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Sample records for rico transoceanic dispersal

  1. Tsunami-driven rafting: Transoceanic species dispersal and implications for marine biogeography.

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    Carlton, James T; Chapman, John W; Geller, Jonathan B; Miller, Jessica A; Carlton, Deborah A; McCuller, Megan I; Treneman, Nancy C; Steves, Brian P; Ruiz, Gregory M

    2017-09-29

    The 2011 East Japan earthquake generated a massive tsunami that launched an extraordinary transoceanic biological rafting event with no known historical precedent. We document 289 living Japanese coastal marine species from 16 phyla transported over 6 years on objects that traveled thousands of kilometers across the Pacific Ocean to the shores of North America and Hawai'i. Most of this dispersal occurred on nonbiodegradable objects, resulting in the longest documented transoceanic survival and dispersal of coastal species by rafting. Expanding shoreline infrastructure has increased global sources of plastic materials available for biotic colonization and also interacts with climate change-induced storms of increasing severity to eject debris into the oceans. In turn, increased ocean rafting may intensify species invasions. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  2. Radiation and repeated transoceanic dispersal of Schoeneae (Cyperaceae) through the southern hemisphere.

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    Viljoen, Jan-Adriaan; Muasya, A Muthama; Barrett, Russell L; Bruhl, Jeremy J; Gibbs, Adele K; Slingsby, Jasper A; Wilson, Karen L; Verboom, G Anthony

    2013-12-01

    The broad austral distribution of Schoeneae is almost certainly a product of long-distance dispersal. Owing to the inadequacies of existing phylogenetic data and a lack of rigorous biogeographic analysis, relationships within the tribe remain poorly resolved and its pattern of radiation and dispersal uncertain. We employed an expanded sampling of taxa and markers and a rigorous analytic approach to address these limitations. We evaluated the roles of geography and ecology in stimulating the initial radiation of the group and its subsequent dispersal across the southern hemisphere. A dated tree was reconstructed using reversible-jump Markov chain Monte Carlo (MCMC) with a polytomy prior and molecular dating, applied to data from two nuclear and three cpDNA regions. Ancestral areas and habitats were inferred using dispersal-extinction-cladogenesis models. Schoeneae originated in Australia in the Paleocene. The existence of a "hard" polytomy at the base of the clade reflects the rapid divergence of six principal lineages ca. 50 Ma, within Australia. From this ancestral area, Schoeneae have traversed the austral oceans with remarkable frequency, a total of 29 distinct dispersal events being reported here. Dispersal rates between landmasses are not explicable in terms of the geographical distances separating them. Transoceanic dispersal generally involved habitat stasis. Although the role of dispersal in explaining global distribution patterns is now widely accepted, the apparent ease with which such dispersal may occur has perhaps been under-appreciated. In Schoeneae, transoceanic dispersal has been remarkably frequent, with ecological opportunity, rather than geography, being most important in dictating dispersal patterns.

  3. Transoceanic Dispersal and Plate Tectonics Shaped Global Cockroach Distributions: Evidence from Mitochondrial Phylogenomics.

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    Bourguignon, Thomas; Tang, Qian; Ho, Simon Y W; Juna, Frantisek; Wang, Zongqing; Arab, Daej A; Cameron, Stephen L; Walker, James; Rentz, David; Evans, Theodore A; Lo, Nathan

    2017-04-01

    Following the acceptance of plate tectonics theory in the latter half of the 20th century, vicariance became the dominant explanation for the distributions of many plant and animal groups. In recent years, however, molecular-clock analyses have challenged a number of well-accepted hypotheses of vicariance. As a widespread group of insects with a fossil record dating back 300 My, cockroaches provide an ideal model for testing hypotheses of vicariance through plate tectonics versus transoceanic dispersal. However, their evolutionary history remains poorly understood, in part due to unresolved relationships among the nine recognized families. Here, we present a phylogenetic estimate of all extant cockroach families, as well as a timescale for their evolution, based on the complete mitochondrial genomes of 119 cockroach species. Divergence dating analyses indicated that the last common ancestor of all extant cockroaches appeared ∼235 Ma, ∼95 My prior to the appearance of fossils that can be assigned to extant families, and before the breakup of Pangaea began. We reconstructed the geographic ranges of ancestral cockroaches and found tentative support for vicariance through plate tectonics within and between several major lineages. We also found evidence of transoceanic dispersal in lineages found across the Australian, Indo-Malayan, African, and Madagascan regions. Our analyses provide evidence that both vicariance and dispersal have played important roles in shaping the distribution and diversity of these insects.

  4. Global biogeography of scaly tree ferns (Cyatheaceae): evidence for Gondwanan vicariance and limited transoceanic dispersal.

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    Korall, Petra; Pryer, Kathleen M

    2014-02-01

    Scaly tree ferns, Cyatheaceae, are a well-supported group of mostly tree-forming ferns found throughout the tropics, the subtropics and the south-temperate zone. Fossil evidence shows that the lineage originated in the Late Jurassic period. We reconstructed large-scale historical biogeographical patterns of Cyatheaceae and tested the hypothesis that some of the observed distribution patterns are in fact compatible, in time and space, with a vicariance scenario related to the break-up of Gondwana. Tropics, subtropics and south-temperate areas of the world. The historical biogeography of Cyatheaceae was analysed in a maximum likelihood framework using Lagrange. The 78 ingroup taxa are representative of the geographical distribution of the entire family. The phylogenies that served as a basis for the analyses were obtained by Bayesian inference analyses of mainly previously published DNA sequence data using MrBayes. Lineage divergence dates were estimated in a Bayesian Markov chain Monte Carlo framework using beast. Cyatheaceae originated in the Late Jurassic in either South America or Australasia. Following a range expansion, the ancestral distribution of the marginate-scaled clade included both these areas, whereas Sphaeropteris is reconstructed as having its origin only in Australasia. Within the marginate-scaled clade, reconstructions of early divergences are hampered by the unresolved relationships among the Alsophila , Cyathea and Gymnosphaera lineages. Nevertheless, it is clear that the occurrence of the Cyathea and Sphaeropteris lineages in South America may be related to vicariance, whereas transoceanic dispersal needs to be inferred for the range shifts seen in Alsophila and Gymnosphaera . The evolutionary history of Cyatheaceae involves both Gondwanan vicariance scenarios as well as long-distance dispersal events. The number of transoceanic dispersals reconstructed for the family is rather few when compared with other fern lineages. We suggest that a causal

  5. Multilocus Phylogeny of the Afrotropical Freshwater Crab Fauna Reveals Historical Drainage Connectivity and Transoceanic Dispersal Since the Eocene.

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    Daniels, Savel R; Phiri, Ethel E; Klaus, Sebastian; Albrecht, Christian; Cumberlidge, Neil

    2015-07-01

    Phylogenetic reconstruction, divergence time estimations and ancestral range estimation were undertaken for 66% of the Afrotropical freshwater crab fauna (Potamonautidae) based on four partial DNA loci (12S rRNA, 16S rRNA, cytochrome oxidase one [COI], and histone 3). The present study represents the most comprehensive taxonomic sampling of any freshwater crab family globally, and explores the impact of paleodrainage interconnectivity on cladogenesis among freshwater crabs. Phylogenetic analyses of the total evidence data using maximum-likelihood (ML), maximum parsimony (MP), and Bayesian inference (BI) produced a robust statistically well-supported tree topology that reaffirmed the monophyly of the Afrotropical freshwater crab fauna. The estimated divergence times suggest that the Afrotropical Potamonautidae diverged during the Eocene. Cladogenesis within and among several genera occurred predominantly during the Miocene, which was associated with major tectonic and climatic ameliorations throughout the region. Paleodrainage connectivity was observed with specimens from the Nilo-Sudan and East African coast proving to be sister to specimens from the Upper Guinea Forests in West Africa. In addition, we observed strong sister taxon affinity between specimens from East Africa and the Congo basin, including specimens from Lake Tanganyika, while the southern African fauna was retrieved as sister to the Angolan taxa. Within the East African clade we observed two independent transoceanic dispersal events, one to the Seychelles Archipelago and a second to Madagascar, while we observe a single transoceanic dispersal event from West Africa to São Tomé. The ancestral area estimation suggested a West African/East African ancestral range for the family with multiple dispersal events between southern Africa and East Africa, and between East Africa and Central Africa The taxonomic implications of our results are discussed in light of the widespread paraphyly evident among a

  6. Phylogeographic Structure in Penguin Ticks across an Ocean Basin Indicates Allopatric Divergence and Rare Trans-Oceanic Dispersal.

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    Moon, Katherine L; Banks, Sam C; Fraser, Ceridwen I

    2015-01-01

    The association of ticks (Acarina) and seabirds provides an intriguing system for assessing the influence of long-distance dispersal on the evolution of parasitic species. Recent research has focused on host-parasite evolutionary relationships and dispersal capacity of ticks parasitising flighted seabirds. Evolutionary research on the ticks of non-flighted seabirds is, in contrast, scarce. We conducted the first phylogeographic investigation of a hard tick species (Ixodes eudyptidis) that parasitises the Little Blue Penguin (Eudyptula minor). Using one nuclear (28S) and two mitochondrial (COI and 16S) markers, we assessed genetic diversity among several populations in Australia and a single population on the South Island of New Zealand. Our results reveal two deeply divergent lineages, possibly representing different species: one comprising all New Zealand samples and some from Australia, and the other representing all other samples from Australian sites. No significant population differentiation was observed among any Australian sites from within each major clade, even those separated by hundreds of kilometres of coastline. In contrast, the New Zealand population was significantly different to all samples from Australia. Our phylogenetic results suggest that the New Zealand and Australian populations are effectively isolated from each other; although rare long-distance dispersal events must occur, these are insufficient to maintain trans-Tasman gene flow. Despite the evidence for limited dispersal of penguin ticks between Australia and New Zealand, we found no evidence to suggest that ticks are unable to disperse shorter distances at sea with their hosts, with no pattern of population differentiation found among Australian sites. Our results suggest that terrestrial seabird parasites may be quite capable of short-distance movements, but only sporadic longer-distance (trans-oceanic) dispersal.

  7. Transoceanic dispersal and subsequent diversification on separate continents shaped diversity of the Xanthoparmelia pulla group (Ascomycota.

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    Guillermo Amo de Paz

    Full Text Available In traditional morphology-based concepts many species of lichenized fungi have world-wide distributions. Molecular data have revolutionized the species delimitation in lichens and have demonstrated that we underestimated the diversity of these organisms. The aim of this study is to explore the phylogeography and the evolutionary patterns of the Xanthoparmelia pulla group, a widespread group of one of largest genera of macrolichens. We used a dated phylogeny based on nuITS and nuLSU rDNA sequences and performed an ancestral range reconstruction to understand the processes and explain their current distribution, dating the divergence of the major lineages in the group. An inferred age of radiation of parmelioid lichens and the age of a Parmelia fossil were used as the calibration points for the phylogeny. The results show that many species of the X. pulla group as currently delimited are polyphyletic and five major lineages correlate with their geographical distribution and the biosynthetic pathways of secondary metabolites. South Africa is the area where the X. pulla group radiated during the Miocene times, and currently is the region with the highest genetic, morphological and chemical diversity. From this center of radiation the different lineages migrated by long-distance dispersal to others areas, where secondary radiations developed. The ancestral range reconstruction also detected that a secondary lineage migrated from Australia to South America via long-distance dispersal and subsequent continental radiation.

  8. Across the Indian Ocean: A remarkable example of trans-oceanic dispersal in an austral mygalomorph spider.

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    Sophie E Harrison

    Full Text Available The Migidae are a family of austral trapdoor spiders known to show a highly restricted and disjunct distribution pattern. Here, we aim to investigate the phylogeny and historical biogeography of the group, which was previously thought to be vicariant in origin, and examine the biogeographic origins of the genus Moggridgea using a dated multi-gene phylogeny. Moggridgea specimens were sampled from southern Australia and Africa, and Bertmainus was sampled from Western Australia. Sanger sequencing methods were used to generate a robust six marker molecular dataset consisting of the nuclear genes 18S rRNA, 28S rRNA, ITS rRNA, XPNPEP3 and H3 and the mitochondrial gene COI. Bayesian and Maximum Likelihood methods were used to analyse the dataset, and the key dispersal nodes were dated using BEAST. Based on our data, we demonstrate that Moggridgea rainbowi from Kangaroo Island, Australia is a valid member of the otherwise African genus Moggridgea. Molecular clock dating analyses show that the inter-specific divergence of M. rainbowi from African congeners is between 2.27-16.02 million years ago (Mya. This divergence date significantly post-dates the separation of Africa from Gondwana (95 Mya and therefore does not support a vicariant origin for Australian Moggridgea. It also pre-dates human colonisation of Kangaroo Island, a result which is further supported by the intra-specific divergence date of 1.10-6.39 Mya between separate populations on Kangaroo Island. These analyses provide strong support for the hypothesis that Moggridgea colonised Australia via long-distance trans-Indian Ocean dispersal, representing the first such documented case in a mygalomorph spider.

  9. Distribution and dispersal of Xylaria endophytes in two tree species in Puerto Rico

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    P. Bayman; D. J. Lodge; P. Angulo-Sandoval; Z. Baez-Ortiz

    1998-01-01

    Xylaria species are common endophytes in tropical plants. It is not known, however, whether transmission of Xylaria occurs horizontally or vertically, whether individual Xylaria strains have wide host ranges or are host-specific, or how they are dispersed. We compared frequency of Xylaria endophytes in leaves and seeds of two tree species in Puerto Rico, Casuarina...

  10. Seed dispersal turns an experimental plantation on degraded land into a novel forest in urban northern Puerto Rico

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    Oscar Abelleira; Elvia J. Meléndez Ackerman; Diana García Montiel; John A. Parrotta

    2015-01-01

    Planting tree species with desirable traits may catalyze forest regeneration in increasingly common degraded lands by restoring soil properties and attracting seed dispersers. We sampled forest regeneration in an experimental plantation of Albizia lebbek, an introduced N-fixing species, on a degraded pasture in northern Puerto Rico, 27 years after its establishment. We...

  11. Transoceanic migration by a 12 g songbird.

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    DeLuca, William V; Woodworth, Bradley K; Rimmer, Christopher C; Marra, Peter P; Taylor, Philip D; McFarland, Kent P; Mackenzie, Stuart A; Norris, D Ryan

    2015-04-01

    Many fundamental aspects of migration remain a mystery, largely due to our inability to follow small animals over vast spatial areas. For more than 50 years, it has been hypothesized that, during autumn migration, blackpoll warblers (Setophaga striata) depart northeastern North America and undertake a non-stop flight over the Atlantic Ocean to either the Greater Antilles or the northeastern coast of South America. Using miniaturized light-level geolocators, we provide the first irrefutable evidence that the blackpoll warbler, a 12 g boreal forest songbird, completes an autumn transoceanic migration ranging from 2270 to 2770 km (mean ± s.d.: 2540 ± 257) and requiring up to 3 days (62 h ± 10) of non-stop flight. This is one of the longest non-stop overwater flights recorded for a songbird and confirms what has long been believed to be one of the most extraordinary migratory feats on the planet. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  12. Excitation Location and Seasonal Variation of Transoceanic Infragravity Waves Observed at an Absolute Pressure Gauge Array

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    Tonegawa, T.; Fukao, Y.; Shiobara, H.; Sugioka, H.; Ito, A.; Yamashita, M.

    2018-01-01

    An array of 10 absolute pressure gauges (APGs) deployed in deep water 50 km east of Aogashima, an island in southern Japan, observed several isolated signals in the infragravity wave (IGW) frequency band (0.002-0.03 Hz) during boreal summer, whereas relatively high IGW energy persisted during boreal winter. The isolated IGW shows dispersion with a delay time of 4-5 days as a function of frequency. Here we estimate the excitation locations of IGWs for the two seasons with estimated incoming direction of IGW, calculation of transoceanic IGW trajectories and propagation times, and spatiotemporal variations of significant wave heights from WAVEWATCH III. In boreal summer, the isolated IGWs are primarily caused by IGW energies excited at the shoreline of South America, based on the following three observations: IGWs observed at the array originated from the east: the easterly ray path from the array reaches South America: and an event-like IGWs were observed at the array when a storm approaches eastward to the shoreline of South America, in which the observed delay time of 4-5 days was also supported by the frequency-dependent calculation of IGW propagation times. In boreal winter, the incessant IGWs consist of transoceanic IGW energies leaked from the shoreline, primarily from North America, and secondly from South America and the western Aleutian Islands.

  13. Juvenile Osprey Navigation during Trans-Oceanic Migration.

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    Travis W Horton

    Full Text Available To compensate for drift, an animal migrating through air or sea must be able to navigate. Although some species of bird, fish, insect, mammal, and reptile are capable of drift compensation, our understanding of the spatial reference frame, and associated coordinate space, in which these navigational behaviors occur remains limited. Using high resolution satellite-monitored GPS track data, we show that juvenile ospreys (Pandion haliaetus are capable of non-stop constant course movements over open ocean spanning distances in excess of 1500 km despite the perturbing effects of winds and the lack of obvious landmarks. These results are best explained by extreme navigational precision in an exogenous spatio-temporal reference frame, such as positional orientation relative to Earth's magnetic field and pacing relative to an exogenous mechanism of keeping time. Given the age (<1 year-old of these birds and knowledge of their hatching site locations, we were able to transform Enhanced Magnetic Model coordinate locations such that the origin of the magnetic coordinate space corresponded with each bird's nest. Our analyses show that trans-oceanic juvenile osprey movements are consistent with bicoordinate positional orientation in transformed magnetic coordinate or geographic space. Through integration of movement and meteorological data, we propose a new theoretical framework, chord and clock navigation, capable of explaining the precise spatial orientation and temporal pacing performed by juvenile ospreys during their long-distance migrations over open ocean.

  14. Forest fragments as barriers to fruit fly dispersal: Anastrepha (Diptera: Tephritidae) populations in orchards and adjacent forest fragments in Puerto Rico.

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    Jenkins, David A; Kendra, Paul E; Van Bloem, Skip; Whitmire, Stefanie; Mizell, Russ; Goenaga, Ricardo

    2013-04-01

    McPhail-type traps baited with ammonium acetate and putrescine were used to monitor populations of Anastrepha obliqua (Macquart) and Anastrepha suspensa (Loew) in two orchards with hosts of these flies (mango, Mangifera indica L., and carambola, Averrhoa carambola L.), as well as in forest fragments bordering these orchards. Contour maps were constructed to measure population distributions in and around orchards. Our results indicate that Anastrepha populations are focused around host fruit in both space and time, that traps do not draw fruit flies away from hosts, even when placed within 15 m of the host, and that lures continue to function for 6 mo in the field. The contour mapping analyses reveal that populations of fruit flies are focused around ovipositional hosts. Although the trapping system does not have a very long effective sampling range, it is ideal, when used in combination with contour analyses, for assessing fine-scale (on the order of meters) population distributions, including identifying resources around which fly populations are focused or, conversely, assessing the effectiveness of management tools. The results are discussed as they pertain to monitoring and detecting Anastrepha spp. with the McPhail-type trap and ammonium acetate and putrescine baiting system and the dispersal of these flies within Puerto Rico.

  15. Diversification dynamics and transoceanic Eurasian-Australian disjunction in the genus Picris (Compositae) induced by the interplay of shifts in intrinsic/extrinsic traits and paleoclimatic oscillations.

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    Slovák, Marek; Kučera, Jaromír; Lack, Hans Walter; Ziffer-Berger, Jotham; Melicharková, Andrea; Záveská, Eliška; Vďačný, Peter

    2018-02-01

    Understanding transcontinental biogeographic patterns has been one of the main foci of the field of biogeography. While multiple explanations for transcontinental disjunctions have been proposed, little is still known about the relative importance of intrinsic and extrinsic traits for the diversification dynamics of disjunct taxa. Here, we study the evolutionary history of the genus Picris L. (Compositae), a great model for investigating the diversification dynamics of transoceanic bipolar disjunct organisms. Ancestral state reconstructions indicate that the most recent common ancestor (MRCA) of Picris was a semelparous and heterocarpic herb that lived in unpredictable environments of North Africa and West Asia. Diversification analyses suggest a significant shift in speciation ca. 1 million years ago, likely associated with the onset of the mid-Pleistocene revolution. Longevity characters are correlated with the evolution of particular fruit types and with environmental conditions. Heterocarpic species are mostly semelparous herbs strongly linked with unpredictable habitats, while homocarpic taxa are mostly iteroparous plants occurring in predictable environments. Binary-state speciation and extinction analyses suggest that homocarpy, iteroparity, and habitats predictability accelerate diversification. Although the combination of homocarpy and iteroparity evolved in several lineages, only members of the P. hieracioides group were able to colonise Eurasia and expand to Australia by transoceanic dispersal. Those findings indicate that large-scale colonisation events depend on a complex interplay of intrinsic and extrinsic factors. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Lagrangian coherent structure assisted path planning for transoceanic autonomous underwater vehicle missions.

