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1

Gigantic thymolipoma.  

PubMed

A 48-year-old woman with an abnormal shadow in chest radiography during an annual physical examination was found by chest computed tomography to have a large fatty mass lesion found to be diagnosed as a gigantic lipoma. Histopathological diagnosis was found to be benign thymolipoma consisting of mature fatty tissue and hyperplastic thymic tissue structures with Hassall,s corpuscles. Although the diagnosis is supported by imaging studies that demonstrate fat and soft tissue within the tumor, variations occur in computed tomography appearance. We suggest that surgical excision be considered when a gigantic intrathoracic lipomatous mass is in scanning as in this case. PMID:11855099

Hirai, Shinji; Hamanaka, Yoshiharu; Mitsui, Norimasa; Kumagai, Hajime; Kobayashi, Taira

2002-01-01

2

A case of severe rhinophyma (gigantic rhinophyma)  

Microsoft Academic Search

Rhinophyma is classically a benign condition whose etiology and pathogenesis are not well understood. A few cases of giant rhinophymas have been reported in the literature. In this article, a case of gigantic, lobulated rhinophyma is presented. The appearance was unusual, and there was cyst formation histologically.

A. Barutcu; A. Atabey; A. H. Gunes

1990-01-01

3

HERNIA DE BOCHDALECK GIGANTE. PRESENTACIÓNDE UN CASO  

Microsoft Academic Search

Se presenta un caso de hernia de Bochdaleck gigante en un varón de 14 años que fue diagnosticado de forma casual. Se revisa la escasa bibliografía sobre la ausencia radiológica de hemidiafragma, comentándose además la aportación del diagnóstico por imagen, fundamentalmente la tomografia axial computarizada (TAC) y la resonancia nuclear magnética (RNM). Finalmente, se revisan las asociaciones más frecuentes de

L. M. Entrenas Costa; T. Domínguez Platas; J. M. Checa Pinilla; J. M. Antona Gómez; F. Fuentes Otero

1992-01-01

4

Formación y evolución de planetas gigantes  

NASA Astrophysics Data System (ADS)

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.

Benvenuto, O. G.; Brunini, A.

5

Blue And Gigantic Jets From Taiwan 2007 TLE Campaign  

Microsoft Academic Search

Blue and gigantic jets are believed to be blue luminous phenomena. In Taiwan 2007 TLE campaign, a multi- wavelength imaging system was deployed with the aim to elucidate the physical and chemical characteristics of TLEs. On 22 July 2007, twenty blue\\/gigantic jets and four sprites were observed to occur over a frontal system in Fujian province of China, about 400km

J. Chou; L. Tsai; C. Kuo; Y. Lee; Y. Chen; C. Hu; A. B. Chen; H. Su; R. Hsu; L. Lee

2007-01-01

6

Analysis of lightning development associated with gigantic jets  

NASA Astrophysics Data System (ADS)

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

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

2011-12-01

7

Radar and lightning analyses of gigantic jet-producing storms Tiffany C. Meyer,1,2  

E-print Network

in the global electric circuit. Gigantic jets (GJs) are part of the TLE family. Like blue jets, they are thought leader-like propagation [Wescott et al., 1998; Wescott et al., 2001]. Gigantic jets have an impulsive re

Cummer, Steven A.

8

A Case of Sotos Syndrome (Cerebral Gigantism) and Psychosis  

Microsoft Academic Search

Sotos syndrome, or cerebral gigantism, is a syndrome of accelerated growth during early childhood, and a number of craniofacial and other physical abnormalities are commonly present. Behavioral and psychiatric manifestations of the disorder include attention deficits, aggressiveness, and social inhibition. The authors describe a case of psychosis that developed in a patient with Sotos syndrome.

Michael T. Compton; Marc Celentana; Brian Price; Andrew C. Furman

2004-01-01

9

On the Vertical Structuring of Gigantic Jets  

NASA Astrophysics Data System (ADS)

Gigantic Jets (GJs) are large-scale electrical discharges between the thundercloud tops and the lower ionosphere. It is estimated that an individual GJ can contribute as much as cloud-to-ground lightning in discharging a thunderstorm system, transferring hundreds of coulombs from thundercloud to the ionosphere [Cummer et al., Nat. Geosci., 2, 617-620, 2009]. GJs are initiated deep inside the thundercloud as intracloud lightning discharges. Owing to a charge imbalance, meaning the upper charge center is depleted with respect to the midlevel charge center, the upward-directed lightning leaders manage to escape through the thundercloud top to form GJs [Krehbiel et al., Nat. Geosci., 1, 233-237, 2008]. As a GJ leader crosses the stratosphere its streamer zone becomes longer and longer, due to the dynamics of streamer growth in a medium with exponentially-decreasing air density, such as in the Earth's atmosphere [Raizer et al., GRL, 33, L23801, 2006]. The speed at which a leader propagates is limited by the air heating of every newly formed leader section, rate of which is slower at upper altitudes in the Earth's atmosphere [da Silva and Pasko, GRL, 39, L13805, 2012]. Despite the expected deceleration of an upward-directed leader, GJs are observed to accelerate as they approach the ionosphere. To address this issue, we propose a simple time-dynamic model for GJ propagation that simulates the upward propagation of a leader discharge accounting for the effects of the expansion of its streamer zone. We propose that the GJ acceleration is a consequence of its vertical structuring and, therefore, can be used to trace the transition altitude between the leader and streamer zone sections of GJs [da Silva and Pasko, GRL, 40, 12, 3315-3319, 2013]. Leaders and streamers are very different electrical discharges in terms of the degree of ionization, temperature, and composition of the plasma inside their channels. A correct description of the vertical structuring of GJs is of fundamental importance for evaluation of their effects in the stratosphere and mesosphere.

Da Silva, C.; Pasko, V. P.

2013-12-01

10

Twin Explosions In Gigantic Dusty Potato Crisp  

NASA Astrophysics Data System (ADS)

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.

2006-05-01

11

Facile Synthesis of Monodisperse Microspheres and Gigantic Hollow Shells of Mesoporous Silica in Mixed Water-Ethanol Solvents  

E-print Network

Facile Synthesis of Monodisperse Microspheres and Gigantic Hollow Shells of Mesoporous Silica of morphologies, such as monodisperse microspheres, gigantic hollow structures comprising a thin shell with a hole, the morphology of mesoporous silica can be regulated from microspheres through gigantic hollow structures

Qi, Limin

12

Occurrence Conditions for Gigantic Jets Connecting the Thundercloud and the Ionosphere  

Microsoft Academic Search

Recently a new type of TLEs called gigantic jets which connect the top of thunderclouds and the lower ionosphere was discovered by ground-based imaging observations. The upper body of gigantic jets is very similar to sprites, while their lower body resembles blue jets. Pasko et al. [2002] reported a video recording of blue jet propagating upward from a thudercloud to

H. Fukunishi; Y. Hiraki; T. Adachi; L. Tong; K. Nanbu

2005-01-01

13

Hereditary Gigantism-the biblical giant Goliath and his brothers  

PubMed Central

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

Donnelly, Deirdre E; Morrison, Patrick J

2014-01-01

14

Gigantic jets between a thundercloud and the ionosphere.  

PubMed

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

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

15

Blue And Gigantic Jets From Taiwan 2007 TLE Campaign  

NASA Astrophysics Data System (ADS)

Blue and gigantic jets are believed to be blue luminous phenomena. In Taiwan 2007 TLE campaign, a multi- wavelength imaging system was deployed with the aim to elucidate the physical and chemical characteristics of TLEs. On 22 July 2007, twenty blue/gigantic jets and four sprites were observed to occur over a frontal system in Fujian province of China, about 400km away from our observation site at Lulin Observatory, Taiwan. All the observed jets showed little blue band (380-510nm) emissions but had easily recognizable signals in red band (570-2700nm). This result indicates that jets observed from ground are reddish and most of the blue emissions are extinct. One of the jets was observed to propagate upward to ~75km elevation, thus it can be identified as a GJ and is similar to the GJ-event observed by Pasko et al (2001). This GJ was launched 200ms after a small jet from the same cloud top. This implies that the smaller jet could be regarded as the leader of this GJ, similar to the stepped/dart leader in a CG flash. Since the blue luminous events in ISUAL data (Su, et. al. 2005 AGU) have similar features as the jets in this ground observation. Thus, we can conclude that the ISUAL blue luminous events also are blue jets or blue starters. Even though blue jets and blue starter have different ISUAL SP2 (N2 2P, 337.0nm), SP3 (N2 1N, 391.4nm) and SP6 (250-390nm) intensities, but the peak ratio between SP2 and SP6 are ~ 0.5 and the peak ratio between SP3 and SP2 are ~ 0.07. This means blue jets and starters possess the same spectral properties and the same degree of ionization. Finally, the relation between jets and the nearby lightning will also be addressed.

Chou, J.; Tsai, L.; Kuo, C.; Lee, Y.; Chen, Y.; Hu, C.; Chen, A. B.; Su, H.; Hsu, R.; Lee, L.

2007-12-01

16

Simulation of leader speeds at gigantic jet altitudes  

NASA Astrophysics Data System (ADS)

Lightning leaders advance in space by creating a heating conversion zone in their tips (i.e., streamer-to-leader transition) in which Joule heating produced by currents of many non-thermal corona streamers transforms into a hot and conducting leader channel. It is believed that the initial stages of transient luminous events termed gigantic jets (GJs) propagating toward the lower ionosphere are directly related to leaders initiated by conventional intra-cloud lightning discharges and escaping upward from thundercloud tops. In the present work we provide quantitative description of speeds of these leaders as a function of leader current and ambient air density (altitude). The direct comparisons with available experimental data indicate that the initial speeds of GJs of ˜50 km/s are consistent with leaders possessing currents 2-8 A. The observed acceleration of GJs can be explained by growth of the leader current, and at high altitudes (low air densities) may be significantly affected by predominance of non-thermal (i.e., streamer) discharge forms.

da Silva, Caitano L.; Pasko, Victor P.

2012-07-01

17

Gigantism and comparative life-history parameters of tyrannosaurid dinosaurs.  

PubMed

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

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

2004-08-12

18

Secondary gigantic jets as possible inducers of sprites  

NASA Astrophysics Data System (ADS)

Three multi-transient luminous events, which were recorded by ISUAL on FORMOSAT-2 and shared a similar generating sequence, are reported. Each event began with a positive cloud-to-ground lightning discharge (CG)-induced sprite, and a secondary gigantic jet (GJ) followed within ~30-50 ms. Then, 1 ms after the GJ, a new sprite occurred near the GJ without associated impulsive lightning signal. The associated electromagnetic signal for one of the events indicates that the GJ is a negative cloud-to-ionosphere discharge carrying a high peak current moment. Cross-analysis of the spectral, image, and electromagnetic data of these three events indicates that the new sprites are likely induced by the secondary GJs, and the high current moment of the secondary GJs appears to be a crucial factor for the induction of the new sprites. Hence, these secondary GJs may have played a role in inducing sprites as much as the negative CGs do for the occurrence of negative sprites.

Lee, Li-Jou; Hsu, Rue-Ron; Su, Han-Tzong; Huang, Sung-Ming; Chou, Jung-Kung; Kuo, Cheng-Ling; Chang, Shu-Chun; Wu, Yen-Jung; Chen, Alfred B.; Frey, Harald U.; Takahashi, Yukihiro; Lee, Lou-Chuang

2013-04-01

19

LTR Retrotransposons Contribute to Genomic Gigantism in Plethodontid Salamanders  

PubMed Central

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

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

20

An evolutionary cascade model for sauropod dinosaur gigantism--overview, update and tests.  

PubMed

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

Sander, P Martin

2013-01-01

21

Lightning development associated with two negative gigantic jets Gaopeng Lu,1  

E-print Network

Lightning development associated with two negative gigantic jets Gaopeng Lu,1 Steven A. Cummer,1 very highfrequency (VHF) lightning mapping networks that the associated lightning character- istics intracloud lightning with upper level channels attempting to exit the cloud, and then produced the upward

Cummer, Steven A.

22

Radar and lightning analyses of gigantic jet-producing storms Tiffany C. Meyer,1,2  

E-print Network

Radar and lightning analyses of gigantic jet-producing storms Tiffany C. Meyer,1,2 Timothy J. Lang range of very high frequency lightning mapping networks. All six were within range of operational radars and two-dimensional lightning network coverage: five within the National Lightning Detection Network

Rutledge, Steven

23

Respiratory Evolution Facilitated the Origin of Pterosaur Flight and Aerial Gigantism  

E-print Network

Respiratory Evolution Facilitated the Origin of Pterosaur Flight and Aerial Gigantism Leon P. A. M of the pterosaurian breathing apparatus through a broad scale comparative study of respiratory structure and function lines of skeletal evidence that indicate that pterosaurs had a highly effective flow-through respiratory

Claessens, Leon

24

Linker Chains of the Gigantic Hemoglobin of the Earthworm Lumbricus terrestris: Primary Structures of  

E-print Network

Linker Chains of the Gigantic Hemoglobin of the Earthworm Lumbricus terrestris: Primary Structures Brian T. Chait,2 and Austen F. Riggs1* 1 Section of Neurobiology, School of Biological Sciences, and Institute of Cellular and Molecular Biology, University of Texas, Austin, Texas 2 Laboratory for Mass

Riggs, Austen

25

Multiinstrumental observations of a positive gigantic jet produced by a winter thunderstorm in Europe  

E-print Network

Multiinstrumental observations of a positive gigantic jet produced by a winter thunderstorm was short at 120­160 ms. This is the first documented GJ which emerged from a maritime winter thunderstorm and winter thunderstorms in the Mediterranean. During the trailing jet phase of the GJ, a sprite with halo

Cummer, Steven A.

26

Parallel gigantism and complex colonization patterns in the Cape Verde scincid lizards Mabuya and  

E-print Network

Parallel gigantism and complex colonization patterns in the Cape Verde scincid lizards MabuyaTa¢ra 35017, Las Palmas de Gran Canaria, Spain The scincid lizards of the Cape Verde islands comprise antaoensis and Mabuya stangeri)))). The Cape Verde archipelago was colonized from West Africa, probably

Carranza, Salvador

27

TRATAMENTO DO GRANULOMA CENTRAL DE CÉLULAS GIGANTES Treatment of Central Giant Cell Granuloma  

Microsoft Academic Search

RESUMO Com o objetivo de discutir as principais formas de tratamento do granuloma central de células gigantes (GCCG), foi realizada uma pesquisa nas bases de dados BBO, LILACS, Scielo (BIREME), Medline e Pubmed à procura de artigos científicos que trouxessem informações a respeito da administração de calcitonina, interferon e corticoesteróides no tratamento do GCCG. O GCCG é uma lesão proliferativa

Ana Cláudia; Amorim Gomes; Érica Cristina Marchiori; Luiz Barbosa de Oliveira Filho; Gabriela Granja Porto

28

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)

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.

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

29

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

PubMed

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

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

30

Gigantic lymphangioma with marked extraluminal progression of the ascending colon: report of a case.  

PubMed

We report a case of gigantic cystic lymphangioma of the ascending colon excised through an open laparotomy. A 34-year-old woman consulted a gynecologist for treatment of infertility. Transvaginal ultrasonography revealed a cystic mass in the pelvis, and she was transferred to our hospital for further investigation. Abdominal enhanced computed tomography (CT) showed a bulky cystic mass, 25 cm or larger, in the abdominal and pelvic cavity. Colonoscopy revealed a cystic submucosal tumor with a cushion sign. Cystic lymphangioma was diagnosed and excised via open surgery as we could not exclude its malignant potential. Pathological examination confirmed lymphangioma. To our knowledge, this is the most gigantic lymphangioma of the colon documented in the literature. About 3 months after surgery, the patient discovered that she was pregnant and her first baby was delivered at term, uneventfully. PMID:25344823

Katsuno, Hidetoshi; Maeda, Koutarou; Hanai, Tsunekazu; Mizuno, Masahiro; Kurashita, Takamitsu; Tsukamoto, Tetsuya

2014-10-26

31

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

PubMed

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

Lamsdell, James C; Braddy, Simon J

2010-04-23

32

Gigantic Cosmic Corkscrew Reveals New Details About Mysterious Microquasar  

NASA Astrophysics Data System (ADS)

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 us

2004-10-01

33

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

PubMed

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

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

2014-10-01

34

The evolution of virulence when parasites cause host castration and gigantism.  

PubMed

It has been suggested that the harm parasites cause to their hosts is an unavoidable consequence of parasite reproduction with costs not only for the host but also for the parasite. Castrating parasites are thought to minimize their costs by reducing host fecundity, which may minimize the chances of killing both host and parasite prematurely. We conducted a series of experiments to understand the evolution of virulence of a castrating bacterium in the planktonic crustacean Daphnia magna. By manipulating food levels during the infection of D. magna with the bacterium Pasteuria ramosa, we showed that both antagonists are resource-limited and that a negative correlation between host and parasite reproduction exists, indicating resource competition among the antagonists. Pasteuria ramosa also induces enhanced growth of its hosts (gigantism), which we found to be negatively correlated with host fecundity but positively correlated with parasite reproduction. Because infected hosts never recovered from infections, we concluded that gigantism is beneficial only for the parasite. Hosts, however, have evolved counteradaptations. We showed that infected hosts have enhanced reproduction before castration. This shift to earlier reproduction increases overall host fecundity and compromises parasite reproduction. Finally, we showed that this resource conflict is subject to genetic variation among host and parasite genotypes within a population and is therefore likely to be an important force in the coevolution of virulence in this system. A verbal model is presented and suggests that the adaptive value of gigantism is to store host resources, which are liberated after parasitic castration for later use by the growing parasite. This hypothesis assumes that infections are long lasting, that is, that they have a high life expectancy. PMID:15540139

Ebert, Dieter; Carius, Hans Joachim; Little, Tom; Decaestecker, Ellen

2004-11-01

35

Are Sick Individuals Weak Competitors? Competitive Ability of Snails Parasitized by a Gigantism-Inducing Trematode  

PubMed Central

Parasitized individuals are often expected to be poor competitors because they are weakened by infections. Many trematode species, however, although extensively exploiting their mollusc hosts, also induce gigantism (increased host size) by diverting host resources towards growth instead of reproduction. In such systems, alternatively to reduced competitive ability due to negative effects of parasitism on host performance, larger size could allow more efficient resource acquisition and thus increase the relative competitive ability of host individuals. We addressed this hypothesis by testing the effect of a trematode parasite Diplostomum pseudospathaceum on the competitive ability of its snail host Lymnaea stagnalis. We experimentally examined the growth of snails kept in pairs in relation to their infection status and intensity of resource competition (i.e. food availability). We found that parasitized snails grew faster and their reproduction was reduced compared to unparasitized individuals indicating parasite-induced gigantism. However, growth of the snails was faster when competing with parasitized individuals compared to unparasitized snails indicating reduced competitive ability due to parasitism. The latter effect, however, was relatively weak suggesting that the effects of the parasite on snail physiology may partly override each other in determining competitive ability. PMID:24205383

Seppälä, Otto; Karvonen, Anssi; Kuosa, Marja; Haataja, Maarit; Jokela, Jukka

2013-01-01

36

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

NASA Astrophysics Data System (ADS)

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.

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

2014-05-01

37

Glassy Protein Dynamics and Gigantic Solvent Reorganization Energy of Plastocyanin David N. LeBard and Dmitry V. Matyushov*  

E-print Network

into the protein reorganization energy prot (see below for a more precise definition). Both v and s are largeGlassy Protein Dynamics and Gigantic Solvent Reorganization Energy of Plastocyanin David N. Le-ergodic conformational fluctuations of the protein, coupled to hydrating water, result in a very broad distribution

Matyushov, Dmitry

38

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

PubMed

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

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

39

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

SciTech Connect

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.

Okuyama, D., E-mail: okuyama@riken.jp, E-mail: nakano@imr.tohoku.ac.jp, E-mail: iwasa@ap.t.u-tokyo.ac.jp; Hatano, T. [RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198 (Japan); Nakano, M., E-mail: okuyama@riken.jp, E-mail: nakano@imr.tohoku.ac.jp, E-mail: iwasa@ap.t.u-tokyo.ac.jp [RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198 (Japan); Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Takeshita, S.; Ohsumi, H.; Tardif, S. [RIKEN SPring-8 Center, Hyogo 679-5148 (Japan); Shibuya, K. [National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8562 (Japan); Yumoto, H.; Koyama, T.; Ohashi, H. [Japan Synchrotron Radiation Research Institute, SPring-8, Hyogo 679-5198 (Japan); Takata, M. [RIKEN SPring-8 Center, Hyogo 679-5148 (Japan); Japan Synchrotron Radiation Research Institute, SPring-8, Hyogo 679-5198 (Japan); Kawasaki, M.; Tokura, Y.; Iwasa, Y., E-mail: okuyama@riken.jp, E-mail: nakano@imr.tohoku.ac.jp, E-mail: iwasa@ap.t.u-tokyo.ac.jp [RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198 (Japan); Quantum-Phase Electronics Center and Department of Applied Physics, University of Tokyo, Tokyo 113-8656 (Japan); Arima, T. [RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198 (Japan); RIKEN SPring-8 Center, Hyogo 679-5148 (Japan); Department of Advanced Materials Science, University of Tokyo, Kashiwa 277-8561 (Japan)

2014-01-13

40

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

NASA Astrophysics Data System (ADS)

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.

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

2009-09-01

41

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

PubMed Central

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

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

2011-01-01

42

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

PubMed Central

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

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

2014-01-01

43

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

SciTech Connect

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.

Belyi, N.

1991-03-01

44

Gigantic jet observation by the ISUAL payload of FORMOSAT-2 satellite  

NASA Astrophysics Data System (ADS)

Gigantic jet is a kind of transient luminous events (TLEs), which was first discovered in 2002 [Su et al]. Based on the 16ms time resolution black/white images, three luminous stages, called leading jet, fully-developed jet, and trailing jet, were identified. At the fully-developed stage, the fully-extended luminous body connected the cloud top at 15km with the E-layer ionosphere at 90km. The leading jet, which can be viewed as the pre-stage of the fully- developed jet, behaved like a stepped leader of cloud-to-ground (CG) lightning. The trailing jets have similar dynamical evolution features as the blue jets, where a funnel-shape jet emerged from the cloud-top and propagating upward. The luminous period of these jets lasted from 300 ms to 500 ms, which is longer than typical sprites but is shorter than that of the large blue jets observed by Pasko et al (2002). From the associated ELF emissions, the charge moment changes of GJs were estimated to be 1000-2000C-km and the polarity was determined to be negative. Both optical and radio signals suggested that GJs were not CG-induced events, and likely are true discharges from thundercloud to the ionosphere. Among the TLE events recorded by the ISUAL payload on the FORMOSAT-2 satellite, a gigantic jet event was identified. The spectrophotometric data recorded by the ISUAL SP reveals that the GJ is more energetic than sprites. The expected spatial-temporal properties of GJ were confirmed by the ISUAL array photometer. The ISUAL AP data indicates that the electric field intensity of GJ is much larger than the sprite QE field intensity above 70 km. Both ISUAL imager and AP data demonstrate that the fully-developed stage in GJ truly is an upward discharge from the cloud-top to ionosphere and plays the similar role as the return stroke in cloud-to-ground lightning. In this paper, the ISUAL data on this fantastic event will be presented, including its spectroscopic data and dynamical properties at 1ms time resolution. The corresponding ELF signals, observed by Onagawa station in Japan and Esrange station in Sweden, will also be shown.

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

2005-12-01

45

Change in the immunophenotype of a somatotroph adenoma resulting in gigantism  

PubMed Central

Background: Examining the pathologic progression of a pituitary adenoma from the point of a prepubescent child to an adult with gigantism affords us an opportunity to consider why patients may develop secretory or functioning tumors and raises questions about whether therapeutic interventions and surveillance strategies could be made to avoid irreversible phenotypic changes. Case Description: A patient underwent a sublabial transsphenoidal resection for a clinically non-functioning macroadenoma in 1999. He underwent radiation treatment and was transiently given growth hormone (GH) supplementation as an adolescent. His growth rapidly traversed several percentiles and he was found to have elevated GH levels. The patient became symptomatic and was taken for a second neurosurgical procedure. Pathology and immunohistochemical staining demonstrated a significantly higher proportion of somatotroph cells and dense granularity; he was diagnosed with a functional somatotroph adenoma. Conclusions: While it is likely that the described observations reflect the manifestations of a functional somatotroph adenoma in development, it is possible that pubertal growth, GH supplementation, its removal, or radiation therapy contributed to the described endocrine and pathologic changes. PMID:25396071

Thawani, Jayesh P.; Bailey, Robert L.; Burns, Carrie M.; Lee, John Y. K.

2014-01-01

46

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

PubMed Central

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

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

2014-01-01

47

Respiratory Evolution Facilitated the Origin of Pterosaur Flight and Aerial Gigantism  

PubMed Central

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

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

2009-01-01

48

A new technique for reconstruction of the current moment waveform related to a gigantic jet from the magnetic field component recorded by an ELF station  

NASA Astrophysics Data System (ADS)

The paper presents a reconstruction of the current moment waveform of the gigantic jet observed optically last winter in Europe, based on the magnetic field component of the ELF electromagnetic field, recorded by the Hylaty station in Poland. Gigantic jets have only been observed so far on a few occasions, and there is still relatively little known about them. In order to analyze the recorded signal we have developed a new technique, which makes it possible to obtain the actual current moment waveform of the lightning discharges associated with the gigantic jet by eliminating from the waveform the effects of both the impulse response of the receiver and the Earth-ionosphere propagation channel. The proposed method can be also used to analyze other waveform observations, especially in the ELF and VLF frequency bands.

Ku?Ak, Andrzej; M?Ynarczyk, Janusz

2011-04-01

49

Gigantic solitary fibrous tumour of extra-peritoneal space. A case report and review of the literature.  

PubMed

Solitary fibrous tumour (SFT) is a rare soft tissue tumour which belongs to fibroblastic/myofibroblastic group of tumours. The most often it appears in pleura, also in pericardium, internal organs, peritoneum and extraperitoenal space. SFT was first described as a new type of pleura's tumour by Klemperer and Rabin in 1931. The histogenesis of SFT's has been discussed for years suggesting its mesothelial origin. Recently, SFT has been classified as a mesenchymal fibroblastic tumour. We report a very rare case of 71-year old man suffering from gigantic solitary fibrous tumour of extraperitoneal space who underwent curative surgery in the Department of General, Gastroenterological and Oncologic Surgery in 2011. PMID:25222582

Guzel, Tomasz; D?browski, Bohdan; Mazurkiewicz, Micha?; Makiewicz, Marcin; Krasno?bski, Ireneusz W

2014-07-01

50

Electromagnetical, Visual and Meteorological Analyses of two Gigantic Jets Observed Over Missouri, USA  

NASA Astrophysics Data System (ADS)

An amateur astronomer operating a Watec 100N camera in Broken Arrow, Oklahoma discovered 2 gigantic jets (GJ) rising out of a thunderstorm over SW Missouri on 20 August 2007, at 9:24:04 and 9:25:48 UTC. They are the first observed to occur over the continental United States and this far poleward (37.2°N). The azimuths of the GJs corresponded with two different cores of a slow-moving multicell storm, spaced apart by 50 km. At distances of 239 and 204 km from the camera, the GJs reached heights of 94 and 83 km, with bright transition zones between 45-61 and 50-64 km. The jets only became visible to the camera at/near completion of the pathway to the ionosphere, followed by a glow moving upward through the transition zone over 250-300 ms (at 1.6-5 104 m/s). The storm cluster was aged 4 hours by the time of the GJs. The events occurred over separate NEXRAD radar echo tops reaching 15 km, with evidence of new strong updrafts from GOES IR imagery and radar hail signatures. Within 5 minutes before each event, flash rates of positive cloud-to-ground flashes increased and dominated over negative by a factor of 3-4 for a few minutes (but low rates), but without quick rises or lulls. Weak NLDN- detected flashes (intracloud) correlated to both events in time and space. One sprite was observed 50 minutes after the events. Initial inspection of ELF-VLF transients recorded by receivers operated by Duke and Stanford universities indicated signals close to the approximate event times, but multi-site analysis has yet to confirm the geographical origin and the likelihood of any possible association.

van der Velde, O. A.; Lyons, W. A.; Cummer, S. A.; Cohen, M. B.; Sentman, D. D.; Jaugey, N.; Nelson, T. E.; Smedley, R.

2007-12-01

51

Sex Determination and Polyploid Gigantism in the Dwarf Surfclam (Mulinia Lateralis Say)  

PubMed Central

Mulinia lateralis, the dwarf surfclam, is a suitable model for bivalve genetics because it is hardy and has a short generation time. In this study, gynogenetic and triploid. M. lateralis were successfully induced. For gynogenesis, eggs were fertilized with sperm irradiated with ultraviolet light and subsequently treated with cytochalasin B to block the release of the second polar body (PB2). Triploidy was induced by blocking PB2 in normally fertilized eggs. The survival of gynogenetic diploids was very low, only 0.7% to 8 days post-fertilization (PF), compared with 15.2% in the triploid groups and 27.5% in the normal diploid control. Larvae in all groups metamorphosed at 8-10 days PF, and there was no significant post-larval mortality. At sexual maturation (2-3 months PF), all gynogenetic diploids were female, and there was no significant difference (P > 0.05) in sex ratio between diploids and triploids. These results suggested that the dwarf surfclam may have an XX-female, XY-male sex determination with Y-domination. Compared with diploids, triploids had a relative fecundity of 59% for females and 80% for males. Eggs produced by triploid females were 53% larger (P < 0.001) in volume than those from diploid females. In both length and weight measurements at three months PF, the gynogenetic diploids were not significantly (P > 0.33) different from normal diploid females, suggesting that inbreeding depression was minimal in meiosis II gynogens. Triploid clams were significantly larger (P < 0.001) than normal diploids. We hypothesize that the increased body-size in triploids was caused by a polyploid gigantism due to the increased cell volume and a lack of cell-number compensation. PMID:7896101

Guo, X.; Allen-Jr., S. K.

1994-01-01

52

Gigantic jets produced by an isolated tropical thunderstorm near Réunion Island  

NASA Astrophysics Data System (ADS)

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

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

2011-10-01

53

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

NASA Astrophysics Data System (ADS)

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

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

2012-08-01

54

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

NASA Astrophysics Data System (ADS)

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.;

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

2012-12-01

55

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

NASA Astrophysics Data System (ADS)

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.

Baro?, I.; Kernstocková, M.; Faridi, M.; Bubík, M.; Milovský, R.; Melichar, R.; Sabouri, J.; Bab?rek, J.

2013-10-01

56

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

PubMed

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

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

2014-09-15

57

Galls and gall makers in plants from the Pé-de-Gigante Cerrado Reserve, Santa Rita do Passa Quatro, SP, Brazil.  

PubMed

Thirty-six morphologically different types of galls were obtained in leaves, leaflets, veins, petioles, stems, tendrils and flower buds from twenty-five species of plants in the Pé-de-Gigante Reserve, municipality of Santa Rita do Passa Quatro, state of São Paulo, Brazil. The host plant species belong to the closely related families Anacardiaceae, Annonaceae, Asteraceae, Bignoniaceae, Caryocaraceae, Erythroxylaceae, Fabaceae, Malpighiaceae, Melastomataceae, Myrtaceae, Ochnaceae, Polygalaceae, Sapindaceae, Sapotaceae, and Smilacaceae. The most common gall makers included Cecidomyiidae (Diptera), Pteromalidae (Hymenoptera) and Diaspididae (Sternorrhyncha-Hemiptera). This is the first report of galls found in the following plant genera: Gochnatia (Asteraceae), Distictela (Bignoniaceae), Banisteriopsis (Malpighiaceae), Ouratea (Ochnaceae), and Bredemeyera (Polygalaceae). The results of this work contribute to the body of knowledge about the relationship among host plants, gall makers, and the gall morphology of Pé-de-Gigante Cerrado Reserve. PMID:16710528

Urso-Guimarães, M V; Scareli-Santos, C

2006-02-01

58

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

SciTech Connect

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.

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

59

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

PubMed Central

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

Olson, Storrs L.; Hearty, Paul J.

2010-01-01

60

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

PubMed Central

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

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

2013-01-01

61

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

PubMed

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

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

2015-02-12

62

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

PubMed Central

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

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

2013-01-01

63

Darwin's "Gigantic Blunder."  

ERIC Educational Resources Information Center

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)

Barrett, Paul H.

1973-01-01

64

No More Gigantism  

ERIC Educational Resources Information Center

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)

Vohra, B. B.

1975-01-01

65

Gigantism treated by pure endoscopic endonasal approach in a case of McCune-Albright syndrome with sphenoid fibrous dysplasia: a case report.  

PubMed

McCune-Albright syndrome (MAS) is an uncommon polyostotic manifestation of fibrous dysplasia in association with at least one endocrinopathy that is mostly associated with precocious puberty and hyperpigmented skin macules named café-au-lait spots. We present an atypical manifestation of McCune-Albright syndrome in a 19-year-old man with the uncommon association of polyostotic fibrous dysplasia and gigantism in the absence of café-au-lait spots and precocious puberty. He presented with a height increase to 202 cm in the previous 3 years, which had become more progressive in the few months prior. Physical examination revealed only a mild facial asymmetry; however, a computed tomography (CT) scan discovered vast areas of voluminous bones with ground-glass density and thickening involving the craniofacial bones and skull base. Magnetic resonance imaging (MRI) found a right stalk shift of the pituitary with a 20 mm pituitary adenoma. We describe the diagnostic and endoscopic endonasal transsphenoidal approach for excision of the tumor. PMID:23307306

Sharifi, Guive; Jalessi, Maryam; Sarvghadi, Farzaneh; Farhadi, Mohammad

2013-12-01

66

Physics of Streamer-to-Leader Transition at Reduced Air Density and Its Implications for the Vertical Structuring of Gigantic Jets  

NASA Astrophysics Data System (ADS)

Gigantic jets (GJs) are observed as filamentary optical flashes leaving thundercloud tops and propagating through the stratosphere and mesosphere at speeds of tens to hundreds of kilometers per second. They culminate connecting to the ionosphere, playing an analogous role to cloud-to-ground lightning in neutralizing thundercloud charge. In the present work, we provide theoretical evidences that GJs and lightning also share common fundamental physics. For this study, we have developed a one-dimensional axisymmetric model to describe the interaction of the electrical current of a streamer corona with air. The model accounts for heating and expansion of air, excitation of vibrational levels of nitrogen molecules, vibrational-translational energy exchange, and 67 chemical reactions involving 10 neutral and 7 charged plasma species. The electron-impact reactions account for: direct, stepwise and associative ionization, two- and three-body attachment, recombination, and detachment. When provided with standard conditions for the leader stem, the model allows one to calculate the streamer-to-leader transition time scale (and leader speed) as a function of the leader current and the ambient air density (or altitude in Earth's atmosphere). Our recent results [da Silva and Pasko, GRL, 39, L13805, 2012] indicate that streamer coronas with currents as low as a few amperes can promote leader formation in the altitude range 20-45 km on the time scales of the GJ phenomenon. We demonstrate that the initial speed of GJs, between ~50-100 km/s, below 30 km altitude, are compatible to speeds of laboratory leaders in the current range of ~2-8 A, evidencing GJs as a manifestation of the leader breakdown mechanism at reduced air density. In the other hand, in observations, GJs are observed to exhibit strong acceleration as they propagate through the middle atmosphere, reaching speeds >1000 km/s, characteristic of streamer discharges. Our analysis of the streamer-to-leader transition process at altitudes >50 km indicates that a leader is unlikely to be formed on the GJ time scales. Thus, the GJ acceleration can be indicative of its vertical structuring: thermalized leader channels at lower altitudes and cold streamer channels in the upper part.

da Silva, C. L.; Pasko, V. P.

2012-12-01

67

Something Old, Something New: El gigante Amapolas  

E-print Network

version of a legend of the Popol Vuh, in which the exalted parrot-king, Gukup-Cakish, is defeated by his subjects, who disguise themselves as muñecos to achieve their victory. Even closer in tone to Amapolas is Matías Montes-Huidobro's Ojos para no ver... shorthand. Alberdi, although not an accomplished dramatist, knew enough to keep his stage population limited for the greatest artistic effect. Some fifty years later, Alfred Jarry was to make the same discovery as he described his ideas for the production...

Labinger, Andrea G.

1982-04-01

68

NIH Researchers Link Chromosome Region to Gigantism  

MedlinePLUS

... Health NIH Research Matters NIH Record Research & Training Medical Research Initiatives Science Highlights Science Education Research in NIH ... National Institutes of Health (NIH): NIH, the nation's medical research agency, includes 27 Institutes and Centers and is ...

69

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

PubMed

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

de Herder, Wouter W

2012-09-01

70

A Gigantic Anogenital Lesion: Buschke-Lowenstein Tumor  

PubMed Central

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

Sandhu, Rikinder; Min, Zaw; Bhanot, Nitin

2014-01-01

71

Manejo anestésico en la exéresis de un tumor intratorácico gigante  

Microsoft Academic Search

Summary We report the case of a young woman with a giant intrathoracic angiomyolipoma accounting for 10% of her weight and occupying 75% of the right hemithorax and 30% of the left. Before anesthetic induction, an arterial line and a central venous catheter were applied for mon- itoring; neck and thoracic punctures were avoided. The trachea was intubated with a

F. Ariz; G. Valderrama; J. Mejía-Mantilla; C. E. Salas; J. Osorio; D. M. Acosta

72

Giant Squid: One Gigantic Mystery (ScienceWorld)  

NSDL National Science Digital Library

This online article is from the Museum's Science Explorations, a collaboration between AMNH and Scholastic designed to promote science literacy. Written for students in grades 6-10, this article from Science World magazine has an interview with AMNH paleontologist Neal Landman, in which he discusses the giant squid and what scientists have been able to learn by studying only dead specimens. There are Web links that offer further opportunities for learning about the giant squid.

73

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

PubMed Central

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 ?-Fe2O3, ?-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, ?-RhxFe2?xO3 shows high frequency millimetre wave absorption up to 209 GHz. ?-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

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

74

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

ERIC Educational Resources Information Center

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)

Sterne, Noelle

1981-01-01

75

Sudden pressure increase in magma reservoir triggered by gigantic lava-dome collapse on Montserrat  

NSDL National Science Digital Library

Dilatometers recorded pressure changes within the Soufrière Hills Volcano's magma chamber during the 13 July 2003 collapse of its� lava dome. Strain data was evaluated to determine the depth of the pressure source. Results suggest an ellipsoidal magma chamber source at a depth of roughly six kilometers and an average radius of about one kilometer. The observed increase in pressure was consistent with the magma containing pressurized bubbles that expanded when the ambient pressure was reduced.

Al., Voight E.; Agu

76

EXPERIMENTAL PRODUCTION OF GIGANTISM BY FEEDING THE ANTERIOR LOBE OF THE HYPOPHYSIS  

PubMed Central

1. Metamorphosed salamanders of the species Ambystoma opacum and Ambystoma tigrinum were fed on a pure diet of the anterior lobe of the hypophysis of cattle; the controls were fed on an abundant diet of earthworms. 2. The rate of growth of the animals fed on the anterior lobe of the hypophysis was greatly increased over the rate of growth of normal animals. 3. Growth of the animals fed on anterior lobe did not cease after they had reached the normal "maximum" size of the species, and experimental giants were produced. 4. The largest animal of the species Ambystoma opacum fed on anterior lobe of the hypophysis was 19 mm. larger than the largest normal animal of this species known to the writer; the largest animal of the species Ambystoma tigrinum fed on anterior lobe is at present about 28 mm. larger than the largest normal animal of the eastern race of this species known to the writer. PMID:19871871

Uhlenhuth, Eduard

1921-01-01

77

Unigas readies for motor fuel surge with supplies from gigantic plant  

SciTech Connect

Nestled away a short distance from the smog and congestion of Mexico City is a sprawling LP-gas plant from which 72 million gallons of propane are shipped annually. Boasting a storage capacity of 865,000 gal. in 19 tanks, this plant is believed to possess the largest total reserve capacity of any such facility south of the border and in all of Latin America. This paper reports on a tour of the Unigas plant in Ixhuatepec, hosted by general director Carlos Venegas Baeza, which provides insight into three major areas: the operations and plans of one of the largest LP-gas companies in Mexico, the booming market in carburetion, and most noteworthy, the technologically advanced safety/security system that has been installed at this point.

Not Available

1992-10-01

78

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

NASA Astrophysics Data System (ADS)

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.

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

2006-07-01

79

Dramatically accelerated growth and extraordinary gigantism of transgenic mud loach Misgurnus mizolepis  

Microsoft Academic Search

Transgenic mud loaches (Misgurnus mizolepis), in which the entire transgene originated from the same species, have been generated by microinjecting the mud loach growth hormone (mlGH) gene fused to the mud loach ß-actin promoter. Out of 4,100 eggs injected, 7.5% fish derived from the injected eggs showed dramatically accelerated growth, with a maximum of 35-fold faster growth than their non-transgenic

Yoon Kwon Nam; Jae Koo Noh; Young Sun Cho; Hyo Jong Cho; Kyu-Nam Cho; Chul Geun Kim; Dong Soo Kim

2001-01-01

80

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

NASA Astrophysics Data System (ADS)

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 ?m long (eight times larger than magnetite produced by magnetotactic bacteria) and elongated hexaoctahedra up to 1.4 ?m 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

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

81

Page 1 of 45 Gigantism among Late Jurassic limulids: new ichnological evidence from  

E-print Network

the Late Devonian to the Oligocene (Table 1). Although Fernández and Pazos (2013) mentioned the relative geological record (Piekowski and Niedwiedzki, 2009; Gaillard, 2011; Diedrich, 2011; Fernández and Pazos, 2013

82

Room-temperature ferroelectricity and gigantic dielectric susceptibility on a supramolecular architecture of phenazine and deuterated chloranilic acid.  

