PubMed

    Reisz, Robert R; Huang, Timothy D; Roberts, Eric M; Peng, ShinRung; Sullivan, Corwin; Stein, Koen; LeBlanc, Aaron R H; Shieh, DarBin; Chang, RongSeng; Chiang, ChengCheng; Yang, Chuanwei; Zhong, Shiming

    2013-04-11

    Fossil dinosaur embryos are surprisingly rare, being almost entirely restricted to Upper Cretaceous strata that record the late stages of non-avian dinosaur evolution. Notable exceptions are the oldest known embryos from the Early Jurassic South African sauropodomorph Massospondylus and Late Jurassic embryos of a theropod from Portugal. The fact that dinosaur embryos are rare and typically enclosed in eggshells limits their availability for tissue and cellular level investigations of development. Consequently, little is known about growth patterns in dinosaur embryos, even though post-hatching ontogeny has been studied in several taxa. Here we report the discovery of an embryonic dinosaur bone bed from the Lower Jurassic of China, the oldest such occurrence in the fossil record. The embryos are similar in geological age to those of Massospondylus and are also assignable to a sauropodomorph dinosaur, probably Lufengosaurus. The preservation of numerous disarticulated skeletal elements and eggshells in this monotaxic bone bed, representing different stages of incubation and therefore derived from different nests, provides opportunities for new investigations of dinosaur embryology in a clade noted for gigantism. For example, comparisons among embryonic femora of different sizes and developmental stages reveal a consistently rapid rate of growth throughout development, possibly indicating that short incubation times were characteristic of sauropodomorphs. In addition, asymmetric radial growth of the femoral shaft and rapid expansion of the fourth trochanter suggest that embryonic muscle activation played an important role in the pre-hatching ontogeny of these dinosaurs. This discovery also provides the oldest evidence of in situ preservation of complex organic remains in a terrestrial vertebrate. PMID:23579680