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    Ramos, A G; García-Garrido, V J; Mancho, A M; Wiggins, S; Coca, J; Glenn, S; Schofield, O; Kohut, J; Aragon, D; Kerfoot, J; Haskins, T; Miles, T; Haldeman, C; Strandskov, N; Allsup, B; Jones, C; Shapiro, J

    2018-03-15

    Transoceanic Gliders are Autonomous Underwater Vehicles (AUVs) for which there is a developing and expanding range of applications in open-seas research, technology and underwater clean transport. Mature glider autonomy, operating depth (0-1000 meters) and low energy consumption without a CO 2 footprint enable evolutionary access across ocean basins. Pursuant to the first successful transatlantic glider crossing in December 2009, the Challenger Mission has opened the door to long-term, long-distance routine transoceanic AUV missions. These vehicles, which glide through the water column between 0 and 1000 meters depth, are highly sensitive to the ocean current field. Consequently, it is essential to exploit the complex space-time structure of the ocean current field in order to plan a path that optimizes scientific payoff and navigation efficiency. This letter demonstrates the capability of dynamical system theory for achieving this goal by realizing the real-time navigation strategy for the transoceanic AUV named Silbo, which is a Slocum deep-glider (0-1000 m), that crossed the North Atlantic from April 2016 to March 2017. Path planning in real time based on this approach has facilitated an impressive speed up of the AUV to unprecedented velocities resulting in major battery savings on the mission, offering the potential for routine transoceanic long duration missions.

  17. Climate impacts on transocean dispersal and habitat in gray whales from the Pleistocene to 2100

    NARCIS (Netherlands)

    Alter, S Elizabeth; Meyer, Matthias; Post, Klaas; Czechowski, Paul; Gravlund, Peter; Gaines, Cork; Rosenbaum, Howard C; Kaschner, Kristin; Turvey, Samuel T; van der Plicht, Johannes; Shapiro, Beth; Hofreiter, Michael

    2015-01-01

    Arctic animals face dramatic habitat alteration due to ongoing climate change. Understanding how such species have responded to past glacial cycles can help us forecast their response to today's changing climate. Gray whales are among those marine species likely to be strongly affected by Arctic

  18. Global biogeography of scaly tree ferns (Cyatheaceae): evidence for Gondwanan vicariance and limited transoceanic dispersal

    OpenAIRE

    Korall, Petra; Pryer, Kathleen

    2014-01-01

    Aim Scaly tree ferns, Cyatheaceae, are a well-supported group of mostly tree-forming ferns found throughout the tropics, the subtropics and the south-temperate zone. Fossil evidence shows that the lineage originated in the Late Jurassic period. We reconstructed large-scale historical biogeographical patterns of Cyatheaceae and tested the hypothesis that some of the observed distribution patterns are in fact compatible, in time and space, with a vicariance scenario related to the break-up of G...

  19. Transoceanic origin of microendemic and flightless New Caledonian weevils.

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    Toussaint, Emmanuel F A; Tänzler, Rene; Balke, Michael; Riedel, Alexander

    2017-06-01

    The origin of the astonishing New Caledonian biota continues to fuel a heated debate among advocates of a Gondwanan relict scenario and defenders of late oceanic dispersal. Here, we study the origin of New Caledonian Trigonopterus flightless weevils using a multimarker molecular phylogeny. We infer two independent clades of species found in the archipelago. Our dating estimates suggest a Late Miocene origin of both clades long after the re-emergence of New Caledonia about 37 Ma. The estimation of ancestral ranges supports an ancestral origin of the genus in a combined region encompassing Australia and New Guinea with subsequent colonizations of New Caledonia out of New Guinea in the mid-Miocene. The two New Caledonian lineages have had very different evolutionary trajectories. Colonizers belonging to a clade of foliage dwellers greatly diversified, whereas species inhabiting leaf-litter have been less successful.

  20. Improved Phase Corrections for Transoceanic Tsunami Data in Spatial and Temporal Source Estimation: Application to the 2011 Tohoku Earthquake

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    Ho, Tung-Cheng; Satake, Kenji; Watada, Shingo

    2017-12-01

    Systemic travel time delays of up to 15 min relative to the linear long waves for transoceanic tsunamis have been reported. A phase correction method, which converts the linear long waves into dispersive waves, was previously proposed to consider seawater compressibility, the elasticity of the Earth, and gravitational potential change associated with tsunami motion. In the present study, we improved this method by incorporating the effects of ocean density stratification, actual tsunami raypath, and actual bathymetry. The previously considered effects amounted to approximately 74% for correction of the travel time delay, while the ocean density stratification, actual raypath, and actual bathymetry, contributed to approximately 13%, 4%, and 9% on average, respectively. The improved phase correction method accounted for almost all the travel time delay at far-field stations. We performed single and multiple time window inversions for the 2011 Tohoku tsunami using the far-field data (>3 h travel time) to investigate the initial sea surface displacement. The inversion result from only far-field data was similar to but smoother than that from near-field data and all stations, including a large sea surface rise increasing toward the trench followed by a migration northward along the trench. For the forward simulation, our results showed good agreement between the observed and computed waveforms at both near-field and far-field tsunami gauges, as well as with satellite altimeter data. The present study demonstrates that the improved method provides a more accurate estimate for the waveform inversion and forward prediction of far-field data.

  1. Numerical simulation of transoceanic propagation and run-up of tsunami

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Yong-Sik; Yoon Sung-Bum [Hanyang University, Seoul(Korea)

    2001-04-30

    The propagation and associated run-up process of tsunami are numerically investigated in this study. A transoceanic propagation model is first used to simulate the distant propagation of tsunamis. An inundation model is then employed to simulate the subsequent run-up process near coastline. A case study is done for the 1960 Chilean tsunami. A detailed maximum inundation map at Hilo Bay is obtained and compared with field observation and other numerical model, predictions. A very reasonable agreement is observed. (author). refs., tabs., figs.

  2. DNA capture reveals transoceanic gene flow in endangered river sharks.

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    Li, Chenhong; Corrigan, Shannon; Yang, Lei; Straube, Nicolas; Harris, Mark; Hofreiter, Michael; White, William T; Naylor, Gavin J P

    2015-10-27

    For over a hundred years, the "river sharks" of the genus Glyphis were only known from the type specimens of species that had been collected in the 19th century. They were widely considered extinct until populations of Glyphis-like sharks were rediscovered in remote regions of Borneo and Northern Australia at the end of the 20th century. However, the genetic affinities between the newly discovered Glyphis-like populations and the poorly preserved, original museum-type specimens have never been established. Here, we present the first (to our knowledge) fully resolved, complete phylogeny of Glyphis that includes both archival-type specimens and modern material. We used a sensitive DNA hybridization capture method to obtain complete mitochondrial genomes from all of our samples and show that three of the five described river shark species are probably conspecific and widely distributed in Southeast Asia. Furthermore we show that there has been recent gene flow between locations that are separated by large oceanic expanses. Our data strongly suggest marine dispersal in these species, overturning the widely held notion that river sharks are restricted to freshwater. It seems that species in the genus Glyphis are euryhaline with an ecology similar to the bull shark, in which adult individuals live in the ocean while the young grow up in river habitats with reduced predation pressure. Finally, we discovered a previously unidentified species within the genus Glyphis that is deeply divergent from all other lineages, underscoring the current lack of knowledge about the biodiversity and ecology of these mysterious sharks.

  3. The first record of a trans-oceanic sister-group relationship between obligate vertebrate troglobites.

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    Prosanta Chakrabarty

    Full Text Available We show using the most complete phylogeny of one of the most species-rich orders of vertebrates (Gobiiformes, and calibrations from the rich fossil record of teleost fishes, that the genus Typhleotris, endemic to subterranean karst habitats in southwestern Madagascar, is the sister group to Milyeringa, endemic to similar subterranean systems in northwestern Australia. Both groups are eyeless, and our phylogenetic and biogeographic results show that these obligate cave fishes now found on opposite ends of the Indian Ocean (separated by nearly 7,000 km are each others closest relatives and owe their origins to the break up of the southern supercontinent, Gondwana, at the end of the Cretaceous period. Trans-oceanic sister-group relationships are otherwise unknown between blind, cave-adapted vertebrates and our results provide an extraordinary case of Gondwanan vicariance.

  4. Trans-oceanic transport of {sup 137}Cs from the Fukushima nuclear accident and impact of hypothetical Fukushima-like events of future nuclear plants in Southern China

    Energy Technology Data Exchange (ETDEWEB)

    Wai, Ka-Ming, E-mail: bhkmwai@cityu.edu.hk [Department of Geological and Mining Engineering and Sciences, Michigan Technological University, Houghton, MI (United States); Department of Physics and Material Science, City University of Hong Kong, Hong Kong (China); Yu, Peter K.N. [Department of Physics and Material Science, City University of Hong Kong, Hong Kong (China)

    2015-03-01

    A Lagrangian model was adopted to assess the potential impact of {sup 137}Cs released from hypothetical Fukushima-like accidents occurring on three potential nuclear power plant sites in Southern China in the near future (planned within 10 years) in four different seasons. The maximum surface (0–500 m) {sup 137}Cs air concentrations would be reached 10 Bq m{sup −3} near the source, comparable to the Fukushima case. In January, Southeast Asian countries would be mostly affected by the radioactive plume due to the effects of winter monsoon. In April, the impact would be mainly on Southern and Northern China. Debris of radioactive plume (∼ 1 mBq m{sup −3}) would carry out long-range transport to North America. The area of influence would be the smallest in July due to the frequent and intense wet removal events by trough of low pressure and tropical cyclone. The maximum worst-case areas of influence were 2382000, 2327000, 517000 and 1395000 km{sup 2} in January, April, July and October, respectively. Prior to the above calculations, the model was employed to simulate the trans-oceanic transport of {sup 137}Cs from the Fukushima nuclear accident. Observed and modeled {sup 137}Cs concentrations were comparable. Sensitivity runs were performed to optimize the wet scavenging parameterization. The adoption of higher-resolution (1° × 1°) meteorological fields improved the prediction. The computed large-scale plume transport pattern over the Pacific Ocean was compared with that reported in the literature. - Highlights: • A Lagrangian model was used to predict the dispersion of {sup 137}Cs from plant accident. • Observed and modeled {sup 137}Cs concentrations were comparable for the Fukushima accident. • The maximum surface concentrations could reach 10 Bq m{sup −3} for the hypothetical case. • The hypothetical radiative plumes could impact E/SE Asia and N. America.

  5. Zdrowie Psychiczne w żegludze transoceanicznej = Mental Health in transoceanic sailing

    Directory of Open Access Journals (Sweden)

    Mariusz Julian Czarnecki

    2016-07-01

    stresem w badanej grupie, oraz świadomość zachowania prozdrowotnego mającego wpływ na potencjał zdrowia. Wnioski Osoby pełniące funkcję Kapitana na rejsach oceanicznych, wykazały się znajomością własnych stresorów towarzyszących podczas żeglugi. Dodatkowo wykazały się działaniami prowadzącymi do zachowania potencjału zdrowotnego. Osoby badane nie wykazały reakcji antyzdrowotnych i tendencji prowadzących do wystąpienia skutków powodowanych przez dystres.   Słowa kluczowe: zdrowie psychiczne, stres, potencjał zdrowotny, żeglarstwo.         Abstract   Introduction The awareness of the stressors and how to cope with stressful situations has an impact on the health of people who practice the professions associated with a great responsibility for the health and lives of others, such as, medical consultants, nurses and firefighters. Practising the profession of yacht captain is associated with responsibility for the crew and a sailing vessel in various conditions, and therefore is inseparably linked with the occurrence of stressful situations. To the best of our knowledge, so far, little studies, in terms of stress, were conducted on captains, taking long cruises, such as transoceanic sailing,. Materials and methods In the presented work, 5 captains were studied. The qualitative research, with the use of an expert narrative interview, was used. The open-depth interviews with selected group of captains were performed, with a particular attention to the, indicated by responders, stressors occurring during transoceanic sailing. In addition, the level of perception and coping with stress in the study group, and awareness of healthy behaviour, affecting health of responders were discussed. Results The responders demonstrated the knowledge of the stressors associated with their profession. In addition, they demonstrated the ability to take action, aimed to preserve the health potential. Moreover, the subjects showed no unhealthy tendencies leading to

  6. Transoceanic drift and the domestication of African bottle gourds in the Americas.

    Science.gov (United States)

    Kistler, Logan; Montenegro, Alvaro; Smith, Bruce D; Gifford, John A; Green, Richard E; Newsom, Lee A; Shapiro, Beth

    2014-02-25

    Bottle gourd (Lagenaria siceraria) was one of the first domesticated plants, and the only one with a global distribution during pre-Columbian times. Although native to Africa, bottle gourd was in use by humans in east Asia, possibly as early as 11,000 y ago (BP) and in the Americas by 10,000 BP. Despite its utilitarian importance to diverse human populations, it remains unresolved how the bottle gourd came to be so widely distributed, and in particular how and when it arrived in the New World. A previous study using ancient DNA concluded that Paleoindians transported already domesticated gourds to the Americas from Asia when colonizing the New World [Erickson et al. (2005) Proc Natl Acad Sci USA 102(51):18315-18320]. However, this scenario requires the propagation of tropical-adapted bottle gourds across the Arctic. Here, we isolate 86,000 base pairs of plastid DNA from a geographically broad sample of archaeological and living bottle gourds. In contrast to the earlier results, we find that all pre-Columbian bottle gourds are most closely related to African gourds, not Asian gourds. Ocean-current drift modeling shows that wild African gourds could have simply floated across the Atlantic during the Late Pleistocene. Once they arrived in the New World, naturalized gourd populations likely became established in the Neotropics via dispersal by megafaunal mammals. These wild populations were domesticated in several distinct New World locales, most likely near established centers of food crop domestication.

  7. Transoceanic drift and the domestication of African bottle gourds in the Americas

    Science.gov (United States)

    Kistler, Logan; Montenegro, Álvaro; Smith, Bruce D.; Gifford, John A.; Green, Richard E.; Newsom, Lee A.; Shapiro, Beth

    2014-01-01

    Bottle gourd (Lagenaria siceraria) was one of the first domesticated plants, and the only one with a global distribution during pre-Columbian times. Although native to Africa, bottle gourd was in use by humans in east Asia, possibly as early as 11,000 y ago (BP) and in the Americas by 10,000 BP. Despite its utilitarian importance to diverse human populations, it remains unresolved how the bottle gourd came to be so widely distributed, and in particular how and when it arrived in the New World. A previous study using ancient DNA concluded that Paleoindians transported already domesticated gourds to the Americas from Asia when colonizing the New World [Erickson et al. (2005) Proc Natl Acad Sci USA 102(51):18315–18320]. However, this scenario requires the propagation of tropical-adapted bottle gourds across the Arctic. Here, we isolate 86,000 base pairs of plastid DNA from a geographically broad sample of archaeological and living bottle gourds. In contrast to the earlier results, we find that all pre-Columbian bottle gourds are most closely related to African gourds, not Asian gourds. Ocean-current drift modeling shows that wild African gourds could have simply floated across the Atlantic during the Late Pleistocene. Once they arrived in the New World, naturalized gourd populations likely became established in the Neotropics via dispersal by megafaunal mammals. These wild populations were domesticated in several distinct New World locales, most likely near established centers of food crop domestication. PMID:24516122

  8. Quinine, Malaria, and the Cinchona Bureau: Marketing Practices and Knowledge Circulation in a Dutch Transoceanic Cinchona-Quinine Enterprise (1920s-30s).

    Science.gov (United States)

    Van Der Hoogte, Arjo Roersch; Pieters, Toine

    2016-04-01

    In this study, we will show how a Dutch pharmaceutical consortium of cinchona producers and quinine manufacturers was able to capitalize on one of the first international public health campaigns to fight malaria, thereby promoting the sale of quinine, an antimalarial medicine. During the 1920s and 1930s, the international markets for quinine were controlled by this Dutch consortium, which was a transoceanic cinchona-quinine enterprise centered in the Cinchona Bureau in the Netherlands. We will argue that during the interwar period, the Cinchona Bureau became the decision-making center of this Dutch cinchona-quinine pharmaceutical enterprise and monopolized the production and trade of an essential medicine. In addition, we will argue that capitalizing on the international public health campaign in the fight against malaria by the Dutch cinchona-quinine enterprise via the Cinchona Bureau can be regarded as an early example of corporate colonization of public health by a private pharmaceutical consortium. Furthermore, we will show how commercial interests prevailed over scientific interests within the Dutch cinchona-quinine consortium, thus interfering with and ultimately curtailing the transoceanic circulation of knowledge in the Dutch empire. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. REFERENCIAL TEÓRICO

    Directory of Open Access Journals (Sweden)

    Mariana Fernandes de Souza

    Full Text Available A autora aborda o conhecimento teórico na enfermagem, focaliza algumas publicações consideradas importantes sobre o mesmo e tece considerações sobre modelos conceituais e teorias como referencial para atuação profissional.

  10. Puerto Rico, humedales [Puerto Rico, wetlands

    Science.gov (United States)

    Adams, D. Briane; Hefner, John M.; Dopazo, Teresa

    1999-01-01

    La isla de Puerto Rico, localizada al noreste del Mar Caribe y sus islas principales, Vieques, Culebra e Isla de Mona, poseen humedales en abundancia . El clima subtropical, la lluvia abundante y las complejas formas topográficas y geológicas de estas islas dan origen a los humedales, que varían desde los raros e inusuales bosques cubiertos por nubes en las tierras altas, hasta los extensos manglares, yerbas marinas y arrecifes de coral a lo largo de las costas Norte y Sur. Sin embargo, los humedales en Puerto Rico han disminuido en los últimos siglos como resultado del aumento en el desarrollo agrícola, poblacional y turístico. Algunos tipos de humedales como los bosques de palo de pollo (Pterocarpus officinalis) se han reducido a sólo unos pocos remanentes (figura 1).Biológicamente hablando, los humedales de las islas están entre las áreas más productivas. Los humedales asociados con el bosque pluvial en las tierras altas del interior de Puerto Rico contienen varias plantas raras y especies de animales que no se encuentran en otras partes de la Isla. El agua de escorrentía proveniente de los humedales en las partes altas de la Isla proveen una fuente de agua que utilizan varias ciudades para abasto público. Los humedales costeros como los mangles, los colchones de yerbas marinas y los arrecifes de coral proveen áreas para la reproducción y crianza de varios peces, crustáceos y otras especies en la cadena alimenticia (López y otros, 1988). De esta manera, los humedales costeros contribuyen a la productividad biológica de las aguas llanas del mar alrededor de las islas . Los humedales también estabilizan las costas atrapando y reteniendo sedimentos no consolidados y amortiguan la acción de las olas y de las tormentas que tienen el potencial de causar daños en la zona.El valor de los humedales de Puerto Rico para la vida silvestre está muy bien documentado . Por ejemplo, las salinas de Cabo Rojo, en la costa suroeste, proveen áreas para el

  11. Intercontinental dispersal by a microendemic burrowing reptile (Dibamidae).

    Science.gov (United States)

    Townsend, Ted M; Leavitt, Dean H; Reeder, Tod W

    2011-09-07

    Intercontinental dispersal via land bridge connections has been important in the biogeographic history of many Holarctic plant and animal groups. Likewise, some groups appear to have accomplished trans-oceanic dispersal via rafting. Dibamid lizards are a clade of poorly known fossorial, essentially limbless species traditionally split into two geographically disjunct genera: Dibamus comprises approximately 20 Southeast Asian species, many of which have very limited geographical distributions, and the monotypic genus Anelytropsis occupies a small area of northeastern Mexico. Although no formal phylogeny of the group exists, a sister-taxon relationship between the two genera has been assumed based on biogeographic considerations. We used DNA sequence data from one mitochondrial and six nuclear protein-coding genes to construct a phylogeny of Dibamidae and to estimate divergence times within the group. Surprisingly, sampled Dibamus species form two deeply divergent, morphologically conserved and geographically concordant clades, one of which is the sister taxon of Anelytropsis papillosus. Our analyses indicate Palaearctic to Nearctic Beringian dispersal in the Late Palaeocene to Eocene. Alternatively, a trans-Pacific rafting scenario would extend the upper limit on dispersal to the Late Cretaceous. Either scenario constitutes a remarkable long-distance dispersal in what would seem an unlikely candidate.