PubMed

Ferroelectricity and large dielectric constant at room temperature have been demonstrated for cocrystals of phenazine and anilic acids constructing supramolecular assemblies. Deuteration of the anilic acids gives rise to an increase by more than 50 K in the transition temperature, which exceeds room temperature for the deuterated chloranilic acid. At room temperature in air, the crystals show a clear polarization hysteresis with a small coercive field. Application of hydrostatic pressure and halogen substitution in the anilic acids bring about the structural effect on the transition temperature in a parallel way, whereas the deuterium substitution does this in a distinct way. The observed large deuteration effect cannot be elucidated by the geometric change of the hydrogen bond, which has been considered as the possible mechanism of ferroelectricity in the conventional hydrogen-bonded with double-well potential. PMID:15810822

Horiuchi, Sachio; Kumai, Reiji; Tokura, Yoshinori

2005-04-13

83

GEOPHYSICAL RESEARCH LETTERS, VOL. 40, 33153319, doi:10.1002/grl.50596, 2013 Vertical structuring of gigantic jets  

E-print Network

GEOPHYSICAL RESEARCH LETTERS, VOL. 40, 3315­3319, doi:10.1002/grl.50596, 2013 Vertical structuring as they approach the ionosphere. In this letter, we discuss the dependence of the leader speed on current density East, University Park, PA 16802-2706, USA. (caitano.dasilva@psu.edu) ©2013. American Geophysical Union

Pasko, Victor

84

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

Microsoft Academic Search

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)

E. Erba

2010-01-01

85

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

PubMed Central

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

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

2013-01-01

86

End-Permian catastrophe by a bolide impact: Evidence of a gigantic release of sulfur from the mantle  

NASA Astrophysics Data System (ADS)

Our studies in southern China have revealed a remarkable sulfur and strontium isotope excursion at the end of the Permian, along with a coincident concentration of impact- metamorphosed grains and kaolinite and a significant decrease in manganese, phosphorous, calcium, and microfossils (foraminifera). These data suggest that an asteroid or a comet hit the ocean at the end of Permian time and caused a rapid and massive release of sulfur from the mantle to the ocean-atmosphere system, leading to significant oxygen consumption, acid rain, and the most severe biotic crisis in the history of life on Earth.

Kaiho, Kunio; Kajiwara, Yoshimichi; Nakano, Takanori; Miura, Yasunori; Kawahata, Hodaka; Tazaki, Kazue; Ueshima, Masato; Chen, Zhongqiang; Shi, Guang R.

2001-09-01

87

Las gigantes HE 0107-5240 i HE 0557-4840, i nuevas busquedas de estralles puebres en metales  

E-print Network

of the iron abundance of HE 0107-5240, based on the detection of two Fe II lines in an UV spectrum of the star with the aforementioned iron abundance, as are the upper limits derived from the non-detection of further Fe II lines have detected the Fe II 3227.74Ã? line in a VLT/UVES spectrum of HE 0107-5240 covering the ultra

Korn, Andreas

88

Aggressive angiomyxoma in pregnancy.  

PubMed

Aggressive angiomyxoma (AA) is a rare, slow-growing mesenchymal neoplasm of vulvo-perineal region. Although AA is common in females of reproductive age, only a few cases during pregnancy have been documented in the English literature. It carries a high risk of local recurrence but rarely metastasizes. The high recurrence rate can partially be due to inadequate excision, which may be due to an incorrect preoperative diagnosis. We present a case of 25-year-old pregnant female presenting with a painless and soft mass attached to left labia majora by a stalk. This mass was clinically thought to be a lipoma. It was completely excised and was diagnosed as AA on histopathology. Gynecologists should consider the diagnosis of AA when a young female especially during her pregnancy presents with a vulvo-perineal mass. Incorrect diagnosis may lead to incomplete excision and recurrence. PMID:25002951

Goyal, Prashant; Agrawal, Dipti; Sehgal, Shelly; Ghosh, Soumyesh; Kumar, Awanindra; Singh, Sompal

2014-05-13

89

Aggressive Angiomyxoma in Pregnancy  

PubMed Central

Aggressive angiomyxoma (AA) is a rare, slow-growing mesenchymal neoplasm of vulvo-perineal region. Although AA is common in females of reproductive age, only a few cases during pregnancy have been documented in the English literature. It carries a high risk of local recurrence but rarely metastasizes. The high recurrence rate can partially be due to inadequate excision, which may be due to an incorrect preoperative diagnosis. We present a case of 25-year-old pregnant female presenting with a painless and soft mass attached to left labia majora by a stalk. This mass was clinically thought to be a lipoma. It was completely excised and was diagnosed as AA on histopathology. Gynecologists should consider the diagnosis of AA when a young female especially during her pregnancy presents with a vulvo-perineal mass. Incorrect diagnosis may lead to incomplete excision and recurrence. PMID:25002951

Goyal, Prashant; Agrawal, Dipti; Sehgal, Shelly; Ghosh, Soumyesh; Kumar, Awanindra; Singh, Sompal

2014-01-01

90

Tunneled modified lotus petal flap for surgical reconstruction of severe introital stenosis after radical vulvectomy  

PubMed Central

INTRODUCTION We presented the anatomical, functional and aesthetic results achieved with lotus petal flap in case of introital stenosis as a results of inadequate primary plastic reconstruction. We discussed the potential advantages of lotus petal flap compared to others vulvar reconstructive techniques. PRESENTATION OF CASE We report a case of a 44-years old woman presenting a severe introital stenosis following radical surgery for vulvar cancer. She could not have a normal sexual activity life because the narrow scarred introitus resulting after primary closure of a large vulvar defect. The patient comes to our attention after three years from primary surgery. Once the scar was removed we performed a vulvoperineal reconstruction with bilateral tunneled lotus petal flaps. DISCUSSION Lotus petal flap is a safe, easy and quick technique, has a good functional and cosmetic results in this young woman, and represents an optimal alternative solution for plastic reconstruction in case of severe introital stenosis after primary closure of large vulvoperineal defect. CONCLUSION Tunneled lotus petal flaps represents a feasible, attractive and versatile surgical reconstructive technique that can be easily performed after surgical treatment of vulvoperineal neoplasms. PMID:22534648

Buda, Alessandro; Confalonieri, Pier Luigi; Rovati, Luca Carlo Vittorio; Signorelli, Mauro; Del Bene, Massimo

2012-01-01

91

Rumors about invasive snakehead fish, dubbed "Frankenfish," have claimed that these toothy beasts breathe air, walk on land, grow to gigantic size, and attack humans. Although many of  

E-print Network

similar to that of bass. However, their diet is more narrow than that of bass. Snakeheads prey very heavily on small fishes and the occasional macroinvertebrate, lizard, or small mam- mal, whereas the diet Science: Best Carp Prevention Plans 3 Science: Invader Dispersal & Success 3 In Focus 4 Resources 4

Jawitz, James W.

92

Parallel gigantism and complex colonization patterns in the Cape Verde scincid lizards Mabuya and Macroscincus (Reptilia: Scincidae) revealed by mitochondrial DNA sequences.  

PubMed Central

The scincid lizards of the Cape Verde islands comprise the extinct endemic giant Macroscincus coctei and at least five species of Mabuya, one of which, Mabuya vaillanti, also had populations with large body size. Phylogenetic analysis based on DNA sequences derived from the mitochondrial cytochrome b, cytochrome oxidase I and 12S rRNA genes (711, 498 and 378 base pairs (bp), respectively) corroborates morphological evidence that these species constitute a clade and that Macroscincus is unrelated to very large skinks in other areas. The relationships are ((M. vaillanti and Mabuya delalandii) (Mabuya spinalis and Macroscincus coctei (Mabuya fogoensis nicolauensis (Mabuya fogoensis antaoensis and Mabuya stangeri)))). The Cape Verde archipelago was colonized from West Africa, probably in the Late Miocene or Early Pliocene period. The north-eastern islands were probably occupied first, after which the ancestor of M. vaillanti and M. delalandii may have originated on Boavista, the ancestor of the latter species arriving on Santiago or Fogo later. The M. fogoensis--M. stangeri clade colonized the islands of Branco, Razo, Santa Luzia and São Vicente from São Nicolau and reached Santo Antão after this. Colonization of these northeastern islands was slow, perhaps because the recipient islands had not developed earlier or because colonization cut across the path of the Canary Current and the Northeast Trade Winds, the main dispersing agents in the region. Rapid extension of range into the southwestern islands occurred later in M. spinalis and then in M. vaillanti and M. delalandii. The long apparent delay between the origin of these species and their southwestern dispersal may have been because there were earlier colonizations of the southern islands which excluded later ones until the earlier inhabitants were exterminated by volcanic or climatic events. The evolution of large size in Macroscincus occurred in the northwestern islands and was paralleled in the eastern and southern islands by populations of M. vaillanti. Both cases of size increase in Cape Verde skinks were accompanied by the development of herbivory. PMID:11487407

Carranza, S.; Arnold, E. N.; Mateo, J. A.; López-Jurado, L. F.

2001-01-01

93

Parallel gigantism and complex colonization patterns in the Cape Verde scincid lizards Mabuya and Macroscincus (Reptilia: Scincidae) revealed by mitochondrial DNA sequences.  

PubMed

The scincid lizards of the Cape Verde islands comprise the extinct endemic giant Macroscincus coctei and at least five species of Mabuya, one of which, Mabuya vaillanti, also had populations with large body size. Phylogenetic analysis based on DNA sequences derived from the mitochondrial cytochrome b, cytochrome oxidase I and 12S rRNA genes (711, 498 and 378 base pairs (bp), respectively) corroborates morphological evidence that these species constitute a clade and that Macroscincus is unrelated to very large skinks in other areas. The relationships are ((M. vaillanti and Mabuya delalandii) (Mabuya spinalis and Macroscincus coctei (Mabuya fogoensis nicolauensis (Mabuya fogoensis antaoensis and Mabuya stangeri)))). The Cape Verde archipelago was colonized from West Africa, probably in the Late Miocene or Early Pliocene period. The north-eastern islands were probably occupied first, after which the ancestor of M. vaillanti and M. delalandii may have originated on Boavista, the ancestor of the latter species arriving on Santiago or Fogo later. The M. fogoensis--M. stangeri clade colonized the islands of Branco, Razo, Santa Luzia and São Vicente from São Nicolau and reached Santo Antão after this. Colonization of these northeastern islands was slow, perhaps because the recipient islands had not developed earlier or because colonization cut across the path of the Canary Current and the Northeast Trade Winds, the main dispersing agents in the region. Rapid extension of range into the southwestern islands occurred later in M. spinalis and then in M. vaillanti and M. delalandii. The long apparent delay between the origin of these species and their southwestern dispersal may have been because there were earlier colonizations of the southern islands which excluded later ones until the earlier inhabitants were exterminated by volcanic or climatic events. The evolution of large size in Macroscincus occurred in the northwestern islands and was paralleled in the eastern and southern islands by populations of M. vaillanti. Both cases of size increase in Cape Verde skinks were accompanied by the development of herbivory. PMID:11487407

Carranza, S; Arnold, E N; Mateo, J A; López-Jurado, L F

2001-08-01

94

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

PubMed

The aim of this study was to evaluate the replacement effect of wheat bran with spineless cactus and urea in heifers. Twenty-four heifers with an average initial weight of 185?±?13 kg were used in this experiment. Four levels of spineless cactus corrected with urea and ammonium sulfate (9:1) were studied: 0, 33, 66, and 100 % replacement with wheat bran. Samples of feed, orts, and feces were analyzed to estimate the intake and digestibility of dry matter (DM) and nutrients. Indigestible neutral detergent fiber was used as an internal marker. The experiment was conducted in a completely randomized design. Dry matter, neutral detergent fiber, and total digestible nutrient intake demonstrated a quadratic effect (P?

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

2014-10-01

95

From Ally McBeal to Sábado GiganteContributions of Television Viewing to the Gender Role Attitudes of Latino Adolescents  

Microsoft Academic Search

Although previous findings indicate that frequent television viewing is associated with holdingmore stereo typical attitudes aboutgender, no studies have examinedthis 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 connections between exposure to this content, viewer involvement, and the gender role beliefs of Latino adolescents.

Rocío Rivadeneyra; L. Monique Ward

2005-01-01

96

Genetics Home Reference: Sotos syndrome  

MedlinePLUS

... deficit hyperactivity disorder ; autosomal ; autosomal dominant ; cancer ; cell ; chromosome ; contiguous ; deletion ; disabilities ; gene ; gigantism ; hyperactivity ; hypotonia ; incidence ; inheritance ; jaundice ; ...

97

Arms races and the evolution of big fierce societies  

Microsoft Academic Search

Abstract The causes of biological gigantism have received much attention, but only for individual organisms. What selection pressures might favour the evolution of gigantic societies? Here we consider the largest single-queen insect societies, those of the Old World army ant, Dorylus; single colonies of which can have 20 million workers. We propose that colony gigantism in Dorylus arises as a

Graeme P. Boswell; Nigel R. Franks; N. F. Britton

2001-01-01

98

Effects of Octreotide Infusion, Surgery and Estrogen on Suppression of Height Increase and 20K Growth Hormone Ratio in a Girl with Gigantism due to a Growth Hormone-Secreting Macroadenoma  

Microsoft Academic Search

We treated an extremely tall 13-year-old girl with a growth hormone (GH)-secreting macroadenoma and GH levels of 120–495 ng\\/ml with a combination of preoperative octreotide infusion, surgery and postoperative octreotide infusion plus estrogen, which resulted in reduced tumor size prior to surgery, reduced GH levels and completely suppressed growth after surgery. 20K GH is produced by alternative splicing of 22K

Masanori Minagawa; Toshiyuki Yasuda; Tomohiro Someya; Yoichi Kohno; Naokatsu Saeki; Yoshihide Hashimoto

2000-01-01

99

The evolution of high energy accelerators  

SciTech Connect

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.

Courant, E.D.

1989-10-01

100

Where the Maths you learn is used  

E-print Network

· Connection speeds and processing power Energy and the Environment (p34-37) · Wind and wave power · Extreme to build gigantic pyramids. At around 140 metres tall, the Great Pyramid of Giza probably took about twenty

Wright, Francis

101

the evolution of one of the most efficient biological sys-tems in the cell. They also have immense potential to be  

E-print Network

, Royer et al. (2006) report the structure of the 3.6 MDa, 180-mer of Lumbricus (earthworm) hemo- globin that the extracellular hemoglobins of the earthworm, Lumbricus terrestris (LtHb), and related annelids are gigantic

Riggs, Austen

102

Mobile continents on Venus.  

NASA Astrophysics Data System (ADS)

The continental matter on Venus moves not only as large blocks (as is the case on Earth). It can also slide downwards as gigantic flows. This form or transportation of matter has been discovered only on Venus so far.

Sukhanov, A. L.

1989-11-01

103

National Institute of Neurological Disorders and Stroke  

MedlinePLUS

... Cerebral Atrophy Cerebral Beriberi Cerebral Gigantism Cerebral Hypoxia Cerebral Palsy Cerebro-Oculo-Facio-Skeletal Syndrome Charcot-Marie-Tooth ... Walker Syndrome Dawson Disease De Morsier's Syndrome Deep Brain ... Palsy Dementia - Multi-Infarct Dementia - Subcortical Dementia With Lewy ...

104

Nuclear Physics with trapped  

E-print Network

Essentially the entire star is consumed in a gigantic explosion Rough analogy: like detonating a hydrogen bomb the size of the Earth that has the mass of the Sun #12;2/2/2013Dan Melconian Nuclear physics

Boas, Harold P.

105

The plating solution and the human body: Complex electrochemical systems  

Microsoft Academic Search

A thesis proposed is that a plating solution is much like the human body. The body is nothing more than a gigantic complex of molecules and chemicals working together in harmony - so is a plating solution.

Dini

1986-01-01

106

Fermi discovers giant bubbles in Milky Way - Duration: 1:33.  

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...

107

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

E-print Network

BiTeI is a polar semiconductor with gigantic Rashba spin-split bands in bulk. We have investigated the effect of pressure on the electronic structure of this material via magnetotransport. Periods of Shubunikov–de Haas ...

Ideue, T.

108

Producción sostenible y conservación de la rana gigante del lago Titikaka (Telmatobius culeus, Anura: Leptodactylidae): un nuevo desafío para La Paz, Bolivia. Conservation and sustainable production of Titikaka's lake giant toad (Telmatobius culeus, Anura: Leptodactylidae): a new challenge to La Paz, Bolivia  

Microsoft Academic Search

Most relevant aspects about sustainable production and industrialization of Telmatobius culeus at Bolivian rural communities were mentioned and analyzed through a biodiversity conservation and industrial quality-controlled processes (more efficient and less contaminating) production proposal. This sustainable production proposal gives a new challenge to region's people, who

Francisco Fontúrbel Rada

109

Pelvic Congestion Syndrome  

PubMed Central

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

Durham, Janette D.; Machan, Lindsay

2013-01-01

110

Efficient Object Identification with Passive RFID Tags  

E-print Network

pastures and soybean fields with bulldozers and chains. He sees fires wiping out such gigantic swaths it's going to get worse fast. "It gives me goose bumps," says Carter, who founded a nonprofit are jacking up world food prices and endangering the hungry. The grain it takes to fill an SUV tank

111

A Science Service FeatureI-By Dr, Charles F. Brooks  

E-print Network

USeS a moist vind to blon into the continent day after day. These summer shoaers are mere individual expressions of a gigantic DlOve- The heating of the continent results in euch an expansion of the air that Thc

112

Vida Nocturna | Vias Chilenas | Hoteles | Rent a Car | Turismo Aventura | A Domicilio | Inmobiliarias | Restaurantes Cosas de la Gentica  

E-print Network

prolongada a las hormonas del sexo opuesto. Para investigar los efectos de la testosterona en la fertilidad que Reconoce su Habla Gusano Se Oculta en Video de YouTube En Cerro Paranal Descubren Estrella Gigante Chile RESERVA TU HOTEL videos de Chile vinos de Chile SERVICIOS a domicilio aerolíneas agencias de

Lummaa, Virpi

113

Riding the Dinosaur Wave.  

ERIC Educational Resources Information Center

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…

Girod, Mark

1998-01-01

114

A New Sauropodomorph Dinosaur from the Early Jurassic of Patagonia and the Origin and Evolution of the Sauropod-type Sacrum  

Microsoft Academic Search

BackgroundThe origin of sauropod dinosaurs is one of the major landmarks of dinosaur evolution but is still poorly understood. This drastic transformation involved major skeletal modifications, including a shift from the small and gracile condition of primitive sauropodomorphs to the gigantic and quadrupedal condition of sauropods. Recent findings in the Late Triassic–Early Jurassic of Gondwana provide critical evidence to understand

Diego Pol; Alberto Garrido; Ignacio A. Cerda; Andrew Allen Farke

2011-01-01

115

Saturn's rings and moons are a model for how planetary systems  

E-print Network

in the night sky. When Galileo became the first person to peer at Saturn through a telescope in 1610, heSaturn's rings and moons are a model for how planetary systems may be forming around nearby stars't know about Saturn's luminous rings, even though the gigantic, gaseous planet is readily visible

116

Electric jets following the occurrence of sprites  

Microsoft Academic Search

Sprites are discharges occurring at the altitudes ~40 to 90 km, which are usually associated with positive cloud-to-ground lightning (+CGs). Electric jets, which include blue jets (BJs) with the terminal altitude of ~40km and gigantic jets (GJs) emanating to the lower ionosphere, are upward discharges from the cloud tops toward the upper atmosphere. From previous ground observations, it has been

L. Lee; J. Chou; S. Huang; S. Chang; Y. Wu; Y. Lee; C. Kuo; A. B. Chen; H. Su; R. Hsu; H. U. Frey; S. B. Mende; Y. Takahashi

2010-01-01

117

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

PubMed

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

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

2014-01-01

118

Gender, Education and Child Labour: A Sociological Perspective  

ERIC Educational Resources Information Center

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,…

Bhat, Bilal Ahmad

2010-01-01

119

IOP PUBLISHING PLASMA PHYSICS AND CONTROLLED FUSION Plasma Phys. Control. Fusion 50 (2008) 124050 (22pp) doi:10.1088/0741-3335/50/12/124050  

E-print Network

. It is argued that the filamentary plasma structures observed in blue jet and gigantic jet discharges in the atmosphere [22, 26, p 74]. Several ground based video recordings of jet-like events, which also electricallyIOP PUBLISHING PLASMA PHYSICS AND CONTROLLED FUSION Plasma Phys. Control. Fusion 50 (2008) 124050

Pasko, Victor

120

HALEY E. BELL ALEXANDER ELECTRICAL ENGINEERING  

E-print Network

plusquam ipsi gigantes vident." - Isaac Newton, 1676 Translation: If I have seen a little further the dynamic behavior of a payload system in orbit. Other factors affecting dynamic behavior may include and synthesize a control law from data collected on orbit. However, for systems of even moderate complexity

121

The Emerging Field of Data Mining  

Microsoft Academic Search

Until recently, data analysts would pour over hundreds, maybe even thousands of bits of data looking for underlying patterns that would reliably predict future outcomes. With the advent of the computer age, people have begun using computers to automate the data gathering process and store the information in databases. Computers are so well suited to this task that gigantic databases

Patrick Whalin

122

The Mystical Effects of Dermatological Vehicles  

Microsoft Academic Search

Topical treatment of the skin is as old as the evolution of man. Instinctively, we try to treat a skin injury or irritation with cooling or soothing substances. Even animals lick their wounds, trusting instinctively in the healing power of saliva. When did this archaic pattern of treatment take the gigantic leap from folk medicine to modern drug therapy? This

Christian Surber; Eric W. Smith

2005-01-01

123

Hypothetical endosymbiontic zooxanthellae in rudists are not needed to explain their ecological niches and thick shells in comparison with hermatypic corals  

Microsoft Academic Search

Fragments of gigantic Durania farafrahensis Douvillé from Maastrichtian pelagic settings (Ghareb chalk) in southern Israel triggered the re-evaluation of the hypothetical symbiosis of rudists with photosynthesizing zooxanthellae. This Durania lived as separate individuals on the muddy bottom of the deep sea and hence was the only rigid substrate to which sponges, octocorals and algae probably attached, attracting other organisms for

Z. Lewy

1995-01-01

124

Channels in the Solar System  

Microsoft Academic Search

Among the major discoveries made by planetary missions, channel structures, formed by a wide range of fluids such as water and lavas, have proven to be surprisingly common. Recent identification of gigantic flood channels in continental regions and submarine channels on the continental shelves provide new channel categories to an already rich inventory of terrestrial channels. Sinuous rilles on the

Goro Komatsu; Victor R. Baker

1996-01-01

125

Y E A R I N R E V I E W JETPROPULSIONLABORATORY  

E-print Network

of the solar system's planets. Today we have more than a dozen missions flying, and many more in various #12 combined for a simulated view of the red planet. The gigantic canyon system is 20 #12;Y E A R I N R E V I E W 1 DIRECTOR'S MESSAGE 4 INTRODUCTION 6 SOLAR.SYSTEM EXPLORATION 12 MARS EXPLORATION 17 EARTH

Waliser, Duane E.

126

Swimming at low Reynolds number: a beginners guide to undulatory locomotion  

Microsoft Academic Search

Undulatory locomotion is a means of self-propulsion that relies on the generation and propagation of waves along a body. As a mode of locomotion it is primitive and relatively simple, yet can be remarkably robust. No wonder then, that it is so prevalent across a range of biological scales from motile bacteria to gigantic prehistoric snakes. Key to understanding undulatory

Netta Cohen; Jordan H. Boyle

2010-01-01

127

UNITED STATES FISH COMMISSION. STOUKINGI T H E STETTINER IiAlTF WIT11 CARP.`  

E-print Network

the Megdeburgische Zeitung, No.501, Magdoburg, Ootobur 27, 1881.1 A truly gigantic enterprise which will greatly of starting the enterprise would be too great, and the par- ties to profit by this arrangment would procure the required 22,000,000 of carp, not by buy- ing them, but in the simplest manner in the world

128

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

ERIC Educational Resources Information Center

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…

Garofalo, Reebee

2011-01-01

129

EDITORIAL COMMENTARY Innovation in optical imaging: Looking inside the heart  

E-print Network

. Electrophysiology usually is studied in one group of hearts, anatomy and contractility in another, and molec- ularEDITORIAL COMMENTARY Innovation in optical imaging: Looking inside the heart Igor R. Efimov, Ph in addressing such gigantic problems as atrial fibril- lation and heart failure. Currently, new synthesis

130

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

ERIC Educational Resources Information Center

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)

Eller, Lennee; Grigsby, Eugene, Jr.

2003-01-01

131

Compact Muon Solenoid: largest physics experiment to be held in 2007  

E-print Network

"over the last fifteen years about 2'300 engineers and scientists from over 150 scientific institutions in 37 countries around the world have worked together to design and build a gigantic general-purpose particle detector, what is called the Compact Muon Solenoid (CMS)." (1 page)

Atkins, William

2007-01-01

132

RECONSTRUCTION AND LANDSCAPE ANALYSIS OF THE JUPITER SANCTUARY AT BAALBEK USING 3D CG  

Microsoft Academic Search

The Jupiter Sanctuary at Baalbek, Jordan, is one of the most grandiose sanctuaries of the Roman antiquity. Its architectural magnificence must have been the last phase of the development which the ancient Mediterranean civilization had sought for. The gigantic building complex of the Propylon, courts, surrounding stoas, and the temple itself were laid around a single axis, forming the symmetrical

J. Ito; S. Sueyasu

133

\\  

Microsoft Academic Search

Amazon Rainforest is endowed with a wide range of natural resources. Ancestral com- munities depended on the forest for their livelihoods and displayed a good repertoire of imaginative forms of resource management, adapted to climate extremes in temperature and rainfall. From the midst of the 1900's, however, the Amazon Rainforest became a labour safety valve, perceived as a gigantic reserve

Isabel Maria Madaleno

2008-01-01

134

Shake It up  

ERIC Educational Resources Information Center

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…

Gilstrap, Tatiana; Sheldon, Peter; Schimmoeller, Peggy

2010-01-01

135

Fossils and Dinosaurs--A Fully Integrated Instructional Unit.  

ERIC Educational Resources Information Center

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…

Kuehl, Matt; And Others

136

The class material is designed to address fundamental yet extremely interesting questions about earthquakes and plate tectonic activity and their cyclicity. For example: Just why and how are earthquakes generated at plate edges and  

E-print Network

earthquakes and plate tectonic activity and their cyclicity. For example: Just why and how are earthquakes? Ideas about interactions of the various components of the plate tectonic model and its attendant of crustal deformation produced during complex plate tectonic interactions. Earth is a gigantic heat engine

137

Introduction The Sun is a mass of incandescent gas  

E-print Network

and isotopic compositions, we can analyze actual pieces of stars in the laboratory, using mass spectrometersChapter 1 Introduction The Sun is a mass of incandescent gas A gigantic nuclear furnace Building hydrogen into helium At a temperature of millions of degrees They Might be Giants We are stardust Joni

Nittler, Larry R.

138

Review of the Solar Array Telescopes David A. Smith  

E-print Network

, solar tower facilities were built in several countries to generate electricity, or as high temperature, high heat research facilities. Their gigantic mirror areas, on hundreds, even thousands, of alt that of the Cherenkov imaging tele- scopes have been the "solar tower" detectors. They use > 2000 m2 mirror areas

Paris-Sud XI, Université de

139

Mining heterogeneous information networks: the next frontier  

Microsoft Academic Search

Real world physical and abstract data objects are interconnected, forming gigantic, interconnected networks. By structuring these data objects into multiple types, such networks become semi-structured heterogeneous information networks. Most real world applications that handle big data, including interconnected social media and social networks, scientific, engineering, or medical information systems, online e-commerce systems, and most database systems, can be structured into

Jaiwei Han

2012-01-01

140

First insights into the biodiversity and biogeography of the Southern Ocean deep sea  

Microsoft Academic Search

Shallow marine benthic communities around Antarctica show high levels of endemism, gigantism, slow growth, longevity and late maturity, as well as adaptive radiations that have generated considerable biodiversity in some taxa. The deeper parts of the Southern Ocean exhibit some unique environmental features, including a very deep continental shelf and a weakly stratified water column, and are the source for

Angelika Brandt; Andrew J. Gooday; Simone N. Brandão; Saskia Brix; Wiebke Brökeland; Tomas Cedhagen; Madhumita Choudhury; Nils Cornelius; Bruno Danis; Ilse de Mesel; Robert J. Diaz; David C. Gillan; Brigitte Ebbe; John A. Howe; Dorte Janussen; Stefanie Kaiser; Katrin Linse; Marina Malyutina; Jan Pawlowski; Michael Raupach; Ann Vanreusel

2007-01-01

141

Tertiary structure of an immunoglobulin-like domain from the giant muscle protein titin: a new member of the I set  

Microsoft Academic Search

Background: Titin is a gigantic protein located in the thick filament of vertebrate muscles. The putative functions of titin range from interactions with myosin and other muscle proteins to a role in muscle recoil. Analysis of its complete sequence has shown that titin is a multi-domain protein containing several copies of modules of 100 amino acids each. These are thought

Mark Pfuhl; Annalisa Pastore

1995-01-01

142

Centroid single force inversion of seismic waves generated by landslides  

Microsoft Academic Search

The centroid moment tensor (CMT) waveform inversion method of Dziewonski et al. (1981) is modified to analyze long period seismic waves generated by ``single force'' events such as the gigantic landslides associated with the 1980 eruption of Mount St. Helens. We refer to the method as centroid single force (CSF) inversion. As the result of the inversion we obtain the

Hitoshi Kawakatsu

1989-01-01

143

Macrodystrophia lipomatosa with associated fibrolipomatous hamartoma of the median nerve.  

PubMed

Macrodystrophia lipomatosa (MDL) is a rare disease typically causing localized gigantism and is often associated with a fibrolipomatous hamartoma (FH) of the median or plantar nerve. A previously unreported case of MDL with associated FH of the median nerve is presented. PMID:10786987

Brodwater, B K; Major, N M; Goldner, R D; Layfield, L J

2000-01-01

144

Macrodystrophia lipomatosa with associated fibrolipomatous hamartoma of the median nerve  

Microsoft Academic Search

Macrodystrophia lipomatosa (MDL) is a rare disease typically causing localized gigantism and is often associated with a fibrolipomatous\\u000a hamartoma (FH) of the median or plantar nerve. A previously unreported case of MDL with associated FH of the median nerve\\u000a is presented.

Brian K. Brodwater; Nancy M. Major; Richard D. Goldner; Lester J. Layfield

2000-01-01

145

Cambodia: Lasting key to Southeast Asia's stability  

Microsoft Academic Search

Despite many positive changes inside Cambodia in recent years, it remains the region's weakest spot: It is caught forever between Vietnam's slow but inexorable expansion southward and westward over the centuries, Thailand's historic instinct to play hostile neighboring elements off against each other as a means of guaranteeing its own survival, and gigantic China to the north. With Russia and

Robert H. Miller

1995-01-01

146

BotEC: The Right Eye of the Man in the Moon  

NSDL National Science Digital Library

Question The "right eye" of the Man in the Moon is really Mare Imbrium, the central portion of a gigantic multi-ring basin formed by a colossal meteorite impact several billion years ago. Which of the following is approximately the same size as Mare Imbrium? Choose from the Pacific Ocean, the North Atlantic Ocean, Australia, Texas, and New York State.

Tewksbury, Barb

147

The Quaternary vegetation and landscape evolution of Novaya Zemlya in the light of palynological records  

Microsoft Academic Search

The paper presents the results of paleoenvironmental (pollen) investigations of Novaya Zemlya throughout all the Quaternary, including Eopleistocene, Pleistocene and Holocene. Clear evidence of continuity between the modern flora and paleofloras confirms the lack of sharp and continuous interruptions in the vegetation development in high latitudes as well as the absence of gigantic ice sheets in the Eastern Arctic. During

Leonid Serebryanny; Eugeniya Malyasova

1998-01-01

148

Programao Cultural da Festa da Famlia 2013 1-Ciclismo  

E-print Network

- Atividades recreativas a. Tenda Quebra Cuca - Jogos de raciocínio; TANGRAN b. Jogos de mesa em madeira c. Jogos Gigantes d. Cama elástica e. Mini Futebol f.Mini Basquete g. Mini Vôlei h. Oficinas de Paraquedas

Floeter, Sergio Ricardo

149

Tese Doutoramento Cotutela Internacional U.Minho: Cincias da Comunicao, Teoria da Cultura  

E-print Network

Gulliver são um salão de jogos gigante, também um livro, por mais científico que seja, contém os brinquedos ilustrado Compreendendo a cultura visual contemporânea como resultante do jogo vivido entre as condições

Boyer, Edmond

150

New pelomedusoid turtles from the late Palaeocene Cerrejón Formation of Colombia and their implications for phylogeny and body size evolution  

Microsoft Academic Search

Pelomedusoides comprises five moderate-sized extant genera with an entirely Southern Hemisphere distribution, but the fossil record of these turtles reveals a great diversity of extinct taxa, documents several instances of gigantism, and indicates a complex palaeobiogeographical history for the clade. Here, we report new pelomedusoid turtle fossils from the late Palaeocene Cerrejón Formation of Colombia. The most complete of these

Edwin A. Cadena; Daniel T. Ksepka; Carlos A. Jaramillo; Jonathan I. Bloch

2012-01-01

151

Composición química de cúmulos globulares galácticos: metalicidades derivadas a partir de fotometría de Washington  

NASA Astrophysics Data System (ADS)

Se presentan temperaturas efectivas y abundancias de 183 gigantes rojas en 7 cúmulos globulares galácticos, derivadas a partir de fotometría de Washington realizada en Cerro Tololo. Las metalicidades provienen de una calibración que tiene en cuenta la disminución de sensibilidad de algunos índices con la temperatura. Los valores medios de [Fe/H] obtenidos oscilan entre -1.2 y -2.15, con errores típicos del orden de 0.2 salvo un par de excepciones. Teniendo en cuenta que el índice (C-T1) es significativamente más sensible a la metalicidad que (V-I), se presenta una calibración de abundancia basada en el color (C-T1)o de la rama gigante roja para una determinada magnitud absoluta M(T1). Las abundancias derivadas confirman en general la escala de Zinn (1985, ApJ, 293, 424).

Torres, M. C.; Clariá, J. J.

152

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

PubMed Central

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

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

2012-01-01

153

Characterization of strong light-matter coupling in semiconductor quantum-dot microcavities via photon-statistics spectroscopy  

E-print Network

It is shown that spectrally resolved photon-statistics measurements of the resonance fluorescence from realistic semiconductor quantum-dot systems allow for high contrast identification of the two-photon strong-coupling states. Using a microscopic theory, the second-rung resonance is analyzed and optimum excitation conditions are determined. The computed photon-statistics spectrum displays gigantic, experimentally robust resonances at the energetic positions of the second-rung emission.

L. Schneebeli; M. Kira; S. W. Koch

2008-01-23

154

Characterization of Strong Light-Matter Coupling in Semiconductor Quantum-Dot Microcavities via Photon-Statistics Spectroscopy  

Microsoft Academic Search

It is shown that spectrally resolved photon-statistics measurements of the resonance fluorescence from realistic semiconductor quantum-dot systems allow for high contrast identification of the two-photon strong-coupling states. Using a microscopic theory, the second-rung resonance of Jaynes-Cummings ladder is analyzed and optimum excitation conditions are determined. The computed photon-statistics spectrum displays gigantic, experimentally robust resonances at the energetic positions of the

L. Schneebeli; M. Kira; S. W. Koch

2008-01-01

155

Latex Agglutination Test for Monitoring Antibodies to Avian Influenza Virus Subtype H5N1  

Microsoft Academic Search

Highly pathogenic avian influenza virus (AIV) subtype H5N1 emerged in Hong Kong in 1997 (2) and has since been threatening the poultry industry and human health worldwide. In the spring of 2004, avian influenza due to highly pathogenic subtype H5N1 spread throughout poultry populations in Asia and caused gigantic economic losses. Vaccination is a key strategy in the prevention and

Xiaojuan Xu; Meilin Jin; Zhengjun Yu; Hongchao Li; Dexin Qiu; Yadi Tan; Huanchun Chen

2005-01-01

156

Single cell analysis demonstrating somatic mosaicism involving 11p in a patient with paternal isodisomy and Beckwith-Wiedemann Syndrome  

Microsoft Academic Search

Beckwith-Wiedemann Syndrome (BWS) is characterized by numerous growth abnormalities including exomphalos, macroglossia, gigantism, and hemihypertrophy or hemihyperplasia. The {open_quotes}BWS gene{close_quotes} appears to be maternally repressed and is suspected to function as a growth factor or regulator of somatic growth, since activation of this gene through a variety of mechanisms appears to result in somatic overgrowth and tumor development. Mosaic paternal

F. Z. Bischoff; C. McCaskill; S. Subramanian

1994-01-01

157

The Oort cloud  

NASA Technical Reports Server (NTRS)

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

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

1991-01-01

158

construyendo dossier de prensa  

E-print Network

construyendo ciencia 365 días dossier de prensa #12;construyendo ciencia 365 días1. 365 días construyendo ciencia 2. Un gigante en marcha 3.Primera ciencia con GTC 4.Eficiencia en la observación 5. GTC capacidad empresarial, tecnológica y científica para acometer y desarrollar proyectos de "gran ciencia". Se

159

Macrodystrophia lipomatosa: four case reports  

PubMed Central

Aim Macrodystrophia lipomatosa is a rare cause of gigantism of limb which can be confused with other common causes like congenital lymphedema. It presents usually with loss of function and cosmetic problems. Four cases are described with emphasis on clinical presentation, differential diagnoses, imaging and treatment options. Methods & Results Four patients of macrodystrophia lipomatosa were thoroughly examined and subjected to investigations. Conclusion Besides diligent clinical examination, imaging and histopathology are crucial in clinching the diagnosis. PMID:20969776

2010-01-01

160

A case of a giant cystic lymphangioma mimicking acute appendicitis  

PubMed Central

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

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

2012-01-01

161

ARTICLE The island rule and the evolution of body size in the deep sea  

Microsoft Academic Search

Aim Our goal is to test the generality of the island rule - a graded trend from gigantism in small-bodied species to dwarfism in large-bodied species - in the deep sea, a non-insular but potentially analogous system. Location Shallow-water and deep-sea benthic habitats in the western Atlantic Ocean from the North to South Poles. Methods We conducted regression analyses of

Craig R. McClain; Alison G. Boyer; Gary Rosenberg

162

The Giant Jet  

NASA Astrophysics Data System (ADS)

Thunderstorm clouds may discharge directly to the ionosphere in spectacular luminous jets - the longest electric discharges on our planet. The electric properties of jets, such as their polarity, conductivity, and currents, have been predicted by models, but are poorly characterized by measurements. Here we present an analysis of the first gigantic jet that with certainty has a positive polarity. The jet region in the mesosphere was illuminated by an unusual sprite discharge generated by a positive cloud-to-ground lightning flash shortly after the onset of the jet. The sprite appeared with elements in a ring at ~40 km distance around the jet, the elements pointing curving away from the jet. This suggests that the field close the jet partially cancels the field driving the sprite. From a simple model of the event we conclude that a substantial portion of the positive cloud potential must be carried to ~50 km altitude, which is also consistent with the observed channel expansion and the electromagnetic radiation associated with the jet. It is further shown that blue jets are likely to substantially modify the free electron content in the lower ionosphere because of increased electron attachment driven by the jet electric field. The model further makes clear the relationship between jets, gigantic jets, and sprites. This is the first time that sprites are used for sounding the properties of the mesosphere. The observations presented here will allow evaluation of theories for jet and gigantic jet generation and of their influence on the atmosphere-ionosphere system.

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

2012-04-01

163

Low H/L of initial and secondary landslides on Mars Valles Marineris floor  

NASA Astrophysics Data System (ADS)

The Mars Global Surveyer (MGS) has investigated the almost whole Martian topography with high resolution and its products are reflected in the Google Earth's martian option. This digital service provide huge opportunities to public to view the preserved landslide topography as well as to measure the parameters for landslide mobility such as average coefficient of friction (H/L), and apparent friction angle. Among those views, the Valles Marineris is the most landslide prone area and a lot of long runout gigantic landslides can be extracted along the tectonic cliff. Authors encouraged undergraduate students to measure this parameter as an exercise of introductory course of planetary science, especially of the gigantic initial landslides to compare with those of secondary landslides which looks like induced by subsequent triggers such as earthquake or metor impact. Preliminary results show that (1) The H/L values of the gigantic initial landslides are dependent on landslide volume as reported by previous studies; (2) secondary landslides of much less volumes generally have wide and thin spread features but much smaller friction like debris flows. Those characters imply that those landslides might have been induced in the landslide deposits of higher moisture content and/or runout on valley floor of highly saturated or shallow ground water table.

Sagi, H.; Fukuoka, H.

2012-12-01

164

Bee communities (Hymenoptera: Anthophila) of the "Cerrado" ecosystem in São Paulo State, Brazil.  

PubMed

Five surveys of the bee communities in four "Cerrado" ecosystem reserves in São Paulo State were compared for species richness and similarity. These areas are fragment vegetation reser-ves located in the Cerrado Corumbataí Reserve (Corumbataí), Jataí Ecological Park (Luiz Antônio), Cajuru (Cajuru), and Vassununga State Park - "Gleba de Cerrado de Pé-de-Gigante" (Santa Rita do Passa Quatro). The methodology consisted of capturing bees foraging on flowers along transects, though with small differences between surveys. These "cerrado" areas have a large number of species of native bees, which are important pollinators in several Brazilian ecosystems. The community of bees varied among these different fragments. Based on 500 individuals (standardized by rarefaction), Cajuru, Corumbataí 1 and Corumbataí 2 were the areas with highest species richness, and Jataí and Pé-de-Gigante had the lowest species richness in the bee communities. The bee faunas of Corumbataí 2 and Pé-de-Gigante had the highest similarity, forming a group with the bee fauna of Cajuru. The bee faunas of Corumbataí 1 and Jataí were isolated from this group. We found that the bee species richness and similarity found in these "cerrado" areas cannot be explained by general factors such as the size of the fragment, the species richness of plants and the distance between the areas. Therefore, we suppose that local factors that differ among areas, such as interactions between populations, and competition and interference from surrounding areas influence and determine bee species richness and similarity in these reserves. PMID:19681028

Andena, S R; Nascimento, F S; Bispo, P C; Mechi, M R; Mateus, S; Bego, L R

2009-01-01

165

The Thinking Machine: A Physical Science Project  

NSDL National Science Digital Library

Science projects can be a wonderful opportunity for learning and creativity, or a gigantic headache for teachers. After several years of implementation, experience, and revision, the author has put together a fun and engaging project centered on machines that is appropriate for middle school students. This project came to be known simply as "The Thinking Machine Project," which draws its origin from the national Rube Goldberg Machine competition held each year at Purdue University. Here is one way to bring technology, writing, drawing, creativity, and hands-on ingenuity together in a single fun and successful project.