  12. Warning system based on theoretical-experimental study of dispersion of soluble pollutants in rivers Sistema de alerta com base em estudo teórico-experimental de dispersão de poluentes solúveis em rios

    Directory of Open Access Journals (Sweden)

    Celso B. de M. Ribeiro

    2011-10-01

    Full Text Available Information about capacity of transport and dispersion of soluble pollutants in natural streams are important in the management of water resources, especially in planning preventive measures to minimize the problems caused by accidental or intentional waste, in public health and economic activities that depend on the use of water. Considering this importance, this study aimed to develop a warning system for rivers, based on experimental techniques using tracers and analytical equations of one-dimensional transport of soluble pollutants conservative, to subsidizing the decision-making in the management of water resources. The system was development in JAVA programming language and MySQL database can predict the travel time of pollutants clouds from a point of eviction and graphically displays the temporal distribution of concentrations of passage clouds, in a particular location, downstream from the point of its launch.Informações sobre a capacidade de transporte e dispersão de poluentes solúveis em cursos de água naturais são importantes no gerenciamento dos recursos hídricos, principalmente no planejamento preventivo de medidas que visem a minimizar problemas à saúde pública e às atividades econômicas que dependem do uso da água, ocasionados por despejos acidentais ou intencionais. Considerando tal importância, este trabalho teve como objetivo desenvolver um sistema de alerta para rios, com base em resultados experimentais, utilizando técnicas de traçadores e equações analíticas de transporte unidimensional de poluentes solúveis conservativos, visando a subsidiar a tomada de decisão no gerenciamento dos recursos hídricos. O sistema desenvolvido em linguagem de programação JAVA e banco de dados MySQL permite prever o tempo de percurso da nuvem de poluentes a partir de um ponto de despejo de um poluente e apresenta, graficamente, a distribuição temporal de concentrações da passagem da nuvem, em um determinado local,

  13. Native rodent species are unlikely sources of infection for Leishmania (Viannia braziliensis along the Transoceanic Highway in Madre de Dios, Peru.

    Directory of Open Access Journals (Sweden)

    Lisa A Shender

    Full Text Available An estimated 2.3 million disability-adjusted life years are lost globally from leishmaniasis. In Peru's Amazon region, the department of Madre de Dios (MDD rises above the rest of the country in terms of the annual incidence rates of human leishmaniasis. Leishmania (Viannia braziliensis is the species most frequently responsible for the form of disease that results in tissue destruction of the nose and mouth. However, essentially nothing is known regarding the reservoirs of this vector-borne, zoonotic parasite in MDD. Wild rodents have been suspected, or proven, to be reservoirs of several Leishmania spp. in various ecosystems and countries. Additionally, people who live or work in forested terrain, especially those who are not regionally local and whose immune systems are thus naïve to the parasite, are at most risk for contracting L. (V. braziliensis. Hence, the objective of this study was to collect tissues from wild rodents captured at several study sites along the Amazonian segment of the newly constructed Transoceanic Highway and to use molecular laboratory techniques to analyze samples for the presence of Leishmania parasites. Liver tissues were tested via polymerase chain reaction from a total of 217 rodents; bone marrow and skin biopsies (ear and tail were also tested from a subset of these same animals. The most numerous rodent species captured and tested were Oligoryzomys microtis (40.7%, Hylaeamys perenensis (15.7%, and Proechimys spp. (12%. All samples were negative for Leishmania, implying that although incidental infections may occur, these abundant rodent species are unlikely to serve as primary reservoirs of L. (V. braziliensis along the Transoceanic Highway in MDD. Therefore, although these rodent species may persist and even thrive in moderately altered landscapes, we did not find any evidence to suggest they pose a risk for L. (V. braziliensis transmission to human inhabitants in this highly prevalent region.

  14. Native rodent species are unlikely sources of infection for Leishmania (Viannia) braziliensis along the Transoceanic Highway in Madre de Dios, Peru.

    Science.gov (United States)

    Shender, Lisa A; De Los Santos, Maxy; Montgomery, Joel M; Conrad, Patricia A; Ghersi, Bruno M; Razuri, Hugo; Lescano, Andres G; Mazet, Jonna A K

    2014-01-01

    An estimated 2.3 million disability-adjusted life years are lost globally from leishmaniasis. In Peru's Amazon region, the department of Madre de Dios (MDD) rises above the rest of the country in terms of the annual incidence rates of human leishmaniasis. Leishmania (Viannia) braziliensis is the species most frequently responsible for the form of disease that results in tissue destruction of the nose and mouth. However, essentially nothing is known regarding the reservoirs of this vector-borne, zoonotic parasite in MDD. Wild rodents have been suspected, or proven, to be reservoirs of several Leishmania spp. in various ecosystems and countries. Additionally, people who live or work in forested terrain, especially those who are not regionally local and whose immune systems are thus naïve to the parasite, are at most risk for contracting L. (V.) braziliensis. Hence, the objective of this study was to collect tissues from wild rodents captured at several study sites along the Amazonian segment of the newly constructed Transoceanic Highway and to use molecular laboratory techniques to analyze samples for the presence of Leishmania parasites. Liver tissues were tested via polymerase chain reaction from a total of 217 rodents; bone marrow and skin biopsies (ear and tail) were also tested from a subset of these same animals. The most numerous rodent species captured and tested were Oligoryzomys microtis (40.7%), Hylaeamys perenensis (15.7%), and Proechimys spp. (12%). All samples were negative for Leishmania, implying that although incidental infections may occur, these abundant rodent species are unlikely to serve as primary reservoirs of L. (V.) braziliensis along the Transoceanic Highway in MDD. Therefore, although these rodent species may persist and even thrive in moderately altered landscapes, we did not find any evidence to suggest they pose a risk for L. (V.) braziliensis transmission to human inhabitants in this highly prevalent region.

  15. Puerto Rico Soil Erodibility (Kffact)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Puerto Rico soil erodibility (Kffactor) - low values indicate low vulnerability to erosion, higher values mean higher susceptibility to runoff.

  16. Columbia University Puerto Rico Study.

    Data.gov (United States)

    U.S. Environmental Protection Agency — Lifetime childhood asthma prevalence (LCAP) percentages in Puerto Rico Health Regions (HR) are substantially higher in northeastern vs. southwestern HR. Higher...

  17. Los insectos de Puerto Rico

    Science.gov (United States)

    J.A. Torres; S. Medina Gaud

    1998-01-01

    This paper is a brief summary of the natural history and importance of the insects of Puerto Rico. We briefly discuss the orders of insects present in Puerto Rico and some of their families. Where possible, we have tried to avoid technical terms for better comprehension of a general audience. We present the observations or characteristics of insects that humans admire...

  18. Out of Africa:Miocene Dispersal, Vicariance, and Extinction within Hyacinthaceae Subfamily Urgineoideae

    Institute of Scientific and Technical Information of China (English)

    Syed Shujait Ali; Martin Pfosser; Wolfgang Wetschnig; Mario MartnezAzorn; Manuel B. Crespo; Yan Yu

    2013-01-01

    Disjunct distribution patterns in plant lineages are usually explained according to three hypotheses:vicariance, geodispersal, and long-distance dispersal. The role of these hypotheses is tested in Urgineoideae (Hyacinthaceae), a subfamily disjunctly distributed in Africa, Madagascar, India, and the Mediterranean region. The potential ancestral range, dispersal routes, and factors responsible for the current distribution in Urgineoideae are investigated using divergence time estimations. Urgineoideae originated in Southern Africa approximately 48.9 Mya. Two independent dispersal events in the Western Mediterranean region possibly occurred during Early Oligocene and Miocene (29.9-8.5 Mya) via Eastern and Northwestern Africa. A dispersal from Northwestern Africa to India could have occurred between 16.3 and 7.6 Mya. Vicariance and extinction events occurred approximately 21.6 Mya. Colonization of Madagascar occurred between 30.6 and 16.6 Mya, after a single transoceanic dispersal event from Southern Africa. The current disjunct distributions of Urgineoideae are not satisfactorily explained by Gondwana fragmentation or dispersal via boreotropical forests, due to the younger divergence time estimates. The flattened winged seeds of Urgineoideae could have played an important role in long-distance dispersal by strong winds and big storms, whereas geodispersal could have also occurred from Southern Africa to Asia and the Mediterranean region via the so-called arid and high-altitude corridors.

  19. Hydrodynamic disperser

    Energy Technology Data Exchange (ETDEWEB)

    Bulatov, A.I.; Chernov, V.S.; Prokopov, L.I.; Proselkov, Yu.M.; Tikhonov, Yu.P.

    1980-01-15

    A hydrodynamic disperser is suggested which contains a housing, slit nozzles installed on a circular base arranged opposite from each other, resonators secured opposite the nozzle and outlet sleeve. In order to improve the effectiveness of dispersion by throttling the flow, each resonator is made in the form of a crimped plate with crimpings that decrease in height in a direction towards the nozzle.

  20. Dispersion Forces

    CERN Document Server

    Buhmann, Stefan Yoshi

    2012-01-01

    In this book, a modern unified theory of dispersion forces on atoms and bodies is presented which covers a broad range of advanced aspects and scenarios. Macroscopic quantum electrodynamics is shown to provide a powerful framework for dispersion forces which allows for discussing general properties like their non-additivity and the relation between microscopic and macroscopic interactions. It is demonstrated how the general results can be used to obtain dispersion forces on atoms in the presence of bodies of various shapes and materials. Starting with a brief recapitulation of volume I, this volume II deals especially with bodies of irregular shapes, universal scaling laws, dynamical forces on excited atoms, enhanced forces in cavity quantum electrodynamics, non-equilibrium forces in thermal environments and quantum friction. The book gives both the specialist and those new to the field a thorough overview over recent results in the field. It provides a toolbox for studying dispersion forces in various contex...

  1. HINTS Puerto Rico: Final Report

    Science.gov (United States)

    This final report describes HINTS implementation in Puerto Rico. The report addresses sampling; staffing, training and management of data collection; calling protocol; findings from the CATI Operations, and sample weights.

  2. The evolution of Cayaponia (Cucurbitaceae): Repeated shifts from bat to bee pollination and long-distance dispersal to Africa 2-5 million years ago.

    Science.gov (United States)

    Duchen, Pablo; Renner, Susanne S

    2010-07-01

    The Cucurbitaceae genus Cayaponia comprises ∼60 species that occur from Uruguay to the southern United States and the Caribbean; C. africana occurs in West Africa and on Madagascar. Pollination is by bees or bats, raising the question of the evolutionary direction and frequency of pollinator shifts. Studies that investigated such shifts in other clades have suggested that bat pollination might be an evolutionary end point. • Plastid and nuclear DNA sequences were obtained for 50 accessions representing 30 species of Cayaponia and close relatives, and analyses were carried out to test monophyly, infer divergence times, and reconstruct ancestral states for habitat preferences and pollination modes. • The phylogeny shows that Cayaponia is monophyletic as long as Selysia (a genus with four species from Central and South America) is included. The required nomenclatural transfers are made in this paper. African and Madagascan accessions of C. africana form a clade that is part of a polytomy with Caribbean and South American species, and the inferred divergence time of 2-5 Ma implies a transoceanic dispersal event from the New World to Africa. The ancestral state reconstructions suggest that Cayaponia originated in tropical forests from where open savannas were reached several times and that bee pollination arose from bat pollination, roughly concomitant with the shifts from forests to savanna habitats. • Cayaponia provides the first example of evolutionary transitions from bat to bee pollination as well as another instance of transoceanic dispersal from the New World to Africa.

  3. Chemical dispersants

    NARCIS (Netherlands)

    Rahsepar, Shokouhalsadat; Smit, Martijn P.J.; Murk, Albertinka J.; Rijnaarts, Huub H.M.; Langenhoff, Alette A.M.

    2016-01-01

    Chemical dispersants were used in response to the Deepwater Horizon oil spill in the Gulf of Mexico, both at the sea surface and the wellhead. Their effect on oil biodegradation is unclear, as studies showed both inhibition and enhancement. This study addresses the effect of Corexit on oil

  4. The Indians of Puerto Rico.

    Science.gov (United States)

    Saunders, Robert; And Others

    Produced for use in a coordinated program of studies for students in the Connecticut Migratory Children's Program and for other students whose native language is Spanish, this book about the Indians of Puerto Rico is intended as supplementary reading material for pre-school through fifth grade. The book, illustrated with black and white drawings,…

  5. Cobertura desarrollada de Puerto Rico

    Science.gov (United States)

    William A. Gould; Sebastian Martinuzzi; Olga M. Ramos Gonzalez

    2008-01-01

    Este mapa representa la cobertura desarrollada en Puerto Rico (Martinuzzi et al. 2007). Cobertura desarrollada se define aqui como areas urbanas, construidas y sin vegetacion, que resultan de actividad humana. Tipicamente, estas incluyen estructuras construidas, concreto, asfalto, u otra infraestructura. La cobertura desarrollada se creo mediante el analisis de...

  6. 40 CFR 131.40 - Puerto Rico

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Puerto Rico 131.40 Section 131.40... Federally Promulgated Water Quality Standards § 131.40 Puerto Rico (a) Use designations for marine waters. In addition to the Commonwealth's adopted use designations, the following waterbodies in Puerto Rico...

  7. Drinking and Driving in Puerto Rico.

    Science.gov (United States)

    Caetano, Raul; Vaeth, Patrice A C; Romano, Eduardo; Canino, Glorisa

    2018-01-09

    Epidemiological information is lacking for driving under the influence of alcohol (DUI) in Puerto Rico. To examine the prevalence and correlates of DUI in Puerto Rico. Data are from a household sample of 1510 individuals, aged 18-64 years in San Juan, Puerto Rico. The response rate was 83%. The rate of 12 month self-reported DUI was 20% among men and 8% among women (p Puerto Rico was high, but the proportion of people arrested for DUI in a span of 12 months or during their lifetime was low. Stricter enforcement of DUI laws may be necessary to minimize DUI in urban Puerto Rico.

  8. Canyons off northwest Puerto Rico

    International Nuclear Information System (INIS)

    Gardner, W.D.; Glover, L.K.; Hollister, C.D.

    1980-01-01

    The Nuclear-Research Submarine NR-1 was used to study morphoplogy, sediment, and sediment-water interactions off the northwest coast of Puerto Rico. New detailed bathymetry from the surface-support ship, USS Portland, shows several submarine canyons in the area, some of them unreported previously. The north coast canyons, Arecibo, Tiberones and Quebradillas, are primarily erosional features although no recent turbidity-current evidence is seen. The canyons are presently filling with river-transported sediments. (orig./ME)

  9. Dispersion strengthening

    International Nuclear Information System (INIS)

    Scattergood, R.O.; Das, E.S.P.

    1976-01-01

    Using digital computer-based methods, models for dispersion strengthening can now be developed which take into account many of the important effects that have been neglected in the past. In particular, the self interaction of a dislocation can be treated, and a computer simulation method was developed to determine the flow stress of a random distribution of circular, impenetrable obstacles, taking into account all such interactions. The flow stress values depended on the obstacle sizes and spacings, over and above the usual 1/L dependence where L is the average obstacle spacing. From an analysis of the results, it was found that the main effects of the self interactions can be captured in a line tension analogue in which the obstacles appear to be penetrable

  10. Hydrodynamic dispersion

    International Nuclear Information System (INIS)

    Pryce, M.H.L.

    1985-01-01

    A dominant mechanism contributing to hydrodynamic dispersion in fluid flow through rocks is variation of travel speeds within the channels carrying the fluid, whether these be interstices between grains, in granular rocks, or cracks in fractured crystalline rocks. The complex interconnections of the channels ensure a mixing of those parts of the fluid which travel more slowly and those which travel faster. On a macroscopic scale this can be treated statistically in terms of the distribution of times taken by a particle of fluid to move from one surface of constant hydraulic potential to another, lower, potential. The distributions in the individual channels are such that very long travel times make a very important contribution. Indeed, while the mean travel time is related to distance by a well-defined transport speed, the mean square is effectively infinite. This results in an asymmetrical plume which differs markedly from a gaussian shape. The distribution of microscopic travel times is related to the distribution of apertures in the interstices, or in the microcracks, which in turn are affected in a complex way by the stresses acting on the rock matrix

  11. The Puerto Rico Healthcare Crisis.

    Science.gov (United States)

    Roman, Jesse

    2015-12-01

    The Commonwealth of Puerto Rico is an organized nonincorporated territory of the United States with a population of more than 3.5 million U.S. citizens. The island has been the focus of much recent attention due to the recent default on its debt (estimated at more than $70 billion), high poverty rates, and increasing unemployment. Less attention, however, has been given to the island's healthcare system, which many believe is on the verge of collapsing. Healthcare makes up 20% of the Puerto Rican economy, and this crisis affects reimbursement rates for physicians while promoting the disintegration of the island's healthcare infrastructure. A major contributor relates to a disparity in federal funding provided to support the island's healthcare system when compared with that provided to the states in the mainland and Hawaii. Puerto Rico receives less federal funding for healthcare than the other 50 states and the District of Columbia even though it pays its share of social security and Medicare taxes. To make matters worse, the U.S. Center for Medicaid and Medicare Services is planning soon to implement another 11% cut in Medical Advantage reimbursements. This disparity in support for healthcare is considered responsible for ∼$25 billion of Puerto Rico's total debt. The impact of these events on the health of Puerto Ricans in the island cannot be entirely predicted, but the loss of healthcare providers and diminished access to care are a certainty, and quality care will suffer, leading to serious implications for those with chronic medical disorders including respiratory disease.

  12. Los bosques de Puerto Rico, 2009

    Science.gov (United States)

    Humfredo Marcano Vega; Thomas J. Brandeis; Jeffery A. Turner; No Other

    2015-01-01

    Este informe presenta los resultados del cuarto inventario forestal de las islas del Estado Libre Asociado de Puerto Rico. El área de bosque en la isla grande de Puerto Rico se mantuvo constante o aumentó ligeramente del año 2004 al 2009. Este cambio parece indicar que la tasa de incremento de cubierta forestal en la isla grande de Puerto Rico ha disminuido desde que...

  13. Manatee mortality in Puerto Rico

    Science.gov (United States)

    Mignucci-Giannoni, A. A.; Montoya-Ospina, R. A.; Jimenez-Marrero, N. M.; Rodriguez-Lopez, M.; Williams, E.H.; Bonde, R.K.

    2000-01-01

    The most pressing problem in the effective management of the West Indian manatee (Trichechus manatus) in Puerto Rico is mortality due to human activities. We assessed 90 cases of manatee strandings in Puerto Rico based on historical data and a coordinated carcass salvage effort from 1990 through 1995. We determined patterns of mortality, including type of event, condition of carcasses, spatial and temporal distribution, gender, size/age class, and the cause of death. The spatial distribution of stranding events was not uniform, with the north, northeast, and south coasts having the highest numbers. Six clusters representing the highest incidence included the areas of Fajardo and Ceiba, Bahia de Jobos, Toa Baja, Guayanilla, Cabo Rojo, and Rio Grande to Luquillo. The number of reported cases has increased at an average rate of 9.6%/yr since 1990. The seasonality of stranding events showed a bimodal pattern, from February through April and in August and September. Most identified causes of death were due to human interaction, especially captures and watercraft collisions. Natural causes usually involved dependent calves. From 1990 through 1995, most deaths were attributed to watercraft collisions. A reduction in anthropogenic mortality of this endangered species can be accomplished only through education and a proactive management and conservation plan that includes law enforcement, mortality assessment, scientific research, rescue and rehabilitation, and inter- and intraagency cooperation.

  14. Seed dispersal in fens

    NARCIS (Netherlands)

    Middleton, Beth; van Diggelen, Rudy; Jensen, Kai

    Question: How does seed dispersal reduce fen isolation and contribute to biodiversity? Location: European and North American fens. Methods: This paper reviews the literature on seed dispersal to fens. Results: Landscape fragmentation may reduce dispersal opportunities thereby isolating fens and

  15. Duelo lírico

    Directory of Open Access Journals (Sweden)

    Juan Casis

    1982-01-01

    Full Text Available Juan Casís, editor Contiene: -El centenario o la generación polemista / Javier Arango Ferrer -Prólogo / Roberto Liévano -A un gran poeta / Un poeta oscuro -A un poeta oscuro / Eduardo Castillo -A un poeta pequeño / Un poeta oscuro -Al poeta E. C. / Luis Paredes -A un poeta oscuro y pequeño / Eduardo Castillo -Un sonámbulo / Un poeta oscuro -A dos poetas líricos / Joaquin Güell -La tregua de Dios / Miguel Rasch Isla -Epílogo  -Por la cruz de la espada / Eduardo Castillo  -Evangelio poético / Ángel María Céspedes -El símbolo / Delio Seravile -Brindis / Raimundo Rivas

  16. Hospitalidade Organizacional: Panorama Teórico-Empírico

    Directory of Open Access Journals (Sweden)

    José Alberto Carvalho dos Santos Claro

    2015-10-01

    Full Text Available O objetivo deste texto é o de apresentar as discussões teórico-conceituais sobre Hospitalidade, particularmente a vertente da Hospitalidade Organizacional (HO, que se ocupa das relações hospitaleiras no ambiente do espaço de trabalho. Trata-se de um estudo exploratório, baseado em revisão bibliográfica, seguida de pesquisa de campo por meio de levantamento junto a gestores de pessoas (especialistas ou juízes, sobre o entendimento do tema, visando contribuir para a futura criação de escala de medida para quantificar o grau de HO em uma organização. Como resultado, apresenta-se contribuição teórica para o amadurecimento desta tendência organizacional e indicadores que poderão ser futuramente usados em estudos empíricos e na construção de um instrumento com escala validada para ser utilizada em organizações em qualquer setor de atividade econômica. Palavras-chave: Hospitalidade. Hospitalidade Organizacional. Gestão de Pessoas.Organizational Hospitality: Theorical and Empirical Developments This paper aim is to present the theoretical and conceptual discussions about hospitality, particularly the  Organizational Hospitality (OH, which is concerned with the hospitable relations in the workplace. It’s an exploratory study, based on literature review and field survey with people managers (experts or judges about their understanding about the question. The result indicates that the development of organizational indicators could be used in future empirical studies and to the construction of a validated scale that can be used in any sector of the economic activity. Keywords: Hospitality. Organizational Hospitality. People Management. Indicators.José Alberto Carvalho dos Santos Claro – Doutor. Professor Adjunto da Universidade Federal de São Paulo [UNIFESP], Campus Baixada Santista, Santos, SP. Endereço Lattes http://lattes.cnpq.br/0865792662046289 E-mail: albertoclaro@albertoclaro.pro.br  

  17. Eastward from Africa: palaeocurrent-mediated chameleon dispersal to the Seychelles islands.

    Science.gov (United States)

    Townsend, Ted M; Tolley, Krystal A; Glaw, Frank; Böhme, Wolfgang; Vences, Miguel

    2011-04-23

    Madagascar and the Seychelles are Gondwanan remnants currently isolated in the Indian Ocean. In the Late Cretaceous, these islands were joined with India to form the Indigascar landmass, which itself then split into its three component parts around the start of the Tertiary. This history is reflected in the biota of the Seychelles, which appears to contain examples of both vicariance- and dispersal-mediated divergence from Malagasy or Indian sister taxa. One lineage for which this has been assumed but never thoroughly tested is the Seychellean tiger chameleon, a species assigned to the otherwise Madagascar-endemic genus Calumma. We present a multi-locus phylogenetic study of chameleons, and find that the Seychellean species is actually the sister taxon of a southern African clade and requires accomodation in its own genus as Archaius tigris. Divergence dating and biogeographic analyses indicate an origin by transoceanic dispersal from Africa to the Seychelles in the Eocene-Oligocene, providing, to our knowledge, the first such well-documented example and supporting novel palaeocurrent reconstructions.

  18. Active dispersal in loggerhead sea turtles (Caretta caretta) during the 'lost years'.

    Science.gov (United States)

    Briscoe, D K; Parker, D M; Balazs, G H; Kurita, M; Saito, T; Okamoto, H; Rice, M; Polovina, J J; Crowder, L B

    2016-06-15

    Highly migratory marine species can travel long distances and across entire ocean basins to reach foraging and breeding grounds, yet gaps persist in our knowledge of oceanic dispersal and habitat use. This is especially true for sea turtles, whose complex life history and lengthy pelagic stage present unique conservation challenges. Few studies have explored how these young at-sea turtles navigate their environment, but advancements in satellite technology and numerical models have shown that active and passive movements are used in relation to open ocean features. Here, we provide the first study, to the best of our knowledge, to simultaneously combine a high-resolution physical forcing ocean circulation model with long-term multi-year tracking data of young, trans-oceanic North Pacific loggerhead sea turtles during their 'lost years' at sea. From 2010 to 2014, we compare simulated trajectories of passive transport with empirical data of 1-3 year old turtles released off Japan (29.7-37.5 straight carapace length cm). After several years, the at-sea distribution of simulated current-driven trajectories significantly differed from that of the observed turtle tracks. These results underscore current theories on active dispersal by young oceanic-stage sea turtles and give further weight to hypotheses of juvenile foraging strategies for this species. Such information can also provide critical geographical information for spatially explicit conservation approaches to this endangered population. © 2016 The Author(s).

  19. Management of pest mole crickets in Florida and Puerto Rico with a nematode and parasitic wasp

    International Nuclear Information System (INIS)

    Leppla, N.C.; Frank, J.H.; Adjei, M.B.; Vicente, N.E.

    2007-01-01

    Non-indigenous invasive mole crickets, Scapteriscus vicinus Scudder (Orthoptera: Gryllotalpidae) in Florida and S. didactylus (Latreille) (the 'changa') in Puerto Rico, are being managed with an entomopathogenic nematode, Steinernema scapterisci (Nguyen and Smart) (Rhabditida: Steinernematidae), and a parasitic wasp, Larra bicolor L. (Hymenoptera: Sphecidae). Pest mole cricket populations have declined by 95% in north central Florida since these specialist natural enemies were released and established in the 1980s. Commercial production of the nematode was initiated, nearly 70 billion were applied in 34 Florida counties, and their establishment, spread, and impact on mole crickets were monitored. The infected mole crickets dispersed the nematode rapidly, so that within 6 months these parasites were present in most of the insects trapped in experimental pastures. Three years later, mole cricket populations were reduced to acceptable levels and the bahiagrass had recovered. The nematode was released for the first time in Puerto Rico during 2001 and has persisted; the wasp was introduced in the late 1930s. The geographical distribution of the wasp is being expanded in Florida and Puerto Rico by planting plots of Spermacoce verticillata (L.), a wildflower indigenous to Puerto Rico and widely distributed in southern Florida. Pastures, sod farms, golf courses, landscapes, and vegetable farms in Florida and Puerto Rico are benefiting from biological control of invasive mole crickets. (author) [es

  20. Puerto Rico Above Ground Biomass Map, 2000

    Data.gov (United States)

    U.S. Environmental Protection Agency — This image dataset details the U.S. Commonwealth of Puerto Rico above-ground forest biomass (AGB) (baseline 2000) developed by the United States (US) Environmental...

  1. Puerto Rico ESI/RSI: HABITATS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) and Reach Sensitivity Index (RSI) data for Puerto Rico. ESI data characterize estuarine...

  2. Puerto Rico ESI/RSI: HYDRO (Hydrology)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) and Reach Sensitivity Index (RSI) data for Puerto Rico. ESI data characterize estuarine...

  3. Puerto Rico ESI/RSI: KARST

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) and Reach Sensitivity Index (RSI) data for Puerto Rico. ESI data characterize estuarine...

  4. Puerto Rico Relative Vulnerability to Erosion

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Physical factors, such as the slope of the land, the texture of the soil, and the precipitation regime influence erosion in an area. Parts of Puerto Rico are very...

  5. Puerto Rico ESI/RSI: INDEX

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) and Reach Sensitivity Index (RSI) data for Puerto Rico. ESI data characterize estuarine...

  6. Puerto Rico ESI/RSI: BIRDS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) and Reach Sensitivity Index (RSI) data for Puerto Rico. ESI data characterize estuarine...

  7. Puerto Rico ESI and RSI: WETLANDS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) and Reach Sensitivity Index (RSI) data for Puerto Rico. ESI data characterize estuarine...

  8. Breast Cancer Epidemiology in Puerto Rico

    National Research Council Canada - National Science Library

    Nazario, Cruz M; Freudenheim, Jo

    2008-01-01

    This project has two mayor goals: to design and conduct a pilot case-control breast cancer study among Puerto Rican women, and to train and develop researchers in breast cancer at the University of Puerto Rico...

  9. Estimated Bathymetry of the Puerto Rico shelf

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This classification of estimated depth represents the relative bathymetry of Puerto Rico's shallow waters based on Landsat imagery for NOAA's Coastal Centers for...

  10. Puerto Rico: Information for Status Deliberations

    Science.gov (United States)

    1990-03-01

    Rico has suffered a temporary setback from the destruction caused by Hurricane Hugo , both the availability and quality of the island’s housing stock...34"ý Prnce omi Puerto Rico aw (US li ANTIUDAN (U.S.) ,M S oh’ Montserrat (UK) !tGuadsiffupe (FR.) HONDURAS DOMdINICA Caribbean Sea Rosea q Martinique...Housing (the most recent data available). While the island has suffered a temporary setback because of the destruction caused by Hurricane Hugo

  11. 27 CFR 26.126 - Taxpayment in Puerto Rico.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Taxpayment in Puerto Rico..., DEPARTMENT OF THE TREASURY LIQUORS LIQUORS AND ARTICLES FROM PUERTO RICO AND THE VIRGIN ISLANDS Liquors and Articles Purchased by Tourists in Puerto Rico § 26.126 Taxpayment in Puerto Rico. Liquors upon which all...

  12. Rayleigh wave group-velocity across the Dominican Republic and Puerto Rico from ambient noise tomography

    Science.gov (United States)

    Quiros, D.; Pulliam, J.; Polanco Rivera, E.; Huerfano Moreno, V. A.

    2017-12-01

    The eastern North America-Caribbean (NA-CAR) plate boundary near the islands of Hispaniola (which is comprised of the Dominican Republic and Haiti) and Puerto Rico is a complex transition zone in which strain is accommodated by two transform fault systems and oblique subduction. In 2013, scientists from Baylor University, the Autonomous University of Santo Domingo, and the Puerto Rico Seismic Network deployed 16 broadband stations on the Dominican Republic to expand the local permanent network. The goal of the Greater Antilles Seismic Program (GrASP) is to combine its data with that from permanent networks in Puerto Rico, Haiti, Cuba, the Cayman Islands, and Jamaica to develop a better understanding of the crust and upper mantle structure in the Northeastern Caribbean (Greater Antilles). One important goal of GrASP is to develop robust velocity models that can be used to improve earthquake location and seismic hazard efforts. In this study, we focus on obtaining Rayleigh wave group velocity maps from ambient noise tomography. By cross-correlating ambient seismic noise recorded at 53 stations between 2010 to present, we obtain Green's functions between 1165 pairs of stations. From these, we obtain dispersion curves by the application of FTAN methods with phase-matched filtering. Selection criteria depend on the signal-to-noise ratio and seasonal variability, with further filtering done by rejecting velocities incompatible with maps produced from overdamped tomographic inversions. Preliminary dispersion maps show strong correlations with large-scale geological and tectonic features for periods between 5 - 20 s, such as the Cordillera Central in both the Dominican Republic and Puerto Rico, the Mona Passage, and the NA-CAR subduction zone. Ongoing efforts focus on including shorter periods in Puerto Rico as its denser station distribution could allow us to retrieve higher resolution group velocity maps.

  13. Clock synchronization and dispersion

    International Nuclear Information System (INIS)

    Giovannetti, Vittorio; Lloyd, Seth; Maccone, Lorenzo; Wong, Franco N C

    2002-01-01

    We present a method to defeat effects of dispersion of timing signals when synchronizing clocks. It is based on the recently proposed 'conveyor belt synchronization' scheme and on the quantum dispersion cancellation effect

  14. Dispersing powders in liquids

    CERN Document Server

    Nelson, RD

    1988-01-01

    This book provides powder technologists with laboratory procedures for selecting dispersing agents and preparing stable dispersions that can then be used in particle size characterization instruments. Its broader goal is to introduce industrial chemists and engineers to the phenomena, terminology, physical principles, and chemical considerations involved in preparing and handling dispersions on a commercial scale. The book introduces novices to: - industrial problems due to improper degree of dispersion; - the nomenclature used in describing particles; - the basic physica

  15. Hazardous Waste Cleanup: Thermo King de Puerto Rico Incorporated in Arecibo, Puerto Rico

    Science.gov (United States)

    Thermo King de Puerto Rico, Inc. facility is located in the Zeno Gandia Industrial Area in Arecibo, Puerto Rico. Major features of the facility include six buildings used for manufacturing and storage, a wastewater treatment plant, a hazardous waste and no

  16. Theory of dispersive microlenses

    Science.gov (United States)

    Herman, B.; Gal, George

    1993-01-01

    A dispersive microlens is a miniature optical element which simultaneously focuses and disperses light. Arrays of dispersive mircolenses have potential applications in multicolor focal planes. They have a 100 percent optical fill factor and can focus light down to detectors of diffraction spot size, freeing up areas on the focal plane for on-chip analog signal processing. Use of dispersive microlenses allows inband color separation within a pixel and perfect scene registration. A dual-color separation has the potential for temperature discrimination. We discuss the design of dispersive microlenses and present sample results for efficient designs.

  17. Persistencia del conducto onfalomesentérico

    OpenAIRE

    Mariño, Laura P.; Fraga, Juan I.; Rubio, Soraya; Segarra, Juan; Gaetano, Mauro; Ossés, José A.

    2009-01-01

    La persistencia del conducto onfalomesentérico es una de las formas de presentación más raras de los restos embrionarios derivados de este conducto. Se presenta el caso de un recién nacido en el que se constata salida de contenido intestinal a través del ombligo. Se confirma el diagnóstico de persistencia del conducto onfalomesentérico mediante fistulografía umbilical, procediéndose a su corrección quirúrgica (resección de conducto onfalomesentérico). Se describe la metodología diagnóstica, s...

  18. Thermoluminescence dosimetry in Northwest Puerto Rico

    International Nuclear Information System (INIS)

    Block, A.M.; Clements, R.G.; Rosa, L.I.; Santos, F.

    1975-01-01

    In October, 1973, the Puerto Rico Water Resources Authority sought the initiation of studies aimed at determining background radiological characteristics of the northwestern quadrant of Puerto Rico using thermoluminescent dosemeters. Some of the studies were required for supporting data for the environmental report submitted as part of the licensing procedure in the establishment of thermonuclear electric power generation facilities in Barrio Islote, Arecibo, Puerto Rico. Previous studies of radiological characteristics of the area had been made using sodium iodide sensing equipment in an airplane flying at an altitude of 500 ft. The results are expressed in counts per second, and provide useful comparative levels for radioactivity measured with the thermoluminescent detectors. (U.S.)

  19. Delphinid systematics and biogeography with a focus on the current genus Lagenorhynchus: Multiple pathways for antitropical and trans-oceanic radiation

    KAUST Repository

    Banguera Hinestroza, Eulalia

    2014-11-01

    The six species currently classified within the genus Lagenorhynchus exhibit a pattern of antitropical distribution common among marine taxa. In spite of their morphological similarities they are now considered an artificial grouping, and include both recent and the oldest representatives of the Delphinidae radiation. They are, therefore, a good model for studying questions about the evolutionary processes that have driven dolphin speciation, dispersion and distribution. Here we used two different approaches. First we constructed a multigenic phylogeny with a minimum amount of missing data (based on 9 genes, 11,030 bp, using the 6 species of the genus and their closest relatives) to infer their relationships. Second, we built a supermatrix phylogeny (based on 33 species and 27 genes) to test the effect of taxon sampling on the phylogeny of the genus, to provide inference on biogeographic history, and provide inference on the main events shaping the dispersion and radiation of delphinids. Our analyses suggested an early evolutionary history of marine dolphins in the North Atlantic Ocean and revealed multiple pathways of migration and radiation, probably guided by paleoceanographic changes during the Miocene and Pliocene. L. acutus and L albirostris likely shared a common ancestor that arose in the North Atlantic around the Middle Miocene, predating the radiation of subfamilies Delphininae, Globicephalinae and Lissodelphininae. (C) 2014 Elsevier Inc. All rights reserved.

  20. Plasma rico en plaquetas vs. plasma rico en factores de crecimiento

    OpenAIRE

    Carrasco Luna, Joaquín; Bonete Lluch, D.; Gomar Sancho, Francisco

    2009-01-01

    El desarrollo de los preparados plasmáticos ha generado grandes expectativas en la reparación ósea y han alcanzado gran desarrollo comercial de los kits de obtención del Plasma Rico en Plaquetas (PRP), también conocido como concentrado rico en plaquetas (PRC), gel de plaquetas autólogo, y plasma rico en factores de crecimiento (PRF) y su efecto sobre la regeneración esquelética. La generación de concentrados plasmáticos de plaquetas tiene como objetivo la liberación de factores de...

  1. Sex Differences and Depression in Puerto Rico.

    Science.gov (United States)

    Canino, Glorisa J.; And Others

    1987-01-01

    Examined sex differences in rates of depressive disorders and depressive symptomatology, as measured by the Diagnostic Interview Schedule, for an island-wide probability sample of Puerto Rico. Found depression significantly more prevalent among women than men. Discusses risk factors from a sex-role and cultural perspective. (Author/KS)

  2. Island in Crisis: Response to Puerto Rico

    Science.gov (United States)

    Zenere, Frank J.

    2018-01-01

    On September 6, 2017, Hurricane Irma, a Category 5 storm packing winds of 185 miles per hour skirted the northern coast of Puerto Rico, leaving 1 million residents without electrical power. Schools were closed for 5 days, but a major calamity was narrowly avoided. Overall, residents were grateful for their good fortune, but the same could not be…

  3. Tortuguero Bay [Puerto Rico] environmental studies

    International Nuclear Information System (INIS)

    Wood, E.D.; Youngbluth, M.J.; Nutt, M.E.; Yoshioka, P.; Canoy, M.J.

    1975-01-01

    Site selection surveys and environmental research studies of seven coastal sites in Puerto Rico for construction of power generating facilities were carried out. Data are presented on the physical, chemical, and geological parameters of the Tortuguero Bay site, and the ecological parameters of zooplankton, benthic invertebrates, plant and fish communities. (U.S.)

  4. Areas naturales protegidas de Puerto Rico

    Science.gov (United States)

    William A. Gould; Maya Quinones; Mariano Solórzano; Waldemar Alcobas; Caryl Alarcon

    2011-01-01

    En este mapa mostramos las areas naturales protegidas designadas para la conservacion de los recursos naturales en Puerto Rico y regiones reguladas por ley con el potencial de mejorar la conservacion de los mismos. La designacion de areas protegidas es un proceso dinamico debido a que es el resultado de la constante evolucion de valores en los diferentes sectores de la...

  5. Lichens in Puerto Rico: an ecosystem approach

    Science.gov (United States)

    Joel A. Mercado-Díaz; William A. Gould; Grizelle Gonzalez; Robert. Lücking

    2015-01-01

    This work presents basic information on tropical lichenology. It also describes general aspects about the ecology and biodiversity of these organisms in eight forest ecosystems present along an elevational gradient in northeastern Puerto Rico. These ecosystems consist of elfin woodlands, palo colorado, sierra palm, tabonuco, lowland moist, dry, mangrove, and...

  6. A Chronological History of Puerto Rico.

    Science.gov (United States)

    Tovar, Federico Ribes

    This book presents a chronological history of Puerto Rico from prehistory and discovery through December of 1972. It includes information on the persons and events that influenced the course of Puerto Rican history. A table of contents and a selective index are included. (Author/AM)

  7. U.S. Wood Shipments to Puerty Rico

    Science.gov (United States)

    James E. Granskog

    1992-01-01

    Puerto Rico's importance as an offshore market for U.S. wood products is often overlooked. Because of its unique Commonwealth status, trade flows between the United States and Puerto Rico are recorded separately and are not counted in the U.S. foreign trade statistics. In 1991, wood product shipments from the United States to Puerto Rico totaled more than $83...