Amber Jarrard

2008-11-01

166

Chiral symmetry breaking in crystals of achiral polymers.  

PubMed

Many achiral polymers crystallize into spherulites with gigantic chirality, as is evident from spectacular images of periodic banding observed in a polarized optical microscope, arising from the twisting of the lamellae making up the spherulites. We present a new mechanism of the spontaneous chiral symmetry breaking, by accounting for topological defects in finite crystalline ribbons made of achiral molecules in equilibrium. We show that disclinations stabilize a twisted helicoidal ribbon, with spontaneous selection of its width and chiral period, which are proportional to each other, as a universal law. PMID:20867548

Hatwalne, Yashodhan; Muthukumar, M

2010-09-01

167

WUArchive: File Archive at Washington University in St. Louis  

NSDL National Science Digital Library

The gigantic and very popular FTP archive at Washington University at St. Louis (wuarchive) is available as a Web site, providing easy access for those who don't remember how to spell anonymous. Over 65 gigabytes of files in 11 top level directories (with literally hundreds of directories underneath) covering such topics as systems, graphics, documentation, selected Usenet News archives, and educational programs and materials. New is a list of the hundreds of sites wuarchive mirrors. Concentration is on computer related items, however see the public directory for an eclectic selection of files.

168

Giant Nernst and Hall effects due to chiral superconducting fluctuations  

NASA Astrophysics Data System (ADS)

We consider the Nernst and Hall effects in the fluctuation regime of chiral superconductors above transition temperatures, that are raised not by the conventional Lorentz force but by a mechanism that is an analog of the anomalous Nernst or Hall effects, i.e., asymmetric scattering due to chiral superconducting fluctuations. It is found that these effects can be gigantic for cleaner samples compared to conventional ones, exhibiting qualitatively distinct behavior. The results provide systematic and comprehensive understanding for recent experimental observations of the Nernst effect in a clean URu2Si2 sample, which is suggested to be a chiral superconductor.

Sumiyoshi, Hiroaki; Fujimoto, Satoshi

2014-11-01

169

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

PubMed

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

Kitanosono, Taku; Kobayashi, Sh?

2015-01-01

170

A nautical archaeological study of Kublai Khan's fleets  

E-print Network

, these ships were 40 chi (c. 12 m) long, 1 chan and 2 chi (c. 3. 6 m) wide, and 3 chi (c. 0. 9 m) deep. One example was composed of 223 planks, 24 pieces of bottom planks, 12 timbers for the bulkheads, 24 pieces of "wall pillars", 1 piece for the tiller... and those made in Fujian (Pao, 1961:40-41). The Guangdong ship was the general name for all ships built in Guangdong. The ha'-xian chuan (Gigantic Sea- eagle ship) of the Yuan dynasty and 1, 000-liao seagoing vessel of the Ming dynasty were examples...

Inoue, Takahiko

1991-01-01

171

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

NASA Technical Reports Server (NTRS)

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.

1980-01-01

172

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

NASA Astrophysics Data System (ADS)

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.

Gangopadhyay, Diya; Vasal, Ityam; Yammiyavar, Pradeep

173

Large meteorite impacts: The K/T model  

NASA Technical Reports Server (NTRS)

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.

Bohor, B. F.

1992-01-01

174

Molarization of Mandibular Second Premolar  

PubMed Central

ABSTRACT Macrodontia (megadontia, megalodontia, mac rodontism) is a rare shape anomaly that has been used to describe dental gigantism. Mandibular second premolars show an elevated variability of crown morphology, as are its eruptive potential and final position in the dental arch. To date, only eight cases of isolated macrodontia of second premolars have been reported in the literature. This case report presents clinical and radiographic findings of unusual and rare case of isolated unilateral molarization of left mandibular second premolar. How to cite this article: Mangla N, Khinda VIS, Kallar S, Brar GS. Molarization of Mandibular Second Premolar. Int J Clin Pediatr Dent 2014;7(2):137-139. PMID:25356014

Singh Khinda, Vineet Inder; Kallar, Shiminder; Singh Brar, Gurlal

2014-01-01

175

Growth hormone and its disorders  

PubMed Central

Growth hormone (GH) is synthesised and secreted by the somatotroph cells of the anterior lobe of the pituitary gland. Its actions involve multiple organs and systems, affecting postnatal longitudinal growth as well as protein, lipid, and carbohydrate metabolism. GH hypersecretion results in gigantism or acromegaly, a condition associated with significant morbidity and mortality, while GH deficiency results in growth retardation in children and the GH deficiency syndrome in adults. This article, aimed at non?paediatric physicians, examines the clinical features, diagnosis, and current concepts in the management of these conditions. PMID:16397076

Ayuk, J; Sheppard, M C

2006-01-01

176

Anomalous increase of the thermal emf in epitaxial graphene on size-quantized films  

NASA Astrophysics Data System (ADS)

The thermoelectric effect in epitaxial graphene formed on the surface of a size-quantized metal film is examined in the context of a Davydov model. An approach based on the Kubo formula for the conductivity and differential thermal emf is used. It is shown that because of size quantization, near the edges of the energy levels the thermal emf of epitaxial graphene increases to gigantic values of 200 ?V/K, or almost a factor of seven greater than the emf of isolated graphene (about 30 ?V/K).

Alisultanov, Z. Z.; Mirzegasanova, N. A.

2014-05-01

177

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)

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.

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

1992-01-01

178

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

NASA Astrophysics Data System (ADS)

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.

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

179

A Disintegrating Glacier  

NSDL National Science Digital Library

Recent satellite images have revealed two new icebergs floating off the Antarctic coast. The icy behemoths are fragments of the Ninnis Glacier. This NASA fact sheet uses text and remotely sensed imagery to describe the events of January 2000, in which a large tongue of the Ninnis Galcier broke off and split into two gigantic icebergs. The breakup of the Ninnis Glacier Tongue has important implications regarding the Antarctic Ice Sheet's potential response to global climate change and its effect on global sea level. Links to other related sites are also included.

2000-12-06

180

Macrodystrophia lipomatosa: four case reports  

Microsoft Academic Search

Aim  Macrodystrophia lipomatosa is a rare cause of gigantism of limb which can be confused with other common causes like congenital\\u000a lymphedema. It presents usually with loss of function and cosmetic problems. Four cases are described with emphasis on clinical\\u000a presentation, differential diagnoses, imaging and treatment options.\\u000a \\u000a \\u000a \\u000a \\u000a Methods & Results  Four patients of macrodystrophia lipomatosa were thoroughly examined and subjected to investigations.

Rizwan A Khan; Shagufta Wahab; Ibne Ahmad; Rajendra S Chana

2010-01-01

181

On the origin of rare earth magnetostriction in compounds of perovskite-type structure  

NASA Astrophysics Data System (ADS)

It has been shown that a gigantic rare earth magnetostriction is possible in a perovskite-type structure as well as in a garnet structure. Numerical calculations of multipole moments of the rare earth ion have allowed us to predict the directions of maximum values of magnetostriction in dysprosium aluminate. Measurements confirm the highly anisotropic character of magnetostriction in rare earth compounds of perovskite-type structure and show that the rare earth magnetostriction of compounds with different structures (garnets, perovskites) is determined mainly by the rare earth ion and not by their structures.

Kolmakova, N. P.; Krynetskii, I. B.

1994-02-01

182

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

NASA Astrophysics Data System (ADS)

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.

Larionov, Sergei; Loskutov, Alexander; Ryadchenko, Eugeny

2008-03-01

183

Upward electrical discharges observed above Tropical Depression Dorian  

NASA Astrophysics Data System (ADS)

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.

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

2015-01-01

184

Upward electrical discharges observed above Tropical Depression Dorian.  

PubMed

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

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

2015-01-01

185

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

PubMed

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

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

2013-05-15

186

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

NASA Astrophysics Data System (ADS)

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.

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

2009-09-01

187

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

PubMed

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

Tanaka, H K M; Watanabe, H

2014-01-01

188

Probing the extreme wind confinement of the most magnetic O star with COS spectroscopy  

NASA Astrophysics Data System (ADS)

We propose to obtain phase-resolved UV spectroscopy of the recently discovered magnetic O star NGC 1624-2, which has the strongest magnetic field ever detected in a O-star, by an order of magnitude. We will use the strength and variability of the UV resonance line profiles to diagnose the density, velocity, and ionization structure of NGC 1624-2's enormous magnetosphere that results from entrapment of its stellar wind by its strong, nearly dipolar magnetic field. With this gigantic magnetosphere, NGC 1624-2 represents a new regime of extreme wind confinement that will constrain models of magnetized winds and their surface mass flux properties. A detailed understanding of such winds is necessary to study the rotational braking history of magnetic O-stars, which can shed new light on the fundamental origin of magnetism in massive, hot stars.

Petit, Veronique

2014-10-01

189

Quantum renormalization of the spin Hall effect.  

PubMed

By quantum Monte Carlo simulation of a realistic multiorbital Anderson impurity model, we study the spin-orbit interaction (SOI) of an Fe impurity in Au host metal. We show, for the first time, that the SOI is strongly renormalized by the quantum spin fluctuation. Based on this mechanism, we can explain why the gigantic spin Hall effect in Au with Fe impurities was observed in recent experiments, while it is not visible in the anomalous Hall effect. In addition, we show that the SOI is strongly renormalized by the Coulomb correlation U. Based on this picture, we can explain past discrepancies in the calculated orbital angular momenta for an Fe impurity in an Au host. PMID:20868117

Gu, Bo; Gan, Jing-Yu; Bulut, Nejat; Ziman, Timothy; Guo, Guang-Yu; Nagaosa, Naoto; Maekawa, Sadamichi

2010-08-20

190

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

NASA Astrophysics Data System (ADS)

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.

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

2014-04-01

191

Turnaround in cyclic cosmology.  

PubMed

It is speculated how dark energy in a brane world can help reconcile an infinitely cyclic cosmology with the second law of thermodynamics. A cyclic model is described, in which dark energy with w<-1 equation of state leads to a turnaround at a time, extremely shortly before the would-be big rip, at which both volume and entropy of our Universe decrease by a gigantic factor, while very many independent similarly small contracting universes are spawned. The entropy of our model decreases almost to zero at turnaround but increases for the remainder of the cycle by a vanishingly small amount during contraction, empty of matter, then by a large factor during inflationary expansion. PMID:17359014

Baum, Lauris; Frampton, Paul H

2007-02-16

192

Proteus syndrome.  

PubMed

Proteus syndrome is a rare sporadic, hamartoneoplastic disorder of vascular, skeletal, and soft tissues that causes asymmetry of the skull, body, arms, and the legs. The name "Proteus" of the Greek god who had the ability to change his shape was coined to define the variety of deformities including partial gigantism of the hands or feet, asymmetry of the arms and legs, hypertrophy of long bones, plantar hyperplasia, haemangiomas, lipomas, varicosities, linear verrucous epidermal naevi, macrocephaly, and cranial hyperostoses. The basic defect seems to be the focal overgrowth of cellular elements in skin, bone, and other connective tissues. The variable features of the syndrome make differential diagnosis challenging for clinicians. The most important features are the hamartomatous disorders. The long-term prognosis is still not clear. As it is a hamartoneoplastic and incompletely delineated syndrome, the patients must be followed up because of the possible risk of neoplasms. PMID:14649692

Bilkay, Ufuk; Tokat, Cenk; Ozek, Cuneyt; Gundogan, Hakan; Erdem, Ozgur; Gurler, Tahir; Cagdas, Arman

2003-01-01

193

Mass extinctions and cosmic collisions - A lunar test  

NASA Technical Reports Server (NTRS)

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.

Horz, F.

1985-01-01

194

A basal dromaeosaurid and size evolution preceding avian flight.  

PubMed

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

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

2007-09-01

195

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

USGS Publications Warehouse

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.

Rader, Jonathan A.; Dillon, Michael E.; Chesser, Terry; Sabat, Pablo; Martinez del Rio, Carlos

2015-01-01

196

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

PubMed

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

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

2014-01-01

197

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

NASA Astrophysics Data System (ADS)

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.

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

2014-04-01

198

Macrodystrophia lipomatosa of foot involving great toe.  

PubMed

Macrodystrophia lipomatosa is a rare form of congenital disorder in which there is localized gigantism characterized by progressive overgrowth of all mesenchymal elements with a disproportionate increase in the fibroadipose tissues. The adipose tissue infiltration involves subcutaneous tissue, periosteum, nerves and bone marrow. Most of the cases reported have hand or foot involvement. Patient seeks medical help for improving cosmesis or to get the size of the involved part reduced in order to reduce mechanical problems. We report a case of macrodystrophia lipomatosa involving medial side of foot with significant enlargement of great toe causing concern for cosmesis and inconvenience due to mechanical problems. The X-rays showed increased soft tissue with more of adipose tissue and increased size of involved digits with widening of ends. Since the patient's mother did not want any surgical intervention he was educated about foot care and proper footwear design was suggested. PMID:24703060

Gaur, A K; Mhambre, A S; Popalwar, H; Sharma, R

2014-06-01

199

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

PubMed

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

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

2014-05-23

200

3DScapeCS: application of three dimensional, parallel, dynamic network visualization in Cytoscape  

PubMed Central

Background The exponential growth of gigantic biological data from various sources, such as protein-protein interaction (PPI), genome sequences scaffolding, Mass spectrometry (MS) molecular networking and metabolic flux, demands an efficient way for better visualization and interpretation beyond the conventional, two-dimensional visualization tools. Results We developed a 3D Cytoscape Client/Server (3DScapeCS) plugin, which adopted Cytoscape in interpreting different types of data, and UbiGraph for three-dimensional visualization. The extra dimension is useful in accommodating, visualizing, and distinguishing large-scale networks with multiple crossed connections in five case studies. Conclusions Evaluation on several experimental data using 3DScapeCS and its special features, including multilevel graph layout, time-course data animation, and parallel visualization has proven its usefulness in visualizing complex data and help to make insightful conclusions. PMID:24225050

2013-01-01

201

Cloud Formation and Water Transport on Mars after Major Outflow Events  

NASA Technical Reports Server (NTRS)

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?

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

2012-01-01

202

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

NASA Technical Reports Server (NTRS)

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.

Haekkinen, Sirpa

2000-01-01

203

Mars: Volcanism in the Valles Marineris overlooked  

NASA Technical Reports Server (NTRS)

Do volcanic rocks exist in the Valles Marineris. This question is pertinent because the Valles Marineris are gigantic grabens, rivaling rift valleys on earth in size and depth. The Valles Marineris were interpreted as extensional tectonic structures, perhaps incipient rifts. On earth, rift valleys commonly contain volcanic deposits. On Mars, deposits inside the Valles Marineris grabens do not have the morphologic signature of such easily identified volcanic features as shield volcanoes or lava flows. Therefore, many researchers have not recognized the deposits inside the Valles Marineris as volcanic. Is Mars, then, different from earth in having formed riftlike grabens unaccompanied by volcanism. Overall, results from the study suggest that volcanism was present in the Valles Marineris; the volcanism was explosive in places; some volcanism was more felsic than that generally assumed elsewhere; and the younger sequence of interior beds was emplaced so late in Martian history that the planet may be considered to be still volcanically active.

Lucchitta, B. K.

1988-01-01

204

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

PubMed

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

Semenza, Jan C

2003-09-01

205

Unravelling the determinants of insular body size shifts  

PubMed Central

The island rule, a pattern of size shifts on islands, is an oft-cited but little understood phenomenon of evolutionary biology. Here, we explore the evolutionary mechanisms behind the rule in 184 mammal species, testing climatic, ecological and phylogenetic hypotheses in a robust quantitative framework. Our findings confirm the importance of species’ ecological traits in determining both the strength and the direction of body size changes on islands. Although the island rule pattern appears relatively weak overall, we find strongest support for models incorporating trait, climatic and geographical factors in a phylogenetic context, lending support to the idea that the island rule is a complex phenomenon driven by interacting intrinsic and extrinsic mechanisms. Overall, we find that different clades may be evolutionarily predisposed to dwarfism or gigantism, but the magnitude of size changes depends more on adaptation to the novel island environment. PMID:23234863

McClain, Craig R.; Durst, Paul A. P.; Boyer, Alison G.; Francis, Clinton D.

2013-01-01

206

Mechanism of enhanced optical second-harmonic generation in the conducting pyrochlore-type Pb2Ir2O7-x oxide compound.  

PubMed

The structural, electronic, and optical properties of pyrochlore-type Pb(2)Ir(2)O(6)O(0.55)('), which is a metal without spatial inversion symmetry at room temperature, were investigated. Structural analysis revealed that the structural distortion relevant to the breakdown of the inversion symmetry is dominated by the Pb-O' network but is very small in the Ir-O network. At the same time, gigantic second-harmonic generation signals were observed, which can only occur if the local environment of the Ir 5d electrons features broken inversion symmetry. First-principles electronic structure calculations reveal that the underlying mechanism for this phenomenon is the induction of the noncentrosymmetricity in the Ir 5d bands by the strong hybridization with O' 2p orbitals. Our results stimulate theoretical study of inversion-broken iridates, where exotic quantum states such as a topological insulator and Dirac semimetal are anticipated. PMID:23683242

Hirata, Yasuyuki; Nakajima, Makoto; Nomura, Yusuke; Tajima, Hiroyuki; Matsushita, Yoshitaka; Asoh, Keiko; Kiuchi, Yoko; Eguiluz, Adolfo G; Arita, Ryotaro; Suemoto, Tohru; Ohgushi, Kenya

2013-05-01

207

Monster of the Milky Way  

NSDL National Science Digital Library

This NOVA television broadcast discusses black holes and presents new research indicating that a supermassive black hole may lurk at the center of our own galaxy. Features include interviews with researchers who explain the basics of black holes and reveal why they think the Milky Way may harbor a gigantic black hole at its center, and audio clips of physicists and astronomers describing their ideas about black holes. A slide show explains the process by which particularly massive stars consume their nuclear fuel, explode in a supernova, and collapse to an unimaginably dense point called a singularity. There is also a program preview and transcript, as well as an interactive catalog of other astronomical objects.

208

A Graph Summarization Algorithm Based on RFID Logistics  

NASA Astrophysics Data System (ADS)

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.

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

209

Familial Dandy-Walker malformation and leukodystrophy.  

PubMed

We report the first familial cases with two different types of posterior fossa cystic malformation and a leukodystrophic-like aspect on cerebral magnetic resonance imaging (MRI). The girl and her brother had severe encephalopathy, marked hypotonia, absent deep tendon reflexes, macrocrania, gigantism, and dysmorphic face and extremities. The girl had generalized seizures. The boy had unilateral cataract and bilateral optic atrophy. The parents were first cousins, suggesting autosomal recessive transmission. MRI showed Dandy-Walker variant in the girl, with cerebellar vermis hypoplasia and expansion of the cisterna magna, which communicated with the fourth ventricle. Her brother had mega cisterna magna communicating with the fourth ventricle and a normal cerebellum. The 2 children had abnormally high signal in the supratentorial white matter. Visual and auditory evoked potentials revealed prolonged latencies. Motor and sensory conduction velocities were normal. Muscle and nerve biopsies were normal. Metabolic exploration demonstrated no abnormality. PMID:9258968

Humbertclaude, V T; Coubes, P A; Leboucq, N; Echenne, B B

1997-05-01

210

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

PubMed Central

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

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

2007-01-01

211

Markets and technology needs for UHB-LEDs  

NASA Astrophysics Data System (ADS)

With an annual volume of more than 5 million units of 2" equivalent substrates, GaN-based LED is the main eater of nitride materials targeting a 3.5B market at devices level. The next big challenge for LED business is to take market shares over the general lighting industry and dollar per lumen (/lm) ratio is the key parameter. Numerous technological improvements are under investigation: - At die level, photonic crystals and surface texturing technologies are jointly developed to increase the light extraction. External Quantum Efficiency EQE has now reached > 75% at R&D level. - At material level, there is a rapid emergence of new substrates for GaN epitaxy and composite substrates in 6" diameter. That is opening new doors to higher LED luminous efficiency and cost reduction toward the gigantic SSL general illumination business.

Roussel, Philippe

2007-09-01

212

Magnetic Transitions of Multiferroic Frustrated Magnets Revealed by Resonant Soft X-ray Magnetic Scattering  

NASA Astrophysics Data System (ADS)

The coexistence of magnetism and ferroelectricity with cross coupling, termed multiferroicity, rarely occurs. The discovery of gigantic magnetoelectric coupling in frustrated magnets has revived interest in their multiferroic behavior. Here, we review the measurements of resonant soft-X-ray magnetic scattering in the multiferroic frustrated magnets TbMn2O5, LiCu2O2, and CoCr2O4. In addition to the experimental technique used, the evolution of the wave vector of magnetic ordering about the temperature of multiferroic transitions is discussed. We proffer scattering evidence of multiferroicity and a pathway for understanding the intricate coupling between magnetism and ferroelectricity in magnets with spin spirals. Our results also reveal the low-dimension nature of a quantum spin-chain multiferroics and the evolution of the interrelation between the polarization P, the magnetization M, and the spiral wave vector Q.

Huang, Di-Jing; Okamoto, Jun; Huang, Shih-Wen; Mou, Chung-Yu

2010-01-01

213

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

PubMed

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

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

2002-12-01

214

A review of the osteopetroses.  

PubMed Central

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

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

1977-01-01

215

Intérêt biochronologique des Kubanochoerinae (Mammalia, Suidae) et étude de nouveaux restes de Megalochoerus khinzikebirus et Libycochoerus massai du KenyaThe biochronological importance of Kubanochoerine (Mammalia, Suidae), together with a description of new material of Megalochoerus khinzikebirus and Libycochoerus massai from Kenya  

NASA Astrophysics Data System (ADS)

Kubanochoerine suids underwent such rapid increase in size from Early to Middle Miocene times that they can be used for biochronology. Megalochoerus khinzikebirus, a gigantic suid occurs at Gebel Zelten, Libya, and at two sites in Kenya dated about 15 Ma. Even larger suids of the same lineage ( Megalochoerus homungous) are known from younger deposits in Kenya, Pakistan, Libya and Turkey. The smaller species, Megalochoerus marymuunguae occurs in earlier strata in Kenya (ca 17.2 Ma) and it is, in its turn, larger than older species such as Libycochoerus jeanneli (17-17.8 Ma), Kenyasus rusingensis (17.8 Ma) and Nguruwe kijivium (ca 20 Ma) from East Africa. A record of Libycochoerus massai from the Tugen hills, Kenya (ca 15.5 Ma) provides further evidence in support of the usefulness of this lineage for geochronology.

Pickford, Martin

2001-02-01

216

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

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

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

217

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

PubMed Central

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

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

2014-01-01

218

The Volcano Adventure Guide  

NASA Astrophysics Data System (ADS)

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.

Goff, Fraser

2005-05-01

219

Introduction to Plasma Dynamo, Reconnection and Shocks  

SciTech Connect

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.

Intrator, Thomas P. [Los Alamos National Laboratory

2012-08-30

220

Lead in ancient Rome’s city waters  

PubMed Central

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

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

2014-01-01

221

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

PubMed Central

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

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

2014-01-01

222

Lead in ancient Rome's city waters.  

PubMed

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

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

2014-05-01

223

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

PubMed

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

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

2014-08-01

224

Crossing the line: increasing body size in a trans-Wallacean lizard radiation (Cyrtodactylus, Gekkota).  

PubMed

The region between the Asian and Australian continental plates (Wallacea) demarcates the transition between two differentiated regional biotas. Despite this striking pattern, some terrestrial lineages have successfully traversed the marine barriers of Wallacea and subsequently diversified in newly colonized regions. The hypothesis that these dispersals between biogeographic realms are correlated with detectable shifts in evolutionary trajectory has however rarely been tested. Here, we analyse the evolution of body size in a widespread and exceptionally diverse group of gekkotan lizards (Cyrtodactylus), and show that a clade that has dispersed eastwards and radiated in the Australopapuan region appears to have significantly expanded its body size 'envelope' and repeatedly evolved gigantism. This pattern suggests that the biotic composition of the proto-Papuan Archipelago provided a permissive environment in which new colonists were released from evolutionary constraints operating to the west of Wallacea. PMID:25296929

Oliver, Paul M; Skipwith, Phillip; Lee, Michael S Y

2014-10-01

225

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

NASA Technical Reports Server (NTRS)

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.

Zheng, Yihua

2010-01-01

226

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

NASA Technical Reports Server (NTRS)

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.

Zheng, Yihua

2011-01-01

227

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

NASA Astrophysics Data System (ADS)

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

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

2014-10-01

228

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

PubMed

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

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

2014-01-24

229

Macrodystrophia Lipomatosa: Radiologic-Pathologic Correlation  

PubMed Central

Macrodystrophia lipomatosa (MDL) is a rare cause of congenital macrodactyly, characterised by progressive proliferation of all mesenchymal elements, with disproportionate increase in fibro-adipose tissue. It occurs most frequently in lower limbs along the distribution of the medial plantar nerve. MDL presents as localised gigantism of the hand or foot and comes to clinical attention for cosmetic reasons, mechanical problems secondary to degenerative joint disease, or development of neurovascular compression. Here, we report a case of MDL, with altered soft tissue growth due to an earlier surgery, making clinical diagnosis difficult. However, with a complete radio-clinical work-up and review of the history, a provisional diagnosis of MDL was made, which was confirmed by histopathology and during surgery. PMID:21966615

Upadhyay, Deepika; Parashari, Umesh C; Khanduri, Sachin; Bhadury, Samarjit

2011-01-01

230

Acoustic field enhancement and subwavelength imaging by coupling to slab waveguide modes  

NASA Astrophysics Data System (ADS)

We present a theoretical study on the amplification of evanescent sound waves produced by coupling to trapped modes hosted by a fluidic planar waveguide. Total internal reflection at interfaces of different refractive indexes can be frustrated by the introduction of a slow slab waveguide which is leading to a gigantic field enhancement, useful for sensitive transducers and acoustic shock lithotripsy. The mechanism behind the evanescent field coupling that is also known as tunnelling barrier penetration in quantum mechanics is here adopted for its use in an acoustic superlens. The higher spatial harmonics produced by a subwavelength object can couple to trapped modes of the slow waveguide and be reproduced as an image at a distant plane. We suggest a practical implementation of these ideas by means of a silicone rubber slab containing positive acoustic wave propagation parameters.

Christensen, J.; García de Abajo, F. J.

2010-10-01

231

MoMA: The Changing of the Avant-Garde  

NSDL National Science Digital Library

This Web exhibition from MoMA presents a history of modern utopian and visionary architecture, using architectural drawings donated to the museum by the Howard Gilman Foundation in 2000. The drawings date from the late 1950s to the 1970s. The main menu is two spheres, Megastructures (larger, public buildings and complexes) and Postmodern Roots (smaller buildings, retail and houses), from which users can select names to view particular projects. Each project consists of two to four drawings and explanatory text, with larger views of all the drawings available. An interesting example under Megastructures is Superstudio, a group of five Italian architects who, in the 1960s, created a set of purely theoretical drawing that impose gigantic, white, grid-patterned structures on natural landscapes such as rivers, ocean coastlines, and the Alps. Megastructures give way to Postmodern Roots in the 1960s, where drawings of projects by Robert Venturi, Michael Graves, James Stirling, Rem Koolhaas, and others can be seen.

2002-01-01

232

Acromegaly said to respond to proton therapy  

SciTech Connect

A news article is presented which discusses a new use for proton therapy. As physicians and physicists continue to refine the clinical applications for charged particles, they can point to at least one notable success story: the treatment of acromegaly, a disorder that afflicts an estimated 250 persons in the United States each year. Bernard Kliman, MD, reported at the annual Endocrine Society meeting in Indianapolis that his group at Harvard Medical School, Boston, and the Harvard cyclotron has cured 479 (85.5%) of 560 patients with acromegaly or gigantism. Cure is defined as reducing growth hormone level to less than 5 ..mu..g/L and shrinking the soft tissue growth characteristic of the disease.

Raymond, C.A.

1988-02-12

233

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

NASA Astrophysics Data System (ADS)

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

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

2012-12-01

234

Is IGSF1 involved in human pituitary tumor formation?  

PubMed

IGSF1 is a membrane glycoprotein highly expressed in the anterior pituitary. Pathogenic mutations in the IGSF1 gene (on Xq26.2) are associated with X-linked central hypothyroidism and testicular enlargement in males. In this study, we tested the hypothesis that IGSF1 is involved in the development of pituitary tumors, especially those that produce growth hormone (GH). IGSF1 was sequenced in 21 patients with gigantism or acromegaly and 92 healthy individuals. Expression studies with a candidate pathogenic IGSF1 variant were carried out in transfected cells and immunohistochemistry for IGSF1 was performed in the sections of GH-producing adenomas, familial somatomammotroph hyperplasia, and in normal pituitary. We identified the sequence variant p.N604T, which in silico analysis suggested could affect IGSF1 function, in two male patients and one female with somatomammotroph hyperplasia from the same family. Of 60 female controls, two carried the same variant and seven were heterozygous for other variants. Immunohistochemistry showed increased IGSF1 staining in the GH-producing tumor from the patient with the IGSF1 p.N604T variant compared with a GH-producing adenoma from a patient negative for any IGSF1 variants and with normal control pituitary tissue. The IGSF1 gene appears polymorphic in the general population. A potentially pathogenic variant identified in the germline of three patients with gigantism from the same family (segregating with the disease) was also detected in two healthy female controls. Variations in IGSF1 expression in pituitary tissue in patients with or without IGSF1 germline mutations point to the need for further studies of IGSF1 action in pituitary adenoma formation. PMID:25527509

Faucz, Fabio R; Horvath, Anelia D; Azevedo, Monalisa F; Levy, Isaac; Bak, Beata; Wang, Ying; Xekouki, Paraskevi; Szarek, Eva; Gourgari, Evgenia; Manning, Allison D; de Alexandre, Rodrigo Bertollo; Saloustros, Emmanouil; Trivellin, Giampaolo; Lodish, Maya; Hofman, Paul; Anderson, Yvonne C; Holdaway, Ian; Oldfield, Edward; Chittiboina, Prashant; Nesterova, Maria; Biermasz, Nienke R; Wit, Jan M; Bernard, Daniel J; Stratakis, Constantine A

2015-02-01

235

Dinámica y crecimiento de los granos de polvo en la nebulosa protoplanetaria  

NASA Astrophysics Data System (ADS)

En el escenario estándar de la formación planetaria, los planetesimales (cuerpos de tamaño kilométrico) crecen a partir de granos de polvo, similares a los interestelares, embebidos en un disco gaseoso denominado nebulosa protoplanetaria. Durante esta etapa, los movimientos del gas pueden tener gran influencia en la dinámica y el crecimiento de los granos de polvo, dado que el flujo kepleriano del gas frena el movimiento de los mismos haciendo que caigan hacia el Sol, y la turbulencia inhibe la inestabilidad gravitacional de la capa de polvo. Aunque se acepta que los planetesimales fueron los elementos constituyentes de los planetas, todavía se desconoce cómo se produjo la formación de los mismos. Por esta razón, en los estudios más recientes, existe un renovado interés por comprender mejor la evolución de la capa de polvo inmersa en el disco gaseoso de la Nebulosa. El gas que fluye en el disco puede engendrar estructuras carentes de simetría axial, como por ejemplo ondas espirales y vórtices, a partir de gran variedad de mecanismos de excitación e inestabilidad. En 1995, Barge y Sommeria pusieron de manifiesto que la existencia de vórtices gaseosos persistentes en la nebulosa solar tendría importantes consecuencias sobre la formación de los planetesimales y el posterior crecimiento de los planetas gigantes. La investigación desarrollada en esta Tesis analiza la relación entre el polvo y el gas debida al acoplamiento por fricción dinámica entre ambos; en concreto, se estudia el efecto del flujo medio del gas sobre la dinámica de las partículas de polvo. El primer objetivo es investigar en profundidad los procesos de captura y crecimiento de los granos de polvo dentro de un vórtice y su posible relevancia en cuanto a la formación de los planetesimales. El segundo objetivo es la exploración de los efectos de ondas espirales propagándose en el disco gaseoso sobre la dinámica y el crecimiento de las partículas. La presencia de líneas de corriente no circulares perturba significativamente el movimiento de las partículas alrededor del Sol e incrementa su vida media en la Nebulosa. El flujo medio del gas se modela de forma simple, analizándose la dinámica y el crecimiento de las partículas mediante simulaciones numéricas. Al incrementarse la vida media y la densidad superficial de las partículas sólidas, los mecanismos de confinamiento derivados de la presencia de vórtices y ondas espirales actuan sobre el material sólido de la Nebulosa (mediante agregación colisional o inestabilidades gravitacionales) de manera mucho más eficiente que la previamente considerada. Esto ofrece nuevas posibilidades para la formación de planetesimales y núcleos de planetas gigantes, y puede explicar la formación rápida de planetas extrasolares gigantes. Además, esta Tesis analiza la respuesta de las partículas, en un disco protoplanetario con un radio de 100 UA en torno a una estrella de tipo solar, al campo gravitatorio derivado de la presencia de dos estrellas compañeras ligadas en una órbita relativamente elongada (300-1600 UA). Para llevar a cabo este análisis, se han realizado una serie de simulaciones numéricas de configuraciones jerárquicas coplanares utilizando un programa FORTRAN que integra directamente las ecuaciones del movimiento con el objeto de modelar la presencia de las fuerzas gravitacionales y viscosas. El disco protoplanetario masivo se encuentra en torno a una de las componentes de la binaria. La evolución temporal del subdisco de polvo depende directamente de la naturaleza (directa o retrógrada) de la revolución relativa de la compañera estelar, y de la temperatura y la masa del disco circunestelar.

de La Fuente Marcos, Carlos

2001-06-01

236

Analysis of impulse signals with Hylaty ELF station  

NASA Astrophysics Data System (ADS)

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.

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

2012-04-01

237

Dynamics of Positive and Negative Streamers in Weak Uniform Electric Fields Between Thunderstorm Tops and the Lower Ionosphere  

NASA Astrophysics Data System (ADS)

It is well established by now that transient luminous events (TLEs) observed at different altitudes above thunderstorms commonly consist of large numbers of needle-shaped filaments of ionization, called streamers [e.g., Gerken and Inan, JASTP, 65, 567, 2003; Su et al., Nature, 423, 974, 2003; Pasko, Nature, 423, 927, 2003; and references cited therein]. One of the important questions of the current TLEs research, which directly relates to the evaluation of the total volumes of atmosphere affected by these phenomena and possible role of some of the TLEs (i.e., sprites, jets and gigantic jets) in establishing a direct path of electrical contact between the tropospheric and mesospheric/lower ionospheric regions, is related to the determination of the minimum electric fields required for the propagation of streamers in air at different pressures [Pasko and George, JGR, 107, 1458, 2002]. The minimum field required for the propagation of positive streamers in air at ground pressure has been extensively documented experimentally and usually stays close to the value 4.4 kV/cm [Allen and Ghaffar, J. Phys. D Appl. Phys., 28, 331, 1995], in agreement with recent results of numerical simulations of positive streamers [Babaeva and Naidis, IEEE Trans. Plasma Sci., 25, 375, 1997; Morrow and Lowke, J. Phys. D Appl. Phys., 30, 614, 1997]. The information about the absolute value of the similar field for the negative streamers at present is very limited. The existing sources indicate that this field is a factor of 2-3 higher than the corresponding field for the positive streamers [e.g., Raizer, Gas Discharge Physics, 1991, p. 361; Babaeva and Naidis, 1997]. We note that although from the streamer similarity laws one generally would expect the minimum fields required for streamer propagation to scale with altitude proportionally to the air neutral density N, the actual scaling for the altitude range of sprites, jets and gigantic jets has not yet been verified experimentally, and a limited amount of data currently available in the literature [Griffiths and Phelps, Q.J.R. Meteorol. Soc., 102, 419, 1976; Bazelyan and Raizer, Spark Discharge, 1998, p. 216] indicate possible deviations from the N scaling. In this talk we will discuss conditions required for the propagation of streamers in air at different pressures and will present corresponding results from a new two-dimensional model, which has recently been developed at Penn State for studies of dynamics of streamers in weak uniform electric fields, documenting the minimum electric field magnitudes required for the propagation of positive and negative streamers at TLE altitudes.

Liu, N.; Pasko, V. P.

2003-12-01

238

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

PubMed Central

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

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

2010-01-01

239

Rheological profile of the Tohoku-oki interplate megathrust across the source region of the M9 great earthquake  

NASA Astrophysics Data System (ADS)

Before attacked by the 2011 Tohoku-oki Earthquake (M9.0), large earthquakes off the Pacific coast of NE Japan had been believed to occur at specific areas, named asperities, on the subducting plate interface. In the NE Japan subduction zone, a typical asperity was found offshore of Miyagi Prefecture (Miyagi-oki), where M7-class earthquakes occurred in 1936, 1978, and 2005, with recurrence intervals of 37 years. However, the M9 gigantic earthquake occurred at the up-dip side of the asperity of the M7-class Miyagi-oki earthquakes. The large slips at the M9 event have been differently explained by different numerical models due to the lack of our knowledge on frictional properties and stress states at the plate interface. Here we constrain the stress states on the NE Japan interplate megathrust from a viewpoint of rock rheology. A strength profile of the megathrust was constructed across the source region of the M9 Tohoku-oki earthquake using laboratory data of friction, fracturing and ductile flow. Rheological properties of siliceous sedimentary rocks and subducting seamounts at the top of the oceanic plate were represented by those of wet quartz and gabbro, respectively. Depth-dependent changes of pressure, temperature, and pore pressure ratio were incorporated into the model. The frictional strength of the thrust fault was estimated to be about 150 MPa at the hypocenter of the M9 earthquake, which is located 17-18 km below the sea level. The large coseismic slips observed at the M9 event are explained by the large difference in fault strength between the shallow tsunami-genic zone and the M9 hypocentral zone. A large stress drop induced by a collapse of a subducted seamount possibly triggered the gigantic earthquake. At the deep (>35 km) part of the thrust fault, where M7-class Miyagi-oki earthquakes repeatedly occurred, siliceous rocks become ductile whereas gabbroic rocks are brittle and strong. Thus, the asperity of the M7-class earthquakes is considered as a broken seamount, which is surrounded by siliceous sedimentary rocks. A conditionally stable nature of the surrounding region is explained by frictional behaviors of quartz in the brittle-ductile transition zone. In contrast to the deep M7-class asperity, the M9 asperity (i.e., a region that was strongly coupled before the M9 Tohoku-oki earthquake) occupies a large part of the plate interface because shear strength is relatively insensitive to rock types at the intermediate depth. The along-arc extension of the M9 asperity is possibly constrained by fluid distributions on the plate interface.

Shimizu, I.

2013-12-01

240

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

PubMed Central

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

Li, Chunyi; McMahon, Chris

2013-01-01

241

An improved distance matrix computation algorithm for multicore clusters.  

PubMed

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

Al-Neama, Mohammed W; Reda, Naglaa M; Ghaleb, Fayed F M

2014-01-01

242

Galaxy Mass Assembly with VLT & HST and lessons for E-ELT/MOSAIC  

E-print Network

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-spect...

Hammer, F; Puech, M

2014-01-01

243

New color images of transient luminous events from dedicated observations on the International Space Station  

NASA Astrophysics Data System (ADS)

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.

Yair, Yoav; Rubanenko, Lior; Mezuman, Keren; Elhalel, Gal; Pariente, Meidad; Glickman-Pariente, Maya; Ziv, Baruch; Takahashi, Yukihiro; Inoue, Tomohiro

2013-09-01

244

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

NASA Technical Reports Server (NTRS)

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

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

2004-01-01

245

When did Carcharocles megalodon become extinct? A new analysis of the fossil record.  

PubMed

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

Pimiento, Catalina; Clements, Christopher F

2014-01-01

246

Control of Regional and Global Weather  

E-print Network

Author suggests and researches a new revolutionary idea for regional and global weather control. He offers to cover cities, bad regions of country, full country or a continent by a thin closed film with control clarity located at a top limit of the Earth troposphere (4 - 6 km). The film is supported at altitude by small additional atmospheric pressure and connected to ground by thin cables. It is known, the troposphere defines the Earth weather. Authors show this closed dome allows to do a full control of the weather in a given region (the day is always fine, the rain is only in night, no strong wind). The average Earth (white cloudy) reflectance equal 0.3 - 0.5. That means the Earth losses about 0.3 - 0.5 of a solar energy. The dome controls the clarity of film and converts the cold regions to subtropics and creates the hot deserts, desolate wildernesses to the prosperous regions with temperate climate. That is a realistic and the cheapest method of the weather control in the Earth at the current time. Key words: Global weather control, gigantic film dome, converting a cold region to subtropics, converting desolate wilderness to a prosperous region.

Alexander Bolonkin

2007-01-09

247

Wireless wearable controller for upper-limb neuroprosthesis.  