  8. Dispersal of forest insects

    Science.gov (United States)

    Mcmanus, M. L.

    1979-01-01

    Dispersal flights of selected species of forest insects which are associated with periodic outbreaks of pests that occur over large contiguous forested areas are discussed. Gypsy moths, spruce budworms, and forest tent caterpillars were studied for their massive migrations in forested areas. Results indicate that large dispersals into forested areas are due to the females, except in the case of the gypsy moth.

  9. Improved new generation dispersants

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    The use of dispersants to combat oil spills has attracted controversy over the years, and there has been a number of accusations of the chemicals involved doing more harm than good. A new study by the International Petroleum Industry Environmental Conservation Association discusses the positive and the negatives of dispersant use to be considered when drawing up spill contingency plans. (author)

  10. Seed dispersal in fens

    Science.gov (United States)

    Middleton, B.; Van Diggelen, R.; Jensen, K.

    2006-01-01

    Question: How does seed dispersal reduce fen isolation and contribute to biodiversity? Location: European and North American fens. Methods: This paper reviews the literature on seed dispersal to fens. Results: Landscape fragmentation may reduce dispersal opportunities thereby isolating fens and reducing genetic exchange. Species in fragmented wetlands may have lower reproductive success, which can lead to biodiversity loss. While fens may have always been relatively isolated from each other, they have become increasingly fragmented in modern times within agricultural and urban landscapes in both Europe and North America. Dispersal by water, animals and wind has been hampered by changes related to development in landscapes surrounding fens. Because the seeds of certain species are long-lived in the seed bank, frequent episodes of dispersal are not always necessary to maintain the biodiversity of fens. However, of particular concern to restoration is that some dominant species, such as the tussock sedge Carex stricta, may not disperse readily between fens. Conclusions: Knowledge of seed dispersal can be used to maintain and restore the biodiversity of fens in fragmented landscapes. Given that development has fragmented landscapes and that this situation is not likely to change, the dispersal of seeds might be enhanced by moving hay or cattle from fens to damaged sites, or by reestablishing lost hydrological connections. ?? IAVS; Opulus Press.

  11. Dispersal and metapopulation stability

    Directory of Open Access Journals (Sweden)

    Shaopeng Wang

    2015-10-01

    Full Text Available Metapopulation dynamics are jointly regulated by local and spatial factors. These factors may affect the dynamics of local populations and of the entire metapopulation differently. Previous studies have shown that dispersal can stabilize local populations; however, as dispersal also tends to increase spatial synchrony, its net effect on metapopulation stability has been controversial. Here we present a simple metapopulation model to study how dispersal, in interaction with other spatial and local processes, affects the temporal variability of metapopulations in a stochastic environment. Our results show that in homogeneous metapopulations, the local stabilizing and spatial synchronizing effects of dispersal cancel each other out, such that dispersal has no effect on metapopulation variability. This result is robust to moderate heterogeneities in local and spatial parameters. When local and spatial dynamics exhibit high heterogeneities, however, dispersal can either stabilize or destabilize metapopulation dynamics through various mechanisms. Our findings have important theoretical and practical implications. We show that dispersal functions as a form of spatial intraspecific mutualism in metapopulation dynamics and that its effect on metapopulation stability is opposite to that of interspecific competition on local community stability. Our results also suggest that conservation corridors should be designed with appreciation of spatial heterogeneities in population dynamics in order to maximize metapopulation stability.

  12. Gondwanian relicts and oceanic dispersal in a cosmopolitan radiation of euedaphic ground beetles.

    Science.gov (United States)

    Andújar, Carmelo; Faille, Arnaud; Pérez-González, Sergio; Zaballos, Juan P; Vogler, Alfried P; Ribera, Ignacio

    2016-06-01

    Anillini are a tribe of minute, euedaphic ground beetles (Carabidae) characterized by the loss of eyes, loss of wings and high levels of local endemism. Despite their presumed low dispersal, they have a nearly cosmopolitan distribution, including isolated islands such as New Zealand and New Caledonia. We used a time calibrated molecular phylogeny to test, first, if the tribe as currently understood is monophyletic and, second, whether the time of divergence is compatible with an early vicariant diversification after the breakup of Gondwana. We sequenced portions of 6 mitochondrial and 3 nuclear genes for 66 specimens in 17 genera of Anillini plus 39 outgroups. The resulting phylogenetic tree was used to estimate the time of diversification using two independent calibration schemes, by applying molecular rates for the related genus Carabus or by dating the tree with fossil and geological information. Rates of molecular evolution and lineage ages were mostly concordant between both calibration schemes. The monophyly of Anillini was well-supported, and its age was consistent with a Gondwanian origin of the main lineages and an initial diversification at ca. 100Ma representing the split between the eyed Nesamblyops (New Zealand) and the remaining Anillini. The subsequent diversification, including the split of the Nearctic Anillinus and the subsequent splits of Palaearctic lineages, was dated to between 80 and 100Ma and thus was also compatible with a tectonic vicariant origin. On the contrary, the estimated age of the New Caledonian blind Orthotyphlus at ca. 30±20Ma was incompatible with a vicariant origin, suggesting the possibility of trans-oceanic dispersal in these endogean beetles. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Proteome analysis of the hypercholestrolemic rat, RICO

    International Nuclear Information System (INIS)

    Cho, S.Y.; Park, K.-S.; Paik, Y.-K.; Seong, J.-K.

    2001-01-01

    In an attempt to develop novel markers for hypercholesterolemia, hepatic tissues and serum prepared from hypeicholesterolemic rat (i e RICO) were analyzed by two-dimensional electrophoresis (2DE) and matrix-assisted laser desorption ionization mass spectrometry (MALDI-ToF). Results were compared to those of paired inbreed rat (WKY). Comparative analysis of the respective spot patterns in 2DE revealed that the numbers of differential expression proteins were identified in serum and liver tissues of RICO. Some of the representative proteins annotated in 2DE were apolipoprotein family and numerous lipid metabolism related proteins. Especially, we found that protein disulfide isomerase subunits (ER-60) in 2DE have differential post-translational modification pattern by MALDI-ToF analysis. Our results suggest that the proteomic analysis of these proteins might be a novel approach to identify the molecular events in detail during lipid disorder such atherosclerosis

  14. Breast Cancer Epidemiology in Puerto Rico

    Science.gov (United States)

    2014-08-01

    Preparándonos para vencer: Programa para identificar las necesidades de información y apoyo para las mujeres sobrevivientes de cáncer de mama...of recruitment. Controls were identified from participants in the Estudio Continuo de Salud (ECS), a National Health Survey in Puerto Rico, which was...menopausal at interview, as expected by the age criteria for inclusion . Eighty eight percent (88%) of the participants had their first pregnancy before age

  15. Aves municipales oficiales de Puerto Rico

    Science.gov (United States)

    Carlos M. Domínguez Cristóbal

    2009-01-01

    Las aves constituyen uno de los recursos de muy poco uso como símbolo oficial representativo de los municipios en Puerto Rico. Es muy probable que la decisión que màs pueda influenciar en esa selección esté relacionada con la movilidad de las aves ya que éstas no se limitan a una municipalidad en específico...

  16. Sand and gravel resources of Puerto Rico

    Science.gov (United States)

    Rodriguez, Rafael W.

    Many of Puerto Rico's beaches are eroding, and though rates of erosion vary, it is a major concern for the tourism and residential development industries. More than 85 percent of the population lives within 7 kilometers of the coast and they are heavily dependent on tourists that are attracted by the island's beaches and coral reefs. High-quality scientific data are needed to help formulate public policy regarding residential and commercial construction along the coast, beach replenishment, and future use of marine resources. Scientists have long recognized that the causes of coastal land loss are not limited to a relative rise in sea level, but can be manmade as well. For example, sediment supply to beaches especially along the north shore of Puerto Rico has been strongly affected by upstream river channeling, dam construction, various agricultural practices, paving and urbanization, as well as shallow-water oceanographic processes. The response to coastal erosion in Puerto Rico has been mostly crisis based leading to engineered solutions that have a negative effect on the coastal environment.

  17. A costal dispersion model

    International Nuclear Information System (INIS)

    Rahm, L.; Nyberg, L.; Gidhagen, L.

    1990-01-01

    A dispersion model to be used off costal waters has been developed. The model has been applied to describe the migration of radionuclides in the Baltic sea. A summary of the results is presented here. (K.A.E)

  18. Wave-equation dispersion inversion

    KAUST Repository

    Li, Jing; Feng, Zongcai; Schuster, Gerard T.

    2016-01-01

    We present the theory for wave-equation inversion of dispersion curves, where the misfit function is the sum of the squared differences between the wavenumbers along the predicted and observed dispersion curves. The dispersion curves are obtained

  19. Reactimeter dispersion equation

    OpenAIRE

    A.G. Yuferov

    2016-01-01

    The aim of this work is to derive and analyze a reactimeter metrological model in the form of the dispersion equation which connects reactimeter input/output signal dispersions with superimposed random noise at the inlet. It is proposed to standardize the reactimeter equation form, presenting the main reactimeter computing unit by a convolution equation. Hence, the reactimeter metrological characteristics are completely determined by this unit hardware function which represents a transient re...

  20. Fickian dispersion is anomalous

    Science.gov (United States)

    Cushman, John H.; O'Malley, Dan

    2015-12-01

    The thesis put forward here is that the occurrence of Fickian dispersion in geophysical settings is a rare event and consequently should be labeled as anomalous. What people classically call anomalous is really the norm. In a Lagrangian setting, a process with mean square displacement which is proportional to time is generally labeled as Fickian dispersion. With a number of counter examples we show why this definition is fraught with difficulty. In a related discussion, we show an infinite second moment does not necessarily imply the process is super dispersive. By employing a rigorous mathematical definition of Fickian dispersion we illustrate why it is so hard to find a Fickian process. We go on to employ a number of renormalization group approaches to classify non-Fickian dispersive behavior. Scaling laws for the probability density function for a dispersive process, the distribution for the first passage times, the mean first passage time, and the finite-size Lyapunov exponent are presented for fixed points of both deterministic and stochastic renormalization group operators. The fixed points of the renormalization group operators are p-self-similar processes. A generalized renormalization group operator is introduced whose fixed points form a set of generalized self-similar processes. Power-law clocks are introduced to examine multi-scaling behavior. Several examples of these ideas are presented and discussed.

  1. The green areas of San Juan, Puerto Rico

    Directory of Open Access Journals (Sweden)

    Olga M. Ramos-González

    2014-09-01

    Full Text Available Green areas, also known as green infrastructure or urban vegetation, are vital to urbanites for their critical roles in mitigating urban heat island effects and climate change and for their provision of multiple ecosystem services and aesthetics. Here, I provide a high spatial resolution snapshot of the green cover distribution of the city of San Juan, Puerto Rico, by incorporating the use of morphological spatial pattern analysis (MSPA as a tool to describe the spatial pattern and connectivity of the city's urban green areas. Analysis of a previously developed IKONOS 4-m spatial resolution classification of the city of San Juan from 2002 revealed a larger area of vegetation (green areas or green infrastructure than previously estimated by moderate spatial resolution imagery. The city as a whole had approximately 42% green cover and 55% impervious surfaces. Although the city appeared greener in its southern upland sector compared to the northern coastal section, where most built-up urban areas occurred (66% impervious surfaces, northern San Juan had 677 ha more green area cover dispersed across the city than the southern component. MSPA revealed that most forest cover occurred as edges and cores, and green areas were most commonly forest cores, with larger predominance in the southern sector of the municipality. In dense, built-up, urban land, most of the green areas occurred in private yards as islets. When compared to other cities across the United States, San Juan was most similar in green cover features to Boston, Massachusetts, and Miami, Florida. Per capita green space for San Juan (122.2 m²/inhabitant was also comparable to these two U.S. cities. This study explores the intra-urban vegetation variation in the city of San Juan, which is generally overlooked by moderate spatial resolution classifications in Puerto Rico. It serves as a starting point for green infrastructure mapping and landscape pattern analysis of the urban green spaces

  2. Coping with power dispersion?

    DEFF Research Database (Denmark)

    2014-01-01

    The last decades have witnessed a significant shift in policy competences away from central governments in Europe. The reallocation of competences spans over three dimensions: upwards; sideways; and downwards. This collection takes the dispersion of powers as a starting point and seeks to assess...... how the actors involved cope with the new configurations. In this introduction, we discuss the conceptualization of power dispersion and highlight the ways in which the contributions add to this research agenda. We then outline some general conclusions and end by indicating future avenues of research....... Taken together, the collection contributes some answers to the challenge of defining and measuring – in a comparative way – the control and co-ordination mechanisms which power dispersion generates. It also explores the tension between political actors' quest for autonomy and the acknowledgement...

  3. 26 CFR 1.1402(a)-9 - Puerto Rico.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 12 2010-04-01 2010-04-01 false Puerto Rico. 1.1402(a)-9 Section 1.1402(a)-9...) INCOME TAXES Tax on Self-Employment Income § 1.1402(a)-9 Puerto Rico. (a) Residents. A resident of Puerto... alien, a citizen of the United States, or a citizen of Puerto Rico, shall compute his net earnings from...

  4. Plasma rico en plaquetas Platelet -rich plasma

    OpenAIRE

    J. González Lagunas

    2006-01-01

    El Plasma Rico en Plaquetas es una suspensión concentrada de la sangre centrifugada que contiene elevadas concentraciones de trombocitos. Durante los últimos años, este producto ha aparecido de forma repetida en publicaciones científicas y en medios de comunicación generales como un producto que por sus características induce la curación y regeneración de los tejidos. La premisa de su uso es que las elevadas concentraciones de plaquetas en el PRP, liberan cantidades significativas de factores...

  5. Plasma rico em plaquetas na Implantologia

    OpenAIRE

    Rego, Luis André Ferreira Lopes

    2014-01-01

    Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária As reabilitações orais implanto-suportadas resolveram grandes limitações das próteses removíveis convencionais. No entanto, o tempo de espera e o sucesso no tratamento com implantes trouxeram novos desafios, tal como o uso de concentrados autólogos de plaquetas para promoção da osteointegração. O plasma rico em plaquetas é definido c...

  6. histórico da tecnologia

    Directory of Open Access Journals (Sweden)

    Marcos Cezar de Freitas

    2006-01-01

    Full Text Available Este artículo analiza la contribución de Álvaro Vieira Pinto para los estudios de economía y educación. Su concepto de trabajo tecnológicamente elaborado puede ser reconocido como resultado de una profunda investigación sobre las relaciones humanas que encontramos en la “cultura de la economía”. Su camino teórico hasta los escritos de Marx, muestran una capacidad erudita de relacionar educación y emancipación política con la historia de la tecnología.

  7. Burden of stroke in Puerto Rico.

    Science.gov (United States)

    Zevallos, Juan; Santiago, Fernando; González, Juan; Rodríguez, Abiezer; Pericchi, Luis; Rodríguez-Mercado, Rafael; Nobo, Ulises

    2015-01-01

    Stroke is the fifth leading cause of death and the first cause of long-term disability in Puerto Rico. Trained staff reviewed and independently validated the medical records of patients who had been hospitalized with possible stroke at any of the 20 largest hospitals located in Puerto Rico during 2007, 2009, and 2011. The mean age of the 5005 newly diagnosed stroke patients (51·2% female) was 70 years. At the time of hospitalization, women were 4½ years older, were less likely to be married (60·2% vs. 39·9%, P diabetes (56·0% vs. 54·8%), hypertension (89·1% vs. 85·0%), and low density lipoprotein-cholesterol (LDL-Chol) > 100 mg/dL (65·7% vs. 57·5%) P < 0·05. Ischemic stroke represented 75% of all types of strokes. Atrial fibrillation was mentioned in 7·9% of the medical records. The risk for dying before discharge was similar for both genders, but was 40% higher for women than for men at one-year follow-up: age-adjusted odds ratio = 1·4 (95% confidence interval = 1·2-1·5). © 2014 World Stroke Organization.

  8. Estimated water use in Puerto Rico, 2010

    Science.gov (United States)

    Molina-Rivera, Wanda L.

    2014-01-01

    Water-use data were aggregated for the 78 municipios of the Commonwealth of Puerto Rico for 2010. Five major offstream categories were considered: public-supply water withdrawals and deliveries, domestic and industrial self-supplied water use, crop-irrigation water use, and thermoelectric-power freshwater use. One instream water-use category also was compiled: power-generation instream water use (thermoelectric saline withdrawals and hydroelectric power). Freshwater withdrawals for offstream use from surface-water [606 million gallons per day (Mgal/d)] and groundwater (118 Mgal/d) sources in Puerto Rico were estimated at 724 million gallons per day. The largest amount of freshwater withdrawn was by public-supply water facilities estimated at 677 Mgal/d. Public-supply domestic water use was estimated at 206 Mgal/d. Fresh groundwater withdrawals by domestic self-supplied users were estimated at 2.41 Mgal/d. Industrial self-supplied withdrawals were estimated at 4.30 Mgal/d. Withdrawals for crop irrigation purposes were estimated at 38.2 Mgal/d, or approximately 5 percent of all offstream freshwater withdrawals. Instream freshwater withdrawals by hydroelectric facilities were estimated at 556 Mgal/d and saline instream surface-water withdrawals for cooling purposes by thermoelectric-power facilities was estimated at 2,262 Mgal/d.

  9. Interface, a dispersed architecture

    NARCIS (Netherlands)

    Vissers, C.A.

    1976-01-01

    Past and current specification techniques use timing diagrams and written text to describe the phenomenology of an interface. This paper treats an interface as the architecture of a number of processes, which are dispersed over the related system parts and the message path. This approach yields a

  10. Psychorheology of food dispersions

    Czech Academy of Sciences Publication Activity Database

    Štern, Petr; Panovská, Z.; Pokorný, J.

    2010-01-01

    Roč. 58, č. 1 (2010), s. 29-35 ISSN 0042-790X R&D Projects: GA AV ČR IAA2060404 Institutional research plan: CEZ:AV0Z20600510 Keywords : psychorheology * food dispersions * tomato ketchup * rheology * sensory analysis Subject RIV: BK - Fluid Dynamics Impact factor: 0.553, year: 2010

  11. Dispersal of sticky particles

    Science.gov (United States)

    Reddy, Ramana; Kumar, Sanjeev

    2007-12-01

    In this paper, we show through simulations that when sticky particles are broken continually, particles are dispersed into fine dust only if they are present in a narrow range of volume fractions. The upper limit of this range is 0.20 in the 2D and 0.10 in the 3D space. An increase in the dimensionality of space reduces the upper limit nearly by a factor of two. This scaling holds for dispersal of particles in hyperdimensional space of dimensions up to ten, the maximum dimension studied in this work. The maximum values of volume fractions obtained are significantly lower than those required for close packing and random packing of discs in 2D and spheres in 3D space. These values are also smaller than those required for critical phenomena of cluster percolation. The results obtained are attributed to merger cascades of sticky particles, triggered by breakup events. A simple theory that incorporates this cascade is developed to quantitatively explain the observed scaling of the upper limit with the dimensionality of space. The theory also captures the dynamics of the dispersal process in the corresponding range of particle volume fractions. The theory suggests that cascades of order one and two predominantly decide the upper limit for complete dispersal of particles.

  12. SEMBLANZA DEL PROFESOR EDMUNDO RICO "1897 - 1967"

    Directory of Open Access Journals (Sweden)

    Alfonso Agusti Pastor

    1981-10-01

    Full Text Available

    Finalizaba el año de 1925 cuando un jurado, reunido en los viejos claustros de Santa Inés, otorgaba a EDMUNDO RICO el grado de Doctor en Medicina y Cirugía. Ese jurado examinador integrado por los profesionales más destacados de la época y presidido por el Profesor José María Lombana Barreneche, estaba constituido por los profesores Carios Esguerra, Roberto Franco, Luis Felipe Calderón y Juan N. Corpas, siendo Secretario de la Facultad el entonces muy joven médico José del Carmen Acosta. Es de anotar que los hombres mencionados llenan todo un periodo médico en 10 que va corrido del presente siglo.

    La tesis del graduado versaba sobre la patogenia y tratamiento de la rabia y en ella exhibía ya el novel galeno su estilo inconfundible, por ser tan personal; esa tesis todavía tiene actualidad y en ella se describe, como en una novela de suspenso, la carrera a muerte que se entabla a través del sistema nervioso, entre el virus de la hidrofobia y las antitoxinas
    correspondientes, siendo la meta de la carrera los centros nerviosos superiores. No es de extrañar que ya Rico exhibiera veteranía en su amena prosa, si siendo estudiante había escrito numerosas siluetas sobre varios profesores y había colaborado ocasionalmente en la prensa periódica.
    Estaba en vigencia en aquéllos tiempos la antigua y gallarda usanza de respetar, acatar y estimar a los profesores de la Facultad. Y en verdad que Rico siempre fue fiel a tal postulado de elemental hidalguía, a pesar de ser un hombre esencialmente irreverente. Eran los tiempos en que a la muerte del Profesor Rivas, su cadáver fue transportado en hombros por sus alumnos reprobados.
    Regían por entonces los principios de la medicina francesa, a la sazón a la cabeza de la ciencia universal, y por tanto Rico fue a perfeccionar sus estudios a la antigua Lutecia. Alli al comienzo siguió cursillos de cirugía, abandonándolos prestamente para dedicarse a las ciencias psicol

  13. 33 CFR 165.755 - Safety Zone; Guayanilla, Puerto Rico

    Science.gov (United States)

    2010-07-01

    ... Zone; Guayanilla, Puerto Rico (a) The following area is established as a safety zone during the... the Eco-Electrica waterfront facility in Guayanilla Bay, Puerto Rico. The safety zone remains in... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety Zone; Guayanilla, Puerto...

  14. 78 FR 3495 - Puerto Rico Disaster #PR-00017

    Science.gov (United States)

    2013-01-16

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 13437 and 13438] Puerto Rico Disaster PR-00017 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster for the Commonwealth of Puerto Rico Dated 01/03/2013. Incident: Heavy...

  15. 75 FR 39060 - Puerto Rico Disaster #PR-00009

    Science.gov (United States)

    2010-07-07

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12214 and 12215] Puerto Rico Disaster PR-00009 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the Commonwealth of Puerto Rico (FEMA-1919-DR...

  16. 76 FR 55155 - Puerto Rico Disaster #PR-00014

    Science.gov (United States)

    2011-09-06

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12768 and 12769] Puerto Rico Disaster PR-00014 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for the Commonwealth of Puerto Rico (FEMA-4017-DR), dated 08/ 27/2011...

  17. 76 FR 67244 - Puerto Rico Disaster Number PR-00014

    Science.gov (United States)

    2011-10-31

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12768 and 12769] Puerto Rico Disaster Number PR-00014 AGENCY: U.S. Small Business Administration. ACTION: Amendment 5. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for the Commonwealth of Puerto Rico (FEMA-4017...

  18. 75 FR 51294 - Puerto Rico Disaster # PR-00010

    Science.gov (United States)

    2010-08-19

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12270 and 12271] Puerto Rico Disaster PR-00010 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster for the Commonwealth of PUERTO RICO dated 08/11/2010. Incident: Severe...

  19. 76 FR 59179 - Puerto Rico Disaster Number PR-00014

    Science.gov (United States)

    2011-09-23

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12768 and 12769] Puerto Rico Disaster Number PR-00014 AGENCY: U.S. Small Business Administration. ACTION: Amendment 2. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for the Commonwealth of Puerto Rico (FEMA-4017...

  20. 75 FR 69733 - Puerto Rico Disaster #PR-00012

    Science.gov (United States)

    2010-11-15

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12368 and 12369] Puerto Rico Disaster PR-00012 AGENCY: U.S. Small Business Administration. ACTION: Amendment 1. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the Commonwealth of Puerto Rico...

  1. 75 FR 68394 - Puerto Rico Disaster # PR-00012

    Science.gov (United States)

    2010-11-05

    ... SMALL BUSINESS ADMINISTRATION Disaster Declaration 12368 and 12369 Puerto Rico Disaster PR-00012 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the Commonwealth of Puerto Rico (FEMA--1946--DR...

  2. 78 FR 4966 - Puerto Rico Disaster #PR-00018

    Science.gov (United States)

    2013-01-23

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 13445 and 13446] Puerto Rico Disaster PR-00018 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster for the Commonwealth of Puerto Rico dated 01/10/2013. Incident: Tropical...

  3. 76 FR 55154 - Puerto Rico Disaster #PR-00015

    Science.gov (United States)

    2011-09-06

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12770 and 12771] Puerto Rico Disaster PR-00015 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the Commonwealth of Puerto Rico (FEMA-4017-DR...

  4. 76 FR 56858 - Puerto Rico Disaster Number PR-00014

    Science.gov (United States)

    2011-09-14

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12768 and 12769] Puerto Rico Disaster Number PR-00014 AGENCY: U.S. Small Business Administration. ACTION: Amendment 1. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for the Commonwealth of Puerto Rico (FEMA-4017...

  5. 76 FR 44647 - Puerto Rico Disaster #PR-00013

    Science.gov (United States)

    2011-07-26

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12699 and 12700] Puerto Rico Disaster PR-00013 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the Commonwealth of Puerto Rico (FEMA-4004-DR...

  6. 76 FR 66768 - Puerto Rico Disaster #PR-00016

    Science.gov (United States)

    2011-10-27

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12897 and 12898] Puerto Rico Disaster PR-00016 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for the Commonwealth of Puerto Rico (FEMA-4040-DR), dated 10/ 18/2011...

  7. 75 FR 2165 - Puerto Rico Disaster No. PR-00007

    Science.gov (United States)

    2010-01-14

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration Nos. 12004 and 12005; Puerto Rico Disaster No. PR-00007] Puerto Rico Disaster No. PR-00007 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster for the Commonwealth of...

  8. Uso de terreno urbano y rural en Puerto Rico

    Science.gov (United States)

    Sebastian Martinuzzi; William A. Gould; Olga M. Ramos Gonzalez; Maya Quinones; Michael E. Jimenez

    2008-01-01

    El Proyecto de Analisis de Gap de Puerto Rico (PRGAP) (Gould et al. 2008) desarrollo tres usos de terrenos para Puerto Rico: Urbano, Suburbano, y Rural (Martinuzzi et al. 2007). Estas regiones tambien pueden ser consideradas como urbano, densamente-poblado rural, y escasamente-poblado rural, o como urbano y area silvestre con una interfase de area silvestre-urbana. La...

  9. Characterization of the Network of Protected Areas in Puerto Rico

    Science.gov (United States)

    J. Castro-Prieto; Maya Quinones; William Gould

    2016-01-01

    Our goal was to describe the biodiversity and associated landscape diversity and forest cover characteristics within the network of terrestrial protected areas in Puerto Rico. We conducted spatial analysis to quantify different indicators of diversity at these sites. We found that protected areas in Puerto Rico overlap the most species-rich regions on the island,...

  10. 29 CFR 510.20 - Wage surveys in Puerto Rico.

    Science.gov (United States)

    2010-07-01

    ... IMPLEMENTATION OF THE MINIMUM WAGE PROVISIONS OF THE 1989 AMENDMENTS TO THE FAIR LABOR STANDARDS ACT IN PUERTO... qualify for an extended minimum wage phase-in, the government of Puerto Rico would be required to furnish... 29 Labor 3 2010-07-01 2010-07-01 false Wage surveys in Puerto Rico. 510.20 Section 510.20 Labor...

  11. Analisis espacial de las areas protegidas terrestres de Puerto Rico

    Science.gov (United States)

    M. Quinones; W.A. Gould; J. Castro-Prieto; S. Martinuzzi

    2013-01-01

    En este mapa de investigacion describimos las areas protegidas terrestres de Puerto Rico basado en elementos naturales y antropogenicos del paisaje. Utilizamos datos geoespaciales para calcular la extension y representatividad de elementos del paisaje dentro de las areas protegidas de Puerto Rico, i.e., cobertura del terreno (Gould et al. 2007), asentamientos urbanos...

  12. Dispersed flow film boiling

    International Nuclear Information System (INIS)

    Andreani, M.; Yadigaroglu, G.

    1989-12-01

    Dispersed flow film boiling is the heat transfer regime that occurs at high void fractions in a heated channel. The way this transfer mode is modelled in the NRC computer codes (RELAP5 and TRAC) and the validity of the assumption and empirical correlations used is discussed. An extensive review of the theoretical and experimental work related with heat transfer to highly dispersed mixtures reveals the basic deficiencies of these models: the investigation refers mostly to the typical conditions of low rate bottom reflooding, since the simulation of this physical situation by the computer codes has often showed poor results. The alternative models that are available in the literature are reviewed, and their merits and limits are highlighted. The modification that could improve the physics of the models implemented in the codes are identified. (author) 13 figs., 123 refs

  13. Working document dispersion models

    International Nuclear Information System (INIS)

    Dop, H. van

    1988-01-01

    This report is a summary of the most important results from June 1985 of the collaboration of the RIVM (Dutch National Institute for Public Health and Environment Hygiene) and KNMI (Royal Dutch Meteorologic Institute) on the domain of dispersion models. It contains a short description of the actual SO x /NO x -model. Furthermore it contains recommendations for modifications of some numerical-mathematical aspects and an impulse to a more complete description of chemical processes in the atmosphere and the (wet) deposition process. A separate chapter is devoted to the preparation of meteorologic data which are relevant for dispersion as well as atmospheric chemistry and deposition. This report serves as working document for the final formulation of a acidifying- and oxidant-model. (H.W.). 69 refs.; 51 figs.; 13 tabs.; 3 schemes

  14. Spatially Dispersed Employee Recovery

    DEFF Research Database (Denmark)

    Hvass, Kristian Anders; Torfadóttir, Embla

    2014-01-01

    Employee recovery addresses either employee well-being or management's practices in aiding employees in recovering themselves following a service failure. This paper surveys the cabin crew at a small, European, low-cost carrier and investigates employees' perceptions of management practices to aid...... personnel achieve service recovery. Employee recovery within service research often focuses on front-line employees that work in a fixed location, however a contribution to the field is made by investigating the recovery of spatially dispersed personnel, such as operational personnel in the transport sector......, who have a work place away from a fixed or central location and have minimal management contact. Results suggest that the support employees receive from management, such as recognition, information sharing, training, and strategic awareness are all important for spatially dispersed front...

  15. Heat dispersion in rivers

    International Nuclear Information System (INIS)

    Shaw, T.L.

    1974-01-01

    One of the tasks of the Sonderforschungsbereich 80 is to study the dispersion of heat discharged into rivers and other bodies of water and to develop methods which permit prediction of detrimental effects caused by the heated discharges. In order to help the SFB 80 to specify this task, Dr. Shaw, lecturer of Civil Engineering at the Bristol University, conducted a literature survey on heat-dispersion studies during the two months which he spent as a visiting research fellow with the SFB 80 at the University of Karlsruhe in the summer of 1973. The following report is the outcome of this survey. It gives Dr. Shaw's assessment of the present state of knowledge - based almost exclusively on literature in the English language - and compares this with the knowledge required by river planners. The apparent discrepancy leads to suggestions for future research. Selected references as well as a representative bibliography can be found at the end of the report. (orig.) [de

  16. The Red Atlantic: Transoceanic Cultural Exchanges

    Science.gov (United States)

    Weaver, Jace

    2011-01-01

    The development of David Armitage's "white Atlantic" history parallels the Cold War origins of American studies with its mission to define and promote "American culture" or "American civilization." British scholar Paul Gilroy's "The Black Atlantic" served as a necessary corrective. Armitage's statement leads…

  17. Taylor dispersion of nanoparticles

    Science.gov (United States)

    Balog, Sandor; Urban, Dominic A.; Milosevic, Ana M.; Crippa, Federica; Rothen-Rutishauser, Barbara; Petri-Fink, Alke

    2017-08-01

    The ability to detect and accurately characterize particles is required by many fields of nanotechnology, including materials science, nanotoxicology, and nanomedicine. Among the most relevant physicochemical properties of nanoparticles, size and the related surface-to-volume ratio are fundamental ones. Taylor dispersion combines three independent phenomena to determine particle size: optical extinction, translational diffusion, and sheer-enhanced dispersion of nanoparticles subjected to a steady laminar flow. The interplay of these defines the apparent size. Considering that particles in fact are never truly uniform nor monodisperse, we rigorously address particle polydispersity and calculate the apparent particle size measured by Taylor dispersion analysis. We conducted case studies addressing aqueous suspensions of model particles and large-scale-produced "industrial" particles of both academic and commercial interest of various core materials and sizes, ranging from 15 to 100 nm. A comparison with particle sizes determined by transmission electron microscopy confirms that our approach is model-independent, non-parametric, and of general validity that provides an accurate account of size polydispersity—independently on the shape of the size distribution and without any assumption required a priori.

  18. Do corpo histérico ao "corpus" teórico

    Directory of Open Access Journals (Sweden)

    Francisco Ramos de Farias

    1992-09-01

    Full Text Available Este estudo aborda a maneira pela qual Freud, de forma original, efetuou uma leitura no corpo-sintoma da histérica e construiu uma clínica inédita destinada ao tratamento das neuroses. Esta clínica, fundada na transferência, é suportada pelo edifício teórico que tem o inconsciente e a sexualidade como paradigmas.

  19. 78 FR 20887 - Approval of Subzone Status; Pepsi Cola Puerto Rico Distributing, LLC, Toa Baja, Puerto Rico

    Science.gov (United States)

    2013-04-08

    ... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [S-132-2012] Approval of Subzone Status; Pepsi Cola Puerto Rico Distributing, LLC, Toa Baja, Puerto Rico On December 7, 2012, the Executive Secretary... activation limit of FTZ 7, on [[Page 20888

  20. Nozzle for electric dispersion reactor

    Science.gov (United States)

    Sisson, W.G.; Basaran, O.A.; Harris, M.T.

    1995-11-07

    A nozzle for an electric dispersion reactor includes two concentric electrodes, the inner one of the two delivering disperse phase fluid into a continuous phase fluid. A potential difference generated by a voltage source creates a dispersing electric field at the end of the inner electrode. 4 figs.

  1. Land Use, Conservation, Forestry, and Agriculture in Puerto Rico

    Directory of Open Access Journals (Sweden)

    William A. Gould

    2017-07-01

    Full Text Available Global food security concerns emphasize the need for sustainable agriculture and local food production. In Puerto Rico, over 80 percent of food is imported, and local production levels have reached historical lows. Efforts to increase local food production are driven by government agencies, non-government organizations, farmers, and consumers. Integration of geographic information helps plan and balance the reinvention and invigoration of the agriculture sector while maintaining ecological services. We used simple criteria that included currently protected lands and the importance of slope and forest cover in protection from erosion to identify land well-suited for conservation, agriculture and forestry in Puerto Rico. Within these categories we assessed U.S. Department of Agriculture (USDA farmland soils classification data, lands currently in agricultural production, current land cover, and current land use planning designations. We found that developed lands occupy 13 percent of Puerto Rico; lands well-suited for conservation that include protected areas, riparian buffers, lands surrounding reservoirs, wetlands, beaches, and salt flats, occupy 45 percent of Puerto Rico; potential working lands encompass 42 percent of Puerto Rico. These include lands well-suited for mechanized and non-mechanized agriculture, such as row and specialty crops, livestock, dairy, hay, pasture, and fruits, which occupy 23 percent of Puerto Rico; and areas suitable for forestry production, such as timber and non-timber products, agroforestry, and shade coffee, which occupy 19 percent of Puerto Rico.

  2. Tracer dispersion - experiment and CFD

    International Nuclear Information System (INIS)

    Zitny, R.

    2004-01-01

    Description of tracer distribution by means of dispersion models is a method successfully used in process engineering for fifty years. Application of dispersion models in reactor engineering for characterization of flows in column apparatus, heat exchangers, etc. is summarized and experimental tracer techniques as well as CFD methods for dispersion coefficients evaluation are discussed. Possible extensions of thermal axial dispersion model (ADM) and a core-wall ADM model suitable for description of tracer dispersion in laminar flows are suggested as well as CFD implementation as 1D finite elements. (author)

  3. High density dispersion fuel

    International Nuclear Information System (INIS)

    Hofman, G.L.

    1996-01-01

    A fuel development campaign that results in an aluminum plate-type fuel of unlimited LEU burnup capability with an uranium loading of 9 grams per cm 3 of meat should be considered an unqualified success. The current worldwide approved and accepted highest loading is 4.8 g cm -3 with U 3 Si 2 as fuel. High-density uranium compounds offer no real density advantage over U 3 Si 2 and have less desirable fabrication and performance characteristics as well. Of the higher-density compounds, U 3 Si has approximately a 30% higher uranium density but the density of the U 6 X compounds would yield the factor 1.5 needed to achieve 9 g cm -3 uranium loading. Unfortunately, irradiation tests proved these peritectic compounds have poor swelling behavior. It is for this reason that the authors are turning to uranium alloys. The reason pure uranium was not seriously considered as a dispersion fuel is mainly due to its high rate of growth and swelling at low temperatures. This problem was solved at least for relatively low burnup application in non-dispersion fuel elements with small additions of Si, Fe, and Al. This so called adjusted uranium has nearly the same density as pure α-uranium and it seems prudent to reconsider this alloy as a dispersant. Further modifications of uranium metal to achieve higher burnup swelling stability involve stabilization of the cubic γ phase at low temperatures where normally α phase exists. Several low neutron capture cross section elements such as Zr, Nb, Ti and Mo accomplish this in various degrees. The challenge is to produce a suitable form of fuel powder and develop a plate fabrication procedure, as well as obtain high burnup capability through irradiation testing

  4. A Cultural Resources Reconnaissance of Five Projects in Puerto Rico.

    Science.gov (United States)

    1980-01-01

    Memorias de Melgarejo). Melgarejo mentions that one of these three mills was located next to the mouth of the Loiza River, and that this was also the...Mexico. Cordova, Pedro Tomas de Memorias historicas de Puerto Rico. D-3 D’Alzina, Ismael 1957 Historia gr~fica de Puerto Rico, 1. Primera Epoca. Ed...Servidumbre de faja de terreno de 5.0 metros de ancho y 400.46 metros de largo a favor de la Autoridad de Acueductos y Alcantarillados de Puerto Rico

  5. Spurious dispersion effects at FLASH

    International Nuclear Information System (INIS)

    Prat, Eduard

    2009-07-01

    The performance of the Free-Electron Laser (FEL) process imposes stringent demands on the transverse trajectory and size of the electron beam. Since transverse dispersion changes off-energy particle trajectories and increases the effective beam size, dispersion must be controlled. This thesis treats the concept of dispersion in linacs, and analyses the impact of dispersion on the electron beam and on the FEL process. It presents generation mechanisms for spurious dispersion, quantifying its importance for FLASH (Free-electron Laser in Hamburg) and the XFEL (European X-ray Free-Electron Laser). A method for measuring and correcting dispersion and its implementation in FLASH is described. Experiments of dispersion e ects on the transverse beam quality and on the FEL performance are presented. (orig.)

  6. Spurious dispersion effects at FLASH

    Energy Technology Data Exchange (ETDEWEB)

    Prat, Eduard

    2009-07-15

    The performance of the Free-Electron Laser (FEL) process imposes stringent demands on the transverse trajectory and size of the electron beam. Since transverse dispersion changes off-energy particle trajectories and increases the effective beam size, dispersion must be controlled. This thesis treats the concept of dispersion in linacs, and analyses the impact of dispersion on the electron beam and on the FEL process. It presents generation mechanisms for spurious dispersion, quantifying its importance for FLASH (Free-electron Laser in Hamburg) and the XFEL (European X-ray Free-Electron Laser). A method for measuring and correcting dispersion and its implementation in FLASH is described. Experiments of dispersion e ects on the transverse beam quality and on the FEL performance are presented. (orig.)