PubMed

The objective of this project was to develop a wireless, wearable joint angle transducer to enable proportional control of an upper-limb neuroprosthesis by wrist position. Implanted neuroprostheses use functional electrical stimulation to provide hand grasp to individuals with tetraplegia. Wrist position is advantageous for control because it augments the tenodesis grasp and can be implemented bilaterally. Recently developed, fully implantable multichannel stimulators are battery-powered and use wireless telemetry to control stimulator outputs. An external wrist controller was designed for command signal acquisition for people with cervical-level spinal cord injury to control this implantable stimulator. The wearable controller, which uses gigantic magnetoresistive sensing techniques to measure wrist position, is worn on the forearm. A small dime-sized magnet is fixed to the back of the hand. Results indicate that the device is a feasible control method for an upper-limb neuroprosthesis and could be reduced to a small "wristwatch" size for cosmesis and easy donning. PMID:19533538

Wheeler, Christa A; Peckham, P Hunter

2009-01-01

248

Genome Evolution by Matrix Algorithms: Cellular Automata Approach to Population Genetics  

PubMed Central

Mammalian genomes are replete with millions of polymorphic sites, among which those genetic variants that are colocated on the same chromosome and exist close to one another form blocks of closely linked mutations known as haplotypes. The linkage within haplotypes is constantly disrupted due to meiotic recombination events. Whole ensembles of such numerous haplotypes are subjected to evolutionary pressure, where mutations influence each other and should be considered as a whole entity—a gigantic matrix, unique for each individual genome. This idea was implemented into a computational approach, named Genome Evolution by Matrix Algorithms (GEMA) to model genomic changes taking into account all mutations in a population. GEMA has been tested for modeling of entire human chromosomes. The program can precisely mimic real biological processes that have influence on genome evolution such as: 1) Authentic arrangements of genes and functional genomic elements, 2) frequencies of various types of mutations in different nucleotide contexts, and 3) nonrandom distribution of meiotic recombination events along chromosomes. Computer modeling with GEMA has demonstrated that the number of meiotic recombination events per gamete is among the most crucial factors influencing population fitness. In humans, these recombinations create a gamete genome consisting on an average of 48 pieces of corresponding parental chromosomes. Such highly mosaic gamete structure allows preserving fitness of population under the intense influx of novel mutations (40 per individual) even when the number of mutations with deleterious effects is up to ten times more abundant than those with beneficial effects. PMID:24723728

Qiu, Shuhao; McSweeny, Andrew; Choulet, Samuel; Saha-Mandal, Arnab; Fedorova, Larisa; Fedorov, Alexei

2014-01-01

249

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

PubMed Central

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

Makádi, László; Caldwell, Michael W.; ?si, Attila

2012-01-01

250

Magnetic control of ferroelectric polarization.  

PubMed

The magnetoelectric effect--the induction of magnetization by means of an electric field and induction of polarization by means of a magnetic field--was first presumed to exist by Pierre Curie, and subsequently attracted a great deal of interest in the 1960s and 1970s (refs 2-4). More recently, related studies on magnetic ferroelectrics have signalled a revival of interest in this phenomenon. From a technological point of view, the mutual control of electric and magnetic properties is an attractive possibility, but the number of candidate materials is limited and the effects are typically too small to be useful in applications. Here we report the discovery of ferroelectricity in a perovskite manganite, TbMnO3, where the effect of spin frustration causes sinusoidal antiferromagnetic ordering. The modulated magnetic structure is accompanied by a magnetoelastically induced lattice modulation, and with the emergence of a spontaneous polarization. In the magnetic ferroelectric TbMnO3, we found gigantic magnetoelectric and magnetocapacitance effects, which can be attributed to switching of the electric polarization induced by magnetic fields. Frustrated spin systems therefore provide a new area to search for magnetoelectric media. PMID:14603314

Kimura, T; Goto, T; Shintani, H; Ishizaka, K; Arima, T; Tokura, Y

2003-11-01

251

Galaxy Mass Assembly with VLT & HST and lessons for E-ELT/MOSAIC  

NASA Astrophysics Data System (ADS)

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.

Hammer, François; Flores, Hector; Puech, Mathieu

2015-02-01

252

The Internal Subbetic of the Velez Rubio area (SE Spain): Is it tectonically detached or not?  

NASA Astrophysics Data System (ADS)

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.

Sanz de Galdeano, Carlos; López Garrido, Angel Carlos; Andreo, Bartolomé

2015-01-01

253

Human growth hormone and prolactin secreting pituitary adenomas analyzed by in situ hybridization.  

PubMed Central

Acidophilic pituitary adenomas commonly produce growth hormone (GH) or prolactin (PRL), according to studies employing immunohistochemical and ultrastructural methods. To examine this question, in situ hybridization with oligonucleotide probes was done on routinely processed tissues received in the pathology laboratory to analyze for the presence of GH and PRL messenger RNA (mRNA) in 4 normal pituitaries, 10 prolactinomas, and 16 GH-secreting adenomas. Most acidophilic cells in normal pituitaries expressed either GH or PRL hormone and the respective mRNAs, but GH mRNA and PRL hormone were also detected in some of the same cells. Patients with a clinical diagnosis of prolactinoma had cells with only PRL mRNA in their tumors, while most (14 of 16) patients with a clinical diagnosis of acromegaly or gigantism had both GH and PRL mRNAs in their tumors. The GH adenomas varied in these studies. In situ hybridization was helpful in characterizing the adenoma from a patient with acromegaly who had immunoreactive PRL, but no immunoreactive GH in the resected tumor; in situ hybridization analysis revealed mRNAs for both GH and PRL in the same tumor cells. Our findings indicate that pituitary adenomas from patients with acromegaly commonly express PRL mRNA. It is concluded that in situ hybridization provides new information about the clinical biology and the histopathologic classification of pituitary adenomas. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:2466405

Lloyd, R. V.; Cano, M.; Chandler, W. F.; Barkan, A. L.; Horvath, E.; Kovacs, K.

1989-01-01

254

The Influence of Extremely Large Solar Proton Events in a Changing Stratosphere. Stratospheric Influence of Solar Proton Events  

NASA Technical Reports Server (NTRS)

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.

Jackman, Charles H.; Fleming, Eric L.; Vitt, Francis M.

1999-01-01

255

Galaxies Behind the Milky Way and the Great Attractor  

NASA Astrophysics Data System (ADS)

Dust and stars in the plane of the Milky Way create a "Zone of Avoidance" in the extragalactic sky. Galaxies are distributed in gigantic labyrinth formations, filaments and great walls with occasional dense clusters. They can be traced all over the sky, except where the dust within our own galaxy becomes too thick - leaving about 25% of the extragalactic sky unaccounted for. Our Galaxy is a natural barrier which constrains the studies of large-scale structures in the Universe, the peculiar motion of our Local Group of galaxies and other streaming motions (cosmic flows) which are important for understanding formation processes in the Early Universe and for cosmological models.Only in recent years have astronomers developed the techniques to peer through the disk and uncover the galaxy distribution in the Zone of Avoidance. I present the various observational multi-wavelength procedures (optical, far infrared, near infrared, radio and X-ray) that are currently being pursued to map the galaxy distribution behind our Milky Way, including a discussion of the (different) limitations and selection effects of these (partly) complementary approaches. The newly unveiled large-scale structures are discussed and compared to predictions from theoretical reconstructions of the mass density field. Particular emphasis is given to discoveries in the Great Attractor region - a from streaming motions predicted huge overdensity centered behind the Galactic Plane. The recently unveiled massive rich cluster A3627 seems to constitute the previously unidentified core of the Great Attractor.

Kraan-Korteweg, Renee C.

256

Highly viscous liquid crystalline mixtures: the alternative to liquid crystalline elastomers  

NASA Astrophysics Data System (ADS)

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)

Shibaev, Petr; Schlesier, Cristina; Newman, Leah; McDonald, Scott

2012-02-01

257

Interlayer coupling in ferroelectric bilayer and superlattice heterostructures.  

PubMed

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

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

2006-12-01

258

Chryse Basin channels: low-gradients and ponded flows.  

USGS Publications Warehouse

Gradients on the floors of the Martian outflow channels that are derived from radar-elevation profiles across Lunae Planum and Chryse Basin have much lower values than those obtained from the U.S. Geological Survey's topographic map. Whereas the gradients of Maja and Ares Valles are similar to those of the catastrophic flood channels in the Scablands of Washington State, the gradients of Simud and Tiu Valles are essentially level, and the movement of fluids to the N poses problems. It is proposed that ponding may have formed lakes in depressions associated with the Valles Marineris grabens, ancient craters in the chaotic terrain area, and possibly even the regional low where most chaotic terrains occur. It is envisaged that lakes eventually overflowed, forming the present channels. When dams broke, floods were released catastrophically, with a final gigantic flood from the Valles Marineris system of troughs, which would have had sufficient head to move fluids across nearly level gradients through the Simud and Tiu channels. -P.Br.

Lucchitta, B.K.; Ferguson, H.M.

1983-01-01

259

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

PubMed

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

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

260

Transcending the replacement paradigm of solid-state lighting.  

PubMed

The field of photonics starts with the efficient generation of light. The generation of efficient yet highly controllable light can indeed be accomplished with light-emitting diodes (LEDs), which are, in principle, capable of generating white light with a 20 times greater efficiency than conventional light bulbs. Deployed on a global scale to replace conventional sources, such solid-state light sources will result in enormous benefits that, over a period of 10 years, include (1) gigantic energy savings of 1.9 x 1020 joule, (2) a very substantial reduction in global-warming CO2 emissions, (3) a strong reduction in the emission of pollutants such as acid-rain-causing SO2, mercury (Hg), and uranium (U), and (4) financial savings exceeding a trillion (10(12)) US$. These benefits can be accomplished by the "replacement paradigm" in which conventional light sources are replaced by more energy efficient, more durable, and non-toxic light sources. However, it will be shown that solid-state light sources can go beyond the replacement paradigm, by providing new capabilities including the control of spectrum, color temperature, polarization, temporal modulation, and spatial emission pattern. We will show that such future, "smart" light sources, can harness the huge potential of LEDs by offering multi-dimensional controllability that will enhance the functionality and performance of light sources in a wide range of applications. These applications include optical microscopy, imaging, display technologies, communications, networking, and transportation systems. PMID:19104616

Kim, Jong Kyu; Schubert, E Fred

2008-12-22

261

Earth After the Moon Forming Impact  

NASA Technical Reports Server (NTRS)

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.

Zahnle, Kevin

2006-01-01

262

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

PubMed

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

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

2013-07-22

263

A giant crocodile in the Dubois Collection from the Pleistocene of Kali Gedeh (Java).  

PubMed

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

Delfino, Massimo; De Vos, John

2014-03-01

264

Giant blocks in the South Kona landslide, Hawaii  

USGS Publications Warehouse

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

Moore, J.G.; Bryan, W.B.; Beeson, M.H.; Normark, W.R.

1995-01-01

265

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

PubMed

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

Yuen, Foo Keng

2014-01-01

266

No evidence for directional evolution of body mass in herbivorous theropod dinosaurs  

PubMed Central

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

Zanno, Lindsay E.; Makovicky, Peter J.

2013-01-01

267

An Improved Distance Matrix Computation Algorithm for Multicore Clusters  

PubMed Central

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

Al-Neama, Mohammed W.; Reda, Naglaa M.; Ghaleb, Fayed F. M.

2014-01-01

268

Practical assay for nitrite and nitrosothiol as an alternative to the griess assay or the 2,3-diaminonaphthalene assay.  

PubMed

Nitrite is a heavily assayed substrate in the fields of food safety, water quality control, disease diagnosis, and forensic investigation and more recently in basic biological studies on nitric oxide physiology and pathology. The colorimetric Griess assay and the fluorimetric 2,3-diaminonaphthalene (DAN) assay are the current gold standards for nitrite quantification. They are not without limitations, yet have amazingly survived 156 and 44 years, respectively, due to the lack of a practical alternative. Both assays exhibit slow detection kinetics due to inactivation of nucleophiles under strongly acidic media, require an extensive incubation time for reaction to go completion, and hence offer a limited detection throughput. By converting an intermolecular reaction of the Griess assay intramolecularly, we designed a novel probe (NT555) for nitrite detection, which displays superior detection kinetics and sensitivity. NT555 was constructed following our "covalent-assembly" probe design principle. Upon detection, it affords a gigantic bathochromic shift of the absorption spectrum and a sensitive turn-on fluorescence signal from a zero background, both of which are typical of an "assembly" type probe. Overall, NT555 has addressed various difficulties associated with the Griess and the DAN assays and represents an attractive alternative for practical applications. PMID:25519711

Shen, Yanming; Zhang, Quanjuan; Qian, Xuhong; Yang, Youjun

2015-01-20

269

Semiconductor electronics and the birth of the modern science of surfaces  

NASA Astrophysics Data System (ADS)

Semiconductor surfaces were the launching platform for the solid state electronic revolution. The brilliant concept of surface states led directly to the discovery of the transistor in 1947. The chemical instability of the Ge surfaces, however, rendered the new devices irreproducible and unstable. This threat to the viability of semiconductor electronics, precipitated an international search, of a magnitude unparalleled in the history of science and technology, directed at the understanding and controlling of semiconductor surfaces. The roots of all of today's powerful experimental tools, techniques, procedures and fundamental concepts at the disposal of surface science and engineering can be traced to that gigantic effort on the study of semiconductor surfaces. Clearly, solid state electronics, born and nurtured on semiconductor surfaces, gave, in turn, birth to the modern science of all surfaces. In this article, I attempt to convey a general impression of the mutually constructive interplay between the evolution of solid state electronics on the one hand and surface science and engineering on the other. I take this opportunity to highlight my own experiences and research involvement with semiconductor surfaces.

Gatos, Harry C.

1994-01-01

270

Magnetic disturbance generation during the historic magnetic storm in September 1859  

NASA Astrophysics Data System (ADS)

The model calculation of a magnetic disturbance, which was registered at Colaba observatory (India) during the historic giant magnetic storm on September 1-2, 1859, is illustrated. The calculation demonstrates that the observed, unusually fast, 2-h main phase of this storm, when the negative amplitude of the geomagnetic field vector H component was -1600 nT, and an extremely fast (1.5-h) initial field recovery phase from the maximum to the -110 nT amplitude can be generated. The following models of the magnetospheric current systems were used in the calculations: the ring current ( DR), the magnetospheric magnetopause current ( DCF), the magnetotail current system ( DT), and the high-latitude current system ( DP). The unusual time variation in the registered geomagnetic disturbance is related to the probable fast and considerable equatorward shift of the high-latitude currents during the main phase of the analyzed giant storm and to the same fast backward motion of these currents during the initial field recovery phase. The unusually large amplitude of the registered geomagnetic disturbance could have been caused by the total contribution of the indicated magnetospheric current systems during the time when the storm was generated as a result of the interaction between the magnetosphere and the solar plasma ejected during the gigantic solar flare before the storm.

Levitin, A. E.; Dremukhina, L. A.; Gromova, L. I.; Ptitsyna, N. G.

2014-05-01

271

Long-term monitoring of fish farms: application of Nematode/Copepod index to oligotrophic conditions.  

PubMed

Interannual variability (2003-2008) of meiofaunal assemblages were analyzed in sediments beneath fish cages (Impact group) and in areas not affected by aquaculture activities (Control group). Organisms responded with spatial and seasonal variation in meiofauna assemblages, with an abrupt increase of abundances in locations beneath fish cages throughout the study period. This increase was greater during the last sampling year (2008) and mainly due to high abundances of nematodes. Univariate analyses showed differences between control and impacted sites at both sites, however, only significant variations were found in Los Gigantes, which are consistent with seasonal meiofauna variations throughout the study period. These results are partially explained by differences in current velocity between both sampling areas. The Ne/Co index showed the same trend and it seems to be a reliable index in sediment slightly affected by aquaculture wastes. This index is especially recommended in oligotrophic areas (e.g. Canary Islands) where meiofaunal assemblages are poorly represented in terms of abundances. PMID:22317790

Riera, Rodrigo; Sanchez-Jerez, Pablo; Rodríguez, Myriam; Monterroso, Oscar; Ramos, Eva

2012-04-01

272

Intercontinental dispersal of giant thermophilic ants across the Arctic during early Eocene hyperthermals  

PubMed Central

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

Archibald, S. Bruce; Johnson, Kirk R.; Mathewes, Rolf W.; Greenwood, David R.

2011-01-01

273

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

PubMed Central

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

Lawrence, Peter A.; Casal, José

2013-01-01

274

Using a smart phone application to measure high-energy radiation from thunderstorms  

NASA Astrophysics Data System (ADS)

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.

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

275

Interplay between Superconductivity and Magnetism in Fe1-xPdxTe  

SciTech Connect

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).

Karki, A B [Louisiana State University; Garlea, Vasile O [ORNL; Custelcean, Radu [ORNL; Stadler, S. [Louisiana State University; Plummer, E. W. [Louisiana State University; Jin, Rongying [Louisiana State University

2013-01-01

276

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

PubMed

Giant insects, with wingspans as large as 70 cm, ruled the Carboniferous and Permian skies. Gigantism has been linked to hyperoxic conditions because oxygen concentration is a key physiological control on body size, particularly in groups like flying insects that have high metabolic oxygen demands. Here we show, using a dataset of more than 10,500 fossil insect wing lengths, that size tracked atmospheric oxygen concentrations only for the first 150 Myr of insect evolution. The data are best explained by a model relating maximum size to atmospheric environmental oxygen concentration (pO(2)) until the end of the Jurassic, and then at constant sizes, independent of oxygen fluctuations, during the Cretaceous and, at a smaller size, the Cenozoic. Maximum insect size decreased even as atmospheric pO(2) rose in the Early Cretaceous following the evolution and radiation of early birds, particularly as birds acquired adaptations that allowed more agile flight. A further decrease in maximum size during the Cenozoic may relate to the evolution of bats, the Cretaceous mass extinction, or further specialization of flying birds. The decoupling of insect size and atmospheric pO(2) coincident with the radiation of birds suggests that biotic interactions, such as predation and competition, superseded oxygen as the most important constraint on maximum body size of the largest insects. PMID:22665762

Clapham, Matthew E; Karr, Jered A

2012-07-01

277

Mutation Update: The Spectra of Nebulin Variants and Associated Myopathies  

PubMed Central

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

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

278

Structural Control of Giant Rock Avalanches in Argentina  

NSDL National Science Digital Library

Jigsaw version: To prepare, students do background reading on landslides and rock avalanches and read the introductory portion of Hermanns and Strecker's 1999 article on rock avalanches in Argentina. In class, students receive data (assembled from figures in the article) on bedrock geology and physiography, as well as stereonets showing orientations of prominent joint sets, bedding, and foliations in the bedrock. Their task is to answer the question of why gigantic rock avalanches occur is some places but not others in this part of Argentina. Each student receives one of four possible data sets and works with a team to analyze the data and solve the problem for the team's area. Each team member must then individually explain his/her analysis to a group of three other students, one from each of the other teams, and the group then compares the four locations for similarities and differences. The activity gives students practice in interpreting geologic maps, using stereonets, and peer teaching. The activity also connects structural geology to another geoscience discipline.Short case example version: This is an abbreviated version of the jigsaw activity described above and focuses on only one of the rock avalanche areas.

Barb Tewksbury

279

Energy and globalization  

NASA Astrophysics Data System (ADS)

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".

Birjandi, Hossein Saremi

280

Pituitary Tumors in Childhood: an update in their diagnosis, treatment and molecular genetics  

PubMed Central

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

Keil, Margaret F.; Stratakis, Constantine A.

2009-01-01

281

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

NASA Astrophysics Data System (ADS)

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.

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

2006-11-01

282

Ultrafast observation of critical nematic fluctuations and giant magnetoelastic coupling in iron pnictides  

SciTech Connect

Many of the iron pnictides have strongly anisotropic normal-state characteristics, important for the exotic magnetic and superconducting behaviour these materials exhibit. Y et, the origin of the observed anisotropy is unclear. Electronically driven nematicity has been suggested, but distinguishing this as an independent degree of freedom from magnetic and structural orders is dif?cult, as these couple together to break the same tetragonal symmetry. Here we use time-resolved polarimetry to reveal critical nematic ?uctuations in unstrained Ba(Fe1 À xCox)2As2. The femtosecond anisotropic response, which arises from the two-fold in-plane anisotropy of the complex 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 a critical divergence approaching the structural transition temperature. The dynamics also reveal a gigantic magnetoelastic coupling that far exceeds electron–spin and electron–phonon couplings, opposite to conventional magnetic metals.

Patz, Aaron [Ames Laboratory; Li, Tianqi [Ames Laboratory; ran, Sheng [Ames Laboratory; Fernandes, Rafael M. [University of Minnesota; Schmalian, Joerg [Karlsruhe Institute of Technology; Budko, Sergey L. [Ames Laboratory; Canfield, Paul C. [Ames Laboratory; Perakis, Ilias E. [University of Crete; Wang, Jigang [Ames Laboratory

2014-02-06

283

Supermassive Stars: Fact or Fiction?  

E-print Network

Supermassive black holes are now realized to exist in the centers of most galaxies. The recent discoveries of luminous quasars at redshifts higher than 6 require that these black holes were assembled already when the Universe was less than a billion years old. They might originate from the collapse of supermassive stars, a scenario which could ensure a sufficiently rapid formation. Supermassive stars are dominated by photon pressure and radiate at their Eddington limit, which drives their quasi-static evolution to a final relativistic instability. Above some critical value of the metallicity, their collapse can lead to a gigantic explosion, powered by the energy release due to hydrogen burning, but below this critical metallicity their collapse inevitably ends in the formation of a black hole, accompanied by the emission of huge amounts of energy in the form of neutrinos. Although collapsing supermassive stars are the most powerful known burst sources of neutrinos, the associated conditions do not appear favorable for producing highly relativistic outflows that can explain cosmic gamma-ray bursts.

H. -Th. Janka

2002-02-01

284

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)

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 ?Nd(t) varying between +3.6 and +6.4 and zircon ?Hf(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.

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

285

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

PubMed Central

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

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

2013-01-01

286

Catastrophic Hsiaolin landslide in southern Taiwan triggered by Morakot Typhoon: Insights from 3-D discrete element simulation  

NASA Astrophysics Data System (ADS)

The Typhoon Morakot on August 8th 2009 bought a heavy rainfall in southern Taiwan and caused a catastrophic landslide which buried Hsiaolin Village of Kaohsiung County in southern Taiwan and caused a mortality of more than 400 people. The landslide initiated at Shamdushan from a slope of about 500 m to 900 m above the riverbed and huge amount of slide materials moved quickly downward and became a debris flow. A part of debris topped over the highland of 590 m and spread on the hillslope. The slide materials finally destroyed the Hsiaolin village. Most debris kept downward movement along the gully and reached the Chishan River, and blocked the main stream forming a dammed lake. In this study, we used 3D discrete element method with granular particle assemblage (PFC3D) to simulate kinematic process and mechanics of this catastrophic landslide. According to the 3-D numerical simulation, Hsiaolin village might be buried in 60 seconds after the triggering of landslide in Shamdushan. The predicted maximum velocity is about 50 m/sec and the debris could reach to the other side of the Chishan River. Consequently a dammed lake was formed in the Chishan River. From the viewpoint of the assessment of catastrophic landslides, the analysis of sensibility of landslide potential is a crucial topics, furthermore the 3-D discrete element method is a powerful tool to elucidate the mechanics and kinematics of landslide process and impact area induced by gigantic landslide event.

Hu, Jyr-Ching; Tang, Chao-Lung; Lo, Chia-Ming; Lin, Ming-Lang; Dong, Jia-Jyun; Lee, Chyi-Tyi

2010-05-01

287

Numerical simulation of the tsunami generated by a past catastrophic landslide on the volcanic island of Ischia, Italy  

NASA Astrophysics Data System (ADS)

The island of Ischia, Gulf of Naples, Italy, like many other volcanic islands is affected by mass failures, that are mainly related to secondary volcanic processes such as slope steepening and seismic shaking. The block resurgence of its main relief, Mount Epomeo, has been recognised to contribute cyclically to mass instability and cause landslides, that occasionally may reach the sea and start tsunamis. In this work we explore the consequences of the Ischia Debris Avalanche (IDA), a flank collapse that occurred in historical times, and involved the whole Mount Epomeo edifice including its submarine portion, and that may have caused gigantic sea waves affecting all the coasts of Ischia and of the Gulf of Naples. The IDA and the generated tsunami have been taken as the worst-case scenario for the occurrence of a new tsunami in the area. They have been simulated through numerical codes developed and maintained by the University of Bologna. The simulation shows that the IDA-induced tsunami attacks severely all the coasts of the Gulf of Naples with the highest waves obtained for the island of Ischia, the island of Capri and the peninsula of Sorrento. The propagation pattern of the IDA tsunami can be used to get hints on the impact that such an event may have had on early populations habiting Gulf of Naples, but also to get clues on the area that could be most severely hit by a tsunami generated by a smaller-scale landslide that may occur in the same source zone.

Tinti, Stefano; Chiocci, Francesco Latino; Zaniboni, Filippo; Pagnoni, Gianluca; de Alteriis, Giovanni

2011-03-01

288

Wafer-scale metasurface for total power absorption, local field enhancement and single molecule Raman spectroscopy.  

PubMed

The ability to detect molecules at low concentrations is highly desired for applications that range from basic science to healthcare. Considerable interest also exists for ultrathin materials with high optical absorption, e.g. for microbolometers and thermal emitters. Metal nanostructures present opportunities to achieve both purposes. Metal nanoparticles can generate gigantic field enhancements, sufficient for the Raman spectroscopy of single molecules. Thin layers containing metal nanostructures ("metasurfaces") can achieve near-total power absorption at visible and near-infrared wavelengths. Thus far, however, both aims (i.e. single molecule Raman and total power absorption) have only been achieved using metal nanostructures produced by techniques (high resolution lithography or colloidal synthesis) that are complex and/or difficult to implement over large areas. Here, we demonstrate a metasurface that achieves the near-perfect absorption of visible-wavelength light and enables the Raman spectroscopy of single molecules. Our metasurface is fabricated using thin film depositions, and is of unprecedented (wafer-scale) extent. PMID:24091825

Wang, Dongxing; Zhu, Wenqi; Best, Michael D; Camden, Jon P; Crozier, Kenneth B

2013-01-01

289

Northwestern Tharsis Latent Outflow Activity Mars  

NASA Astrophysics Data System (ADS)

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.

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.

2000-08-01

290

Thermal Expansion Anomaly Regulated by Entropy  

NASA Astrophysics Data System (ADS)

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.

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

2014-11-01

291

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

NASA Astrophysics Data System (ADS)

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.

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

2002-09-01

292

Developmental palaeontology in synapsids: the fossil record of ontogeny in mammals and their closest relatives  

PubMed Central

The study of fossilized ontogenies in mammals is mostly restricted to postnatal and late stages of growth, but nevertheless can deliver great insights into life history and evolutionary mechanisms affecting all aspects of development. Fossils provide evidence of developmental plasticity determined by ecological factors, as when allometric relations are modified in species which invaded a new space with a very different selection regime. This is the case of dwarfing and gigantism evolution in islands. Skeletochronological studies are restricted to the examination of growth marks mostly in the cement and dentine of teeth and can provide absolute age estimates. These, together with dental replacement data considered in a phylogenetic context, provide life-history information such as maturation time and longevity. Palaeohistology and dental replacement data document the more or less gradual but also convergent evolution of mammalian growth features during early synapsid evolution. Adult phenotypes of extinct mammals can inform developmental processes by showing a combination of features or levels of integration unrecorded in living species. Some adult features such as vertebral number, easily recorded in fossils, provide indirect information about somitogenesis and hox-gene expression boundaries. Developmental palaeontology is relevant for the discourse of ecological developmental biology, an area of research where features of growth and variation are fundamental and accessible among fossil mammals. PMID:20071389

Sánchez-Villagra, Marcelo R.

2010-01-01

293

Atmospheric oxygen level and the evolution of insect body size  

PubMed Central

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

Harrison, Jon F.; Kaiser, Alexander; VandenBrooks, John M.

2010-01-01

294

Star Formation Histories in the Local Group  

E-print Network

Deep color magnitude diagrams extending to the main sequence provide the most direct measure of the detailed star formation history in a stellar population. With large investments of observing time, HST can obtain such data for populations out to 1 Mpc, but its field of view is extremely small in comparison to the size of Local Group galaxies. This limitation severely constrains our understanding of galaxy formation. For example, the largest galaxy in the Local Group, Andromeda, offers an ideal laboratory for studying the formation of large spiral galaxies, but the galaxy shows substructure on a variety of scales, presumably due to its violent merger history. Within its remaining lifetime, HST can only sample a few sight-lines through this complex galaxy. In contrast, a wide field imager could provide a map of Andromeda's halo, outer disk, and tidal streams, revealing the spatially-dependent star formation history in each structure. The same data would enable many secondary studies, such as the age variation in Andromeda's globular cluster system, gigantic samples of variable stars, and microlensing tracers of the galaxy's dark matter distribution.

Thomas M. Brown

2004-07-09

295

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

PubMed Central

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

Pimiento, Catalina; Clements, Christopher F.

2014-01-01

296

Protection of Cities from Small Rockets, Missiles, Projectiles and Mortar Shells  

E-print Network

The authors suggest a low cost closed AB-Dome, which may protect small cities such as Sederot from rockets, mortar shells, chemical and biological weapons. The offered AB-Dome is also very useful in peacetime because it protects the city from outside weather (violent storms, hail) and creates a fine climate within the Dome. The roughly hemispherical AB-Dome is a gigantic inflated thin transparent film, located at altitude up to 1 - 5 kilometers, which converts the city into a closed-loop air system. The film may be armored with a basalt or steel grille or cloth pocket-retained stones that destroy (by collision or detonation) incoming rockets, shells and other projectiles. Such an AB-Dome would even protect the city in case of a third-party nuclear war involving temporary poisoning of the Earth atmosphere by radioactive dust. The building of the offered dome is easy; the film spreads on the ground, the fan engines turn on and the cover rises to the needed altitude and is supported there by a small internal ove...

Bolonkin, Alexander

2008-01-01

297

Effect of Previous Milling of Precursors on Magnetoelectric Effect in Multiferroic {Bi5Ti3FeO_{15}} Ceramic  

NASA Astrophysics Data System (ADS)

Bi5Ti3FeO_{15} magnetoelectric (ME) ceramics have been synthesized and investigated. The ME effect can be described as an induced electric polarization under an external magnetic field or an induced magnetization under an external electric field. The materials in the ME effect are called ME materials, and they are considered to be a kind of new promising materials for sensors, processors, actuators, and memory systems. Multiferroics, the materials in which both ferromagnetism and ferroelectricity can coexist, are the prospective candidates which can potentially host the gigantic ME effect. Bi5Ti3FeO_{15}, an Aurivillius compound, was synthesized by sintering a mixture of Bi2O3, Fe2O3, and TiO2 oxides. The precursor materials were prepared in a high-energy attritorial mill for (1, 5, and 10) h. The orthorhombic Bi5Ti3FeO_{15} ceramics were obtained by a solid-state reaction process at 1313 K. The ME voltage coefficient (? _ME) was measured using the dynamic lock-in method. The highest ME voltage coefficient (? _ME = 8.28 mV{\\cdot } cm^{-1}{\\cdot } Oe^{-1}) is obtained for the sample milled for 1 h at H_DC = 4 Oe (1 Oe = 79.58 A{\\cdot }m^{-1}).

Dercz, J.; Bartkowska, J.; Dercz, G.; Stoch, P.; ?ukasik, M.

2013-04-01

298

A New Azhdarchid Pterosaur from the Late Cretaceous of the Transylvanian Basin, Romania: Implications for Azhdarchid Diversity and Distribution  

PubMed Central

We describe a new taxon of medium-sized (wing span ca. 3 m) azhdarchid pterosaur from the Upper Cretaceous Transylvanian Basin (Sebe? 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

Vremir, Mátyás; Kellner, Alexander W. A.; Naish, Darren; Dyke, Gareth J.

2013-01-01

299

The Phoebe dust ring as seen as by the Cassini dust detector CDA  

NASA Astrophysics Data System (ADS)

Saturn's outermost moon Phoebe has been suggested to be the source of a gigantic diffuse dust extending from Phoebe's to Iapetus' orbital distance. Ejecta particles produced by hypervelocity impacts of interplanetary meteoroids with Phoebe are proposed to slowly migrate inward and eventually strike Iapetus' surface. Because of the similarities between the dark surfaces of Phoebe and Iapetus,, the putative Phoebe ring would naturally explain the pronounced colour dichotomy of Iapetus. About 20 days before Cassini's entry into its orbit around Saturn in 2004, the spacecraft performed a close Phoebe flyby, which has been optimised for detecting ejecta particles released from the moon's surface. The CDA measurements provide an upper constraint for the rate at which Phoebe can resupply a ring with fresh dust. After the flyby Cassini moved within the ring's symmetry plane. Dust data acquired during this early mission phase provide information about the size distribution and number density of Phoebe ring particles. To this aim we reanalysed the dust data obtained during the second half of 2004. Our analysis suggests that the ring must be populated by grains in excess of 40 micron in radius, if the ring is composed of Phoebe ejecta moving in retrograde orbits.

Kempf, S.; Horanyi, M.; Juhasz, A.; Srama, R.; Moragas-Klostermeyer, G.

2011-12-01

300

Sex-specific effects of a parasite evolving in a female-biased host population  

PubMed Central

Background Males and females differ in many ways and might present different opportunities and challenges to their parasites. In the same way that parasites adapt to the most common host type, they may adapt to the characteristics of the host sex they encounter most often. To explore this hypothesis, we characterized host sex-specific effects of the parasite Pasteuria ramosa, a bacterium evolving in naturally, strongly, female-biased populations of its host Daphnia magna. Results We show that the parasite proliferates more successfully in female hosts than in male hosts, even though males and females are genetically identical. In addition, when exposure occurred when hosts expressed a sexual dimorphism, females were more infected. In both host sexes, the parasite causes a similar reduction in longevity and leads to some level of castration. However, only in females does parasite-induced castration result in the gigantism that increases the carrying capacity for the proliferating parasite. Conclusions We show that mature male and female Daphnia represent different environments and reveal one parasite-induced symptom (host castration), which leads to increased carrying capacity for parasite proliferation in female but not male hosts. We propose that parasite induced host castration is a property of parasites that evolved as an adaptation to specifically exploit female hosts. PMID:23249484

2012-01-01

301

Origin and evolution of marginal basins of the NW Pacific: Diffuse-plate tectonic reconstructions  

E-print Network

Formation of the gigantic linked dextral pull-apart basin system in the NW Pacific is due to NNE- to ENE-ward motion of east Eurasia. This mainly was a response to the Indo-Asia collision which started about 50 Ma ago. The displacement of east Eurasia can be estimated using three aspects: (1) the magnitude of pull-apart of the dextral pull-apart basin system, (2) paleomagnetic data from eastern Eurasia and the region around the Arctic, and (3) the shortening deficits in the Large Tibetan Plateau. All the three aspects indicate that there was a large amount (about 1200 km) of northward motion of the South China block and compatible movements of other blocks in eastern Eurasia during the rifting period of the basin system. Such large motion of the eastern Eurasia region contradicts any traditional rigid plate tectonic reconstruction, but agrees with the more recent concepts of non-rigidity of both continental and oceanic lithosphere over geological times. Based on these estimates, the method developed for resto...

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

2012-01-01

302

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

NASA Astrophysics Data System (ADS)

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.

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

2014-04-01

303

Prediction of volcanic eruptions by pseudoanalytic functions  

NASA Astrophysics Data System (ADS)

The imminent Oshima large volcanic eruption in Oshima Island near metropolitan Tokyo, Japan was successfully predicted by a practical method of modeling and numerical simulation. The event showed the same tendency against earth tides with a possible 2023-June-6-Mid-Europe-Gaigantic earthquake and 2042-August-6-Biscay-Alps-Black-Sea-Trech-Gigantic earthquake. Huge and large earthquakes and volcanic eruptions were triggered by their peculiar effective earth tides. The event scrutinized here fully acted as plate tectonics and a mathematical model, as viscoelastic fluid phenomena. At the first stage of the simulation, an elastic-viscoplastic porous medium replaced the actual geologic structure, and then conventional theories for random signals and noises determined the most possible vent of eruption. At the next stage, the temporal three-dimensional pseudoanalytic function solver gave the dynamical simulation of the event in Oshima Island. An integrated procedure of direct and indirect solvers minimized variety types of inevitable ambiguities in the modeling and numerical simulation. The event was given in minute order and in Japan Standard Time.

Miyazaki, T. H.

2008-05-01

304

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

PubMed Central

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

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

2008-01-01

305

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

NASA Astrophysics Data System (ADS)

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 ?V/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.

Mezentsev, A.; Fullekrug, M.

2012-04-01

306

What big eyes you have: the ecological role of giant pterygotid eurypterids.  

PubMed

Eurypterids are a group of extinct chelicerates that ranged for over 200 Myr from the Ordovician to the Permian. Gigantism is common in the group; about 50% of families include taxa over 0.8 m in length. Among these were the pterygotids (Pterygotidae), which reached lengths of over 2 m and were the largest arthropods that ever lived. They have been interpreted as highly mobile visual predators on the basis of their large size, enlarged, robust chelicerae and forward-facing compound eyes. Here, we test this interpretation by reconstructing the visual capability of Acutiramus cummingsi (Pterygotidae) and comparing it with that of the smaller Eurypterus sp. (Eurypteridae), which lacked enlarged chelicerae, and other arthropods of similar geologic age. In A. cummingsi, there is no area of lenses differentiated to provide increased visual acuity, and the interommatidial angles (IOA) do not fall within the range of high-level modern arthropod predators. Our results show that the visual acuity of A. cummingsi is poor compared with that of co-occurring Eurypterus sp. The ecological role of pterygotids may have been as predators on thin-shelled and soft-bodied prey, perhaps in low-light conditions or at night. PMID:25009243

Anderson, Ross P; McCoy, Victoria E; McNamara, Maria E; Briggs, Derek E G

2014-07-01

307

Light Work: Contemporary Artists Consider the Sun  

NASA Astrophysics Data System (ADS)

Modern day life and timekeepers have profoundly affected the way we conceptualize time and our position in the universe. Over the past year, I have been investigating the apparent movement of the Sun both sculpturally and photographically. In this paper, I discuss my collaborations with Woody Sullivan and highlight several of the sundials, both gigantic and intimate, created by University of Washington students in the class Where is Noon? Regarding Giant Sundials that we co-taught in Spring 2003. I have continued to develop artistic approaches to solar events. Some of these sunworks have not been designed specifically to measure the exact time of day as a classic sundial does, but to stimulate a greater awareness of our subjective and paradoxical relationship to nature and technology. Other, almost domestic, poetic, humorous or intimate ways of interacting with science and technology are being actively explored. I will also provide a background to previous works I have done in relation to the Sun and optics, and briefly mention artists who are using astronomical events as a point of departure.

Cummins, Rebecca

2005-01-01

308

The Chandra XRCF Calibration Experience - A Personal Recollection  

NASA Astrophysics Data System (ADS)

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.

Flanagan, Kathryn

2013-01-01

309

DNA Viruses: The Really Big Ones (Giruses)  

PubMed Central

Viruses with genomes greater than 300 kb and up to 1200 kb are being discovered with increasing frequency. These large viruses (often called giruses) can encode up to 900 proteins and also many tRNAs. Consequently, these viruses have more protein-encoding genes than many bacteria, and the concept of small particle/small genome that once defined viruses is no longer valid. Giruses infect bacteria and animals although most of the recently discovered ones infect protists. Thus, genome gigantism is not restricted to a specific host or phylogenetic clade. To date, most of the giruses are associated with aqueous environments. Many of these large viruses (phycodnaviruses and Mimiviruses) probably have a common evolutionary ancestor with the poxviruses, iridoviruses, asfarviruses, ascoviruses, and a recently discovered Marseillevirus. One issue that is perhaps not appreciated by the microbiology community is that large viruses, even ones classified in the same family, can differ significantly in morphology, lifestyle, and genome structure. This review focuses on some of these differences rather than provides extensive details about individual viruses. PMID:20690825

Van Etten, James L.; Lane, Leslie C.; Dunigan, David D.

2010-01-01

310

The evolutionary physiology of animal flight: paleobiological and present perspectives.  

PubMed

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

Dudley, R

2000-01-01

311

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

NASA Astrophysics Data System (ADS)

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.

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

2012-02-01

312

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

PubMed

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

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

2013-06-01

313

The fatal wound of Hector, according to a drawing by Peter Paul Rubens designed for tapestry weaving.  

PubMed

According to the Iliad(Chapter XXII, Verses 322-329), Hector, while fighting his last duel, was almost entirely protected by bronze armor, with only a small area "where the clavicle marks the boundary between neck and thorax" exposed. It was precisely into this area, "the shorter way to death," that Achilles thrust his lance. This fatal wound, although covering Hector with blood, allowed the victim to pronounce a few words. In designing the Story of Achilles, his fourth and last series of drawings especially designed for tapestry weaving, Rubens depicted Achilles stabbing Hector near the midline of his neck. There is evidence that Rubens was always well acquainted with the literary sources of his pictures. It is also likely that he became familiar with contemporary editions of the Iliad that were enhanced with commentaries. Realizing that the wound depicted in his original drawing should have prevented Hector from speaking, Rubens altered the scene, then showing the lance piercing the cervical vascular bundle. The careful scrutiny for literary accuracy that was typical of Rubens' artistic behavior did not prevent an additional minor imprecision in the final tapestry. Nevertheless, his outstanding expressive power enabled him to give form to a gigantic baroque representation of the death of Hector in masterly fashion. PMID:11220386

Rubino, M; Viale, G L

2001-02-01

314

Choosing Between Yeast and Bacterial Expression Systems: Yield Dependent  

NASA Technical Reports Server (NTRS)

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.

Miller, Rebecca S.; Malone, Christine C.; Moore, Blake P.; Burk, Melissa; Crawford, Lisa; Karr, Laurel J.; Curreri, Peter A. (Technical Monitor)

2002-01-01

315

Landslides in Valles Marineris, Mars  

NASA Technical Reports Server (NTRS)

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.

Lucchitta, B. K.

1979-01-01

316

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

NASA Astrophysics Data System (ADS)

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

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

2014-03-01

317

Northwestern Tharsis Latent Outflow Activity Mars  

NASA Technical Reports Server (NTRS)

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.

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

318

Advanced Materials for Sustainable, Clean Energy Future  

SciTech Connect

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.

Yang, Zhenguo

2009-04-01

319

Interplay between superconductivity and magnetism in Fe1?xPdxTe  

PubMed Central

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

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

2013-01-01

320

Palaeomagnetism of the Vredefort meteorite crater and implications for craters on Mars.  

PubMed

Magnetic surveys of the martian surface have revealed significantly lower magnetic field intensities over the gigantic impact craters Hellas and Argyre than over surrounding regions. The reduced fields are commonly attributed to pressure demagnetization caused by shock waves generated during meteorite impact, in the absence of a significant ambient magnetic field. Lower than average magnetic field intensities are also observed above the Vredefort meteorite crater in South Africa, yet here we show that the rocks in this crater possess much higher magnetic intensities than equivalent lithologies found elsewhere on Earth. We find that palaeomagnetic directions of these strongly magnetized rocks are randomly oriented, with vector directions changing over centimetre length scales. Moreover, the magnetite grains contributing to the magnetic remanence crystallized during impact, which directly relates the randomization and intensification to the impact event. The strong and randomly oriented magnetization vectors effectively cancel out when summed over the whole crater. Seen from high altitudes, as for martian craters, the magnetic field appears much lower than that of neighbouring terranes, implying that magnetic anomalies of meteorite craters cannot be used as evidence for the absence of the planet's internally generated magnetic field at the time of impact. PMID:15889090

Carporzen, Laurent; Gilder, Stuart A; Hart, Rodger J

2005-05-12

321

Noachian Faulting: What Do Faults Tell Us About the Tectonic History of Tharsis?  

NASA Technical Reports Server (NTRS)

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).

Anderson, R. C.; Dohm, J. M.

2001-01-01

322

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

NASA Technical Reports Server (NTRS)

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.

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

2004-01-01

323

A possible origin of gamma rays from the Fermi Bubbles  

NASA Astrophysics Data System (ADS)

One of the most exciting discoveries of recent years is a pair of gigantic gamma-ray emission regions, the so-called Fermi bubbles, above and below the Galactic center. The bubbles, discovered by the Fermi space telescope, extend up to ?50° in Galactic latitude and are ?40° wide in Galactic longitude. The gamma-ray emission is also found to correlate with radio, microwave and X-rays emission. The origin of the bubbles and the associated non-thermal emissions are still not clearly understood. Possible explanations for the non-thermal emission include cosmic-ray injection from the Galactic center by high speed Galactic winds/jets, acceleration by multiple shocks or plasma turbulence present inside the bubbles, and acceleration by strong shock waves associated with the expansion of the bubbles. In this paper, I will discuss the possibility that the gamma-ray emission is produced by the injection of Galactic cosmic-rays mainly protons during their diffusive propagation through the Galaxy. The protons interact with the bubble plasma producing ?°-decay gamma rays, while at the same time, radio and microwave synchrotron emissions are produced by the secondary electrons/positrons resulting from the ?± decays.

Thoudam, Satyendra

2014-11-01

324

Initiating the effective unification of black hole horizon area and entropy quantization with quasi-normal modes  

E-print Network

Black hole (BH) quantization may be the key to unlocking a unifying theory of quantum gravity (QG). Surmounting evidence in the field of BH research continues to support a horizon (surface) area with a discrete and uniformly spaced spectrum, but there is still no general agreement on the level spacing. In this specialized and important BH case study, our objective is to report and examine the pertinent groundbreaking work of the strictly thermal and non-strictly thermal spectrum level spacing of the BH horizon area quantization with included entropy calculations, which aims to tackle this gigantic problem. In particular, this work exemplifies a series of imperative corrections that eventually permits a BH's horizon area spectrum to be generalized from strictly thermal to non-strictly thermal with entropy results, thereby capturing multiple preceding developments by launching an effective unification between them. Moreover, the identified results are significant because quasi-normal modes (QNM) and "effective states" characterize the transitions between the established levels of the non-strictly thermal spectrum.

C. Corda; S. H. Hendi; R. Katebi; N. O. Schmidt

2014-07-09

325

New Indivisible Planetary Science Paradigm  

E-print Network

I present here a new, indivisible planetary science paradigm, a wholly self-consistent vision of the nature of matter in the Solar System, and dynamics and energy sources of planets. Massive-core planets formed by condensing and raining-out from within giant gaseous protoplanets at high pressures and high temperatures. Earth's complete condensation included a 300 Earth-mass gigantic gas/ice shell that compressed the rocky kernel to about 66% of Earth's present diameter. T-Tauri eruptions stripped the gases away from the inner planets and stripped a portion of Mercury's incompletely condensed protoplanet, and transported it to the region between Mars and Jupiter where it fused with in-falling oxidized condensate from the outer regions of the Solar System and formed the parent matter of ordinary chondrite meteorites, the main-Belt asteroids, and veneer for the inner planets, especially Mars. In response to decompression-driven planetary volume increases, cracks form to increase surface area and mountain ranges characterized by folding form to accommodate changes in curvature. The differences between the inner planets are primarily the consequence of different degrees of protoplanetary compression. The internal composition of Mercury is calculated by analogy with the Earth. The rationale is provided for Mars potentially having a greater subsurface water reservoir capacity than before realized.

J. Marvin Herndon

2013-06-17

326

New Indivisible Planetary Science Paradigm  

E-print Network

I present here a new, indivisible planetary science paradigm, a wholly self-consistent vision of the nature of matter in the Solar System, and dynamics and energy sources of planets. Massive-core planets formed by condensing and raining-out from within giant gaseous protoplanets at high pressures and high temperatures. Earth's complete condensation included a 300 Earth-mass gigantic gas/ice shell that compressed the rocky kernel to about 66% of Earth's present diameter. T-Tauri eruptions stripped the gases away from the inner planets and stripped a portion of Mercury's incompletely condensed protoplanet, and transported it to the region between Mars and Jupiter where it fused with in-falling oxidized condensate from the outer regions of the Solar System and formed the parent matter of ordinary chondrite meteorites, the main-Belt asteroids, and veneer for the inner planets, especially Mars. In response to decompression-driven planetary volume increases, cracks form to increase surface area and mountain ranges ...

Herndon, J Marvin

2013-01-01

327

A Phororhacoid bird from the Eocene of Africa  

NASA Astrophysics Data System (ADS)

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.

Mourer-Chauviré, Cécile; Tabuce, Rodolphe; Mahboubi, M'hammed; Adaci, Mohammed; Bensalah, Mustapha

2011-10-01

328

A possible origin of gamma rays from the Fermi Bubbles  

E-print Network

One of the most exciting discoveries of recent years is a pair of gigantic gamma-ray emission regions, the so-called Fermi bubbles, above and below the Galactic center. The bubbles, discovered by the Fermi space telescope, extend up to $\\sim 50^\\circ$ in Galactic latitude and are $\\sim 40^\\circ$ wide in Galactic longitude. The gamma-ray emission is also found to correlate with radio, microwave and X-rays emission. The origin of the bubbles and the associated non-thermal emissions are still not clearly understood. Possible explanations for the non-thermal emission include cosmic-ray injection from the Galactic center by high speed Galactic winds/jets, acceleration by multiple shocks or plasma turbulence present inside the bubbles, and acceleration by strong shock waves associated with the expansion of the bubbles. In this paper, I will discuss the possibility that the gamma-ray emission is produced by the injection of Galactic cosmic-rays mainly protons during their diffusive propagation through the Galaxy. Th...

Thoudam, Satyendra

2014-01-01

329

HUBBLE VIEWS A STARRY RING WORLD BORN IN A HEAD-ON COLLISION  

NASA Technical Reports Server (NTRS)

[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

2002-01-01

330

Shedding Light on the Cosmic Skeleton  

NASA Astrophysics Data System (ADS)

Astronomers have tracked down a gigantic, previously unknown assembly of galaxies located almost seven billion light-years away from us. The discovery, made possible by combining two of the most powerful ground-based telescopes in the world, is the first observation of such a prominent galaxy structure in the distant Universe, providing further insight into the cosmic web and how it formed. "Matter is not distributed uniformly in the Universe," says Masayuki Tanaka from ESO, who led the new study. "In our cosmic vicinity, stars form in galaxies and galaxies usually form groups and clusters of galaxies. The most widely accepted cosmological theories predict that matter also clumps on a larger scale in the so-called 'cosmic web', in which galaxies, embedded in filaments stretching between voids, create a gigantic wispy structure." These filaments are millions of light years long and constitute the skeleton of the Universe: galaxies gather around them, and immense galaxy clusters form at their intersections, lurking like giant spiders waiting for more matter to digest. Scientists are struggling to determine how they swirl into existence. Although massive filamentary structures have been often observed at relatively small distances from us, solid proof of their existence in the more distant Universe has been lacking until now. The team led by Tanaka discovered a large structure around a distant cluster of galaxies in images they obtained earlier. They have now used two major ground-based telescopes to study this structure in greater detail, measuring the distances from Earth of over 150 galaxies, and, hence, obtaining a three-dimensional view of the structure. The spectroscopic observations were performed using the VIMOS instrument on ESO's Very Large Telescope and FOCAS on the Subaru Telescope, operated by the National Astronomical Observatory of Japan. Thanks to these and other observations, the astronomers were able to make a real demographic study of this structure, and have identified several groups of galaxies surrounding the main galaxy cluster. They could distinguish tens of such clumps, each typically ten times as massive as our own Milky Way galaxy - and some as much as a thousand times more massive - while they estimate that the mass of the cluster amounts to at least ten thousand times the mass of the Milky Way. Some of the clumps are feeling the fatal gravitational pull of the cluster, and will eventually fall into it. "This is the first time that we have observed such a rich and prominent structure in the distant Universe," says Tanaka. "We can now move from demography to sociology and study how the properties of galaxies depend on their environment, at a time when the Universe was only two thirds of its present age." The filament is located about 6.7 billion light-years away from us and extends over at least 60 million light-years. The newly uncovered structure does probably extend further, beyond the field probed by the team, and hence future observations have already been planned to obtain a definite measure of its size. More information This research was presented in a paper published as a letter in the Astronomy & Astrophysics Journal: The spectroscopically confirmed huge cosmic structure at z = 0.55, by Tanaka et al. The team is composed of Masayuki Tanaka (ESO), Alexis Finoguenov (Max-Planck-Institute for Extraterrestrial Physics, Garching, Germany and University of Maryland, Baltimore, USA), Tadayuki Kodama (National Astronomical Observatory of Japan, Tokyo, Japan), Yusei Koyama (Department of Astronomy, University of Tokyo, Japan), Ben Maughan (H.H. Wills Physics Laboratory, University of Bristol, UK) and Fumiaki Nakata (Subaru Telescope, National Astronomical Observatory of Japan). ESO, the European Southern Observatory, is the foremost intergovernmental astronomy organisation in Europe and the world's most productive astronomical observatory. It is supported by 14 countries: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Italy, the

2009-11-01

331

The 1963 Vajont landslide (Italy) simulated through a numerical 2D code  

NASA Astrophysics Data System (ADS)

On October 9th, 1963, a huge mass of about 260 million m3 collapsed along Mt. Toc flank into the artificial lake called Vajont and generated a gigantic wave that invested the town of Longarone (North-East Italy, about 100 km north of Venice), provoking about 2000 casualties. The event started a public debate on the responsibilities for the disaster, and also raised crucial issues for the scientific and engineering community, regarding reservoir flank instability and safety of the hydroelectric plant. The peculiar features of the event were immediately evident. The clay layers remained uncovered in the upper part of the detachment niche, supporting the hypothesis of a well-defined pre-existing sliding surface, that could explain the high falling velocity (around 20 m/s as a maximum) and the compactness of the deposit layers that were found to sit almost unperturbed on the bottom of the valley. The numerical study presented here contributes to the understanding of dynamics of the Vajont landslide. It is found that the accurate knowledge of the pre- and post-slide morphology provides tight constraints on the parameters of the numerical model, that are tuned to fit the observed deposit. Numerical simulations are carried out by means of the in-house built code UBO-BLOCK2. The initial sliding body is divided into a mesh of interacting volume-conserving blocks, whose motion is computed numerically. The friction coefficient at the base of the landslide is determined through a best fit search by maximizing the degree of overlapping between the calculated and observed deposits. Our best solution is also able to account for the observed slight easterly rotation of the mass, the different behaviors of the eastern and western part of the sliding surface and the retrogressive motion of the slide that after climbing up the opposite flank of the valley reverted velocity to settle down on the bottom of the valley.

Zaniboni, Filippo; Ausilia Paparo, Maria; Elsen, Katharina; Tinti, Stefano

2013-04-01

332

The evolution of high energy accelerators  

SciTech Connect

Accelerators have been devised and built for two reasons: In the first place, by physicists who needed high energy particles in order to have a means to explore the interactions between particles that probe the fundamental elementary forces of nature. And conversely, sometimes accelerator builders produce new machines for higher energy than ever before just because it can be done, and then challenge potential users to make new discoveries with the new means at hand. These two approaches or motivations have gone hand in hand. This lecture traces how high energy particle accelerators have grown from tools used for esoteric small-scale experiments to the gigantic projects of today. So far all the really high-energy machines built and planned in the world--except the SLC--have been ring accelerators and storage rings using the strong-focusing method. But this method has not removed the energy limit, it has only pushed it higher. It would seem unlikely that one can go beyond the Large Hadron Collider (LHC)--but in fact a workshop was held in Sicily in November 1991, concerned with the question of extrapolating to 100 TeV. Other acceleration and beam-forming methods are now being discussed--collective fields, laser acceleration, wake-field accelerators etc., all aimed primarily at making linear colliders possible and more attractive than with present radiofrequency methods. So far it is not entirely clear which of these schemes will dominate particle physics in the future--maybe something that has not been thought of as yet.

Courant, E.D.

1994-08-01

333

Creative strategies of businesses with the holistic eigensolution in manufacturing industries  

NASA Astrophysics Data System (ADS)

It is a mission of this contribution to recognize and synthesize all the efforts in industry and in management science to strengthen our techniques and tools for successfully solving increasingly complex leadership problems in manufacturing industries. With the high standard of the work sharing method--the so called Taylorism principle--for cost efficient and mass production, invented at the beginning of the 20th century and the opening of the world market for global sales of goods and services a gigantic progress in living standards was reached. But at the beginning of the 21st century we are needing new ideas and methods for the guidance of overcoming increasing complexity. The holistic eigensolution presents a new operational framework for viewing and controlling the behavior of businesses. In contrast to the traditional process for viewing complex business systems through the intricate analysis of every part of that system, the authors have employed a technique used by physicists to understand the characteristic of `eigen' behaviors of complex physical systems. This method of systems analysis is achieved by observing interactions between the parts in a whole. This kind of analysis has a rigorous mathematical foundation in the physical world and it can be employed to understand most natural phenomena. Within a holistic framework, the observer is challenged to view the system form just the right perspective so that characteristic eigenmodes reveal themselves. The conclusion of the article describes why exactly the intelligent manufacturing science--especially in a broader sense--has the responsibility and chance to develop the holistic eigensolution framework as a Taylorism II-principle for the 21st century.

Zeichen, Gerfried; Huray, Paul G.

1998-10-01

334

Gigas Meets Ulysses  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site]

Released 9 July 2003

Roughly halfway between the great volcanoes of Olympus Mons and Pavonis Mons, the graben (troughs) of Ulysses Fossae intersect with the furrows of Gigas (gigantic) Sulci. A clear time sequence is evident: first came the formation of the sulci terrain (to the left), which then was fractured by graben radial to Olympus Mons, followed by flooding of lava. All but the deepest graben are filled by lava in the topographic low between the two volcanic rises.

Image information: VIS instrument. Latitude 11.8, Longitude 234.3 East (125.7 West). 19 meter/pixel resolution.

Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

2003-01-01

335

The evolving science of detection of ‘blood doping’  

PubMed Central

Blood doping practices in sports have been around for at least half a century and will likely remain for several years to come. The main reason for the various forms of blood doping to be common is that they are easy to perform, and the effects on exercise performance are gigantic. Yet another reason for blood doping to be a popular illicit practice is that detection is difficult. For autologous blood transfusions, for example, no direct test exists, and the direct testing of misuse with recombinant human erythropoietin (rhEpo) has proven very difficult despite a test exists. Future blood doping practice will likely include the stabilization of the transcription factor hypoxia-inducible factor which leads to an increased endogenous erythropoietin synthesis. It seems unrealistic to develop specific test against such drugs (and the copies hereof originating from illegal laboratories). In an attempt to detect and limit blood doping, the World Anti-Doping Agency (WADA) has launched the Athlete Biological Passport where indirect markers for all types of blood doping are evaluated on an individual level. The approach seemed promising, but a recent publication demonstrates the system to be incapable of detecting even a single subject as ‘suspicious’ while treated with rhEpo for 10–12 weeks. Sad to say, the hope that the 2012 London Olympics should be cleaner in regard to blood doping seems faint. We propose that WADA strengthens the quality and capacities of the National Anti-Doping Agencies and that they work more efficiently with the international sports federations in an attempt to limit blood doping. PMID:22225538

Lundby, Carsten; Robach, Paul; Saltin, Bengt

2012-01-01

336

The giant bite of a new raptorial sperm whale from the Miocene epoch of Peru.  

PubMed

The modern giant sperm whale Physeter macrocephalus, one of the largest known predators, preys upon cephalopods at great depths. Lacking a functional upper dentition, it relies on suction for catching its prey; in contrast, several smaller Miocene sperm whales (Physeteroidea) have been interpreted as raptorial (versus suction) feeders, analogous to the modern killer whale Orcinus orca. Whereas very large physeteroid teeth have been discovered in various Miocene localities, associated diagnostic cranial remains have not been found so far. Here we report the discovery of a new giant sperm whale from the Middle Miocene of Peru (approximately 12-13 million years ago), Leviathan melvillei, described on the basis of a skull with teeth and mandible. With a 3-m-long head, very large upper and lower teeth (maximum diameter and length of 12 cm and greater than 36 cm, respectively), robust jaws and a temporal fossa considerably larger than in Physeter, this stem physeteroid represents one of the largest raptorial predators and, to our knowledge, the biggest tetrapod bite ever found. The appearance of gigantic raptorial sperm whales in the fossil record coincides with a phase of diversification and size-range increase of the baleen-bearing mysticetes in the Miocene. We propose that Leviathan fed mostly on high-energy content medium-size baleen whales. As a top predator, together with the contemporaneous giant shark Carcharocles megalodon, it probably had a profound impact on the structuring of Miocene marine communities. The development of a vast supracranial basin in Leviathan, extending on the rostrum as in Physeter, might indicate the presence of an enlarged spermaceti organ in the former that is not associated with deep diving or obligatory suction feeding. PMID:20596020

Lambert, Olivier; Bianucci, Giovanni; Post, Klaas; de Muizon, Christian; Salas-Gismondi, Rodolfo; Urbina, Mario; Reumer, Jelle

2010-07-01

337

Familial Isolated Pituitary Adenomas (FIPA) and the Pituitary Adenoma Predisposition due to Mutations in the Aryl Hydrocarbon Receptor Interacting Protein (AIP) Gene  

PubMed Central

Pituitary adenomas are one of the most frequent intracranial tumors and occur with a prevalence of approximately 1:1000 in the developed world. Pituitary adenomas have a serious disease burden, and their management involves neurosurgery, biological therapies, and radiotherapy. Early diagnosis of pituitary tumors while they are smaller may help increase cure rates. Few genetic predictors of pituitary adenoma development exist. Recent years have seen two separate, complimentary advances in inherited pituitary tumor research. The clinical condition of familial isolated pituitary adenomas (FIPA) has been described, which encompasses the familial occurrence of isolated pituitary adenomas outside of the setting of syndromic conditions like multiple endocrine neoplasia type 1 and Carney complex. FIPA families comprise approximately 2% of pituitary adenomas and represent a clinical entity with homogeneous or heterogeneous pituitary adenoma types occurring within the same kindred. The aryl hydrocarbon receptor interacting protein (AIP) gene has been identified as causing a pituitary adenoma predisposition of variable penetrance that accounts for 20% of FIPA families. Germline AIP mutations have been shown to associate with the occurrence of large pituitary adenomas that occur at a young age, predominantly in children/adolescents and young adults. AIP mutations are usually associated with somatotropinomas, but prolactinomas, nonfunctioning pituitary adenomas, Cushing disease, and other infrequent clinical adenoma types can also occur. Gigantism is a particular feature of AIP mutations and occurs in more than one third of affected somatotropinoma patients. Study of pituitary adenoma patients with AIP mutations has demonstrated that these cases raise clinical challenges to successful treatment. Extensive research on the biology of AIP and new advances in mouse Aip knockout models demonstrate multiple pathways by which AIP may contribute to tumorigenesis. This review assesses the current clinical and therapeutic characteristics of more than 200 FIPA families and addresses research findings among AIP mutation-bearing patients in different populations with pituitary adenomas. PMID:23371967

Aaltonen, Lauri A.; Daly, Adrian F.

2013-01-01

338

Familial acromegaly due to aryl hydrocarbon receptor-interacting protein (AIP) gene mutation in a Turkish cohort.  

PubMed

Aryl hydrocarbon receptor-interacting protein (AIP) is associated with 15-20% of familial isolated pituitary adenomas and 50-80% of cases with AIP mutation exhibit a somatotropinoma. Herein we report clinical characteristics of a large family where AIP R304X variants have been identified. AIP mutation analysis was performed on a large (n = 52) Turkish family across six generations. Sella MRIs of 30 family members were obtained. Basal pituitary hormone levels were evaluated in 13 family members harboring an AIP mutation. Thirteen of 52 family members (25%) were found to have a heterozygous nonsense germline R304X mutation in the AIP gene. Seven of the 13 mutation carriers (53.8%) had current or previous history of pituitary adenoma. Of these 7 mutation carriers, all but one had somatotropinoma/somatolactotropinoma (85.7% of the pituitary adenomas). Of the 6 acromegaly patients with AIP mutation (F/M: 3/3) the mean age at diagnosis of acromegaly was 32 ± 10.3 years while the mean age of symptom onset was 24.8 ± 9.9 years. Three of the six (50%) acromegaly cases with AIP mutation within the family presented with a macroadenoma and none presented with gigantism. Biochemical disease control was achieved in 66.6% (4/6) of the mutation carriers with acromegaly after a mean follow-up period of 18.6 ± 17.6 years. Common phenotypic characteristics of familial pituitary adenoma or somatotropinoma due to AIP mutation vary between families or even between individuals within a family. PMID:23743763

Niyazoglu, Mutlu; Sayitoglu, Muge; Firtina, Sinem; Hatipoglu, Esra; Gazioglu, Nurperi; Kadioglu, Pinar

2014-06-01

339

Multiple episodes of fluid flow in the SW Barents Sea (Loppa High) evidenced by gas flares, pockmarks and gas hydrate accumulation  

NASA Astrophysics Data System (ADS)

Gas and gas hydrates have gained considerable attention in the last 20 yr due to their possible impact on global climate change from methane escalations. Our study area, the SW Barents Sea, is unique in its evolution due to the effect of glaciations which removed thick layers of sediment from the seabed. Unloading due to erosion and deglaciation resulted in opening of pre-existing faults and creation of new ones, facilitating fluid migration and eventually escape into the water from the subsurface. Expressions of hydrocarbon gas accumulation and fluid flow such as gas hydrates and pockmarks are widely distributed in the Barents Sea. Several gas flares, some of them 200 m high in echograms, occur along a segment of the Ringvassøy Loppa Fault Complex, indicating open fractures and active fluid flow. Observation of gas flares along regional fault complexes outside pockmark regions indicates that present gas escape occurs along faults only. The pockmark formation and gas flares belong to different episodes of fluid flow. The pockmarks are absent outside soft sediment depocentres indicating that their existence is related to the presence of recording medium. The thin sediment cover in pockmarks and their penetration down into glaciomarine sediments indicate that they formed after deposition of these sediments and that fluid escape was active to the very recent past. Methane hydrate stability zone (MHSZ) modelling shows that after the last glacial maximum 18 000-20 000 14C years ago, the MHSZ has thinned from 600 m to zero in most parts of the SW Barents Sea. The fluid expulsion probably happened after retreat of the glaciers causing release of methane from dissociation of methane hydrates through fluid escape processes which lasted until recently. Bottom simulating reflectors (BSR) observed are probably due to structure II hydrates formed from gas containing higher order hydrocarbon components such as ethane, propane, etc. along with methane. The study area falls close to the new gigantic oil discoveries, Skrugard and Havis, and north of the Snøhvit hydrocarbon field.

Chand, S.; Thorsnes, T.; Rise, L.; Brunstad, H.; Stoddart, D.; Bøe, R.; Lågstad, P.; Svolsbru, T.

2012-05-01

340

Full-kinetic elve model simulations and their comparison with the ISUAL observed events  

NASA Astrophysics Data System (ADS)

The duration of the optical emissions from elves is relatively short (<1 ms), and the intensity of the elve emissions is relatively weaker than that in the other types of TLEs (halos, sprites, blue jets and gigantic jets). Besides the major emission bands (N2-1P, N2-2P, and N2 LBH) [Mende et al., 2005; Kuo et al., 2007; Chang et al., 2010], other minor emissions in elves (e.g., N2+ 1N, O2 Atmoshperic band, O2+ 1N, OI 630 nm, OI 557.7 nm, NO-gamma band and OH* emission band [Huang et al., 2010]) have been explored using the ISUAL Imager equipped with specified filters (630/557.7/427.8-nm for example). We have also developed an electromagnetic finite difference time domain model for elves [Kuo et al., 2007] to investigate the full kinetic chemistry in elves [Sentman et al., 2008; Kuo et al., 2011]. The modeling results can provide the relatively intensity ratios of the major and the minor emissions in elves. The estimated relative intensities can be used to analyze for the involved radiative states and to infer their percentage that fall within the ISUAL Imager filter passing band. The simulation results could also be useful in designing the imager filters for the future TLE survey missions. [*Works were supported in part by the National Space Organization (NSPO) and the National Science Council (NSC) in Taiwan under grants NSC 99-2112-M-006-006-MY3, NSC 99-2111-M-006-001-MY3, NSC 100-2119-M-006-015

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

2011-12-01

341

Earth after the Moon-forming Impact  

NASA Technical Reports Server (NTRS)

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.

Zahnle, K. J.

2006-01-01

342

Testing for intraspecific postzygotic isolation between cryptic lineages of Pseudacris crucifer  

PubMed Central

Phenotypically cryptic lineages appear common in nature, yet little is known about the mechanisms that initiate and/or maintain barriers to gene flow, or how secondary contact between them might influence evolutionary trajectories. The consequences of such contact between diverging lineages depend on hybrid fitness, highlighting the potential for postzygotic isolating barriers to play a role in the origins of biological species. Previous research shows that two cryptic, deeply diverged intraspecific mitochondrial lineages of a North American chorus frog, the spring peeper (Pseudacris crucifer), meet in secondary contact in Southwestern Ontario, Canada. Our study quantified hatching success, tadpole survival, size at metamorphosis, and development time for experimentally generated pure lineage and hybrid tadpoles. Results suggest that lineages differ in tadpole survival and that F1 hybrids may have equal fitness and higher than average mass at metamorphosis compared with pure parental crosses. These findings imply hybrid early life viability may not be the pivotal reproductive isolation barrier helping to maintain lineage boundaries. However, we observed instances of tadpole gigantism, failure to metamorphose, and bent tails in some tadpoles from hybrid families. We also speculate and provide some evidence that apparent advantages or similarities of hybrids compared with pure lineage tadpoles may disappear when tadpoles are raised with competitors of different genetic makeup. This pilot study implies that ecological context and consideration of extrinsic factors may be a key to revealing mechanisms causing negative hybrid fitness during early life stages, a provocative avenue for future investigations on barriers to gene flow among these intraspecific lineages. PMID:24363891

Stewart, Kathryn A; Lougheed, Stephen C

2013-01-01

343

Hellbender Genome Sequences Shed Light on Genomic Expansion at the Base of Crown Salamanders  

PubMed Central

Among animals, genome sizes range from 20 Mb to 130 Gb, with 380-fold variation across vertebrates. Most of the largest vertebrate genomes are found in salamanders, an amphibian clade of 660 species. Thus, salamanders are an important system for studying causes and consequences of genomic gigantism. Previously, we showed that plethodontid salamander genomes accumulate higher levels of long terminal repeat (LTR) retrotransposons than do other vertebrates, although the evolutionary origins of such sequences remained unexplored. We also showed that some salamanders in the family Plethodontidae have relatively slow rates of DNA loss through small insertions and deletions. Here, we present new data from Cryptobranchus alleganiensis, the hellbender. Cryptobranchus and Plethodontidae span the basal phylogenetic split within salamanders; thus, analyses incorporating these taxa can shed light on the genome of the ancestral crown salamander lineage, which underwent expansion. We show that high levels of LTR retrotransposons likely characterize all crown salamanders, suggesting that disproportionate expansion of this transposable element (TE) class contributed to genomic expansion. Phylogenetic and age distribution analyses of salamander LTR retrotransposons indicate that salamanders’ high TE levels reflect persistence and diversification of ancestral TEs rather than horizontal transfer events. Finally, we show that relatively slow DNA loss rates through small indels likely characterize all crown salamanders, suggesting that a decreased DNA loss rate contributed to genomic expansion at the clade’s base. Our identification of shared genomic features across phylogenetically distant salamanders is a first step toward identifying the evolutionary processes underlying accumulation and persistence of high levels of repetitive sequence in salamander genomes. PMID:25115007

Sun, Cheng; Mueller, Rachel Lockridge

2014-01-01

344

Smooth and rapid slip near the Japan Trench during the 2011 Tohoku-oki earthquake revealed by a hybrid back-projection method  

NASA Astrophysics Data System (ADS)

We developed a new back-projection method that uses teleseismic P-waveforms to integrate the direct P-phase with reflected phases from structural discontinuities near the source and used it to estimate the spatiotemporal distribution of the seismic energy release of the 2011 Tohoku-oki earthquake. We projected a normalized cross-correlation of observed waveforms with corresponding Green's functions onto the seismic source region to obtain a high-resolution image of the seismic energy release. Applying this method to teleseismic P-waveform data of the 2011 Tohoku-oki earthquake, we obtained spatiotemporal distributions of seismic energy release for two frequency bands, a low-frequency dataset and a high-frequency dataset. We showed that the energy radiated in the dip direction was strongly frequency dependent. The area of major high-frequency seismic radiation extended only downdip from the hypocenter, whereas the area of major low-frequency seismic radiation propagated both downdip and updip from the hypocenter. We detected a large release of seismic energy near the Japan Trench in the area of maximum slip, which was also the source area of the gigantic tsunami, when we used only the low-frequency dataset. The timing of this large seismic energy release corresponded to an episode of smooth and rapid slip near the Japan Trench, and reflects the strong dependence of the seismic energy distribution obtained on the frequency band of the input waveform dataset. The episode of smooth and rapid slip may have been the trigger for a release of roughly all of the accumulated elastic strain in the seismic source region of the 2011 Tohoku-oki earthquake.

Yagi, Yuji; Nakao, Atsushi; Kasahara, Amato

2012-11-01

345

Analysis of telescope array receivers for deep-space inter-planetary optical communication link between Earth and Mars  

NASA Astrophysics Data System (ADS)

Optical communication technology shows promising prospects to fulfill the large bandwidth communication requirements of future deep-space exploration missions that are launched by NASA and various other international space agencies. At Earth, a telescope with a large aperture diameter is required to capture very weak optical signals that are transmitted from distant planets and to support large bandwidth communication link. A single large telescope has the limitations of cost, single point failure in case of malfunction, difficulty in manufacturing high quality optics, maintenance, and trouble in providing communication operations when transmitting spacecraft is close to the Sun. An array of relatively smaller-sized telescopes electrically connected to form an aggregate aperture area equivalent to a single large telescope is a viable alternative to a monolithic gigantic aperture. In this paper, we present the design concept and analysis of telescope array receivers for an optical communication link between Earth and Mars. Pulse-position modulation (PPM) is used at the transmitter end and photon-counting detectors along with the direct-detection technique are employed at each telescope element in the array. We also present the optimization of various system parameters, such as detector size (i.e., receiver field of view), PPM slot width, and the PPM order M, to mitigate the atmospheric turbulence and background noise effects, and to maximize the communication system performance. The performance of different array architectures is evaluated through analytical techniques and Monte-Carlo simulations for a broad range of operational scenarios, such as, Earth-Mars conjunction, Earth-Mars opposition, and different background and turbulence conditions. It is shown that the performance of the telescope array-based receiver is equivalent to a single large telescope; and as compared to current RF technology, telescope array-based optical receivers can provide several orders of magnitude greater data rates for deep-space communication with Mars.

Hashmi, Ali Javed; Eftekhar, Ali Asghar; Adibi, Ali; Amoozegar, Farid

2010-05-01

346

Evolution of High Tooth Replacement Rates in Sauropod Dinosaurs  

PubMed Central

Background Tooth replacement rate can be calculated in extinct animals by counting incremental lines of deposition in tooth dentin. Calculating this rate in several taxa allows for the study of the evolution of tooth replacement rate. Sauropod dinosaurs, the largest terrestrial animals that ever evolved, exhibited a diversity of tooth sizes and shapes, but little is known about their tooth replacement rates. Methodology/Principal Findings We present tooth replacement rate, formation time, crown volume, total dentition volume, and enamel thickness for two coexisting but distantly related and morphologically disparate sauropod dinosaurs Camarasaurus and Diplodocus. Individual tooth formation time was determined by counting daily incremental lines in dentin. Tooth replacement rate is calculated as the difference between the number of days recorded in successive replacement teeth. Each tooth family in Camarasaurus has a maximum of three replacement teeth, whereas each Diplodocus tooth family has up to five. Tooth formation times are about 1.7 times longer in Camarasaurus than in Diplodocus (315 vs. 185 days). Average tooth replacement rate in Camarasaurus is about one tooth every 62 days versus about one tooth every 35 days in Diplodocus. Despite slower tooth replacement rates in Camarasaurus, the volumetric rate of Camarasaurus tooth replacement is 10 times faster than in Diplodocus because of its substantially greater tooth volumes. A novel method to estimate replacement rate was developed and applied to several other sauropodomorphs that we were not able to thin section. Conclusions/Significance Differences in tooth replacement rate among sauropodomorphs likely reflect disparate feeding strategies and/or food choices, which would have facilitated the coexistence of these gigantic herbivores in one ecosystem. Early neosauropods are characterized by high tooth replacement rates (despite their large tooth size), and derived titanosaurs and diplodocoids independently evolved the highest known tooth replacement rates among archosaurs. PMID:23874921

Smith, Kathlyn M.; Fisher, Daniel C.; Wilson, Jeffrey A.

2013-01-01

347

Identification of old tidal dwarfs near early-type galaxies from deep imaging and H I observations  

NASA Astrophysics Data System (ADS)

It has recently been proposed that the dwarf spheroidal galaxies located in the Local Group discs of satellites (DoSs) may be tidal dwarf galaxies (TDGs) born in a major merger at least 5 Gyr ago. Whether TDGs can live that long is still poorly constrained by observations. As part of deep optical and H I surveys with the Canada-France-Hawaii Telescope (CFHT) MegaCam camera and Westerbork Synthesis Radio Telescope made within the ATLAS3D project, and follow-up spectroscopic observations with the Gemini-North telescope, we have discovered old TDG candidates around several early-type galaxies. At least one of them has an oxygen abundance close to solar, as expected for a tidal origin. This confirmed pre-enriched object is located within the gigantic, but very low surface brightness, tidal tail that emanates from the elliptical galaxy, NGC 5557. An age of 4 Gyr estimated from its SED fitting makes it the oldest securely identified TDG ever found so far. We investigated the structural and gaseous properties of the TDG and of a companion located in the same collisional debris, and thus most likely of tidal origin as well. Despite several Gyr of evolution close to their parent galaxies, they kept a large gas reservoir. Their central surface brightness is low and their effective radius much larger than that of typical dwarf galaxies of the same mass. This possibly provides us with criteria to identify tidal objects which can be more easily checked than the traditional ones requiring deep spectroscopic observations. In view of the above, we discuss the survival time of TDGs and question the tidal origin of the DoSs.

Duc, Pierre-Alain; Paudel, Sanjaya; McDermid, Richard M.; Cuillandre, Jean-Charles; Serra, Paolo; Bournaud, Frédéric; Cappellari, Michele; Emsellem, Eric

2014-05-01

348

New Insights into Non-Avian Dinosaur Reproduction and Their Evolutionary and Ecological Implications: Linking Fossil Evidence to Allometries of Extant Close Relatives  

PubMed Central

It has been hypothesized that a high reproductive output contributes to the unique gigantism in large dinosaur taxa. In order to infer more information on dinosaur reproduction, we established allometries between body mass and different reproductive traits (egg mass, clutch mass, annual clutch mass) for extant phylogenetic brackets (birds, crocodiles and tortoises) of extinct non-avian dinosaurs. Allometries were applied to nine non-avian dinosaur taxa (theropods, hadrosaurs, and sauropodomorphs) for which fossil estimates on relevant traits are currently available. We found that the reproductive traits of most dinosaurs conformed to similar-sized or scaled-up extant reptiles or birds. The reproductive traits of theropods, which are considered more bird-like, were indeed consistent with birds, while the traits of sauropodomorphs conformed better to reptiles. Reproductive traits of hadrosaurs corresponded to both reptiles and birds. Excluding Massospondyluscarinatus, all dinosaurs studied had an intermediary egg to body mass relationship to reptiles and birds. In contrast, dinosaur clutch masses fitted with either the masses predicted from allometries of birds (theropods) or to the masses of reptiles (all other taxa). Theropods studied had probably one clutch per year. For sauropodomorphs and hadrosaurs, more than one clutch per year was predicted. Contrary to current hypotheses, large dinosaurs did not have exceptionally high annual egg numbers (AEN). Independent of the extant model, the estimated dinosaur AEN did not exceed 850 eggs (75,000 kg sauropod) for any of the taxa studied. This estimated maximum is probably an overestimation due to unrealistic assumptions. According to most AEN estimations, the dinosaurs studied laid less than 200 eggs per year. Only some AEN estimates obtained for medium to large sized sauropods were higher (200-400 eggs). Our results provide new (testable) hypotheses, especially for reproductive traits that are insufficiently documented or lacking from the fossil record. This contributes to the understanding of their evolution. PMID:23991160

Werner, Jan; Griebeler, Eva Maria

2013-01-01

349

Targeted Disruption of CDK4 Delays Cell Cycle Entry with Enhanced p27Kip1 Activity  

PubMed Central

The mechanism by which cyclin-dependent kinase 4 (CDK4) regulates cell cycle progression is not entirely clear. Cyclin D/CDK4 appears to initiate phosphorylation of retinoblastoma protein (Rb) leading to inactivation of the S-phase-inhibitory action of Rb. However, cyclin D/CDK4 has been postulated to act in a noncatalytic manner to regulate the cyclin E/CDK2-inhibitory activity of p27Kip1 by sequestration. In this study we investigated the roles of CDK4 in cell cycle regulation by targeted disruption of the mouse CDK4 gene. CDK4?/? mice survived embryogenesis and showed growth retardation and reproductive dysfunction associated with hypoplastic seminiferous tubules in the testis and perturbed corpus luteum formation in the ovary. These phenotypes appear to be opposite to those of p27-deficient mice such as gigantism and gonadal hyperplasia. A majority of CDK4?/? mice developed diabetes mellitus by 6 weeks, associated with degeneration of pancreatic islets. Fibroblasts from CDK4?/? mouse embryos proliferated similarly to wild-type embryonic fibroblasts under conditions that promote continuous growth. However, quiescent CDK4?/? fibroblasts exhibited a substantial (?6-h) delay in S-phase entry after serum stimulation. This cell cycle perturbation by CDK4 disruption was associated with increased binding of p27 to cyclin E/CDK2 and diminished activation of CDK2 accompanied by impaired Rb phosphorylation. Importantly, fibroblasts from CDK4?/? p27?/? embryos displayed partially restored kinetics of the G0-S transition, indicating the significance of the sequestration of p27 by CDK4. These results suggest that at least part of CDK4’s participation in the rate-limiting mechanism for the G0-S transition consists of controlling p27 activity. PMID:10490638

Tsutsui, Tateki; Hesabi, Bahar; Moons, David S.; Pandolfi, Pier Paolo; Hansel, Kimberly S.; Koff, Andrew; Kiyokawa, Hiroaki

1999-01-01

350

Muzzle of South American Pleistocene ground sloths (Xenarthra, Tardigrada).  