  7. Dispersion stability of thermal nanofluids

    Directory of Open Access Journals (Sweden)

    Fan Yu

    2017-10-01

    Full Text Available Thermal nanofluids, the engineered fluids with dispersed functional nanoparticles, have exhibited extraordinary thermophysical properties and added functionalities, and thus have enabled a broad range of important applications. The poor dispersion stability of thermal nanofluids, however, has been considered as a long-existing issue that limits their further development and practical application. This review overviews the recent efforts and progresses in improving the dispersion stability of thermal nanofluids such as mechanistic understanding of dispersion behavior of nanofluids, examples of both water-based and oil-based nanofluids, strategies to stabilize nanofluids, and characterization techniques for dispersion behavior of nanofluids. Finally, on-going research needs, and possible solutions to research challenges and future research directions in exploring stably dispersed thermal nanofluids are discussed. Keywords: Thermal nanofluids, Dispersion, Aggregation, Electrostatic stabilization, Steric stabilization

  8. Iberian urbanism in Contestania | En torno al urbanismo ibérico de la Contestania

    Directory of Open Access Journals (Sweden)

    Lorenzo Abad Casal

    2007-12-01

    Full Text Available The organization of the poblamiento and the origin of the models of Iberian dispersion and distribution, from the historical works developed within the framework of the old Contestania and of their surroundings are studied. Changes in the patterns of establishment throughout second half of the first millenium b.C. and the existence of a regular urban pattern in the origins of some establishments, mainly coastal, are documented . We paid attention to phenomena of modulation, internal organization and its more outstanding buildings. | Se estudia la organización del poblamiento y el origen de los modelos de dispersión y distribución ibéricos, a partir de los trabajos históricos desarrollados en el marco de la antigua Contestania y de su entorno. Se documenta un cambio en los patrones de asentamiento a lo largo de la segunda mitad del primer milenio antes de nuestra era. Se destaca la existencia de un patrón urbano regular en los orígenes de algunos asentamientos, sobre todo costeros. Se estudian los fenómenos de modulación detectados, su organización interna y la de sus edificios más destacados.

  9. Phonon dispersion in vanadium

    International Nuclear Information System (INIS)

    Ivanov, A.S.; Rumiantsev, A.Yu.

    1999-01-01

    Complete text of publication follows. Phonon dispersion curves in Vanadium metal are investigated by neutron inelastic scattering using three-axis spectrometers. Due to extremely low coherent scattering amplitude of neutrons in natural isotope mixture of vanadium the phonon frequencies could be determined in the energy range below about 15 meV. Several phonon groups were measured with the polarised neutron scattering set-up. It is demonstrated that the intensity of coherent inelastic scattering observed in the non-spin-flip channel vanishes in the spin-flip channel. The phonon density of states is measured on a single crystal keeping the momentum transfer equal to a vector of reciprocal lattice where the coherent inelastic scattering is suppressed. Phonon dispersion curves in vanadium, as measured by neutron and earlier by X-ray scattering, are described in frames of a charge-fluctuation model involving monopolar and dipolar degrees of freedom. The model parameters are compared for different transition metals with body-centred cubic-structure. (author)

  10. Dispersion and current measurements

    International Nuclear Information System (INIS)

    Boelskifte, S.

    1986-04-01

    A model for the simulation of particle movements in water should incorporate the mutual distance dependent correlation. As long as reliable data are given accessible a model can be created of the dispersion in a given area from a statistical description of turbulence. Current measurements have been performed in an area north of the Swedish nuclear power plant Barsebaeck, and statistical time series analysis have made it possible to estimate multivariate autoregressive moving-average (ARMA) models for these data using the Box-Jenkins method. The correlation structure for the area has been investigated in detail. Transport and dispersion models for the marine environment are used in estimating doses to the population from the aquatic food chain. Some of these models are described with special emphasis on the time and length scales they cover. Furthermore, to illustrate the background of the simulation model, short introductuions are given to health physics, time series analysis, and turbulence theory. Analysis of the simulation model shows the relative importance of the different parameters. The model can be expanded to conditional simulation, where the current measurements are used directly to simulate the movement of one of the particles. Results from the model are also compared to results from a sampling of bioindicators (Fucus vesiculosus) along the Danish coast. The reliability of bioindicators in this kind of experiment is discussed. (author)

  11. Quantum optical rotatory dispersion

    Science.gov (United States)

    Tischler, Nora; Krenn, Mario; Fickler, Robert; Vidal, Xavier; Zeilinger, Anton; Molina-Terriza, Gabriel

    2016-01-01

    The phenomenon of molecular optical activity manifests itself as the rotation of the plane of linear polarization when light passes through chiral media. Measurements of optical activity and its wavelength dependence, that is, optical rotatory dispersion, can reveal information about intricate properties of molecules, such as the three-dimensional arrangement of atoms comprising a molecule. Given a limited probe power, quantum metrology offers the possibility of outperforming classical measurements. This has particular appeal when samples may be damaged by high power, which is a potential concern for chiroptical studies. We present the first experiment in which multiwavelength polarization-entangled photon pairs are used to measure the optical activity and optical rotatory dispersion exhibited by a solution of chiral molecules. Our work paves the way for quantum-enhanced measurements of chirality, with potential applications in chemistry, biology, materials science, and the pharmaceutical industry. The scheme that we use for probing wavelength dependence not only allows one to surpass the information extracted per photon in a classical measurement but also can be used for more general differential measurements. PMID:27713928

  12. Geology of Isla de Mona, Puerto Rico

    Science.gov (United States)

    Frank, E.F.; Wicks, Carol M.; Mylroie, J.; Troester, J.; Alexander, E.C.; Carew, J.L.

    1998-01-01

    Isla de Mona is a carbonate island located in the Mona Passage 68 km west of Puerto Rico. The tectonically uplifted island is 12 km by 5 km, with an area of 55 km2, and forms a raised flat-topped platform or meseta. The meseta tilts gently to the south and is bounded by near vertical cliffs on all sides. These cliffs rise from 80 m above sea level on the north to 20 m above the sea on the southern coast. Along the southwestern and western side of the island a three- to six-meter-high Pleistocene fossil reef abuts the base of the cliff to form a narrow coastal plain. The meseta itself consists of two Mio-Pliocene carbonate units, the lower Isla de Mona Dolomite and the upper Lirio Limestone. Numerous karst features, including a series of flank margin caves primarily developed at the Lirio Limestone/Isla de Mona Dolomite contact, literally ring the periphery of the island.

  13. Plasma rico en plaquetas Platelet -rich plasma

    Directory of Open Access Journals (Sweden)

    J. González Lagunas

    2006-04-01

    Full Text Available El Plasma Rico en Plaquetas es una suspensión concentrada de la sangre centrifugada que contiene elevadas concentraciones de trombocitos. Durante los últimos años, este producto ha aparecido de forma repetida en publicaciones científicas y en medios de comunicación generales como un producto que por sus características induce la curación y regeneración de los tejidos. La premisa de su uso es que las elevadas concentraciones de plaquetas en el PRP, liberan cantidades significativas de factores de crecimiento. En este artículo se van a recoger las evidencias científicas que se han presentado en la literatura médica con respecto al PRP y a la curación ósea, así como las diferentes aplicaciones clínicas que se han sugerido.Platelet-rich plasma is a by-product of centrifuged whole blood that contains high levels of thrombocytes. In the last decade, scientific and media interest has been generated by this product that apparently has the capacity of inducing and promoting tissue healing and regeneration. The premise of its use is that the large number of platelets in PRP release significant amounts of growth factors. In this paper, a critical review of the medical literature regarding PRP and bone healing will be presented. Also, the suggested clinical applications of the product will be addressed.

  14. Economic Cost of Dengue in Puerto Rico

    Science.gov (United States)

    Halasa, Yara A.; Shepard, Donald S.; Zeng, Wu

    2012-01-01

    Dengue, endemic in Puerto Rico, reached a record high in 2010. To inform policy makers, we derived annual economic cost. We assessed direct and indirect costs of hospitalized and ambulatory dengue illness in 2010 dollars through surveillance data and interviews with 100 laboratory-confirmed dengue patients treated in 2008–2010. We corrected for underreporting by using setting-specific expansion factors. Work absenteeism because of a dengue episode exceeded the absenteeism for an episode of influenza or acute otitis media. From 2002 to 2010, the aggregate annual cost of dengue illness averaged $38.7 million, of which 70% was for adults (age 15+ years). Hospitalized patients accounted for 63% of the cost of dengue illness, and fatal cases represented an additional 17%. Households funded 48% of dengue illness cost, the government funded 24%, insurance funded 22%, and employers funded 7%. Including dengue surveillance and vector control activities, the overall annual cost of dengue was $46.45 million ($12.47 per capita). PMID:22556069

  15. Vicariance, long-distance dispersal, and regional extinction-recolonization dynamics explain the disjunct circumpolar distribution of the arctic-alpine plant Silene acaulis.

    Science.gov (United States)

    Gussarova, Galina; Allen, Geraldine A; Mikhaylova, Yulia; McCormick, Laurie J; Mirré, Virginia; Marr, Kendrick L; Hebda, Richard J; Brochmann, Christian

    2015-10-01

    Many arctic-alpine species have vast geographic ranges, but these may encompass substantial gaps whose origins are poorly understood. Here we address the phylogeographic history of Silene acaulis, a perennial cushion plant with a circumpolar distribution except for a large gap in Siberia. We assessed genetic variation in a range-wide sample of 103 populations using plastid DNA (pDNA) sequences and AFLPs (amplified fragment length polymorphisms). We constructed a haplotype network and performed Bayesian phylogenetic analyses based on plastid sequences. We visualized AFLP patterns using principal coordinate analysis, identified genetic groups using the program structure, and estimated genetic diversity and rarity indices by geographic region. The history of the main pDNA lineages was estimated to span several glaciations. AFLP data revealed a distinct division between Beringia/North America and Europe/East Greenland. These two regions shared only one of 17 pDNA haplotypes. Populations on opposite sides of the Siberian range gap (Ural Mountains and Chukotka) were genetically distinct and appear to have resulted from postglacial leading-edge colonizations. We inferred two refugia in North America (Beringia and the southern Rocky Mountains) and two in Europe (central-southern Europe and northern Europe/East Greenland). Patterns in the East Atlantic region suggested transoceanic long-distance dispersal events. Silene acaulis has a highly dynamic history characterized by vicariance, regional extinction, and recolonization, with persistence in at least four refugia. Long-distance dispersal explains patterns across the Atlantic Ocean, but we found no evidence of dispersal across the Siberian range gap. © 2015 Botanical Society of America.

  16. Metapopulation extinction risk: dispersal's duplicity.

    Science.gov (United States)

    Higgins, Kevin

    2009-09-01

    Metapopulation extinction risk is the probability that all local populations are simultaneously extinct during a fixed time frame. Dispersal may reduce a metapopulation's extinction risk by raising its average per-capita growth rate. By contrast, dispersal may raise a metapopulation's extinction risk by reducing its average population density. Which effect prevails is controlled by habitat fragmentation. Dispersal in mildly fragmented habitat reduces a metapopulation's extinction risk by raising its average per-capita growth rate without causing any appreciable drop in its average population density. By contrast, dispersal in severely fragmented habitat raises a metapopulation's extinction risk because the rise in its average per-capita growth rate is more than offset by the decline in its average population density. The metapopulation model used here shows several other interesting phenomena. Dispersal in sufficiently fragmented habitat reduces a metapopulation's extinction risk to that of a constant environment. Dispersal between habitat fragments reduces a metapopulation's extinction risk insofar as local environments are asynchronous. Grouped dispersal raises the effective habitat fragmentation level. Dispersal search barriers raise metapopulation extinction risk. Nonuniform dispersal may reduce the effective fraction of suitable habitat fragments below the extinction threshold. Nonuniform dispersal may make demographic stochasticity a more potent metapopulation extinction force than environmental stochasticity.

  17. Radionuclide content of soils from Barrio Islote, Arecibo, Puerto Rico

    International Nuclear Information System (INIS)

    Block, A.McB.; Clements, R.G.

    1976-06-01

    The purpose of this report is to present and interpret gamma ray energy spectra from natural radioactivity and fallout radionuclides measured on soil samples collected in the projected thermonuclear power plant exclusion zone in Barrio Islote, Puerto Rico

  18. Américo Negrette and Huntington's disease

    Directory of Open Access Journals (Sweden)

    Mariana Moscovich

    2011-08-01

    Full Text Available The authors present a historical review of the seminal clinical contribution of Professor Américo Negrette, a Venezuelan neurologist, to the evolution of scientific knowledge about Huntington's disease.

  19. Northeast Puerto Rico and Culebra Island Ground Validation Points 2015

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This shapefile denotes the location of underwater photos and videos taken in shallow water (0-35m) benthic habitats surrounding Northeast Puerto Rico and Culebra...

  20. Northeast Puerto Rico and Culebra Island Accuracy Assessment Points - 2015

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This shapefile denotes the location of underwater photos and videos taken in shallow water (0-35m) benthic habitats surrounding Northeast Puerto Rico and Culebra...

  1. Puerto Rico ESI/RSI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) and Reach Sensitivity Index (RSI) data for Puerto Rico. ESI data characterize estuarine...

  2. Puerto Rico ESI/RSI: T_MAMMAL (Terrestrial Mammals)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) and Reach Sensitivity Index (RSI) data for Puerto Rico. ESI data characterize estuarine...

  3. Puerto Rico ESI/RSI: SOCECON (Socioeconomic Lines and Points)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) and Reach Sensitivity Index (RSI) data for Puerto Rico. ESI data characterize estuarine...

  4. Puerto Rico ESI and RSI: SHELFBND (Shelf Boundary)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) and Reach Sensitivity Index (RSI) data for Puerto Rico. ESI data characterize estuarine...

  5. Puerto Rico ESI/RSI: BENTHIC (Benthic Marine Habitats)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) and Reach Sensitivity Index (RSI) data for Puerto Rico. ESI data characterize estuarine...

  6. Puerto Rico ESI/RSI: MGT (Management Areas)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) and Reach Sensitivity Index (RSI) data for Puerto Rico. ESI data characterize estuarine...

  7. Puerto Rico ESI/RSI: INVERT (Invertebrate Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) and Reach Sensitivity Index (RSI) data for Puerto Rico. ESI data characterize estuarine...

  8. National Status and Trends: Guanica, Puerto Rico Contaminants Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This project assesses chemical contaminant status in sediment and coral tissues (Porites astroides) collected in and around Guanica Bay, Puerto Rico in 2009....

  9. 75 FR 68393 - Puerto Rico Disaster # PR-00011

    Science.gov (United States)

    2010-11-05

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12366 and 12367] Puerto Rico Disaster PR-00011 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster [[Page 68394

  10. Particulate Air Contamination in Puerto Rico: A Student Involvement Project.

    Science.gov (United States)

    Eckert, Richard R.

    1979-01-01

    Describes a research project undertaken by physics undergraduate students to monitor particulate air contamination in Ponce, Puerto Rico, and to determine the meteorological factors which contribute to it. (GA)

  11. Summit to Sea Characterization of Coastal Watersheds - Puerto Rico 2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This Characterization of Coastal Watershed for Puerto Rico, Culebra Island and Vieques Island, is a GIS products suite consisting of layers derived from diverse...

  12. Fajardo, Puerto Rico Tsunami Forecast Grids for MOST Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Fajardo, Puerto Rico Forecast Model Grids provides bathymetric data strictly for tsunami inundation modeling with the Method of Splitting Tsunami (MOST) model....

  13. Ponce, Puerto Rico Tsunami Forecast Grids for MOST Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Ponce, Puerto Rico Forecast Model Grids provides bathymetric data strictly for tsunami inundation modeling with the Method of Splitting Tsunami (MOST) model....

  14. Shallow-Water Benthic Habitats of Southwest Puerto Rico

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Shallow-water (<30m) benthic habitat maps of the nearshore marine environment of two areas in Southwest Puerto Rico (PR), including the Guanica Bay/La Parguera...

  15. Puerto Rico ESI/RSI: INVERT (Invertebrate Lines)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) and Reach Sensitivity Index (RSI) data for Puerto Rico. ESI data characterize estuarine...

  16. Arecibo, Puerto Rico Tsunami Forecast Grids for MOST Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Arecibo, Puerto Rico Forecast Model Grids provides bathymetric data strictly for tsunami inundation modeling with the Method of Splitting Tsunami (MOST) model....

  17. San Juan, Puerto Rico Tsunami Forecast Grids for MOST Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The San Juan, Puerto Rico Forecast Model Grids provides bathymetric data strictly for tsunami inundation modeling with the Method of Splitting Tsunami (MOST) model....

  18. Puerto Rico ESI/RSI: FISHL (Fish Lines)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) and Reach Sensitivity Index (RSI) data for Puerto Rico. ESI data characterize estuarine...

  19. Puerto Rico ESI/RSI: REPTILES (Reptiles and Amphibians)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) and Reach Sensitivity Index (RSI) data for Puerto Rico. ESI data characterize estuarine...

  20. Rainfall-induced landslide susceptibility zonation of Puerto Rico

    Science.gov (United States)

    Chiara Lepore; Sameer A. Kamal; Peter Shanahan; Rafael L. Bras

    2011-01-01

    Landslides are a major geologic hazard with estimated tens of deaths and $1–2 billion in economic losses per year in the US alone. The island of Puerto Rico experiences one or two large events per year, often triggered in steeply sloped areas by prolonged and heavy rainfall. Identifying areas susceptible to landslides thus has great potential value for Puerto Rico and...

  1. 20 CFR 404.1089 - Figuring net earnings for residents and nonresidents of Puerto Rico.

    Science.gov (United States)

    2010-04-01

    ... nonresidents of Puerto Rico. 404.1089 Section 404.1089 Employees' Benefits SOCIAL SECURITY ADMINISTRATION... Puerto Rico. (a) Residents. If you are a resident of Puerto Rico, whether or not you are an alien, a citizen of the United States, or a citizen of Puerto Rico, you must figure your net earnings from self...

  2. Relativistic plasma dispersion functions

    International Nuclear Information System (INIS)

    Robinson, P.A.

    1986-01-01

    The known properties of plasma dispersion functions (PDF's) for waves in weakly relativistic, magnetized, thermal plasmas are reviewed and a large number of new results are presented. The PDF's required for the description of waves with small wave number perpendicular to the magnetic field (Dnestrovskii and Shkarofsky functions) are considered in detail; these functions also arise in certain quantum electrodynamical calculations involving strongly magnetized plasmas. Series, asymptotic series, recursion relations, integral forms, derivatives, differential equations, and approximations for these functions are discussed as are their analytic properties and connections with standard transcendental functions. In addition a more general class of PDF's relevant to waves of arbitrary perpendicular wave number is introduced and a range of properties of these functions are derived

  3. Skin cancer in Puerto Rico: a multiannual incidence comparative study.

    Science.gov (United States)

    De La Torre-Lugo, Eneida M; Figueroa, Luz D; Sánchez, Jorge L; Morales-Burgos, Adisbeth; Conde, Daniel

    2010-09-01

    The incidence of skin cancer continues to increase worldwide. The purpose of this study was to determine the incidence of skin cancer in Puerto Rico in a selected year (2005) and to compare these findings with those previously reported for Puerto Rico in 1974 and 1981 and with other countries. The data was collected from the pathology reports corresponding to the period of January to December 2005 of 21 participating Pathology Laboratories throughout Puerto Rico. The rate and distribution of the main types of skin cancer was calculated based on sex, age, anatomic location and laterality. The incidence of skin cancer in Puerto Rico for 2005 was 6,568 cases, which represent a rate of 167.9 per 100,000 inhabitants. The most common type of skin cancer was basal-cell carcinoma. Skin cancer was more common in males except for melanoma, which was more common in females. The incidence increases with age on all types of skin cancer. The head and neck area was the most frequent location, except for melanoma in women, which was more common on the legs. The incidence rate was 41.5/100,000 in 1974, 52.5/100,000 in 1981 and 167.9/100,000 in 2005, a 305% increase. We found an increasing incidence of skin cancer in Puerto Rico when compared with previous reported data. This analysis provides a comprehensive evaluation of the epidemiology of skin cancer in Puerto Rico.