PubMed

Sloths are among the most characteristic elements of the Cainozoic of South America and are represented, during the Pleistocene, by approximately nine genera of gigantic ground sloths (Megatheriidae and Mylodontidae). A few contributions have described their masticatory apparatus, but almost no attention has been paid to the reconstruction of the muzzle, an important feature to consider in relation to food intake, and particularly relevant in sloths because of the edentulous nature of the muzzle and its varied morphology. The relationship between dietary habits and shape and width of the muzzle is well documented in living herbivores and has been considered an important feature for the inference of alimentary styles in fossils, providing an interesting methodological tool that deserves to be considered for xenarthrans. The goal of this study was to examine models of food intake by reconstructing the appearance and shape of the muzzle in five species of Pleistocene ground sloths (Megatherium americanum, Glossotherium robustum, Lestodon armatus, Mylodon darwini, and Scelidotherium leptocephalum) using reconstructions of the nasal cartilages and facial muscles involved in food intake. The preservation of the nasal septum, and the scars for muscular attachment in the rostral part of the skulls, allow making a conservative reconstruction of muzzle anatomy in fossil sloths. Wide-muzzled ground sloths (Glossotherium and Lestodon) had a square, nonprehensile upper lip and were mostly bulk-feeders. The lips, coupled with the tongue, were used to pull out grass and herbaceous plants. Narrow-muzzled sloths (Mylodon, Scelidotherium, and Megatherium) had a cone-shaped and prehensile lip and were mixed or selective feeders. The prehensile lip was used to select particular plants or plant parts. PMID:16315216

Bargo, M Susana; Toledo, Néstor; Vizcaíno, Sergio F

2006-02-01

351

West-Antarctic Ice Streams: Analog to Ice Flow in Channels on Mars  

NASA Technical Reports Server (NTRS)

Sounding of the sea floor in front of the Ross Ice Shelf in Antarctica recently revealed large persistent patterns of longitudinal megaflutes and drumlinoid forms, which are interpreted to have formed at the base of ice streams during the list glacial advance. The flutes bear remarkable resemblance to longitudinal grooves and highly elongated streamlined islands found on the floors of some large martian channels, called outflow channels. ln addition, other similarities exist between Antarctic ice streams and outflow channels. Ice streams are 30 to 80 km wide and hundreds of kilometers long, as are the martian channels. Ice stream beds are below sea level. Floors of many martian outflow channels lie below martian datum, which may have been close to or below past martian sea levels. The Antarctic ice stream bed gradient is flat and locally may go uphill, and surface slopes are exceptionally low. So are gradients of martian channels. The depth to the bed in ice streams is 1 to 1.5 km. At bankful stage, the depth of the fluid in outflow channels would have been 1 to 2 km. These similarities suggest that the martian outflow channels, whose origin is commonly attributed to gigantic catastrophic floods, were locally filled by ice that left a conspicuous morphologic imprint. Unlike the West-Antarctic-ice streams, which discharge ice from an ice sheet, ice in the martian channels came from water erupting from the ground. In the cold martian environment, this water, if of moderate volume, would eventually freeze. Thus it may have formed icings on springs, ice dams and jams on constrictions in the channel path, or frozen pools. Given sufficient thickness and downhill surface gradient, these ice masses would have moved; and given the right conditions, they could have moved like Antarctic ice streams.

Lucchitta, B. K.

1997-01-01

352

A New Sauropodomorph Dinosaur from the Early Jurassic of Patagonia and the Origin and Evolution of the Sauropod-type Sacrum  

PubMed Central

Background The origin of sauropod dinosaurs is one of the major landmarks of dinosaur evolution but is still poorly understood. This drastic transformation involved major skeletal modifications, including a shift from the small and gracile condition of primitive sauropodomorphs to the gigantic and quadrupedal condition of sauropods. Recent findings in the Late Triassic–Early Jurassic of Gondwana provide critical evidence to understand the origin and early evolution of sauropods. Methodology/Principal Findings A new sauropodomorph dinosaur, Leonerasaurus taquetrensis gen. et sp. nov., is described from the Las Leoneras Formation of Central Patagonia (Argentina). The new taxon is diagnosed by the presence of anterior unserrated teeth with a low spoon-shaped crown, amphicoelous and acamerate vertebral centra, four sacral vertebrae, and humeral deltopectoral crest low and medially deflected along its distal half. The phylogenetic analysis depicts Leonerasaurus as one of the closest outgroups of Sauropoda, being the sister taxon of a clade of large bodied taxa composed of Melanorosaurus and Sauropoda. Conclusions/Significance The dental and postcranial anatomy of Leonerasaurus supports its close affinities with basal sauropods. Despite the small size and plesiomorphic skeletal anatomy of Leonerasaurus, the four vertebrae that compose its sacrum resemble that of the large-bodied primitive sauropods. This shows that the appearance of the sauropod-type of sacrum predated the marked increase in body size that characterizes the origins of sauropods, rejecting a causal explanation and evolutionary linkage between this sacral configuration and body size. Alternative phylogenetic placements of Leonerasaurus as a basal anchisaurian imply a convergent acquisition of the sauropod-type sacrum in the new small-bodied taxon, also rejecting an evolutionary dependence of sacral configuration and body size in sauropodomorphs. This and other recent discoveries are showing that the characteristic sauropod body plan evolved gradually, with a step-wise pattern of character appearance. PMID:21298087

Pol, Diego; Garrido, Alberto; Cerda, Ignacio A.

2011-01-01

353

The mystical effects of dermatological vehicles.  

PubMed

Topical treatment of the skin is as old as the evolution of man. Instinctively, we try to treat a skin injury or irritation with cooling or soothing substances. Even animals lick their wounds, trusting instinctively in the healing power of saliva. When did this archaic pattern of treatment take the gigantic leap from folk medicine to modern drug therapy? This text illustrates the evolution of topical dermatological vehicles, their application (guidelines) and future use. In particular, a phenomenon that has so far been ignored in product development and clinical testing is the vehicle metamorphosis. In clinical and experimental situations, most dermatological vehicles undergo considerable changes after they have been removed from the primary container and are applied to the skin. Subsequently, the initial structural matrix, and the quantitative composition of the vehicle, will most likely change during and after the mechanical shear associated with application of the product and/or evaporation of ingredients. This natural, but highly dynamic process will generate mini-environments for the active moiety that are difficult to predict and that are crucial to the fate of the active moiety. Despite the reasonable wishes of formulators, clinicians, patients and customers, there are still no universal vehicles. Each drug, at each concentration, requires a different vehicle for optimized therapy. Stability and compatibility of excipients and active moiety are crucial for any commercially available pharmaceutical or cosmetic formulation, together with local and systemic safety of all components. Nonetheless, more diverse and molecularly complex classes of new dermatological vehicles are continuously being researched and refined. The scientific progress has been remarkable when one considers the simple emulsion mixtures that were commonplace in dermatological therapy and still persist to this day in commercial products. It is to be hoped that the result of these research endeavors will be the emergence of more innovative topical formulations, applying engineered bioavailability control systems, with broader applications in topical therapeutic and cosmetic vehicles. PMID:15724099

Surber, Christian; Smith, Eric W

2005-01-01

354

The water balance components of undisturbed tropical woodlands in the Brazilian Cerrado  

NASA Astrophysics Data System (ADS)

Deforestation of the Brazilian Cerrado region has caused major changes in hydrological processes. These changes in water balance components are still poorly understood, but are important for making land management decisions in this region. To understand pre-deforestation conditions, we determined the main components of the water balance for an undisturbed tropical woodland classified as "cerrado sensu stricto denso". We developed an empirical model to estimate actual evapotranspiration (ET) by using flux tower measurements and, vegetation conditions inferred from the enhanced vegetation index and reference evapotranspiration. Canopy interception, throughfall, stemflow, surface runoff, and water table level were assessed from ground measurements. We used data from two Cerrado sites, "Pé de Gigante" - PDG and "Instituto Arruda Botelho" - IAB. Flux tower data from the PDG site collected from 2001 to 2003 was used to develop the empirical model to estimate ET. The other hydrological processes were measured at the field scale between 2011 and 2014 in the IAB site. The empirical model showed significant agreement (R2= 0.73) with observed ET at the daily scale. The average values of estimated ET at the IAB site ranged from 1.91 to 2.60 mm d-1 for the dry and wet season, respectively. Canopy interception ranged from 4 to 20% and stemflow values were approximately 1% of gross precipitation. The average runoff coefficient was less than 1%, while Cerrado deforestation has the potential to increase that amount up to 20 fold. As relatively little excess water runs off (either by surface water or groundwater) the water storage may be estimated by the difference between precipitation and evapotranspiration. Our results provide benchmark values of water balance dynamics in the undisturbed Cerrado that will be useful to evaluate past and future land cover and land use changes for this region.

Oliveira, P. T. S.; Wendland, E.; Nearing, M. A.; Scott, R. L.; Rosolem, R.; da Rocha, H. R.

2014-11-01

355

Nitrogen in Solar System Minor Bodies: Delivery Pathways to Primeval Earth  

NASA Astrophysics Data System (ADS)

Oxygen isotope data point towards enstatite and ordinary chondrites as presumable building blocks of primordial Earth. Nitrogen was incorporated as nitrides to these first building blocks and was outgassed in the early stages of chemical segregation. However, giant impacts with planetesimals played an important role in partially eroding the atmosphere of Earth, and promoting thermal escape of diverse components. As a consequence, the Earth's atmospheric composition could have been subjected to important changes along the eons. A last, and probably less massive, delivery of volatiles took place at the time of a gigantic cataclysm known as Late Heavy Bombardment. During a short interval roughly between 3.9 and 3.8 Gyr ago, a gravitational migration inwards of Jupiter and Saturn occurred, that perturbed hundreds of small bodies rich in water, ammonia, methane and organic compounds that were stored until then in the outer regions. Current atmospheric signatures suggest that by that mechanism a continuous shower of outer-disk primordial components enriched the volatile inventory of terrestrial planets. The relevance of such contribution is still debated, but significant progress has been made in the last decades from the study of undifferentiated bodies. Consequently, planetary scattering of undifferentiated bodies delivered to Earth a significant fraction of minerals, and light elements that could have played a key role in the volatile enrichment the terrestrial crust. I suggest some unexplored pathways to allow a safe delivery of organics to Earth's surface, following recent evidence on meteoroid fragmentation, fireball spectra and Antarctic micrometeorite discoveries. Recent compositional studies of asteroids, comets and meteorites corroborate the need of having more precise data on the abundance and isotopic ratios of N in these minor bodies. Future space missions to primitive bodies like Rosetta, OSIRIS-Rex, Hayabusa II, or Marco Polo-R could help us to complete the big picture, and this chapter tries to compile our present knowledge of its delivery to Earth along the eons.

Trigo-Rodríguez, Josep M.

356

Magnetic Signatures of Impact Fractured Rocks from Sierra Madera, Texas, USA - Implications to Magnetic Anomalies on Mars  

NASA Astrophysics Data System (ADS)

Mars Express Orbiter (sounding radar data) revealed that craters of ancient origin had been covered by thick sediments in northern hemisphere. Mars MOLA topography mission identified many crater on Mars surface. Thus despite the Mars dichotomy, both northern and southern hemisphere have been covered by impacts to similar density. Mars currently has no global magnetic field of internal origin. In southern hemisphere, magnetic field intensities due to anomalies of remanent origin are much lower over the gigantic impact craters (e.g. Hellas, Prometheus, and Argyre). Low magnetic field may not relate to the absence of internal dynamo but due to impacts. For example, the aerial survey over a two billion year old, largest crater on Earth, Vredefort in South Africa observed much lower magnetic intensity over the crater, despite of the strongly magnetized simgle domain (SD) magnetite in shocked granites. Randomized magnetic vector orientations caused by impact may be the origin of the lower magnetic field observed on both Vredefort and Mars. We conducted magnetic analysis for a suite of Sierra Madera Impact deformed rock sites with complete shatter cone structures and multiple striated joint set (MSJS), and the initial results were intriguing. NRM vector orientations, REM ratios, and AF demagnetization curves showed contrasted magnetic signatures between the sites as well as within the samples. The NRM signatures in small scale shatter cones and larger scale shatter cones indicated shock demagnetization (SDM). The peculiar signatures of the site with MSJS may be both SDM and shock magnetization (SRM). We characterized the complexity and distinct magnetic signatures of impact fractured rocks. The results suggest that the size of the shatter cones and structures may reflect the magnetic signatures of both intensity and directions. Also, the dimensional scale of shatter cones is indicative parameters for randomization of the magnetic vector orientations. Such variations may influence on overall magnetic intensity observed from a distance, which relates to magnetic anomalies on Mars and Moons.

Adachi, T.; Kletetschka, G.; Wasilewski, P. J.; Mikula, V.

2007-05-01

357

Rhodolith beds are major CaCO3 bio-factories in the tropical South West Atlantic.  

PubMed

Rhodoliths are nodules of non-geniculate coralline algae that occur in shallow waters (<150 m depth) subjected to episodic disturbance. Rhodolith beds stand with kelp beds, seagrass meadows, and coralline algal reefs as one of the world's four largest macrophyte-dominated benthic communities. Geographic distribution of rhodolith beds is discontinuous, with large concentrations off Japan, Australia and the Gulf of California, as well as in the Mediterranean, North Atlantic, eastern Caribbean and Brazil. Although there are major gaps in terms of seabed habitat mapping, the largest rhodolith beds are purported to occur off Brazil, where these communities are recorded across a wide latitudinal range (2°N-27°S). To quantify their extent, we carried out an inter-reefal seabed habitat survey on the Abrolhos Shelf (16°50'-19°45'S) off eastern Brazil, and confirmed the most expansive and contiguous rhodolith bed in the world, covering about 20,900 km(2). Distribution, extent, composition and structure of this bed were assessed with side scan sonar, remotely operated vehicles, and SCUBA. The mean rate of CaCO(3) production was estimated from in situ growth assays at 1.07 kg m(-2) yr(-1), with a total production rate of 0.025 Gt yr(-1), comparable to those of the world's largest biogenic CaCO(3) deposits. These gigantic rhodolith beds, of areal extent equivalent to the Great Barrier Reef, Australia, are a critical, yet poorly understood component of the tropical South Atlantic Ocean. Based on the relatively high vulnerability of coralline algae to ocean acidification, these beds are likely to experience a profound restructuring in the coming decades. PMID:22536356

Amado-Filho, Gilberto M; Moura, Rodrigo L; Bastos, Alex C; Salgado, Leonardo T; Sumida, Paulo Y; Guth, Arthur Z; Francini-Filho, Ronaldo B; Pereira-Filho, Guilherme H; Abrantes, Douglas P; Brasileiro, Poliana S; Bahia, Ricardo G; Leal, Rachel N; Kaufman, Les; Kleypas, Joanie A; Farina, Marcos; Thompson, Fabiano L

2012-01-01

358

China's battle to save the environment.  

PubMed

By the year 2000 a Great Green Wall of forests may be crossing the country from northwest to northeast, a total of 53 million hectares of green protection from encroaching deserts and erosion, stretching through 12 provinces to increase the nation's forest cover, which now stands at a mere 12.7% of China's territory. Soils have been degraded to a critical level only within the past 150 years. At present, about one-sixth of the total land is affected by erosion. In 1988 more than 11 million hectares of farmland, one-tenth of the total sown acreage, suffered from severe drought. Another 7.5 million hectares of crops were flooded, and grain output has been dropping steadily. China is now importing more than 1 billion tons of food staples to feed its population. In all big cities including the capital Beijing, sulphur dioxide and dust levels in the atmosphere surpass the norm set by the State. The most seriously polluted city in China is Benxi, situated in Liaoning Province, which contains some 420 factories. Shanghai has become a preview of what is in store for many Chinese cities unless urgent anti-pollution measures are designed and implemented. Much of the city's municipal and industrial wastes are simply flushed untreated into rivers and shallow coastal waters. Some 34 billion tons of municipal and industrial wastes are flushed into China's rivers and streams every year. A highly lauded forest farm in Sichuan Province credits afforestation with increased precipitation in the dry season, reduced soil erosion, and a halt to the flooding of some 10 rivers in the region. Many of China's 32,000 species of higher plants are endangered; and similarly, many of the nation's 2200 species of birds and animals, like the giant panda, are threatened with extinction. The country's gigantic population remains the key problem as well as the key to its solution. PMID:12291351

Nash, N

1989-01-01

359

Visions of Our Planet's Atmosphere, Land and Oceans Electronic-Theater 2001  

NASA Technical Reports Server (NTRS)

The NASA/NOAA/AMS Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to Fredericton New Brunswick. Drop in on the Kennedy Space Center and Park City Utah, site of the 2002 Olympics 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 spectacular images from NASA/NOAA and Canadian remote sensing missions like Terra GOES, TRMM, SeaWiFS, Landsat 7, and Radarsat that are visualized & 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 Newsweek, TIME, National Geographic, Popular Science covers & National & International Network TV. New visualization tools allow us to roam & zoom through massive global images eg Landsat tours of the US, Africa, & New Zealand 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 massive dust storms sweeping across Africa. See vortexes and currents in the global oceans that bring up the nutrients to feed tiny plankton and draw the fish, whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. The demonstration is interactively driven by a SGI Onyx II Graphics Supercomputer with four CPUs, 8 Gigabytes of RAM and Terabyte of disk. With multiple projectors on a giant screen. See the city lights, fishing fleets, gas flares and bio-mass burning of the Earth at night observed by the "night-vision" DMSP military satellite.

Hasler, A. F.; Einaudi, Franco (Technical Monitor)

2001-01-01

360

Protection of Cities from Small Rockets, Missiles, Projectiles and Mortar Shells  

E-print Network

The authors suggest a low cost closed AB-Dome, which may protect small cities such as Sederot from rockets, mortar shells, chemical and biological weapons. The offered AB-Dome is also very useful in peacetime because it protects the city from outside weather (violent storms, hail) and creates a fine climate within the Dome. The roughly hemispherical AB-Dome is a gigantic inflated thin transparent film, located at altitude up to 1 - 5 kilometers, which converts the city into a closed-loop air system. The film may be armored with a basalt or steel grille or cloth pocket-retained stones that destroy (by collision or detonation) incoming rockets, shells and other projectiles. Such an AB-Dome would even protect the city in case of a third-party nuclear war involving temporary poisoning of the Earth atmosphere by radioactive dust. The building of the offered dome is easy; the film spreads on the ground, the fan engines turn on and the cover rises to the needed altitude and is supported there by a small internal overpressure. The offered method is cheaper by thousands of times than protection of a city by current anti-rocket systems. The AB-Dome may be also used (height is up to 1-5 and more kilometers) for TV, communication, long distance location, tourism, suspended high speed and altitude windmills (energy), illumination and entertainment (projected messages and pictures). The authors developed the theory of AB-Dome, made estimations, computations and computed a typical project. Discussion and results are at the end of the article.

Alexander Bolonkin; Joseph Friedlander

2008-02-03

361

New insights into regional tectonics of the Indochina Peninsula inferred from Lower-Middle Jurassic paleomagnetic data of the Sibumasu Terrane  

NASA Astrophysics Data System (ADS)

The post-Jurassic occurrence of differential tectonic rotation between the Indochina and South Sundaland blocks remains an issue to be properly investigated. New paleomagnetic study is used here to find the role of Sibumasu Terrane in this rotation, which is located between a clockwise rotated Indochina Block and a counter-clockwise rotated South Sundaland Block. For this purpose, lower to middle Jurassic red sandstones of the Umphang Group in the Sibumasu Terrane were sampled at 21 sites in the Ratchaburi area (13.6°E, 99.6°E), Thailand. Stepwise thermal demagnetization by 680 °C unblocked a pre-folding characteristic remanent magnetization. A mean direction of this component at 100% unfolding is Ds = 348.5°, Is = 24.7°, ?95 = 10.5°, k = 10.7, N = 20, corresponding to an Early-Middle Jurassic pole of ? = 78.6°N, ? = 10.6°E (A95 = 9.3). Comparison of this direction with those reported from other localities of the Umphang Group (Kalaw, Mae Sot and North Trang Syncline localities) reveal variable declinations (between 348.5° and 44.7°) for the Sibumasu Terrane. We ascribe this variation to differential tectonic deformation in the Sibumasu Terrane, as reflected from sinusoidal shaped structural features in the study area. The presence of such features in the granitic rocks indicates the occurrences of deformational activities after their intrusion, which took place in the period between 130 Ma and 51 Ma. The Sibumasu Terrane behaved as an independent fragment at a time when Indochina was undergoing a clockwise rotation and southward displacement, as a result of extrusion tectonics after the gigantic India-Asia collision. Taking into consideration a westerly deflected declination (D = 342.8°) from the West Trang area in Peninsular Thailand, a counterclockwise rotation of 15° is estimated for the Sibumasu Terrane, as a result of continuous northward indentation of the Australian Plate into South Sundaland Block.

Fujiwara, Katsuya P.; Zaman, Haider; Surinkum, Adichat; Chaiwong, Nikhom; Fujihara, Makoto; Ahn, Hyeon-Seon; Otofuji, Yo-ichiro

2014-11-01

362

Thermal and electrical conductivity of iron at Earth's core conditions.  

PubMed

The Earth acts as a gigantic heat engine driven by the decay of radiogenic isotopes and slow cooling, which gives rise to plate tectonics, volcanoes and mountain building. Another key product is the geomagnetic field, generated in the liquid iron core by a dynamo running on heat released by cooling and freezing (as the solid inner core grows), and on chemical convection (due to light elements expelled from the liquid on freezing). The power supplied to the geodynamo, measured by the heat flux across the core-mantle boundary (CMB), places constraints on Earth's evolution. Estimates of CMB heat flux depend on properties of iron mixtures under the extreme pressure and temperature conditions in the core, most critically on the thermal and electrical conductivities. These quantities remain poorly known because of inherent experimental and theoretical difficulties. Here we use density functional theory to compute these conductivities in liquid iron mixtures at core conditions from first principles--unlike previous estimates, which relied on extrapolations. The mixtures of iron, oxygen, sulphur and silicon are taken from earlier work and fit the seismologically determined core density and inner-core boundary density jump. We find both conductivities to be two to three times higher than estimates in current use. The changes are so large that core thermal histories and power requirements need to be reassessed. New estimates indicate that the adiabatic heat flux is 15 to 16 terawatts at the CMB, higher than present estimates of CMB heat flux based on mantle convection; the top of the core must be thermally stratified and any convection in the upper core must be driven by chemical convection against the adverse thermal buoyancy or lateral variations in CMB heat flow. Power for the geodynamo is greatly restricted, and future models of mantle evolution will need to incorporate a high CMB heat flux and explain the recent formation of the inner core. PMID:22495307

Pozzo, Monica; Davies, Chris; Gubbins, David; Alfè, Dario

2012-05-17

363

Dentofacial growth in patients with Sotos syndrome.  

PubMed

Sotos syndrome is an overgrowth syndrome leading to peculiar facial characteristics, large hands and feet, and mental retardation. The maxillofacial characteristics are metopic protrusion, a high and narrow palate and a tapered mandible. In this study, we evaluated changes in maxillofacial growth in 2 patients with cerebral gigantism during the peripubertal period. Patient 1 was a boy aged 8 years at the first examination. The face showed midface retraction and a tapered mandible. Maxillary median diastema with an OJ of 2.5 mm and OB of 1.0 mm was observed, and the molar region showed mandibular mesial occlusion. Radiography revealed a lack of 15, 25, 37, 47, 14, 24, 34 and 44. Cephalometrics demonstrated maxillary and mandibular retrusion with an SNA of 68 degrees and an SNB of 70 degrees , and the patient had leptoprosopia with a mandibular plane of 38.0 degrees . This plane was 45 degrees at the time of re-examination when the patient was 14 years old, showing an increase in the lower facial height and decreases in facial axis and depth. Patient 2 was a boy aged 14 years at the first examination. The face showed mandibular retrusion and tapering. The occlusion was angle class II div. 1, OJ 14 mm, and OB -1 mm. Cephalometrics demonstrated maxillary and mandibular retrusion with an SNA of 74.5 degrees and an SNB of 69.5 degrees , and the patient had leptoprosopia with a mandibular plane of 37.0 degrees . At the time of re-examination, when the patient was 16 years old, the mandibular plane was 42.5 degrees , showing an increase in lower facial height and decreases in facial axis and depth. In this syndrome, excessive facial height without mandibular forward overgrowth is observed. Since the facial height tended to increase by growth during the peripubertal period, maxillofacial vertical growth is considered important in the treatment of this syndrome. PMID:17978548

Takei, Kunio; Sueishi, Kenji; Yamaguchi, Hideharu; Ohtawa, Yumi

2007-05-01

364

Male meiosis, morphometric analysis and distribution pattern of 2× and 4× cytotypes of Ranunculus hirtellus Royle, 1834 (Ranunculaceae) from the cold regions of northwest Himalayas (India)  

PubMed Central

Abstract In this study, we examined the chromosome number, detailed male meiosis, microsporogenesis, pollen fertility and morphological features and distribution of 2× and 4× cytotypes of Ranunculus hirtellus Royle, 1834. The majority of the populations scored now from cold regions of the northwest Himalayas showed tetraploid (n=16) meiotic chromosome count and one of the populations studied from the Manimahesh hills existed at diploid level (n=8). The individuals of diploid cytotype exhibited perfectly normal meiotic course resulting in 100% pollen fertility and pollen grains of uniform sizes. On the other hand, the plants of the tetraploid cytotype from all the populations in spite of showing normal bivalent formation and equal distribution to the opposite poles at anaphases showed various meiotic abnormalities. The most prominent among these meiotic abnormalities was the cytomixis which involved inter PMC (pollen mother cell) chromatin material transfer at different stages of meiosis-I. The phenomenon of cytomixis induced various meiotic abnormalities which include chromatin stickiness, pycnotic chromatin, laggards and chromatin bridges, out of plate bivalents at metaphase-I, disoriented chromatin material at anaphase/telophase and micronuclei. Consequently, these populations exhibited varying percentages of pollen sterility (24 - 77 %) and pollen grains of heterogeneous sizes. Analysis of various morphometric features including the stomata in 2× and 4× cytotypes showed that increase in ploidy level in the species is correlated with gigantism of vegetative and floral characters and the two cytotypes can be distinguished from each other on the basis of morphological characters. The distribution patterns of the 2× and 4× cytotypes now detected and 2×, 3×, 4× cytotypes detected earlier by workers from other regions of the Indian Himalayas have also been discussed. PMID:24260626

Kumar, Puneet; Singhal, Vijay Kumar

2011-01-01

365

Non-characteristic recurrence behavior on the 1942 Niksar-Erbaa earthquake rupture along the North Anatolian fault system, Turkey  

NASA Astrophysics Data System (ADS)

Repeatability of surface slip distribution through earthquake cycles is basis to evaluate size and timing of future large earthquakes generated by active faults. In order to examine characteristic slip hypothesis on the North Anatolian fault system (NAFS), we have systematically performed 3D trenching survey on the 1944 Bolu-Gerede and the 1942 Niksar-Erbaa earthquake ruptures, to simultaneously reconstruct timing and slip associated with paleoearthquakes. These two earthquake segments are relatively well-known on historical earthquake records indicating the timing and the rupture extent. The results suggest that 1) the NAFS is highly segmented in several tens km long, 2) past large earthquakes have been produced by the multi-segment faulting, and 3) each fault segment seems to have their own characteristics of recurrence behavior. At Demir Tepe site on the Gerede segment which recorded the maximum slip during the 1944 earthquake (M7.4), we revealed the repetition of ca. 5-m-slips and quasi-periodic repeat time of ca. 330 year. The reconstructed slip history gives us to support characteristic slip behavior on the segment, although the segment had ruptured during the historical earthquakes with greatly varied rupture length for each. On the other hands, at Ayvaz site on the Niksar segment which recorded 2.5-m-slip during the 1942 earthquake (M7.0), the preliminary results of 3D trenching exhibit 6.0-m-slip during the penultimate event, probably corresponding to the 1668 Anatolian earthquake. Since this gigantic M8 earthquake ruptured through almost half of the entire NAFS, including both the 1944 and the 1942 earthquake segments, the 1942 type earthquake is not characteristic earthquake. This non-characteristic behavior implies various sizes of large earthquakes have occurred on the NAFS. The key for understanding multi-segment ruptures may be recognition of such macroscopic barrier segment like the 1942 earthquake segment.

Kondo, H.; Kürçer, A.; Özalp, S.; Emre, Ö.

2009-04-01

366

Multiple step growth of single crystalline rutile nanorods with the assistance of self-assembled monolayer for dye sensitized solar cells.  

PubMed

A novel multiple step growth (MSG) process has been developed to synthesize rutile nanorods (NRs) on fluorine-doped tin oxide (FTO) glass with the assistance of a self-assembled monolayer (SAM) aiming to increase the internal surface area of the 1D materials for dye sensitized solar cell (DSSC) applications. The experimental result reveals that the SAM layer can be selectively decomposed at the tip of the nanorod, namely the rutile (001) surface, due to the anisotropic photocatalytic property of the rutile. The remaining SAM layer on the side-wall of the NRs remains intact and serves as water repellent which prevents the radial growth of the NRs during the next step hydrothermal synthesis; therefore, the spacing between the NRs and the porosity of the NR array can be retained after additional growth cycles. On the other hand, introduction of a middle layer formed via TiCl4 solution treatment before the next growth cycle is found to be an effective way to control the diameters of the newly grown NRs. The performance of DSSC made from the rutile NRs grown using the MSG technique has been examined, and it is significantly affected by the internal surfaces of the NRs. Furthermore, the MSG combined with NR etching treatment by acid at low temperature (150 °C) leads to a significant enhancement in the solar cell performance. The gigantic wettability difference of the NRs before and after the SAM treatment as well as the MSG method could be adapted to prepare superhydrophobic and superhydrophilic nanostructured patterns for other applications. PMID:24033252

Yang, Mengjin; Neupane, Suman; Wang, Xuewen; He, Jin; Li, Wenzhi; Pala, Nezih

2013-10-01

367

The potential for crustal resources on Mars  

NASA Technical Reports Server (NTRS)

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.

Cordell, Bruce M.; Gillett, Stephen L.

1991-01-01

368

Contributions of Nimbus 7 TOMS Data to Volcanic Study and Hazard Mitigation  

NASA Technical Reports Server (NTRS)

Nimbus TOMS data have led to advancements among many volcano-related scientific disciplines, from the initial ability to quantify SO2 clouds leading to derivations of eruptive S budgets and fluxes, to tracking of individual clouds, assessing global volcanism and atmospheric impacts. Some of the major aspects of TOMS-related research, listed below, will be reviewed and updated: (1) Measurement of volcanic SO2 clouds: Nimbus TOMS observed over 100 individual SO2 clouds during its mission lifetime; large explosive eruptions are now routinely and reliably measured by satellite. (2) Eruption processes: quantification of SO2 emissions have allowed assessments of eruption sulfur budgets, the evaluation of "excess" sulfur, and inferences of H2S emissions. (3) Detection of ash: TOMS data are now used to detect volcanic particulates in the atmosphere, providing complementary analyses to infrared methods of detection. Paired TOMS and AVHRR studies have provided invaluable information on volcanic cloud compositions and processes. (4) Cloud tracking and hazard mitigation: volcanic clouds can be considered gigantic tracers in the atmosphere, and studies of the fates of these clouds have led to new knowledge of their physical and chemical dispersion in the atmosphere for predictive models. (5) Global trends: the long term data set has provided researchers an unparalleled record of explosive volcanism, and forms a key component in assessing annual to decadal trends in global S emissions. (6) Atmospheric impacts: TOMS data have been linked to independent records of atmospheric change, in order to compare cause and effect processes following a massive injection of SO2 into the atmosphere. (7) Future TOMS instruments and applications: Nimbus TOMS has given way to new satellite platforms, with several wavelength and resolution modifications. New efforts to launch a geostationary TOMS could provide unprecedented observations of volcanic activity.

Krueger, Arlin J.; Bluth, G. J. S.; Schaefer, S. A.

1998-01-01

369

Adaptations in the structure and innervation of follicle-sinus complexes to an aquatic environment as seen in the Florida manatee (Trichechus manatus latirostris).  

PubMed

Florida manatees are large-bodied aquatic herbivores that use large tactile vibrissae for several purposes. Facial vibrissae are used to forage in a turbid water environment, and the largest perioral vibrissae can also grasp and manipulate objects. Other vibrissae distributed over the entire postfacial body appear to function as a lateral line system. All manatee vibrissae emanate from densely innervated follicle-sinus complexes (FSCs) like those in other mammals, although proportionately larger commensurate with the caliber of the vibrissae. As revealed by immunofluorescence, all manatee FSCs have many types of C, Adelta and Abeta innervation including Merkel, club, and longitudinal lanceolate endings at the level of the ring sinus, but they lack other types such as reticular and spiny endings at the level of the cavernous sinus. As in non-whisking terrestrial species, the inner conical bodies of facial FSCs are well innervated but lack Abeta-fiber terminals. Importantly, manatee FSCs have two unique types of Abeta-fiber endings. First, all of the FSCs have exceptionally large-caliber axons that branch to terminate as novel, gigantic spindle-like endings located at the upper ring sinus. Second, facial FSCs have smaller caliber Abeta fibers that terminate in the trabeculae of the cavernous sinus as an ending that resembles a Golgi tendon organ. In addition, the largest perioral vibrissae, which are used for grasping, have exceptionally well-developed medullary cores that have a structure and dense small-fiber innervation resembling that of tooth pulp. Other features of the epidermis and upper dermis structure and innervation differ from that seen in terrestrial mammals. PMID:17640045

Sarko, Diana K; Reep, Roger L; Mazurkiewicz, Joseph E; Rice, Frank L

2007-09-20

370

Combining ECS Exploration and Scientific Interest: The Case of the Demarara Plateau Offshore French Guiana (Invited)  

NASA Astrophysics Data System (ADS)

The French national program for the extension of the continental shelf, EXTRAPLAC, started in 2002 with funding from the French Government. It is let by Ifremer, with as principle partners the SHOM (Hydrographic and Oceanographic Service of the Navy), IPEV (French Polar Institute) and IFP Energies Nouvelles. Its aim is to make submissions for extended continental shelf beyond 200 nm to the Commission on the Limits of the Continental Shelf under the UN Convention on the Law of the Sea. Nine submissions, of which 3 are joint with neighboring states, have been made thus far, concerning areas off metropolitan France and its overseas territories. In total, over 360 days of ship time was needed to explore these vast and dispersed areas, in the Atlantic, Pacific and Indian Oceans. The data collected include multibeam bathymetry, seismic reflection and some rock sampling. In this presentation we will describe how the EXTRAPLAC cruise offshore French Guiana (GUYAPLAC, R/V L'Atalante, 2003) let to new scientific results for this transform type margin, in particular in the area of the Demerara Plateau. These include the discovery of gigantic submarine land slides in the subsurface, and associated fluid escape features on the seafloor. A scientific collaboration between the EXTRAPLAC team and academia let to a follow-up cruise proposal to further explore this unique continental margin: The IGUANES cruise, let by the University of Perpignan, took place in April/May 2013, using a higher resolution multibeam echosounder, high resolution seismic reflection and sediment cores. In particular we were able to confirm and better map significant submarine landslide scarps, aligned pockmark fields and sediment waves that likely associated with strong bottom currents and/or the submarine landslides. We will also briefly describe some of the highlight results of other ECS related cruises to show how the EXTRAPLAC program has resulted in new knowledge in remote frontier areas that had very little modern data coverage.

Roest, W. R.; Loncke, L.; Loubrieu, B.

2013-12-01

371

Extreme plasticity in life-history strategy allows a migratory predator (jumbo squid) to cope with a changing climate.  

PubMed

Dosidicus gigas (jumbo or Humboldt squid) is a semelparous, major predator of the eastern Pacific that is ecologically and commercially important. In the Gulf of California, these animals mature at large size (>55 cm mantle length) in 1-1.5 years and have supported a major commercial fishery in the Guaymas Basin during the last 20 years. An El Niño event in 2009-2010, was accompanied by a collapse of this fishery, and squid in the region showed major changes in the distribution and life-history strategy. Large squid abandoned seasonal coastal-shelf habitats in 2010 and instead were found in the Salsipuedes Basin to the north, an area buffered from the effects of El Niño by tidal upwelling and a well-mixed water column. The commercial fishery also relocated to this region. Although large squid were not found in the Guaymas Basin from 2010 to 2012, small squid were abundant and matured at an unusually small mantle-length (<30 cm) and young age (approximately 6 months). Juvenile squid thus appeared to respond to El Niño with an alternative life-history trajectory in which gigantism and high fecundity in normally productive coastal-shelf habitats were traded for accelerated reproduction at small size in an offshore environment. Both small and large mature squid, were present in the Salsipuedes Basin during 2011, indicating that both life- history strategies can coexist. Hydro-acoustic data, reveal that squid biomass in this study area nearly doubled between 2010 and 2011, primarily due to a large increase in small squid that were not susceptible to the fishery. Such a climate-driven switch in size-at-maturity may allow D. gigas to rapidly adapt to and cope with El Niño. This ability is likely to be an important factor in conjunction with longerterm climate-change and the potential ecological impacts of this invasive predator on marine ecosystems. PMID:23505049

Hoving, Henk-Jan T; Gilly, William F; Markaida, Unai; Benoit-Bird, Kelly J; -Brown, Zachary W; Daniel, Patrick; Field, John C; Parassenti, Liz; Liu, Bilin; Campos, Bernardita

2013-07-01

372

Simulação de ejeções de massa coronal  

NASA Astrophysics Data System (ADS)

Ejeções de massa coronal (EMC) são bolhas gigantes de gás permeadas por campos magnéticos que são ejetadas do Sol durante um período de várias horas. Caso estas ejeções atinjam a Terra, geralmente, causam uma série de distúrbios às comunicações de longa distância e navegação, além de danos a satélites e transformadores. Portanto, é desejável que sejamos capazes de prever quando estas ejeções atingirão a Terra. Para tanto, é necessário um bom entendimento dos mecanismos causadores das ejeções e, principalmente, de como se dá a propagação das EMC e sua interação com o vento solar que permeia o meio interplanetário. Nesse sentido foi desenvolvido um programa computacional para resolver as equações MHD (Magneto-Hidro-Dinâmica) que regem a evolução das EMC. Primeiramente foram estabelecidas as condições necessárias para descrever o vento solar, no estado estacionário, que permeia todo o meio interplanetário. Num primeiro momento, resolveu-se o sistema de equações para o caso do vento isotérmico, conhecida como a solução de Parker, a fim de testarmos o modelo. Então, foi considerado o caso do vento solar com temperatura variável no meio interplanetário. Este resultado foi utilizado como a base de nosso sistema em seu instante inicial. Posteriormente foram feitas as considerações necessárias para descrever a propagação da Ejeção de Massa Coronal. As EMC foram simuladas como um aumento de densidade e temperatura local na coroa solar. A órbita e a posição da Terra foram incluídas no sistema. Os dados gerados possibilitaram uma análise da evolução da EMC pelo meio interplanetário até encontrar-se com a Terra. Os perfis de densidade e temperatura a 1 Unidade Astronômica são comparados com os dados de satélites reportados na literatura.

Corsini, M. A.; Silva, A. V. R.

2003-08-01

373

Cosmic Spider is Good Mother  

NASA Astrophysics Data System (ADS)

Hanging above the Large Magellanic Cloud (LMC) - one of our closest galaxies - in what some describe as a frightening sight, the Tarantula nebula is worth looking at in detail. Also designated 30 Doradus or NGC 2070, the nebula owes its name to the arrangement of its brightest patches of nebulosity that somewhat resemble the legs of a spider. This name, of the biggest spiders on Earth, is also very fitting in view of the gigantic proportions of the celestial nebula - it measures nearly 1,000 light years across! ESO PR Photo 11/06 ESO PR Photo 13b/06 Tarantula's Central Cluster, R136 The Tarantula nebula is the largest emission nebula in the sky and also one of the largest known star-forming regions in all the Milky Way's neighbouring galaxies. Located about 170,000 light-years away, in the southern constellation Dorado (The Swordfish), it can be seen with the unaided eye. As shown in this image obtained with the FORS1 multi-mode instrument on ESO's Very Large Telescope, its structure is fascinatingly complex, with a large number of bright arcs and apparently dark areas in between. Inside the giant emission nebula lies a cluster of young, massive and hot stars, denoted R 136, whose intense radiation and strong winds make the nebula glow, shaping it into the form of a giant arachnid. The cluster is about 2 to 3 million years old, that is, almost from 'yesterday' in the 13.7 billion year history of the Universe. Several of the brighter members in the immediate surroundings of the dense cluster are among the most massive stars known, with masses well above 50 times the mass of our Sun. The cluster itself contains more than 200 massive stars. ESO PR Photo 11/06 ESO PR Photo 13c/06 The Stellar Cluster Hodge 301 In the upper right of the image, another cluster of bright, massive stars is seen. Known to astronomers as Hodge 301, it is about 20 million years old, or about 10 times older than R136. The more massive stars of Hodge 301 have therefore already exploded as supernovae, blasting material away at tremendous speed and creating a web of entangled filaments. More explosions will come soon - in astronomical terms - as three red supergiants are indeed present in Hodge 301 that will end their life in the gigantic firework of a supernova within the next million years. ESO PR Photo 13d/06 ESO PR Photo 13d/06 Gas Pillars in Tarantula Nebula While some stars are dying in this spidery cosmic inferno, others are yet to be born. Some structures, seen in the lower part of the image, have the appearance of elephant trunks, not unlike the famous and fertile "Pillars of Creation" at the top of which stars are forming. In fact, it seems that stars form all over the place in this gigantic stellar nursery and in all possible masses, at least down to the mass of our Sun. In some places, in a marvellous recycling process, it is the extreme radiation from the hot and massive stars and the shocks created by the supernova explosions that has compressed the gas to such extent to allow stars to form. To the right and slightly below the central cluster, a red bubble is visible. The star that blows the material making this bubble is thought to be 20 times more massive, 130 000 times more luminous, 10 times larger and 6 times hotter than our Sun. A possible fainter example of such a bubble is also visible just above the large red bubble in the image. ESO PR Photo 13e/06 ESO PR Photo 13e/06 Red Bubbles in Tarantula Nebula Earlier colour composite images of the Tarantula nebula have been made with other instruments and/or filters at ESO's telescopes, e.g. PR Photo 05a/00 in visual light with FORS2 at the VLT at Paranal, and PR Photos 14a-g/02 and 34a-h/04 with the Wide-Field Imager at the ESO/MPG 2.2-m telescope at La Silla.

2006-04-01

374

Statistical analysis of seismicity rate change in the Tokyo Metropolitan area due to the 2011 Tohoku Earthquake  

NASA Astrophysics Data System (ADS)

We examined a relationship between the Coulomb Failure Function (?CFF) due to the Tohoku earthquake (March 11, 2011; MJMA 9.0) and the seismicity rate change in Tokyo Metropolitan area following March 2011. Because of large variation in focal mechanism in the Kanto region, the receiver faults for the ?CFF were assumed to be two nodal planes of small (M ? 2.0) earthquakes which occurred before and after the Tohoku earthquake. The seismicity rate changes, particularly the rate increase, are well explained by ?CFF due to the gigantic thrusting, while some other possible factors (e.g., dynamic stress changes, excess of fluid dehydration) may also contribute the rate changes. Among 30,746 previous events provided by the National Research Institute for Earth Science and Disaster Prevention (M ? 2.0, July 1979 - July 2003), we used as receiver faults, almost 16,000 events indicate significant increase in ?CFF, while about 8,000 events show significant decrease. Positive ?CFF predicts seismicity rate increase in southwestern Ibaraki and northern Chiba prefectures where intermediate-depth earthquakes occur, and in shallow crust of the Izu-Oshima and Hakone regions. In these regions, seismicity rates significantly increased after the Tohoku earthquake. The seismicity has increased since March 2011 with respect to the Epidemic Type of Aftershock Sequence (ETAS) model (Ogata, 1988), indicating that the rate change was due to the stress increase by the Tohoku earthquake. The activated seismicity in the Izu and Hakone regions rapidly decayed following the Omori-Utsu formula, while the increased rate of seismicity in the southwestern Ibaraki and northern Chiba prefectures is still continuing. We also calculated ?CFF due to the 2011 Tohoku earthquake for the focal mechanism solutions of earthquakes between April 2008 and October 2011 recorded on the Metropolitan Seismic Observation network (MeSO-net). The ?CFF values for the earthquakes after March 2011 show more positive values than those before March 2011, supporting a triggering hypothesis that the 2011 Tohoku earthquake triggered the seismicity changes in the Kanto region.

Ishibe, T.; Sakai, S.; Shimazaki, K.; Satake, K.; Tsuruoka, H.; Nakagawa, S.; Hirata, N.

2012-12-01

375

Landslide disaster avoidance: learning from Leyte  

NASA Astrophysics Data System (ADS)

On 17 February 2006 a gigantic rockslide triggered a debris avalanche that overran the barangay Guinsaugon, St. Bernard in Southern Leyte Province, Philippines, burying 154 victims, with 990 missing including 246 school children. Even with satellite imagery, GIS-based landslide susceptibility modelling and real-time meteorological and seismic data analysis, scientific prediction of every potentially fatal landslide is not possible in most parts of the world. This is particular the case in steep, unstable, densely-populated country in which heavy rain is common. So how can further events of this type be prevented from turning into disasters? A number of precursory phenomena were noted by local inhabitants at Guinsaugon: a crack around the slope that failed was noticed in May 2005; coconut trees near the northern foot of the landslide scarp began to lean increasingly in the down-slope direction in December 2005; a slope around the northern edge of the 17 February 2006 landslide scarp failed on December 17, 2005; in the 9 days prior to the rockslide, 640 mm of rain fell; 450 mm in a 3-day period. Such phenomena are commonly reported by local inhabitants before large landslides (e.g. Elm, Mayunmarca, and many others). In many cases, therefore, it is in principle possible for local people to avoid the consequences of the landslide if they know enough to act appropriately in response to the precursory phenomena. For this possibility to be realized, appropriate information must be provided to and assimilated by the local population. Useful ways of achieving this include pamphlets, video, TV and radio programs and visits from civil defence personnel. The information must be properly presented; scientific language will be ineffective. A communication pyramid, leading from government agencies to local leaders, can facilitate the rapid availability of the information to all potentially susceptible communities. If science can determine those areas not vulnerable to landslide disasters, that is potentially advantageous. However the next landslide may be next week, so the information initiative cannot wait for science: lives will not be saved while the pamphlets are in a box. Keywords: Leyte landslide; precursory phenomena; disaster avoidance; community awareness.

Davies, T. R.

2006-12-01

376

Volcanic eruptions, global change and evolution of species  

NASA Astrophysics Data System (ADS)

Our group proposed in 1986 that the Deccan traps of India had been co-eval with the Cretaceous-Tertiary mass extinction, had lasted less than 800 kyears, straddling the KT. In 1995, Bhandari and colleagues showed that the iridium level marking the Chicxulub impact could be found in the Deccan and was sandwiched between flows, demonstrating that they were co-eval events but that volcanism had started first and could not be a consequence of impact. Since then, many groups have contributed to dating more precisely continental flood basalts around the world and found that there was almost a one to one correspondance between flood basalts and mass extinctions (but not impacts, except for the KT) : for a recent review see Courtillot and Renne (2003). In recent years, a number of significant advances have been made. It has been shown in the case of the historically large but geologically very small Icelandic Laki eruption of 1783 that such eruptions could inject large amounts of sulfate aerosols all the way to the stratosphere and have a global impact on climate : therefore, effusive basaltic volcanism on a large scale could alter climate (our group with Frédéric Fluteau and Anne-Lise Chenet and Steve Self with Thor Thordarson). Petrologic, volcanological, paleomagnetic, paleontological and geochronologic studies of the entire 3000m thick Deccan pile have been resumed (mainly our group, that of Self with Mike Widdowson and Anne Jay, and that of Gerta Keller). The result is that the thick lava pile actually erupted in a relatively small number of gigantic pulses (with mega-flows up to 10000 km3 in volume having erupted in decades !). Field evidence has been given that flows could extend over almost 1000km, and paleontological and K-Ar dating now reveals a history of mainly two mega-pulses having occurred, one just prior to the KT the second somewhat afterwards explaining the long delay of recovery of species from the catastrophe. There is little doubt now that the KT catastrophe would have occurred even if the impact (which did have a significant additionnal effect) had not struck, and that the impact could not have generated a mass extinction if volcanism had not already been going on. Finally, global change during these periods of anomalous volcanism may provide interesting benchmarks for modelling of more current potential global change, and geologists be a major help to climate modelers.

Courtillot, V.

2007-12-01

377

Larger than life: billboard communication in Southeast Asia.  

PubMed

Billboards are widely used in Southeast Asia, and especially in Malaysia, Singapore, Indonesia, and Thailand, for delivering persuasive political and commercial messages and for advertising the cinema. Billboards are a cost effective way of communicating with all segments of society including illiterate persons, poor people who cannot afford television sets and radios, rural populations, and diverse ethnic and linguistic groups. Billboards are a form of applied art and are used to deliver temporary messages. Each country has its own billboard traditions and styles, and within each country, commercial, cinema, and political boards also have their own styles. In Indonesia and Thailand, almost all billboards are hand painted and gigantic in size. The paintings are highly realistic and detailed. In Thailand billboards are produced in large studios employing many artists, and the boards cost about US$9.00/square meter or more. The Four Art Studio in Bankok produces commercial boards in Renaissance, Impressionistic, Pop, and Op art styles. Both Indonesia and Thailand were early centers of artistic and cultural influence in Asia, and each country has highly developed art traditions. In Indonesia, the Japanese occupation led to the development of propaganda and nationalistic art. After independence nationalistic art was developed still further. At the present time, socialist-realistism predominates as an art style, and large air brushed political billboards are prominantly displayed throughout the country. In Malaysia and Singapore billboards are small in size. Most of the boards, except those used to advertise the cinema, are printed rather than painted. Neither country has a strong tradition of art. Realism is not stressed in their fine arts nor in their art training. The lack of a realistic art tradition probably accounts for the emphasis placed on printed billboards. Cinema boards are painted but they are not produced by applied artists and are generally mediocre in quality. Political boards in Malaysia generally contain only verbal messages. In Singapore there are few political billboards. In Japan billboards are also widely used. They are sophisticated and usually printed with advanced technological methods. An innovative form of billboard, a 20 meter audiovisual screen, is appearing more and more frequently in Japanese cities. PMID:12339664

Barnard, B

1983-01-01

378

[Hands and feet of prosimians primates. Attempts of morphologic characterization].  

PubMed

The length of the carpus and tarsus, the metacarpus and metatarsus, the fingers and toes of 142 prosimian apes was measured. The relationship expressed as a percentage was drawn up for each individual between the length of each osseous part and that of its third metacarpal in order to eliminate the differences related to the size of the rest of the body. This ratio was compared with that of man. The characteristic variations appeared at the level of the subfamilies. CONCERNING THE HAND: The carpus presented the same values as that of man except for that of the indris, which was shorter. The thumb had proportionally the same length as that of man, sometimes longer and sometimes smaller as in the Eulemurs, Hapalidea, Megalapidea, Indrises, Daubentonia and Perodictus. The different metacarpals, including the fourth, were a little shorter than the third. In these subfamilies, the second ray was also often shorter and even much shorter in the Megalapidea and the Perodictus. The other rays were a little longer, in particular the fourth which could exceed the third in rather many subfamilies. CONCERNING THE FOOT: The length of the tarsus was extremely variable. It was twice larger in the Galagoidae, definitely larger in the tarsius and discreetly in the Hapalidae, a little smaller in the other Lemurs and much smaller in the other Prosimian apes, joining in that the near totality of the simians. The hallux was proportionally as long as that of man and sometimes even longer. The metatarsals were sometimes a little longer, sometimes less long, but always appreciably of the same length between them. The other toes were short at the aye aye (daubentonia), of which the foot appeared even smaller than that of man. The toes of the other prosimious resembled much to the fingers and in the propithecus and the perodictus, the fourth took gigantic proportions. There has been establishment of an anatomical relation and functional calculus between the length of the last three rays of the hands and the feet of prosimian apes and the biomechanics of their trapezometacarpal and their first cuneometacarpal joints. PMID:18815065

Kuhlmann, J N

2008-08-01

379

Accretionary history of the Altai-Mongolian terrane: perspectives from granitic zircon U-Pb and Hf-isotope data  

NASA Astrophysics Data System (ADS)

The Central Asian Orogenic Belt (CAOB) consists of many tectonic terranes with distinct origin and complicated evolutionary history. Understanding of individual block is crucial to reconstruct the geodynamic history of the gigantic accetionary collage. This study presents zircon U-Pb ages and Hf isotopes for the granitoid rocks in the Russian Altai mountain range (including Gorny Altai, Altai-Mongolian terrane and CTUS suture zone between them), in order to clarify the timing of granitic magmatism, source nature, continental crustal growth and tectonic evolution. Our dating results suggest that granitic magmatism of the Russian Altai mountain range occurred in three major episodes including 445~429 Ma, 410~360 Ma and ~241 Ma. Most of the zircons within the Paleozoic granitoids present comparable positive ?Hf(t) values and Neoproterozoic crustal model ages, which favor the interpretation that the juvenile crustal materials produced in the early stage of CAOB were probably dominant sources for the Paleozoic magmatism in the region. The inference is also supported by widespread occurrence of short-lived juvenile materials including ophiolites, seamount relics and arc assemblages in the north CAOB. Consequently, the Paleozoic massive granitic rocks maybe not represent continental crustal growth at the time when they were emplaced, but rather record reworking of relatively juvenile Proterozoic crustal rocks although mantle-derived mafic magma was possibly involved to sever as heat engine during granitic magma generation. The Early Triassic granitic intrusion may be product in an intra-plate environment, as the case of same type rocks in the adjacent areas. The positive ?Hf(t) values (1.81~7.47) and corresponding Hf model ages (0.80~1.16 Ga) together with evidence of petrology are consistent with the interpretation that the parental magma of the Triassic granitic intrusion was produced from enriched mantle-derived sources under an usually high temperature condition which is likely due to basaltic magma that underplated the lower crust. Our data combined with evidence of the regional geology enable us to conclude that the Gorny Altai and Altai-Mongolian terranes possibly have similar tectonic natures, but represent two separate accretionary systems before Devonian collision. The accretion and amalgamation processes resulted in the Paleozoic granitoid magmatism and caused the two terranes to merge as a composite tectonic domain at the Siberian continental margin.

Cai, Keda; Sun, Min; Xiao, Wenjiao

2014-05-01

380

Possibility of unlimited shear displacement due to sliding-surface-liquefaction of MH gasification and long runout submarine landslides  

NASA Astrophysics Data System (ADS)

Recent studies on the mechanism of occurrence of large scale submarine landslides focuses mostly on the generation of excess pore pressure due to rapid sedimentation rate in certain environment, rather than gasification of methane hydrates (MH), although MH gasification could contribute to the landslides in the transgresssion period. However, at the 1896 Meiji Sanriku-oki Earthquake which caused serious tsunami disaster in the Tohoku region of Japan, there are witnesses of large-scale flame which were of possibly ejected dissolved methane hydrates (MH) from sea floor. We employed the stress-controlled undrained ring shear apparatuses have been developed at Disaster Prevention Research Institute, Kyoto University to reproduce shear behavior of the dry sand-dry ice mixture under constant normal stress and shear speed control tests using the latest ring shear apparatus. Tested 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. Through three series of tests, we obtained following results. (1) Rate Effect: The samples were tested under stepped shear speed ranging from 0.02 cm/s to 10 cm/s. The obtained excess pore-pressure ratio relationship, which is defined as the ratio of excess pore air pressure to initial effective stress, These results clearly shows positive speed dependency, especially for 1 cm/s and 10 cm/s. This phenomenon could be explained by the "sliding surface liquefaction." (2) Difference between internal and external friction: Based on the published observation of the sliding surface and the BSR, the sliding surface can be generated in the boundary of the MH layer. Tests to compare the internal friction and external friction between sand layers reveals that the behaviour of the both conditions have no significant difference. (3) Shear behaviour under cyclic loading condition: Above-mentioned sliding-surface-liquefaction in the sand - dry ice mixture supports the possibility of similar accelerating and unlimited displacement in the sand-MH mixture or boundaries between MH and sand layer induced by certain strong ground motion under sea floor. To simulate the earthquake-induced submarine landslides due to gasification of MH, authors applied the simple sine-curve cyclic loading to the sand-dry ice sample. After certain number of cyclic loading, sliding surface liquefaction appeared. When the mobilized shear resistance reduced by such excess pore pressure becomes smaller than the shear stress, accelerating behavior and unlimited shear displacement could be expected. Thus, MH still has high possibility to cause gigantic submarine landslides under certain strong earthquake condition.

Tsukui, A.; Fukuoka, H.; Yamasaki, S.

2012-04-01

381

Benthic foraminifera as tools in interpretation of subsurface hydrocarbon fluid flow at Veslemøy High and Hola-Vesterålen areas of the Barents Sea.  

NASA Astrophysics Data System (ADS)

Relatively few studies have focused on high-latitude benthic foraminifera related to hydrocarbon seeps. In this study, we present micropaleontological data from 8 gravity cores from the Veslemøy High and 4 surface sediments (0-1cm) from Hola-Vesterålen, Norway. The study of hydrocarbon impregnation and its effect on benthic foraminfera was conducted on selected sediment samples from the calcium-rich Holocene sediments of the Veslemøy High. The assemblage of foraminifera have been identified from three regional clusters. Cluster I and II are dominated by benthic foraminifera Buccella, Cassidulina, Cibicides, Discopulvinulina, Epistominella, Pullenia and Trifarina. Cluster III is distinct with an elevated abundance of Cassidulina, Cibicides and Trifarina with significant (>5 %) occurrence of Nonionella and Uvigerina. There is no apparent dissolution on the preserved foraminifera. However, there can be differential dissolution or destruction of the more fragile (thinner-walled test) species like Epistominella, Nonionella or Pullenia while leaving behind over-represented species like Cibicides or Trifarina (both preferring coarse grained, high energy areas that can withstand permanent winnowing and redeposition) with higher preservation potential. Also, Cluster III is placed right over the underlying fault line with shallow seep-indications and thus the fluids released may have induced the dissolution of the fragile species. Moreover, the significant occurrence of benthic foraminifera Nonionella auris, and Uvigerina peregrina, in Holocene deposits of Cluster III may be indicative of environments influenced by hydrocarbon migration to the seafloor. Previous studies have reported active natural hydrocarbon seepage in the Hola area and the stable carbon and hydrogen isotopic composition of methane in the sediments suggests a predominantly thermogenic methane source. The seep-assemblage is composed of Cibicides (~60%), Cassidulina, Discanomalina, Textularia and Trifarina. Discanomalina coronata is an indicator species to identify active cold-water coral mounds. A negative carbon isotopic signal is recorded by D. coronata in all samples. Seep samples with low diversities also contain deformed individuals of Cibicides lobatulus (3.4-6.5 %), similar to those reported for a gigantic oil spill from a tanker or for environments polluted with heavy metals. However, it is an attached form and thus its test shape is affected by the nature of the substratum. Carbon isotopic signature of the deformed specimens reveal slightly lower values than their undeformed counterparts. One sample from Ullsfjorden was also studied where the assemblage is represented by Bulimina, Cassidulina, Globobulimina, Melonis, Nonionella and Reophax. Infaunal fauna B. marginata, M. barleeanum, and N. labradorica prefer muddy/silty to sandy substrata and high organic matter input, and thrive under suboxic-dysoxic conditions. All species in this assemblage have recorded negative carbon isotopic signal.

Baranwal, Soma; Sauer, Simone; Knies, Jochen; Chand, Shyam; Jensen, Henning; Klug, Martin

2014-05-01

382

The origins of dragon-kings and their occurrence in society  

NASA Astrophysics Data System (ADS)

A society is a medium with a complex structure of one-to-one relations between people. Those could be relations between friends, wife-husband relationships, relations between business partners, and so on. At a certain level of analysis, a society can be regarded as a gigantic maze constituted of one-to-one relationships between people. From a physical standpoint it can be considered as a highly porous medium. Such media are widely known for their outstanding properties and effects like self-organized criticality, percolation, power-law distribution of network cluster sizes, etc. In these media supercritical events, referred to as dragon-kings, may occur in two cases: when increasing stress is applied to a system (self-organized criticality scenario) or when increasing conductivity of a system is observed (percolation scenario). In social applications the first scenario is typical for negative effects: crises, wars, revolutions, financial breakdowns, state collapses, etc. The second scenario is more typical for positive effects like emergence of cities, growth of firms, population blow-ups, economic miracles, technology diffusion, social network formation, etc. If both conditions (increasing stress and increasing conductivity) are observed together, then absolutely miraculous dragon-king effects can occur that involve most human society. Historical examples of this effect are the emergence of the Mongol Empire, world religions, World War II, and the explosive proliferation of global internet services. This article describes these two scenarios in detail beginning with an overview of historical dragon-king events and phenomena starting from the early human history till the last decades and concluding with an analysis of their possible near future consequences on our global society. Thus we demonstrate that in social systems dragon-king is not a random outlier unexplainable by power-law statistics, but a natural effect. It is a very large cluster in a porous percolation medium. It occurs as a result of changes in external conditions, such as supercritical load, increase in system elements’ sensitivity, or system connectivity growth.

Malkov, Artemy; Zinkina, Julia; Korotayev, Andrey

2012-11-01

383

Assessing Glacier Hazards At Ghiacciaio Del Belvedere, Macugnaga, Italian Alps  

NASA Astrophysics Data System (ADS)

The uppermost section of the Valle Anzasca behind and above the community of Macugnaga in the Italian Alps is one of the most spectacular high-mountain land- scapes in Europe, with gigantic rock walls and numerous steep hanging glaciers. Its main glacier, Ghiacciaio del Belvedere at the foot of the huge Monte Rosa east face, is a heavily debris-covered glacier flowing on a thick sediment bed. Problems with floods, avalanches and debris flows from this ice body have been known for extended time periods. Most recently, however, the evolution of this highly dynamic environ- ment has become more dramatic. An outburst of Lago delle Locce, an ice-dammed lake at the confluenec of the tributary Ghiacciaio delle Locce with Ghiacciaio del Belvedere, caused heavy damage in 1979 and necessitated site investigation and con- struction work to be done for flood protection. The intermittent glacier growth ten- dency in the 1970es induced strong bulging of the glacier surface and, in places, caused the glacier tongue to override historical morains and to destroy newly-grown forest stands. A surge-type flow acceleration started in the lower parts of the Monte- Rosa east face during summer 2000, leading to strong crevassing and deformation of Ghiacciaio del Belvedere and extreme bulging of its orographic right margin. High water pressure and accelerated movement lasted into winter 2001/2002: the ice now started overriding the LIA moraine near Rifugio Zamboni of the CAI. In addition but rather independently, a most active detachment zone for rock falls and debris flows developed for several years now in the east face of Monte Rosa, somewhat more to the south of the accelerated glacier movement and at an altitude where relatively warm permafrost must be expected. Besides the scientific interest in these phenomena, the growing hazard potential to the local infrastructure must be considered seriously. Es- pecially potentials for the destabilization of large rock and ice masses in the east face of Monte Rosa, for interruption of the access trail to the Rifugio Zamboni by overrid- ing and/or collapse of the lateral moraine, for impacts by ice invading various instal- lations (cable car, restaurant, ski runs, trails) near the moraine hill of Belvedere, and for sudden outbursts of pressurized subglacial water or the newly formed supraglacial lake must be envisaged.

Haeberli, W.; Chiarle, M.; Mortara, G.; Mazza, A.

384

Enhancement and Extension of Porosity Model in the FDNS-500 Code to Provide Enhanced Simulations of Rocket Engine Components  

NASA Technical Reports Server (NTRS)

In the past, the design of rocket engines has primarily relied on the cold flow/hot fire test, and the empirical correlations developed based on the database from previous designs. However, it is very costly to fabricate and test various hardware designs during the design cycle, whereas the empirical model becomes unreliable in designing the advanced rocket engine where its operating conditions exceed the range of the database. The main goal of the 2nd Generation Reusable Launching Vehicle (GEN-II RLV) is to reduce the cost per payload and to extend the life of the hardware, which poses a great challenge to the rocket engine design. Hence, understanding the flow characteristics in each engine components is thus critical to the engine design. In the last few decades, the methodology of computational fluid dynamics (CFD) has been advanced to be a mature tool of analyzing various engine components. Therefore, it is important for the CFD design tool to be able to properly simulate the hot flow environment near the liquid injector, and thus to accurately predict the heat load to the injector faceplate. However, to date it is still not feasible to conduct CFD simulations of the detailed flowfield with very complicated geometries such as fluid flow and heat transfer in an injector assembly and through a porous plate, which requires gigantic computer memories and power to resolve the detailed geometry. The rigimesh (a sintered metal material), utilized to reduce the heat load to the faceplate, is one of the design concepts for the injector faceplate of the GEN-II RLV. In addition, the injector assembly is designed to distribute propellants into the combustion chamber of the liquid rocket engine. A porosity mode thus becomes a necessity for the CFD code in order to efficiently simulate the flow and heat transfer in these porous media, and maintain good accuracy in describing the flow fields. Currently, the FDNS (Finite Difference Navier-Stakes) code is one of the CFD codes which are most widely used by research engineers at NASA Marshall Space Flight Center (MSFC) to simulate various flow problems related to rocket engines. The objective of this research work during the 10-week summer faculty fellowship program was to 1) debug the framework of the porosity model in the current FDNS code, and 2) validate the porosity model by simulating flows through various porous media such as tube banks and porous plate.

Cheng, Gary

2003-01-01

385

MCNP5 and GEANT4 comparisons for preliminary Fast Neutron Pencil Beam design at the University of Utah TRIGA system  

NASA Astrophysics Data System (ADS)

The main objective of this thesis is twofold. The starting objective was to develop a model for meaningful benchmarking of different versions of GEANT4 against an experimental set-up and MCNP5 pertaining to photon transport and interactions. The following objective was to develop a preliminary design of a Fast Neutron Pencil Beam (FNPB) Facility to be applicable for the University of Utah research reactor (UUTR) using MCNP5 and GEANT4. The three various GEANT4 code versions, GEANT4.9.4, GEANT4.9.3, and GEANT4.9.2, were compared to MCNP5 and the experimental measurements of gamma attenuation in air. The average gamma dose rate was measured in the laboratory experiment at various distances from a shielded cesium source using a Ludlum model 19 portable NaI detector. As it was expected, the gamma dose rate decreased with distance. All three GEANT4 code versions agreed well with both the experimental data and the MCNP5 simulation. Additionally, a simple GEANT4 and MCNP5 model was developed to compare the code agreements for neutron interactions in various materials. Preliminary FNPB design was developed using MCNP5; a semi-accurate model was developed using GEANT4 (because GEANT4 does not support the reactor physics modeling, the reactor was represented as a surface neutron source, thus a semi-accurate model). Based on the MCNP5 model, the fast neutron flux in a sample holder of the FNPB is obtained to be 6.52×107 n/cm2s, which is one order of magnitude lower than gigantic fast neutron pencil beam facilities existing elsewhere. The MCNP5 model-based neutron spectrum indicates that the maximum expected fast neutron flux is at a neutron energy of ~1 MeV. In addition, the MCNP5 model provided information on gamma flux to be expected in this preliminary FNPB design; specifically, in the sample holder, the gamma flux is to be expected to be around 108 ?/cm 2s, delivering a gamma dose of 4.54×103 rem/hr. This value is one to two orders of magnitudes below the gamma exposure as exists in the currently used fast neutron irradiation facility at the UUTR. The GEANT4.9.4 semi-accurate model of the FNPB design provided higher values for neutron and gamma fluxes, indicating the importance of transfering the data from MCNP5 rather than using the GEANT4 default neutron spectra.

Adjei, Christian Amevi

386

E-CANES: A Research Network dedicated to Electromagnetic Coupling of the Atmosphere With Near-Earth Space  

NASA Astrophysics Data System (ADS)

Transient luminous events in the stratosphere and mesosphere, the sprites, elves, blue jets and gigantic jets, are observed above intense thunderstorms in association with particularly intense lightning discharges. Their recent discovery (1989) offers an opportunity to study the fundamental process of the electric discharge under the different conditions of the troposphere (lightning), stratosphere (blue jets) and the mesosphere (sprites) and the coupling between these regions by electric and magnetic fields. It further facilitates studies of the more general questions of thunderstorm effects on the atmosphere and the role of thunderstorms in a changing climate. New space missions will be launched in the coming years to study the various effects of thunderstorms. They will focus on transient luminous events, the generation of relativistic electron beams in discharges, and the perturbation to the atmosphere, ionosphere and magnetosphere of lightning, transient luminous events, water vapour transport and gravity waves. The missions are the French micro-satellite TARANIS, the ESA ASIM payload on board the International Space Station and the Japanese Sprite Sat mission. These highly interdisciplinary missions will result in a wealth of new data, which require knowledge based capacity building to underpin the observations with improved statistical data analysis and theoretical modelling. We are therefore establishing a global framework for research on thunderstorm processes and their effect on the atmosphere, in particular (1) the fundamental process of the electric discharge as manifested in the stratosphere and mesosphere as sprites and jets, (2) the relationship between cosmic rays, lightning discharges, transient luminous events and terrestrial gamma ray flashes, and (3) the environmental impact of the above physical processes, and thunderstorms in general, on the atmosphere and near-Earth space. The first step has been the creation of the European research group (GDRE) dubbed E-CANES (Electromagnetic Coupling of the Atmosphere with the Near-Earth Space). It complements in a synergistic way the former EU Research Training Network 'Coupling of Atmospheric Layers', the existing COST action on 'The physics of lightning flash and its effects', the ASIM Topical Team, and other programs. The main objective of E-CANES is to initiate and promote coordination activities towards a global research community on the subject. The first actions include the establishment of an organization for coordinating ground, balloon and aircraft observation campaigns, the creation of a community-wide mailing list and website, and the promotion and coordination of joint activities with other structures - to include new communities and to avoid the duplication of meetings and workshops.

Hanuise, C.; Blanc, E.; Crosby, N.; Ebert, U.; Mareev, E.; Neubert, T.; Rothkaehl, H.; Santolik, O.; Yair, Y.; Gille, P.

2008-12-01

387

Acromegaly resolution after traumatic brain injury: a case report  

PubMed Central

Introduction Anterior hypopituitarism is a common complication of head trauma, with a prevalence of 30% to 70% among long-term survivors. This is a much higher frequency than previously thought and suggests that most cases of post-traumatic hypopituitarism remain undiagnosed and untreated. Symptoms of hypopituitarism are very unspecific and very similar to those in traumatic brain injury patients in general, which makes hypopituitarism difficult to diagnose. The factors that predict the likelihood of developing hypopituitarism following traumatic brain injury remain poorly understood. The incidence of a specific hormone deficiency is variable, with growth hormone deficiency reported in 18% to 23% of cases. Case presentation A 23-year-old Hispanic man with a 2-year history of hypertension and diabetes presented with severe closed-head trauma producing diffuse axonal injury, subarachnoid hemorrhage and a brain concussion. A computed tomography scan showed a pituitary macroadenoma. The patient has clinical features of acromegaly and gigantism without other pituitary hyperfunctional manifestations or mass effect syndrome. A short-term post-traumatic laboratory test showed high levels of insulin like growth factor 1 and growth hormone, which are compatible with a growth hormone–producing pituitary tumor. At the third month post-trauma, the patient’s levels of insulin like growth factor 1 had decreased to low normal levels, with basal low levels of growth hormone. A glucose tolerance test completely suppressed the growth hormone, which confirmed resolution of acromegaly. An insulin tolerance test showed lack of stimulation of growth hormone and cortisol, demonstrating hypopituitarism of both axes. Conclusion Even though hypopituitarism is a frequent complication of traumatic brain injury, there are no reports in the literature, to the best of my knowledge, of patients with hyperfunctional pituitary adenomas, such as growth hormone–producing adenoma, that resolved after head trauma. A clear protocol has not yet been established to identify which patients should be screened for hypopituitarism. Predictive factors that might determine the likelihood of developing post-traumatic hypopituitarism have not been clearly established, but there is no evidence of the presence of pituitary adenomas as a risk factor in otherwise healthy patients. PMID:25182385

2014-01-01

388

Nanomechanical molecular devices made of DNA origami.  

PubMed

CONSPECTUS: Eight years have passed since the striking debut of the DNA origami technique ( Rothemund, P. W. K. Nature 2006 , 440 , 297 - 302 ), in which long single-stranded DNA is folded into a designed nanostructure, in either 2D or 3D, with the aid of many short staple strands. The number of proposals for new design principles for DNA origami structures seems to have already reached a peak. It is apparent that DNA origami study is now entering the second phase of creating practical applications. The development of functional nanomechanical molecular devices using the DNA origami technique is one such application attracting significant interest from researchers in the field. Nanomechanical DNA origami devices, which maintain the characteristics of DNA origami structures, have various advantages over conventional DNA nanomachines. Comparatively high assembly yield, relatively large size visible via atomic force microscopy (AFM) or transmission electron microscopy (TEM), and the capability to assemble multiple functional groups with precision using multiple staple strands are some of the advantages of the DNA origami technique for constructing sophisticated molecular devices. This Account describes the recent developments of such nanomechanical DNA origami devices and reviews the emerging target of DNA origami studies. First, simple "dynamic" DNA origami structures with transformation capability, such as DNA origami boxes and a DNA origami hatch with structure control, are briefly summarized. More elaborate nanomechanical DNA origami devices are then reviewed. The first example describes DNA origami pinching devices that can be used as "single-molecule" beacons to detect a variety of biorelated molecules, from metal ions at the size of a few tens of atomic mass number units to relatively gigantic proteins with a molecular mass greater than a hundred kilodaltons, all on a single platform. Clamshell-like DNA nanorobots equipped with logic gates can discriminate different cell lines, open their shell, and bind to their target. An intelligent DNA origami "sheath" can mimic the function of suppressors in a transcription regulation system to control the expression of a loaded gene. DNA origami "rolls" are created to construct precisely arranged plasmonic devices with metal nanoparticles. All of their functions are derived from their nanomechanical movement, which is programmable by designing the DNA sequence or by using the significant repository of technical achievements in nucleic acid chemistry. Finally, some studies on detailed structural parameters of DNA origami or their mechanical properties in nanoscale are discussed, which may be useful and inspiring for readers who intend to design new nanomechanical DNA origami devices. PMID:24772996

Kuzuya, Akinori; Ohya, Yuichi

2014-06-17

389

ISM abundances and history: a 3D, solar neighborhood view  

NASA Astrophysics Data System (ADS)

For observational reasons, the solar neighborhood is particularly suitable for the study of the multi-phase interstellar (IS) medium and the search for traces of its temporal evolution. On the other hand, by a number of aspects it seems to be a peculiar region. We use recent 3D maps of the IS dust based on color excess data as well as former maps of the gas to illustrate how such maps can be used to shed additional light on the specificity of the local medium, its history and abundance pattern. 3D maps reveal a gigantic cavity located in the third quadrant and connected to the Local Bubble, the latter itself running into an elongated cavity toward l? 70°. Most nearby cloud complexes of the so-called Gould belt but also more distant clouds seem to border a large fraction of this entire structure. The IS medium with the large cavity appears ionized and dust-poor, as deduced from ionized calcium and neutral sodium to dust ratios. The geometry favors the proposed scenario of Gould belt-Local Arm formation through the braking of a supercloud by interaction with a spiral density wave \\citep{olano01}. The highly variable D/H ratio in the nearby IS gas may also be spatially related to the global structure. We speculate about potential consequences of the supercloud encounter and dust-gas decoupling during its braking, in particular the formation of strong inhomogeneities in both the dust to gas abundance ratio and the dust characteristics: (i) during the ? 500 Myrs prior to the collision, dust within the supercloud may have been gradually, strongly enriched in D due to an absence of strong stellar formation and preferential adsorption of D \\citep{jura82,draine03} ; (ii) during its interaction with the Plane and the braking dust-rich and dust-poor regions may have formed due to differential gas drag, the dust being more concentrated in the dense areas; strong radiation pressure from OB associations at the boundary of the left-behind giant cavity may have also helped in emptying the cavity from its dust at the profit of the central parts of the supercloud ; (iii) present D/H variations could be due to the combination of those dust inhomogeneities and posterior, localized deuterium release by grains in recent star forming regions. In this case, the true local D/H ratio has an intermediate value within the observed range.

Lallement, R.; Vergely, J.-L.; Puspitarini, L.

390

A review on anthropogenic impact to the Micro Prespa lake and its damages  

NASA Astrophysics Data System (ADS)

Paper presents the results of the integrated and multidisciplinary studies for investigation of the anthropogenic damages to Albanian part of the transborder Micro Prespa Lake. Remote sensing with Landsat images was used for identification of environmental changes in time for the period 1970 - 2010. Micro Prespa Lake is lake with international status, as Ramsar Convection, International Park and Special Protection Area-79/409/EEC. According to the studies, investigations and analyses, the following were concluded: Devolli River- Micro Prespa Lake irrigation system was not scientifically supported by environmental engineering, hydroeconomy and International Rights principles. It does work according to the projected parameters, and also, doesn't supply the agricultural needs. About of 10 % of the water volume, discharges by Devolli River in Micro Prespa Lake during the winter, is taken from this lake for the irrigation in summer. Great surface of Albanian part of Micro Prespa Lake is destroyed. The other part of the lake is atrophied and the habitat and biodiversity are damaged. Important and unique species of fish, birds and plants of national and international values are risked. The underground karstic connection ways for water circulation are blocked. There are ruining the historic values of the area, such the encient Treni cave from the Bronze Age. The Albanian part of the Micro Prespa Lake has been damaged by the human activities. A huge amount of 1,2 million cubic meters alluvium has been deposited on the lake bottom and lakeshore, which was transported by the Devolli River waters, since 1974. This river waters, rich in alluvium and organic coal material from outcropped geological formations, also absorbed free chemical toxic remains by the drainage of Devolli farm ground, which have changed the chemical features of the lake water and degrading it. Micro Prespa Lake communicates with Macro Prespa Lake, and together with Ohrid Lake. Blockage of underground karstic connection ways has diminished not only the components of the lake water balance, but also the decreasing yield of the underground springs, that supply the Ohrid lake and drinkable water springs. The Albanian part of the Micro Prespa Lake plays the role of a gigantic decanter. This is an unprecedented case, not only in Albanian but also in Balkan and World hydrography. Devolli river alluvium deposited in Micro Prespa Lake caused the otherwise of territory of Republic of Albania in this area. Albania will not have any part in this lake after some years. The social and public opinion in Albania, must be conscious for the otherwise of Albanian territory, which in the case of Micro Prespa Lake has a national and international negative effect on destructions of a transborder lake, defendey by Europian Convents.

Frasheri, N.; Pano, N.; Frasheri, A.; Beqiraj, G.; Bushati, S.; Taska, E.

2012-04-01

391

Brazilian and Mexican experiences in the study of incipient domestication  

PubMed Central

Background Studies of domestication enables a better understanding of human cultures, landscape changes according to peoples’ purposes, and evolutionary consequences of human actions on biodiversity. This review aimed at discussing concepts, hypotheses, and current trends in studies of domestication of plants, using examples of cases studied in regions of Mesoamerica and Brazil. We analyzed trends of ethnobiological studies contributing to document processes of domestication and to establish criteria for biodiversity conservation based on traditional ecological knowledge. Methods Based on reviewing our own and other authors’ studies we analyzed management patterns and evolutionary trends associated to domestication occurring at plant populations and landscape levels. Particularly, we systematized information documenting: ethnobotanical aspects about plant management and artificial selection mechanisms, morphological consequences of plant management, population genetics of wild and managed plant populations, trends of change in reproduction systems of plants associated to management, and other ecological and physiological aspects influenced by management and domestication. Results Based on the analysis of study cases of 20 native species of herbs, shrubs and trees we identified similar criteria of artificial selection in different cultural contexts of Mexico and Brazil. Similar evolutionary trends were also identified in morphology (selection in favor of gigantism of useful and correlated parts); organoleptic characteristics such as taste, toxicity, color, texture; reproductive biology, mainly breeding system, phenological changes, and population genetics aspects, maintenance or increasing of genetic diversity in managed populations, high gene flow with wild relatives and low structure maintained by artificial selection. Our review is a first attempt to unify research methods for analyzing a high diversity of processes. Further research should emphasize deeper analyses of contrasting and diverse cultural and ecological contexts for a better understanding of evolution under incipient processes of domestication. Conclusion Higher research effort is particularly required in Brazil, where studies on this topic are scarcer than in Mexico but where diversity of human cultures managing their also high plant resources diversity offer high potential for documenting the diversity of mechanisms of artificial selection and evolutionary trends. Comparisons and evaluations of incipient domestication in the regions studied as well as the Andean area would significantly contribute to understanding origins and diffusion of the experience of managing and domesticating plants. PMID:24694009

2014-01-01

392

Solar and Drag Sail Propulsion: From Theory to Mission Implementation  

NASA Technical Reports Server (NTRS)

Solar and drag sail technology is entering the mainstream for space propulsion applications within NASA and around the world. Solar sails derive propulsion by reflecting sunlight from a large, mirror- like sail made of a lightweight, reflective material. The continuous sunlight pressure provides efficient primary propulsion without the expenditure of propellant or any other consumable, allowing for very high V maneuvers and long-duration deep space exploration. Drag sails increase the aerodynamic drag on Low Earth Orbit (LEO) spacecraft, providing a lightweight and relatively inexpensive approach for end-of-life deorbit and reentry. Since NASA began investing in the technology in the late 1990's, significant progress has been made toward their demonstration and implementation in space. NASA's Marshall Space Flight Center (MSFC) managed the development and testing of two different 20-m solar sail systems and rigorously tested them under simulated space conditions in the Glenn Research Center's Space Power Facility at Plum Brook Station, Ohio. One of these systems, developed by L'Garde, Inc., is planned for flight in 2015. Called Sunjammer, the 38m sailcraft will unfurl in deep space and demonstrate solar sail propulsion and navigation as it flies to Earth-Sun L1. In the interim, NASA MSFC funded the NanoSail-D, a subscale drag sail system designed for small spacecraft applications. The NanoSail-D flew aboard the Fast Affordable Science and Technology SATellite (FASTSAT) in 2010, also developed by MSFC, and began its mission after it was was ejected from the FASTSAT into Earth orbit, where it remained for several weeks before deorbiting as planned. NASA recently selected two small satellite missions as part of the Advanced Exploration Systems (AES) Program, both of which will use solar sails to enable their scientific objectives. Lunar Flashlight, managed by JPL, will search for and map volatiles in permanently shadowed Lunar craters using a solar sail as a gigantic mirror to steer sunlight into the shaded craters. The Near Earth Asteroid (NEA) Scout mission will use the sail as primary propulsion allowing it to survey and image one or more NEA's of interest for possible future human exploration. Both are planned for launch in 2017. As the technology matures, solar sails will increasingly be used to enable science and exploration missions that are currently impossible or prohibitively expensive using traditional chemical and electric rockets. For example, the NASA Heliophysics Decadal Survey identifies no less than three such missions for possible flight before the mid-2020's. Solar sail propulsion technology is no longer an intesting theoretical possibility; it has been demonstrated in space and is now a critical technology for science and solar system exploration.

Johnson, Les; Alhorn, Dean; Boudreaux, Mark; Casas, Joe; Stetson, Doug; Young, Roy

2014-01-01

393

Nanotechnology in agriculture: prospects and constraints  

PubMed Central

Attempts to apply nanotechnology in agriculture began with the growing realization that conventional farming technologies would neither be able to increase productivity any further nor restore ecosystems damaged by existing technologies back to their pristine state; in particular because the long-term effects of farming with “miracle seeds”, in conjunction with irrigation, fertilizers, and pesticides, have been questioned both at the scientific and policy levels, and must be gradually phased out. Nanotechnology in agriculture has gained momentum in the last decade with an abundance of public funding, but the pace of development is modest, even though many disciplines come under the umbrella of agriculture. This could be attributed to: a unique nature of farm production, which functions as an open system whereby energy and matter are exchanged freely; the scale of demand of input materials always being gigantic in contrast with industrial nanoproducts; an absence of control over the input nanomaterials in contrast with industrial nanoproducts (eg, the cell phone) and because their fate has to be conceived on the geosphere (pedosphere)-biosphere-hydrosphere-atmosphere continuum; the time lag of emerging technologies reaching the farmers’ field, especially given that many emerging economies are unwilling to spend on innovation; and the lack of foresight resulting from agricultural education not having attracted a sufficient number of brilliant minds the world over, while personnel from kindred disciplines might lack an understanding of agricultural production systems. If these issues are taken care of, nanotechnologic intervention in farming has bright prospects for improving the efficiency of nutrient use through nanoformulations of fertilizers, breaking yield barriers through bionanotechnology, surveillance and control of pests and diseases, understanding mechanisms of host-parasite interactions at the molecular level, development of new-generation pesticides and their carriers, preservation and packaging of food and food additives, strengthening of natural fibers, removal of contaminants from soil and water, improving the shelf-life of vegetables and flowers, clay-based nanoresources for precision water management, reclamation of salt-affected soils, and stabilization of erosion-prone surfaces, to name a few. PMID:25187699

Mukhopadhyay, Siddhartha S

2014-01-01

394

The soil-air exchange characteristics of total gaseous mercury from a large-scale municipal landfill area  

NASA Astrophysics Data System (ADS)

The cycle of mercury (Hg) from a gigantic landfill area (area ˜2.72 km 2) was investigated by conducting micrometeorological measurements of its exchange rates across soil-air boundary during the spring season of 2000. Based on this field campaign, we attempted to provide various insights into the Hg exchange processes, especially with respect to the decoupling of the mixed signatures of complex source processes. According to our analysis, the cycle of Hg in the study site appeared to be affected significantly by the vent processes; excessive amount of Hg was expected to be released via ventpipes penetrating up to 60 m depths of the deep landfilled waste layer. The influence of these vent source processes was reflected very sensitively by the windrose pattern. The data collected during the non-easterly winds were representing the typical pattern for a strong source area in which upward emission is predominant in both strength and frequency. On the other hand, the data collected from the easterly winds were characterized by excessive deposition of Hg which we suspect is due mostly to the nearest vent located easterly from our measurement spot. The unique characteristics of each data group, divided by windrose pattern, were consistent from apparent difference in: (1) the absolute magnitude of gradient/flux data sets, (2) frequency of exchange for each of two vertical directions, and (3) E/ D (emission/deposition) ratios for most relevant parameters. The analysis of the short-term variability of exchange patterns over a 24-h scale, also exhibited that the patterns for two different conditions were quite contrasting as a function of time. The magnitude of bidirectional fluxes in the present study is significantly high with values of 254±224 ( N=71 emissions out of 79 fluxes quantified during non-easterly winds) and -1164±1276 ng m -2 h -1 ( N=14 depositions out of 16 fluxes during easterly winds), respectively. If the computed emission rate is extrapolated, we estimate that annual emission of Hg from the study area can amount to approximately 6 kg which is comparable with the estimates for other areas around the globe under strong Hg-pollution.

Kim, Ki-Hyun; Kim, Min-Young; Lee, Gangwoong

395

Effects of probiotic administration on zebrafish development and reproduction.  

PubMed

As the consumption of probiotics increases worldwide, scientists focus on identifying bacterial strains able to improve human life quality and evidence the biological pathways affected by probiotic treatment. In this review, some recent observations on the effects of changes of microbiota on zebrafish metabolism were discussed. In addition, the effects of Lactobacillus rhamnosus - a component of the human gut microflora - as a diet supplement on Danio rerio were presented. When administered chronically, L. rhamnosus may affect larval development and the physiology of reproductive system in the zebrafish model. It was hypothesized exogenous L. rhamnosus accelerates larval growth and backbone development by acting on insulin-like growth factors-I (igfI) and -II (igfII), peroxisome proliferator activated receptors-? and -?, (ppar?,?) vitamin D receptor-? (vdr?) and retinoic acid receptor-? (rar?). Gonadal differentiation was anticipated at 6weeks together with a higher expression of gnrh3 at the larval stage when L. rhamnosus was administered throughout development. Moreover, brood stock alimented with a L. rhamnosus-supplemented diet showed better reproductive performances as per follicles development, ovulated oocytes quantification and embryos quality. A plausible involvement of factors such as leptin, and kiss1 and 2 in the improvements was concluded. The observations made on the physiology of female reproduction were correlated with the gene expression of a gigantic number of factors as the aromatase cytochrome p 19 (cyp19a), the vitellogenin (vtg) and the ? isoform of the E2 receptor (er?), luteinizing hormone receptor (lhr), 20-? hydroxysteroid dehydrogenase (20?-hsd), membrane progesterone receptors ? and ?, cyclin B, activin?A1, smad2, transforming growth factor ?1 (tgf?1), growth differentiation factor9 (gdf9) and bone morphogenetic protein15 (bmp15.) A model in which the exogenous L. rhamnosus in the digestive tract of zebrafish from the first days of life through sexual maturation positively influences the physiological performances of zebrafish was evidenced and a number of pathways that might be influenced by the presence of this human probiotic strain were proposed. PMID:23500006

Carnevali, O; Avella, M A; Gioacchini, G

2013-07-01

396

Episodic Geologic Evolution Of Mars  

NASA Astrophysics Data System (ADS)

After almost 4 years of operation in orbit, the High Resolution Stereo Camera (HRSC) Experiment on ESA's Mars Express Orbiter has covered almost 40% of the surface of Mars at a resolution of 10-20 m/pixel in color and stereo. By now, the international team of Co-Investigators has investigated much of the major structures appearing to have been shaped by volcanic, fluvial, glacial, or hydrothermal activity. Contrary to early Viking-based attempts of understanding the time-stratigraphic relationships on the martian surface by crater-counting techniques and principles of stratigraphic superposition, where most of the geological units and constructs came out as being rather old, in the range of billions of years, the new HRSC-based data tell us that Mars had continued activity throughout its whole history from more than 4 Ga ago until very recently, i.e. millions of years ago or in a few areas ongoing now. The new data, though, show episodic geological activity. There is a striking appearance of peaking of the geological activity or episodicity of resurfacing at certain times: approx. 3.5 Ga, 1 to 1.5 Ga, 300 to 600 m.y., approx. 200 m.y. ago, respectively. Even more striking is that within relatively narrow limits, the cratering ages of the different age groups fall together with the age groups of martian meteorites. The martian meteorite ages reflect both igneous events and aqueous alteration events. So do the cratering ages. There is a remarkable paucity of age occurrences in the 2-3 Ga age range in the cratering data. This corresponds to a paucity of meteorite ages in the same, even somewhat more extended age range. This appears to be a hint to either lower geologic activity in this time frame, or the covering up of more ancient activity by subsequent events <2 Ga ago, with the exception of the residues from the time >3 Ga ago (the peak at approx. 3.5 Ga) when the martian surface was thoroughly shaped at a very high level of activity by gigantic volcanic, fluvial, and glacial events which could not be completely erased by later events. The episodic behavior of martian geologic activity over time can possibly be explained by responses to the evolution of the interior of the planet that has just not reached plate tectonics. At the time of the peak of volcanic and fluvial activity around 3.7 to 3.3 Ga ago, Mars changed its environment from more basic to more acidic, and the large sulfate deposits formed. Then, rapidly, Mars fell dry on a global scale.

Neukum, G.; Co-Investigator Team

2007-12-01

397

New insights into the geologic evolution of Mars by the HRSC Experiment on the Mars Express Mission  

NASA Astrophysics Data System (ADS)

Abstract After 4 and a half years of operation in orbit, the High Resolution Stereo Camera (HRSC) Experiment on ESA's Mars Express Orbiter has covered more than 50% of the surface of Mars at a resolution of 10-20 m/pixel in color and stereo. By now, the international team of Co- Investigators has investigated much of the major structures appearing to have been shaped by volcanic, fluvial, glacial, or hydrothermal activity. Contrary to early Viking-based attempts of understanding the time-stratigraphic relationships on the martian surface by cratercounting techniques and principles of stratigraphic superposition, where most of the geological units and constructs came out as being rather old, in the range of billions of years, the new HRSC-based data tell us that Mars had continued activity throughout its whole history from more than 4 Ga ago until very recently. There is a striking appearance of peaking of the geological activity or episodicity of resurfacing at certain times: approx. 3.5 Ga, 1 to 1.5 Ga, 400 to 800 m.y., approx. 200 m.y. and around 100 m.y. ago, respectively. Even more striking is that within relatively narrow limits, the cratering ages of some of the different age groups fall together with the age groups of martian meteorites. The martian meteorite ages reflect both igneous events and aqueous alteration events. So do the cratering ages. There is a remarkable paucity of age occurrences in the 2-3 Ga age range in the cratering data. This corresponds to a paucity of meteorite ages in the same age range. This appears to be a hint to either lower geologic activity in this time frame, or the covering up of more ancient activity by subsequent events <2 Ga ago, with the exception of the residues from the time >3 Ga ago (the peak at approx. 3.5 Ga) when the martian surface was thoroughly shaped at a very high level of activity by gigantic volcanic, fluvial, glacial, and hydrothermal events which could not be completely erased by later events. The episodic behavior of martian geologic activity over time can possibly be explained by responses to the evolution of the interior of the planet that has just not reached plate tectonics. At the time of the peak of volcanic and fluvial activity around 3.7 to 3.5 Ga ago Mars changed its environment from more basic to more acidic conditions, and the large sulfate deposits formed. Then, rapidly, Mars fell dry on a global scale.

Neukum, G.

2008-09-01

398

New insights into the geologic evolution of Mars by the HRSC experiment on the Mars Express mission  

NASA Astrophysics Data System (ADS)

After 4 years of operation in orbit, the High Resolution Stereo Camera (HRSC) Experiment on ESA's Mars Express Orbiter has covered more than 40% of the surface of Mars at a resolution of 10-20 m/pixel in color and stereo. By now, the international team of Co-Investigators has investigated much of the major structures appearing to have been shaped by volcanic, fluvial, glacial, or hydrothermal activity. Contrary to early Viking-based attempts of understanding the time-stratigraphic relationships on the martian surface by crater-counting techniques and principles of stratigraphic superposition, where most of the geological units and constructs came out as being rather old, in the range of billions of years, the new HRSC-based data tell us that Mars had continued activity throughout its whole history from more than 4 Ga ago until very recently. There is a striking appearance of peaking of the geological activity or episodicity of resurfacing at certain times: approx. 3.5 Ga, 1 to 1.5 Ga, 300 to 600 m.y., approx. 200 m.y. ago, respectively. Even more striking is that within relatively narrow limits, the cratering ages of the different age groups fall together with the age groups of martian meteorites. The martian meteorite ages reflect both igneous events and aqueous alteration events. So do the cratering ages. There is a remarkable paucity of age occurrences in the 2-3 Ga age range in the cratering data. This corresponds to a paucity of meteorite ages in the same age range. This appears to be a hint to either lower geologic activity in this time frame, or, more likely, the covering up of more ancient activity by subsequent events <2 Ga ago, with the exception of the residues from the time >3 Ga ago (the peak at approx. 3.5 Ga) when the martian surface was thoroughly shaped at a very high level of activity by gigantic volcanic, fluvial, glacial, and hydrothermal events which could not be completely erased by later events. The episodic behavior of martian geologic activity over time can possibly be explained by responses to the evolution of the interior of the planet that has just not reached plate tectonics. At the time of the peak of volcanic and fluvial activity around 3.7 to 3.3 Ga ago Mars changed its environment from more basic to more acidic conditions, and the large sulfate deposits formed. Then, rapidly, Mars fell dry on a global scale.

Neukum, Gerhard

399

TYPE IIn SUPERNOVA SN 2010jl: OPTICAL OBSERVATIONS FOR OVER 500 DAYS AFTER EXPLOSION  

SciTech Connect

We present extensive optical observations of a Type IIn supernova (SN IIn) 2010jl for the first 1.5 years after its discovery. The UBVRI light curves demonstrated an interesting two-stage evolution during the nebular phase, which almost flatten out after about 90 days from the optical maximum. SN 2010jl has one of the highest intrinsic H{alpha} luminosities ever recorded for an SN IIn, especially at late phase, suggesting a strong interaction of SN ejecta with the dense circumstellar material (CSM) ejected by the progenitor. This is also indicated by the remarkably strong Balmer lines persisting in the optical spectra. One interesting spectral evolution about SN 2010jl is the appearance of asymmetry of the Balmer lines. These lines can be well decomposed into a narrow component and an intermediate-width component. The intermediate-width component showed a steady increase in both strength and blueshift with time until t {approx} 400 days after maximum, but it became less blueshifted at t {approx} 500 days, when the line profile appeared relatively symmetric again. Owing to the fact that a pure reddening effect will lead to a sudden decline of the light curves and a progressive blueshift of the spectral lines, we therefore propose that the asymmetric profiles of H lines seen in SN 2010jl are unlikely due to the extinction by newly formed dust inside the ejecta, contrary to the explanation by some early studies. Based on a simple CSM-interaction model, we speculate that the progenitor of SN 2010jl may suffer a gigantic mass loss ({approx}30-50 M{sub Sun }) a few decades before explosion. Considering a slow-moving stellar wind (e.g., {approx}28 km s{sup -1}) inferred for the preexisting, dense CSM shell and the extremely high mass-loss rate (1-2 M{sub Sun} yr{sup -1}), we suggest that the progenitor of SN 2010jl might have experienced a red supergiant stage and may explode finally as a post-red supergiant star with an initial mass above 30-40 M{sub Sun }.

Zhang Tianmeng; Wu Chao; Zhai Meng; Wu Hong; Fan Zhou; Zou Hu; Zhou Xu; Ma Jun [National Astronomical Observatories of China, Chinese Academy of Sciences, Beijing 100012 (China); Wang Xiaofeng; Chen Juncheng; Chen Jia; Liu Qin; Huang Fang; Liang Jide; Zhao Xulin [Physics Department and Tsinghua Center for Astrophysics (THCA), Tsinghua University, Beijing 100084 (China); Lin Lin [Center for Astrophysics, University of Science and Technology of China, No. 96, JinZhai Road Baohe District, Hefei, Anhui 230026 (China); Wang Min [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing, 210008 (China); Dennefeld, Michel [Institut d'Astrophysique de Paris, and University Pierre et Marie Curie (Paris 6) (France); Zhang Jujia, E-mail: armengjade@gmail.com, E-mail: wang_xf@mail.tsinghua.edu.cn [Yunnan Astronomical Observatory, Chinese Academy of Sciences, Kunming 650011 (China)

2012-11-01

400

Why is the Sun Active?  

NASA Astrophysics Data System (ADS)

This fundamental, centuries-old astrophysics question prompted G. E. Hale to create modern solar research. The question (of practical importance to humans) endures and motivates most solar work. What would we tell Hale about recent work if he reappeared among us? Great progress is being made in three areas, all of which he either initiated or strongly influenced. First, Hale would probably be surprised that we can now `look' at activity beneath the surface by studying the oscillations discovered in 1959 using the 60-foot tower telescope that he built in 1907. Such helioseismology research points to the interface between the differentially-rotating convection zone and the almost-uniformly-rotating radiative interior as the nursery of solar activity. Next, Hale's discovery of magnetic fields at the surface of the Sun has led to today's idea that magnetism is at the root of virtually all solar activity phenomena. His interest in vortical (or helical) patterns associated with magnetic fields has recently been reawakened and is now a vigorous area of solar research. The twist of a magnetic field may be almost as important as the field itself in producing violent solar activity. Finally, The study of the solar atmosphere against the solar disk, initiated in Chicago by Hale in 1891, has allowed us to observe the interactions of mass motions and magnetic fields that produce gigantic explosions such as solar flares and coronal mass ejections. These observations strongly suggest that magnetic reconnection is a fundamental and nearly ubiquitous process associated with the activity of the solar atmosphere. Hale vigorously promoted simultaneous advances in observation and theory. Today, a detailed answer to the title of this talk is probably in the literature, but we lack adequate observational tools to test the many published theories and ideas. Hale made revolutionary breakthroughs by applying the latest technology to make new observations that were stimulated by theory and conjecture. We are in a position to apply modern technology, as Hale did a century ago, to make breakthrough observations again. Two exciting next-millennium examples, in the tradition of Hale, are the use of space to get steady, sub-arc-second image quality (the Solar-B mission), and a large-aperture, adaptive-optics-equipped, ground-based telescope for detailed studies of solar MHD phenomena (the Advanced Solar Telescope).

Harvey, J.

1999-05-01

401

Maximum Earthquake Magnitude Assessments by Japanese Government Committees (Invited)  

NASA Astrophysics Data System (ADS)

The 2011 Tohoku earthquake (M 9.0) was the largest earthquake in Japanese history and such a gigantic earthquake was not foreseen around Japan. After the 2011 disaster, various government committees in Japan have discussed and assessed the maximum credible earthquake size around Japan, but their values vary without definite consensus. I will review them with earthquakes along the Nankai Trough as an example. The Central Disaster Management Council, under Cabinet Office, set up a policy for the future tsunami disaster mitigation. The possible future tsunamis are classified into two levels: L1 and L2. The L2 tsunamis are the largest possible tsunamis with low frequency of occurrence, for which saving people's lives is the first priority with soft measures such as tsunami hazard maps, evacuation facilities or disaster education. The L1 tsunamis are expected to occur more frequently, typically once in a few decades, for which hard countermeasures such as breakwater must be prepared. The assessments of L1 and L2 events are left to local governments. The CDMC also assigned M 9.1 as the maximum size of earthquake along the Nankai trough, then computed the ground shaking and tsunami inundation for several scenario earthquakes. The estimated loss is about ten times the 2011 disaster, with maximum casualties of 320,000 and economic loss of 2 trillion dollars. The Headquarters of Earthquake Research Promotion, under MEXT, was set up after the 1995 Kobe earthquake and has made long-term forecast of large earthquakes and published national seismic hazard maps. The future probability of earthquake occurrence, for example in the next 30 years, was calculated from the past data of large earthquakes, on the basis of characteristic earthquake model. The HERP recently revised the long-term forecast of Naknai trough earthquake; while the 30 year probability (60 - 70 %) is similar to the previous estimate, they noted the size can be M 8 to 9, considering the variability of past earthquakes. The Nuclear Regulation Authority, established in 2012, makes independent decisions based on the latest scientific knowledge. They assigned maximum credible earthquake magnitude of 9.6 for Nankai an Ryukyu troughs, 9.6 for Kuirl-Japan trench, and 9.2 for Izu-Bonin trench.

Satake, K.

2013-12-01

402

Electronic-Theater 2001: Visions of Our Planet's Atmosphere, Land and Oceans  

NASA Technical Reports Server (NTRS)

The NASA/NOAA/AMS Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to Wisconsin, Madison and the Monona Terrace Center. Drop in on the Kennedy Space Center and Park City Utah, site of the 2002 Olympics using I m IKONOS "Spy Satellite" data. Go back to the early weather satellite images from the 1960s pioneered by UW. Scientists and see them contrasted with the latest US and International global satellite weather movies including hurricanes & tornadoes. See the latest spectacular images from NASA/NOAA remote sensing missions like Terra GOES, TRMM, SeaWiFS, Landsat 7 that are visualized & 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 Newsweek, TIME, National Geographic, Popular Science covers & National & International Network TV. New visualization tools allow us to roam & zoom through massive global images eg Landsat tours of the US, Africa, & New Zealand 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 massive dust storms sweeping across Africa. See vortices and currents in the global oceans that bring up the nutrients to feed tiny plankton and draw the fish, whales and fisherman. See the how the ocean blooms in response to these currents and El Nina/La Nina climate changes. The demonstration is interactively driven by a SGI Onyx 11 Graphics Supercomputer with four CPUs, 8 Gigabytes of RAM and Terabyte of disk. With five projectors on a giant IMAX sized 18 x 72 ft screen. See the city lights, fishing fleets, gas flares and bio-mass burning of the Earth at night observed by the "nightvision" DMSP military satellite.

Hasler, Authur; Starr, David OC. (Technical Monitor)

2001-01-01

403

Sprite-producing Convective Storms within the Colorado Lightning Mapping Array  

NASA Astrophysics Data System (ADS)

The multi-year, multi-institution effort entitled Physical Origins of Coupling to the Upper Atmosphere from Lightning (PhOCAL), has among its goals to qualitatively understand the meteorology and lightning flash characteristics that produce the unusual and/or very energetic lightning responsible for phenomena such as sprites, halos, elves, blue jets and gigantic jets, collectively known as Transient Luminous Events (TLEs). A key task is to obtain simultaneous video, ideally with a high-speed imager (HSI), of both a TLE and its parent lightning discharge, within the domain of a 3-D Lightning Mapping Array (LMA). While conceptually simple, this task is logistically quite complicated. In 2012, a new 15-station Colorado LMA (COLMA) became operational, covering northeastern Colorado, with the Yucca Ridge Field Station (YRFS) near its western edge. The National Charge Moment Change Network (CMCN), which since 2007 has been documenting sprite-class +CGs (those with impulse change moment changes >100 C km), indicates that a strong gradient of energetic +CGs exists west-to-east through the COLMA, with the most likely region for sprite-producing storms being in the COLMA eastern fringes (western Kansas and Nebraska). Yet, on 8 and 25 June, 2012, intense convective systems formed in the COLMA along and just east of the Front Range, producing severe weather and intense lightning. On the 8th, four sprite parent +CGs were captured at 3000 fps from YRFS with the sprites confirmed by dual (conventional speed) cameras in New Mexico. In a second storm on the 25th, viewing conditions prevented +CG video acquisition, but sprites were logged over the COLMA and detailed reconstructions of the discharges are being made. The parent discharges often began as upward negative leaders propagating into a mid-level positive charge layer at 8-10 km. They often originated within or near the convective core before expanding outward into a stratiform region and involving several hundred square kilometers, to be followed by +CG and strong continuing currents. LMA indications of recoil leaders appear confirmed by some high-speed video. These storms were somewhat smaller than the typical sprite-bearing MCS. The storm structures will be categorized using GOES IR, NEXRAD reflectivity, NLDN lightning data, CMCN impulse charge moment data, and full charge moment charge retrievals. The sprite parent CG discharges will be cataloged along with their points of origin, the height and volume from which charge is removed, the charge lowered to ground, and the continuing current characteristics. These CGs will be placed in the context of the storms' meteorological structure and evolution.

Lyons, W. A.; Cummer, S. A.; Rison, W.; Krehbiel, P. R.; Lang, T. J.; Rutledge, S. A.; Lu, G.; Stanley, M. A.; Ashcraft, T.; Nelson, T. E.

2012-12-01

404

Gravity and magnetic anomalies of the western Arctic ocean and its margins provide an imperfect window to a complex, multi-stage tectonic history (Invited)  

NASA Astrophysics Data System (ADS)

Numerous scenarios are still in play for the tectonic development of the western Arctic. A wide range of kinematic models have been proposed for the opening of the Canadian basin. These models feature different combinations and geometries of extensional and transform motion and have informal descriptive names including the so-called ‘windshield wiper’, ‘railroad tracks’, ‘squeegee’, and ‘saloon door’ options. Another controversial issue is the timing and role of the gigantic Alpha-Mendeleev large igneous province relative to the tectonic stages. In our opinion, many current Arctic models have not adequately dealt with the mass and thermal fluxes implied by this huge province. Available data are extremely sparse for the circum-Arctic, although current political and economic interests are fueling accelerated data collection. Recent compilations of gravity and magnetic data are currently the best bets for synoptic imaging, however imprecise, of crustal composition and structure. Modeling and interpretation of regional geophysical anomalies provide some of the only available tests for scenario evaluation in the absence of more direct determinations of crustal structure and composition. Our goal in this talk is to review the key geophysical features of the western Arctic and relate these elements to the expectations of competing tectonic models. These key geophysical features include (1) contrasting Arctic domains of overall magnetic “thickness” and anomaly “fabric” (the domains correlate generally with broad tectonic categories); (2) cryptic sub-linear magnetic anomalies in the Canada basin (interpreted by some authors to be oceanic stripes); (3) a subtle but persistent gravity trough in the central Canada basin (inferred by some authors to represent an extensional trough); (4) spectacular “shelf edge” free-air gravity anomalies along the Canadian and Alaskan passive margins that show significant along-strike variation (which can be interpreted to reflect relative amount of magmatic activity); (5) complex and chaotic magnetic texture and fabric in the Alpha-Mendeleev large igneous province (perhaps reflecting pre-intrusive structural features and trends); and (6) large-amplitude, long-wavelength “deep magnetic highs” including well-studied examples in northern Alaska and north-western Canada (inferred to represent deep crustal elements that influence overall strength of the crust/upper mantle). The overall complexity of the Arctic geophysical anomaly fabric is indicative of significant variation in crustal composition and reflects a complicated, multi-stage tectonic development. It seems very likely that the best tectonic solutions for the circum-Arctic will include sub-elements of many current end-member models.

Saltus, R. W.; Miller, E. L.; Gaina, C.

2010-12-01

405

The Italian drilling project of the Mont Blanc road tunnel in the late fifties: an example of no geological care and lack of ethics in carrying out a big work.  

NASA Astrophysics Data System (ADS)

In the first decade after the Second World War Italy was rushing to recover a positive role among European countries; basic needs as road communications with European neighbours became main priorities. The necessity of a rapid connection with South-eastern France, a subject already debated between the two nations over more than 50 years, appeared then on first line; the two countries convened on a joint investment for the construction of a tunnel across the international border of Mont Blanc, along the shortest track between Courmayeur and Chamonix. The political agreements were in favour of the quickest start of the drilling operations and such obligation imposed on the Italian side an impoverishment of the project content, specially concerning geological issues. No surveys were performed on fracture systems, cataclastic zones and faults, on the few rock ridges standing above the tunnel line and outcropping through thick talus cones, moraines, ice tongues and their related ice plateaus. Metasediments, migmatites and poorly foliated granites were to be drilled. Three Italian academics were allowed by the drilling company to track the working progress and collect rocks for comparison with other Alpine types; they mapped the lithology and the fault zonesall along the freshly excavated tunnel; the results of such survey appeared after the end of works. Geologists from Florence University published the surface granite faulting pattern 20 years after the road tunnel became operative. Such geological cares could have located the risky zones in time for the tunnel project, mitigating the catastrophic effects of sudden drainage of subglacial water from the Vallée Blanche ice plateau (Ghiacciaio del Gigante) at progression 3800m, that caused dramatic accidents and affected negatively the economy of the drilling. Also the wallrock temperature drops, measured during the drill, should have warned the company management on the location of dangerous fracture zones. Anxiety of national renaissance probably committed the Italian team to a fast conclusion, skipping attention from geological urgencies. But did attitudes change since then? This late episode gives us the opportunity to reflect on the necessity of making politicians seriously aware of the importance of geology when carrying out big works, to impose by law more effective policies and make interrelations between the involved professionals mandatory. Firm geoethic principles should guide choices and decisions in projects of great environmental impact.

Gosso, Guido; Croce, Giuseppe; Matteucci, Ruggero; Peppoloni, Silvia; Piacente, Sandra; Wasowski, Janusz

2013-04-01

406

Genesis and formation oil and gas fields (Azerbaijan)  

NASA Astrophysics Data System (ADS)

The large amount of material of HC isotope composition of over 330 samples allow to restore the history of oil and gas deposits formation within the South-Caspian Depression. Maps of isotope composition changes according to area extent, as well as graphs of HC distribution depending upon stratigraphic age, including rocks, graphs of isotope composition change on sampling depth were compiled for HC study and oil-gas deposits formation. Comparison of mud volcanoes gases, oil and gas fields, gas-hydrates and bottom sediments were conducted. Gases genesis according to M. Shoelle and A. James methodic were studied. Model of area paleoconstruction was studied. Two stages of formation were distinguished as a result of gases study of various forms of their manifestation (gases of mud volcanoes, oil and gas fields, gas hydrate, bottom sediments) as well as isotope gases composition distribution in area of extent including stratigraphic age of deposits, depth of sampling and application of M. Shoelle and A. James. There were determined basic ways of HC migration as well as estimated oil-gas content prospective. The first stage has begun in the underlying PS deposits and continued up to PS deposits. At this stage one various kind of tectonic fluctuations can observed. The second stage of HC formation has started from PS and characterised with a change of geodynamic conditions in region. Avalanche sedimentation, predominance of descending movements over ascending ones promoted the accumulation of thick sediments in PS age. As a result of sediments accumulation and tectonic processes (down warping) in the deep-seated basin led to the complication of thermobaric conditions in the sedimentary series. The studied chemical and HC gases isotope composition showed that basic source of oil and gas formation is located in the deep areas of central and near-flank parts of depression. HC migration has mainly occurred upward. Study of HC migration trend in time and area as well as areas of generation etc. allows to reveal some structures where there is evidence of HC accumulation with large and gigantic reserves.

Poletayev, Alexander

2010-05-01

407

Europe's battery: The making of the Alpine energy landscape, 1870-1955  

NASA Astrophysics Data System (ADS)

This study examines the environmental history of hydropower development in the Alps from the mid-nineteenth to the mid-twentieth centuries. Analyzing government archival files, associational journals, conference proceedings, and published contemporary material from several Alpine countries, it seeks to determine how and why Europeans modified the Alpine landscape to generate hydropower, and to explore the consequences of these decisions. I argue that during this time period, Europeans thoroughly transformed the Alpine environment, creating what I call "Europe's Battery": a gigantic system for storing hydropower and distributing it on a continental scale. This study shows how nineteenth-century innovations in energy technology contributed to a dramatic shift in the perception of the Alps as a landscape of "white coal." It demonstrates how at the outset of electrification, Europeans modified Alpine waterways on an unprecedented scale in order to tap into the power of flowing Alpine water. I show how after the turn of the twentieth century, Europeans took advantage of the unique mountain environment to store water, first by converting existing lakes into reservoirs. The practice countered what was perceived to be the greatest disadvantage of white coal: its climate-influenced inconstancy. This study shows the importance of war, and especially the First World War, in the forging of the new Alpine landscape. Finally, this study illustrates how from the interwar period to the aftermath of the Second World War, Europeans put the finishing touches on the new Alpine energy landscape by creating large reservoirs behind dams and feeding Alpine hydroelectricity into a burgeoning European electricity grid. By 1955 the Alps had become one of the most important energy landscapes in Europe. This history of the Alpine energy landscape contributes to a number of historiographical fields. It represents an important chapter in the environmental history of one of the world's most iconic landscapes. It sheds light on the hydroelectric energy transition and shows the environmental impacts of electrification. Finally the history of Europe's Battery illuminates an alternative regional history of energy development and industrialization in Europe, one based on water and electricity and not coal.

Landry, Marc D., II

408

Power scaling of resonantly pumped Yb-free Er-doped fiber laser  

NASA Astrophysics Data System (ADS)

Even though Yb-doped fiber lasers are known to be the most powerful and most efficient among all fiber lasers, recent successes in the eye-safe ~1.5?m Yb-Er-doped fiber lasers (where Er is excited through Yb-Er energy transfer) are quite impressive. Output power of Yb-Er fiber lasers reached ~300 W level and their optical-to-optical efficiency, for somewhat lower power levels, is exceeding 40% [2]. Nevertheless, as far as real eye safety is concerned, multi-hundred Watt Yb-Er fiber lasers typically carry in their output a significant fraction of competing 1-?m Yb emission, which totally compromises an eye-safe side of the application. Ultimate efficiency and thermal management of Yb-Er approach are also suffering due to: (i), inefficiency of Yb-Er energy transfer and, (ii), gigantic ~40% quantum defect of Er-doped fiber pumped at 9XX-nm. Presented here are very recent and successful results on power scaling of resonantly pumped Yb-free Er-doped fiber lasers and amplifiers. We are reporting an Ybfree Er-doped cladding-pumped fiber power scaling to ~50 W with ~57% optical-tooptical efficiency [6] in a few first experimental steps. This is clear manifestation of scaling potential of this most efficient approach to high power eye-safe fiber laser. The only competing approach to scalable eye-safe fiber laser implements Tm3+-doped fibers pumped at ~790 nm while relying on well known "2-for-1" process leading to quite efficient excitation of the ~2?m Tm3+ laser operation [4]. This approach has operational optical-to-optical efficiency quantum limit of ~75% [4], while resonantly pumped Ybfree Er-doped fiber laser's optical-to-optical efficiency quantum limit exceeds 95% due to its low-quantum-defect (QD) pump-lase scheme. Significant scaling potential of resonantly-pumped Yb-free Er-doped fiber lasers and amplifiers sets a path to an eye-safe fiber laser concept with drastically relaxed thermal management and nearly diffraction limited beam quality at ~kW-=-class power levels as well as high electrical to optical efficiency.

Dubinskii, M.; Zhang, J.; Ter-Mikirtychev, V.

2009-05-01

409

Leveraging the International Polar Year Legacy: Providing Historical Perspective for IPY Education, Outreach and Communication Efforts  

NASA Astrophysics Data System (ADS)

As the International Polar Year 2007-2008 (IPY) is fast approaching, it is important to look back and learn from the previous experience. Over 125 years ago, when an Austrian explorer and naval officer Lt. Karl Weyprecht called for an international yearlong intensive effort to study the Polar Regions, he probably never imagined that his model for international collaboration would become so widely popular. Frustrated by the lack of coordinated, international collaboration in research activities, Weyprecht proposed an intensive burst of research activity over the course of at least a year. The first IPY began in 1882 with 12 nations establishing 13 stations in the Arctic and 2 in the Southern Hemisphere. The initial yearlong plan did not go beyond data collection. However, the idea lived in the minds of scientists worldwide and the second IPY followed the first one 50 years later. By 1932, technology evolved significantly, and on top of ground-based meteorological and geophysical measurements, data collection also included radiosonde and acoustic atmospheric measurements. Occurring during a global economic depression, and between world wars, the second IPY faced many challenges. However, 40 permanent stations were established, some of which are still active. Scientific exploration also reached remote frontiers from Antarctica to the Earth's ionosphere. Less than a decade after the WWII, the idea of the next IPY started to circulate in scientific circles. The world was focused on space exploration and the word "polar" seemed too narrow for the gigantic projects planned for the 1957. That is why the initial idea of the third IPY evolved into the International Geophysical Year (IGY), although polar regions were still a major focus. The success of the IGY is almost overwhelming the first Earth orbiting satellites, a traverse of Antarctica, a discovery of the Radiation Belt, a series of science education films about IGY activities and research themes are just a few examples. In addition to the scientific breakthroughs, the IGY was an extremely successful political event. In the middle of the Cold War, scientists from competing countries had a unique chance to meet and share their research ideas. This peaceful collaboration resulted in 1961 signing of the Antarctic Treaty, protecting the sixth continent for scientific, non-military research. Many AGU scientists indicate that the IGY educational programs, along with the rapid development of science and technology following the IGY inspired their career choice.

Tsukernik, M.; McCaffrey, M. S.

2006-12-01

410

Optical Rogue Waves: Theory and Experiments  

NASA Astrophysics Data System (ADS)

In the ocean, giant waves (also called killer waves, freak or rogue waves) are extremely rare and strong events. They are not well understood yet and the conditions which favour their emergence are unclear. Very recently, it was shown that the governing equations [1] as well as the statistical properties of an optical pulse propagating inside an optical fibre [2] mimic very well these gigantic surface waves in the ocean. Here we generate both experimentally and numerically optical rogue waves in a photonic crystal fiber (microstructured fiber) with continuous wave (CW) pumps. This is relevant for establishing an analogy with rogue waves in an open ocean. After recalling fundamental rogue waves [3] known as Akhmediev breathers that are solutions of pure nonlinear Schrödinger (NLS) equation, we analytically demonstrate that a generalized NLS equation, which governs the propagation of light in the fiber, exhibits convective modulationnal instability [4]. The latter provides one of the main explanations of the optical rogue wave extreme sensitivity to noisy initial conditions at the linear stage of their formation [5]. In the highly nonlinear regime, we provide the evidence that optical rogue waves result from soliton collisions leading to the rapid appearance/disappearance of a powerful optical pulse [6]. REFERENCES [1] C. Kharif, E. Pelinovsky, and A. Slunyaev, "Rogue Waves in the ocean", Springer Berlin Heidelberg, 2009 [2] D. R. Solli, C. Ropers, P. Koonath, and B. Jalali, "Optical rogue waves" Nature 450, 1054-1058, (2008). [3] N. Akhmediev, A. Ankiewicz, and M. Taki, "Waves that appear from nowhere and disappear without a trace", Phys. Lett. A 373, 675 (2009). [4] A. Mussot, E. Louvergneaux, N. Akhmediev, F. Reynaud, Delage, and M. Taki, "Optical fiber systems are convectively unstable", Phys. Rev. Lett. 101, 113904 (2008). [5] M. Taki, A. Mussot, A. Kudlinski, E. Louvergneaux, M. Kolobov, M. Douay, "Third-order dispersion for generating optical rogue solitons", Phys. Lett. A 374, 691-695 (2010). [6] A. Mussot, A. Kudlinski, M. Kolobov, E. Louvergneaux, M. Douay and M. Taki, "Observation of extreme temporal events in CW-pumped supercontinuum", Opt. Express 17 (19), 17010 (2009).

Taki, M.; Mussot, A.; Kudlinski, A.; Louvergneaux, E.; Kolobov, M.

2010-05-01

411

Animal Tails  

NSDL National Science Digital Library

Call it tail envy. With only a vestigial nub to show for ourselves, perhaps it's no wonder that animal tails capture our attention. The following Web sites present some of the more interesting tails to be found in the animal kingdom. The first Web site contains a recent article from Discovery News describing new findings that at least one species of scorpion produces two distinct types of tail venom, which have completely different effects on their victims (1). The next site from Singapore Zoological Gardens introduces the cebids (our New World monkey cousins), some of which have amazing prehensile tails that are used like a fifth limb (2). The rattlesnake is another famously-tailed creature, highlighted in the following site from the Arizona-Sonora Desert Museum (3). The site covers the main aspects of rattlesnake natural history, including a section on how the rattle forms. The Great Plains Nature Center in Wichita, Kansas, offers a Web page devoted to the beaver, including tail trivia and an audio clip of a resident beaver surprised in his den at the Kansas Wildlife Exhibit (4). Anyone who has witnessed the freakishly fascinating spectacle of a gecko leaving its tail behind to distract a would-be predator will appreciate this brief bio of the Tokay gecko, presented by ReptileCenter.com, the Herpetologist's Portal (5). Stacy's Wag'N'Train -- offering dog-training classes in San Jose, California -- provides this online guide to dog body language, which would have a very limited vocabulary without the tail (6). So, how did the peacock get its tail? It's a simple question that has driven zoologists crazy for over a century. The next Web site (7) contains an in-depth article on the subject from the Independent (London), offered through National Geographic News. And finally, the bizarre gulper eel -- able to tie its tail in several knots -- gets is own Web page on Pangea, the Web server for the Department of Educational Leadership and Technology at Southeastern Louisiana University (8). This deep-sea curiosity uses its bioluminescent tail tip to lure hapless prey into its impossibly gigantic mouth.

Sohmer, Rachel.

2003-01-01

412

Sharpest views of Betelgeuse reveal how supergiant stars lose mass-Unveiling the true face of a behemoth  

NASA Astrophysics Data System (ADS)

Using different state-of-the-art techniques on ESO's Very Large Telescope, two independent teams of astronomers have obtained the sharpest ever views of the supergiant star Betelgeuse. They show that the star has a vast plume of gas almost as large as our Solar System and a gigantic bubble boiling on its surface. These discoveries provide important clues to help explain how these mammoths shed material at such a tremendous rate. Betelgeuse - the second brightest star in the constellation of Orion (the Hunter) - is a red supergiant, one of the biggest stars known, and almost 1000 times larger than our Sun [1]. It is also one of the most luminous stars known, emitting more light than 100000 Suns. Such extreme properties foretell the demise of a short-lived stellar king. With an age of only a few million years, Betelgeuse is already nearing the end of its life and is soon doomed to explode as a supernova. When it does, the supernova should be seen easily from Earth, even in broad daylight. Red supergiants still hold several unsolved mysteries. One of them is just how these behemoths shed such tremendous quantities of material - about the mass of the Sun - in only 10 000 years. Two teams of astronomers have used ESO's Very Large Telescope (VLT) and the most advanced technologies to take a closer look at the gigantic star. Their combined work suggests that an answer to the long-open mass-loss question may well be at hand. The first team used the adaptive optics instrument, NACO, combined with a so-called "lucky imaging" technique, to obtain the sharpest ever image of Betelgeuse, even with Earth's turbulent, image-distorting atmosphere in the way. With lucky imaging, only the very sharpest exposures are chosen and then combined to form an image much sharper than a single, longer exposure would be. The resulting NACO images almost reach the theoretical limit of sharpness attainable for an 8-metre telescope. The resolution is as fine as 37 milliarcseconds, which is roughly the size of a tennis ball on the International Space Station (ISS), as seen from the ground. "Thanks to these outstanding images, we have detected a large plume of gas extending into space from the surface of Betelgeuse," says Pierre Kervella from the Paris Observatory, who led the team. The plume extends to at least six times the diameter of the star, corresponding to the distance between the Sun and Neptune. "This is a clear indication that the whole outer shell of the star is not shedding matter evenly in all directions," adds Kervella. Two mechanisms could explain this asymmetry. One assumes that the mass loss occurs above the polar caps of the giant star, possibly because of its rotation. The other possibility is that such a plume is generated above large-scale gas motions inside the star, known as convection - similar to the circulation of water heated in a pot. To arrive at a solution, astronomers needed to probe the behemoth in still finer detail. To do this Keiichi Ohnaka from the Max Planck Institute for Radio Astronomy in Bonn, Germany, and his colleagues used interferometry. With the AMBER instrument on ESO's Very Large Telescope Interferometer, which combines the light from three 1.8-metre Auxiliary Telescopes of the VLT, the astronomers obtained observations as sharp as those of a giant, virtual 48-metre telescope. With such superb resolution, the astronomers were able to detect indirectly details four times finer still than the amazing NACO images had already allowed (in other words, the size of a marble on the ISS, as seen from the ground). "Our AMBER observations are the sharpest observations of any kind ever made of Betelgeuse. Moreover, we detected how the gas is moving in different areas of Betelgeuse's surface ? the first time this has been done for a star other than the Sun", says Ohnaka. The AMBER observations revealed that the gas in Betelgeuse's atmosphere is moving vigorously up and down, and that these bubbles are as large as the supergiant star itself. Their unrivalled observations have led

2009-07-01

413

Methods of Mathematical and Computational Physics for Industry, Science, and Technology  

NASA Astrophysics Data System (ADS)

Many industrial problems provide scientists with important and challenging problems that need to be solved today rather than tomorrow. The key role of mathematical physics, modelling, and computational methodologies in addressing such problems continues to increase. Science has never been exogenous to applied research. Gigantic ships and steam engines, repeating catapult of Dionysius and the Antikythera `computer' invented around 80BC are just a few examples demonstrating a profound link between theoretical and applied science in the ancient world. Nowadays, many industrial problems are typically approached by groups of researchers who are working as a team bringing their expertise to the success of the entire enterprise. Since the late 1960s several groups of European mathematicians and scientists have started organizing regular meetings, seeking new challenges from industry and contributing to the solution of important industri