  4. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands;Photomosaic of Puerto Rico (Salinas), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  5. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands;Photomosaic of Puerto Rico (Maunabo), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  6. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands; Photomosaic of Puerto Rico (Isla de Mona), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  7. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands; Photomosaic of Puerto Rico (Ceiba), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  8. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands;Photomosaic of Puerto Rico (Luquillo), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  9. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands; Photomosaic of Puerto Rico (Maunabo), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  10. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands; Photomosaic of Puerto Rico (Isla de Desecheo), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  11. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands; Photomosaic of Puerto Rico (Barceloneta), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  12. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands; Photomosaic of Puerto Rico (San Juan), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  13. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands; Photomosaic of Puerto Rico (Salinas), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  14. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands;Photomosaic of Puerto Rico (Barcelon), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  15. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands;Photomosaic of Puerto Rico (Arroyo), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  16. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands;Photomosaic of Puerto Rico (East Culebra), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  17. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands;Photomosaic of Puerto Rico (La Pargue), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  18. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands;Photomosaic of Puerto Rico (Candelero), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  19. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands; Photomosaic of Puerto Rico (Rincon), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  20. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands;Photomosaic of Puerto Rico (Guayanil), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  1. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands; Photomosaic of Puerto Rico (La Parguera), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  2. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands; Photomosaic of Puerto Rico (Mayaguez), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  3. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands;Photomosaic of Puerto Rico (Cabo Rojo), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  4. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands; Photomosaic of Puerto Rico (Cabo Rojo), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  5. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands; Photomosaic of Puerto Rico (East Culebra), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  6. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands; Photomosaic of Puerto Rico (Isla de Vieques), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  7. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands; Photomosaic of Puerto Rico (Isla de Culebra), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  8. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands; Photomosaic of Puerto Rico (Ponce), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  9. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands; Photomosaic of Puerto Rico (Isabela), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  10. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands; Photomosaic of Puerto Rico (Candelero), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  11. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands; Photomosaic of Puerto Rico (Arroyo), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  12. Statistical Thermodynamics of Disperse Systems

    DEFF Research Database (Denmark)

    Shapiro, Alexander

    1996-01-01

    Principles of statistical physics are applied for the description of thermodynamic equilibrium in disperse systems. The cells of disperse systems are shown to possess a number of non-standard thermodynamic parameters. A random distribution of these parameters in the system is determined....... On the basis of this distribution, it is established that the disperse system has an additional degree of freedom called the macro-entropy. A large set of bounded ideal disperse systems allows exact evaluation of thermodynamic characteristics. The theory developed is applied to the description of equilibrium...

  13. Geometry of physical dispersion relations

    International Nuclear Information System (INIS)

    Raetzel, Dennis; Rivera, Sergio; Schuller, Frederic P.

    2011-01-01

    To serve as a dispersion relation, a cotangent bundle function must satisfy three simple algebraic properties. These conditions are derived from the inescapable physical requirements that local matter field dynamics must be predictive and allow for an observer-independent notion of positive energy. Possible modifications of the standard relativistic dispersion relation are thereby severely restricted. For instance, the dispersion relations associated with popular deformations of Maxwell theory by Gambini-Pullin or Myers-Pospelov are not admissible. Dispersion relations passing the simple algebraic checks derived here correspond to physically admissible Finslerian refinements of Lorentzian geometry.

  14. Dispersion bias, dispersion effect, and the aerosol-cloud conundrum

    International Nuclear Information System (INIS)

    Liu Yangang; Daum, Peter H; Guo Huan; Peng Yiran

    2008-01-01

    This work examines the influences of relative dispersion (the ratio of the standard deviation to the mean radius of the cloud droplet size distribution) on cloud albedo and cloud radiative forcing, derives an analytical formulation that accounts explicitly for the contribution from droplet concentration and relative dispersion, and presents a new approach to parameterize relative dispersion in climate models. It is shown that inadequate representation of relative dispersion in climate models leads to an overestimation of cloud albedo, resulting in a negative bias of global mean shortwave cloud radiative forcing that can be comparable to the warming caused by doubling CO 2 in magnitude, and that this dispersion bias is likely near its maximum for ambient clouds. Relative dispersion is empirically expressed as a function of the quotient between cloud liquid water content and droplet concentration (i.e., water per droplet), yielding an analytical formulation for the first aerosol indirect effect. Further analysis of the new expression reveals that the dispersion effect not only offsets the cooling from the Twomey effect, but is also proportional to the Twomey effect in magnitude. These results suggest that unrealistic representation of relative dispersion in cloud parameterization in general, and evaluation of aerosol indirect effects in particular, is at least in part responsible for several outstanding puzzles of the aerosol-cloud conundrum: for example, overestimation of cloud radiative cooling by climate models compared to satellite observations; large uncertainty and discrepancy in estimates of the aerosol indirect effect; and the lack of interhemispheric difference in cloud albedo.

  15. Historical biogeographic analysis of the family Fanniidae (Díptera: Calyptratae, with special reference to the austral species of the genus Fannia (Diptera: Fanniidae using dispersal-vicariance analysis Análisis biogeográfico histórico de la familia Fanniidae (Diptera: Calyptratae, con referencia especial a las especies australes del genero Fannia (Diptera: Fanniidae usando análisis de dipersion-vicarianza

    Directory of Open Access Journals (Sweden)

    M. CECILIA DOMÍNGUEZ

    2011-03-01

    Full Text Available The purpose of this study was to achieve a hypothesis explaining the biogeographical history of the family Fanniidae, especially that of the species from Patagonia, the Neotropics, Australia, and New Zealand. We used "dispersal-vicariance analysis" (DIVA, an event-based parsimony method, to analyze the most parsimonious phylogenetic hypothesis for the family, obtained by Domínguez & Roig-Juñent (2008. The analysis resulted in 32800 alternative equally optimal reconstructions that indicate that the ancestor of the Fanniidae was widely distributed across different regions of the world, which along with the subsequent separation of two clades that correspond to the Laurasic and Gondwanan Landmasses allow the proposal of an older age than in previous hypothesis (Late Jurassic or early Cretaceous times instead of upper Cretaceous and a Pangeic origin for the Fanniidae. The northern hemisphere species of Fanniidae included in this study highlight the difficulty that arises when analysing with DIVA a tree with a large amount of paralogy or redundant distributions, as illustrated here with several examples. The southern hemisphere species of Fanniidae indicate a clear pattern of vicariance and dispersal consistent with the rupture of Gondwana.El propósito de este estudio fue el de obtener una hipótesis que explique la historia biogeográfica de la familia Fanniidae, especialmente la de las especies de las regiones Patagónica, Neotropical, Australiana y Neozelandesa. Se utilizó el método de "dispersión y vicarianza" (DIVA, el cual es un método de parsimonia basado en eventos para analizar el árbol filogenético más parsimonioso obtenido por Domínguez & Roig-Juñent (2008. El análisis resultó en 32800 reconstrucciones alternativas igualmente óptimas que indican que el ancestro de Fanniidae estaba ampliamente distribuido en distintas regiones del mundo, lo cual junto con la subsiguiente separación de dos clados que corresponderían a los

  16. Invasive cancer incidence - Puerto Rico, 2007-2011.

    Science.gov (United States)

    O'Neil, Mary Elizabeth; Henley, S Jane; Singh, Simple D; Wilson, Reda J; Ortiz-Ortiz, Karen J; Ríos, Naydi Pérez; Torres Cintrón, Carlos R; Luna, Guillermo Tortolero; Zavala Zegarra, Diego E; Ryerson, A Blythe

    2015-04-17

    Cancer is a leading cause of morbidity and death in Puerto Rico. To set a baseline for identifying new trends and patterns of cancer incidence, Puerto Rico Central Cancer Registry staff and CDC analyzed data from Puerto Rico included in U.S. Cancer Statistics (USCS) for 2007-2011, the most recent data available. This is the first report of invasive cancer incidence rates for 2007-2011 among Puerto Rican residents by sex, age, cancer site, and municipality. Cancer incidence rates in Puerto Rico were compared with those in the U.S. population for 2011. A total of 68,312 invasive cancers were diagnosed and reported in Puerto Rico during 2007-2011. The average annual incidence rate was 330 cases per 100,000 persons. The cancer sites with the highest cancer incidence rates included prostate (152), female breast (84), and colon and rectum (43). Cancer incidence rates varied by municipality, particularly for prostate, lung and bronchus, and colon and rectum cancers. In 2011, cancer incidence rates in Puerto Rico were lower for all cancer sites and lung and bronchus, but higher for prostate and thyroid cancers, compared with rates within the U.S. Identifying these variations can aid evaluation of factors associated with high incidence, such as cancer screening practices, and development of targeted cancer prevention and control efforts. Public health professionals can monitor cancer incidence trends and use these findings to evaluate the impact of prevention efforts, such as legislation prohibiting tobacco use in the workplace and public places and the Puerto Rico Cessation Quitline in decreasing lung and other tobacco-related cancers.

  17. Puerto Rico and Florida manatees represent genetically distinct groups

    Science.gov (United States)

    Hunter, Margaret E.; Mignucci-Giannoni, Antonio A.; Tucker, Kimberly Pause; King, Timothy L.; Bonde, Robert K.; Gray, Brian A.; McGuire, Peter M.

    2012-01-01

    The West Indian manatee (Trichechus manatus) populations in Florida (T. m. latirostris) and Puerto Rico (T. m. manatus) are considered distinct subspecies and are listed together as endangered under the United States Endangered Species Act. Sustained management and conservation efforts for the Florida subspecies have led to the suggested reclassification of the species to a threatened or delisted status. However, the two populations are geographically distant, morphologically distinct, and habitat degradation and boat strikes continue to threaten the Puerto Rico population. Here, 15 microsatellite markers and mitochondrial control region sequences were used to determine the relatedness of the two populations and investigate the genetic diversity and phylogeographic organization of the Puerto Rico population. Highly divergent allele frequencies were identified between Florida and Puerto Rico using microsatellite (F ST = 0.16; R ST = 0.12 (P ST = 0.66; Φ ST = 0.50 (P E = 0.45; NA = 3.9), were similar, but lower than those previously identified in Florida (HE = 0.48, NA = 4.8). Within Puerto Rico, the mitochondrial genetic diversity values (π = 0.001; h = 0.49) were slightly lower than those previously reported (π = 0.002; h = 0.54) and strong phylogeographic structure was identified (F ST global = 0.82; Φ ST global = 0.78 (P population size (N = 250), and distinct threats and habitat emphasize the need for separate protections in Puerto Rico. Conservation efforts including threat mitigation, migration corridors, and protection of subpopulations could lead to improved genetic variation in the endangered Puerto Rico manatee population.

  18. Auroral electron time dispersion

    International Nuclear Information System (INIS)

    Kletzing, C.A.

    1989-01-01

    A sounding rocket flight was launched from Greenland in 1985 to study high latitude, early morning auroral physics. The payload was instrumented with electron and ion detectors, AC and DC electric field experiments, a plasma density experiment, and a magnetometer to measure the ambient field. The rocket was launched during disturbed conditions, when the polar cap was in a contracted state with visible aurora overhead. The electron data contained numerous signatures indicative of time-of-flight energy dispersion characterized by a coherent structure in which lower energy electrons arrived at the rocket after higher energy electrons. A model was constructed to explain this phenomena by the sudden application of a region of parallel electric field along a length of magnetic field line above the rocket. The model incorporates detector response and uses an altitudinal density profile based on auroral zone measurements. Three types of potential structures were tried: linear, quadratic and cubic. Of the three it was found that the cubic (electric field growing in a quadratic manner moving up the field line) produced the best fit to the data. The potential region was found to be approximately 1-2 R e in extent with the lower edge 3000-4000 km away from the rocket. The background electron temperature in the model which produced the best fit to the data was of the order of 15 eV

  19. Dispersal and migration

    Directory of Open Access Journals (Sweden)

    Schwarz, C.

    2004-06-01

    Full Text Available Ringing of birds unveiled many aspects of avian migration and dispersal movements. However, there is even much more to be explored by the use of ringing and other marks. Dispersal is crucial in understanding the initial phase of migration in migrating birds as it is to understand patterns and processes of distribution and gene flow. So far, the analysis of migration was largely based on analysing spatial and temporal patters of recoveries of ringed birds. However, there are considerable biases and pitfalls in using recoveries due to spatial and temporal variation in reporting probabilities. Novel methods are required for future studies separating the confounding effects of spatial and temporal heterogeneity of recovery data and heterogeneity of the landscape as well. These novel approaches should aim a more intensive and novel use of the existing recovery data by taking advantage of, for instance, dynamic and multistate modeling, should elaborate schemes for future studies, and should also include other marks that allow a more rapid data collection, like telemetry, geolocation and global positioning systems, and chemical and molecular markers. The latter appear to be very useful in the delineating origin of birds and connectivity between breeding and non–breeding grounds. Many studies of migration are purely descriptive. However, King and Brooks (King & Brooks, 2004 examine if movement patterns of dolphins change after the introduction of a gillnet ban. Bayesian methods are an interesting approach to this problem as they provide a meaningful measure of the probability that such a change occurred rather than simple yes/no response that is often the result of classical statistical methods. However, the key difficulty of a general implementation of Bayesian methods is the complexity of the modelling —there is no general userfriendly package that is easily accessible to most scientists. Drake and Alisauskas (Drake & Alisauskas, 2004 examine the

  20. Progress in urban dispersion studies

    DEFF Research Database (Denmark)

    Batchvarova, E.; Gryning, Sven-Erik

    2006-01-01

    The present Study addresses recent achievements in better representation Of the urban area structure in meteorology and dispersion parameterisations. The setup and Main Outcome of several recent dispersion experiments in Urban areas and their use in model validation are discussed. The maximum con...

  1. Nest-mediated seed dispersal

    Science.gov (United States)

    Robert J. Warren; Jason P. Love; Mark A. Bradford

    2017-01-01

    Many plant seeds travel on the wind and through animal ingestion or adhesion; however, an overlooked dispersal mode may lurk within those dispersal modes. Viable seeds may remain attached or embedded within materials birds gather for nest building. Our objective was to determine if birds inadvertently transport seeds when they forage for plant materials to...

  2. Definition of global dispersion coefficients

    International Nuclear Information System (INIS)

    Naff, R.L.

    1983-10-01

    For estimation of a global longitudinal dispersivity at the Gorleben site, data available primarily consist of suites of geophysical logs from wells penetrating the Quaternary aquifer. A length scale for the principle aquifer at Gorleben is to be found. Samples are to be taken separately to estimate the variance in hydraulic conductivity (Taylor Analysis, Fickian dispersion process). (DG)

  3. Source, Use, and Disposition of Freshwater in Puerto Rico, 2005

    Science.gov (United States)

    Molina-Rivera, Wanda L.

    2010-01-01

    Water diverted from streams and pumped from wells constitutes the main sources of water for the 78 municipios of the Commonwealth of Puerto Rico. A better understanding is needed about water-use patterns, particularly about the amount of water used, where and how this water is used and disposed, and how human activities impact water resources. Irrigation practices, indoor and outdoor household uses, industrial uses, and commercial and mining withdrawals affect reservoirs, streams, and aquifers. Accurate and accessible water information for Puerto Rico is critical to ensure that water managers have the ability to protect and conserve this natural resource. The population of Puerto Rico increased 15 percent, from 3.4 million in 1985 to 3.9 million people 2005 and resulted in an increased demand for freshwater, mostly for the public-supply water use category. Almost 99 percent of the residents in Puerto Rico were served by public-supply water systems in 2005. One of the major challenges that water managers confront is the need to provide sufficient freshwater availability in the densely populated areas. Public-supply water is provided by the Puerto Rico Aqueducts and Sewers Authority (PRASA) and by non-PRASA systems. Non-PRASA systems refer to community-operated water systems (water systems that serve a rural or suburban housing area).

  4. Wave-equation dispersion inversion

    KAUST Repository

    Li, Jing

    2016-12-08

    We present the theory for wave-equation inversion of dispersion curves, where the misfit function is the sum of the squared differences between the wavenumbers along the predicted and observed dispersion curves. The dispersion curves are obtained from Rayleigh waves recorded by vertical-component geophones. Similar to wave-equation traveltime tomography, the complicated surface wave arrivals in traces are skeletonized as simpler data, namely the picked dispersion curves in the phase-velocity and frequency domains. Solutions to the elastic wave equation and an iterative optimization method are then used to invert these curves for 2-D or 3-D S-wave velocity models. This procedure, denoted as wave-equation dispersion inversion (WD), does not require the assumption of a layered model and is significantly less prone to the cycle-skipping problems of full waveform inversion. The synthetic and field data examples demonstrate that WD can approximately reconstruct the S-wave velocity distributions in laterally heterogeneous media if the dispersion curves can be identified and picked. The WD method is easily extended to anisotropic data and the inversion of dispersion curves associated with Love waves.

  5. Cardiovascular services and human resources in Puerto Rico - 2008.

    Science.gov (United States)

    García-Palmieri, Mario R

    2009-01-01

    Available information (2004-2008) concerning population statistics, the occurrence of cardiovascular disease, cardiovascular services and human resources in Puerto Rico is presented. Relevant information concerning life expectancy at birth, death by specific causes in a recent four years period, the commonest causes of death, and the related cardiovascular risk factors prevalence data available is included. The surgical and medical interventional services rendered to cardiovascular patients in different institutions and their locations in Puerto Rico in the year 2008 is presented. Some remarks concerning the productivity of physicians by our Schools of Medicine is included. Information about ACGME accredited postgraduate cardiovascular training programs conducted in Puerto Rico is presented. Data concerning the prevalence of hypertension, diabetes mellitus, overweight and obesity obtained by BRFSS in presented.

  6. Recent Advances in Dengue: Relevance to Puerto Rico

    Science.gov (United States)

    Noyd, David H.; Sharp, Tyler M.

    2015-01-01

    Dengue represents an increasingly important public health challenge in Puerto Rico, with recent epidemics in 2007, 2010, and 2012–2013. Although recent advances in dengue vaccine development offer hope for primary prevention, the role of health professionals in the diagnosis and management of dengue patients is paramount. Case definitions for dengue, dengue with warning signs, and severe dengue provide a framework to guide clinical decision-making. Furthermore, the differentiation between dengue and other acute febrile illnesses, such as leptospirosis and chikungunya, is necessary for the appropriate diagnosis and management of cases. An understanding of dengue epidemiology and surveillance in Puerto Rico provides context for clinicians in epidemic and non-epidemic periods. This review aims to improve health professionals’ ability to diagnose dengue, and as highlight the relevance of recent advances in dengue prevention and management in Puerto Rico. PMID:26061055

  7. [Legal secrecy: abortion in Puerto Rico from 1937 to 1970].

    Science.gov (United States)

    Marchand-Arias, R E

    1998-03-01

    The essay discusses abortion in Puerto Rico from 1937 to 1970, concentrating in its legal status as well as its social practice. The research documents the contradictions between the legality of the procedure and a social practice characterized by secrecy. The essay discusses the role of the Clergy Consultation Service on Abortion in promoting the legal practice of absortion in Puerto Rico. It also discusses the ambivalent role of medical doctors who, despite being legally authorized to perform abortions to protect the life and health of women, refused to perform the procedure arguing abortion was illegal. The essay concludes with a brief discussion on perceptions of illegality regarding abortion, emphasizing the contradictions between the practice of abortion and that of sterilization in Puerto Rico.

  8. Lessons Learned from the Puerto Rico Battery Energy Storage System

    Energy Technology Data Exchange (ETDEWEB)

    Boyes, John D.; De Anda, Mindi Farber; Torres, Wenceslao

    1999-08-11

    The Puerto Rico Electric Power Authority (PREPA) installed a battery energy storage system in 1994 at a substation near San Juan, Puerto Rico. It was patterned after two other large energy storage systems operated by electric utilities in California and Germany. The Puerto Rico facility is presently the largest operating battery storage system in the world and has successfully provided frequency control, voltage regulation, and spinning reseme to the Caribbean island. The system further proved its usefulness to the PREPA network in the fall of 1998 in the aftermath of Hurricane Georges. However, the facility has suffered accelerated cell failures in the past year and PREPA is committed to restoring the plant to full capacity. This represents the first repowering of a large utility battery facility. PREPA and its vendors and contractors learned many valuable lessons during all phases of project development and operation, which are summarized in this paper.

  9. Dispersion Decay and Scattering Theory

    CERN Document Server

    Komech, Alexander

    2012-01-01

    A simplified, yet rigorous treatment of scattering theory methods and their applications Dispersion Decay and Scattering Theory provides thorough, easy-to-understand guidance on the application of scattering theory methods to modern problems in mathematics, quantum physics, and mathematical physics. Introducing spectral methods with applications to dispersion time-decay and scattering theory, this book presents, for the first time, the Agmon-Jensen-Kato spectral theory for the Schr?dinger equation, extending the theory to the Klein-Gordon equation. The dispersion decay plays a crucial role i

  10. Velocity Dispersions Across Bulge Types

    International Nuclear Information System (INIS)

    Fabricius, Maximilian; Bender, Ralf; Hopp, Ulrich; Saglia, Roberto; Drory, Niv; Fisher, David

    2010-01-01

    We present first results from a long-slit spectroscopic survey of bulge kinematics in local spiral galaxies. Our optical spectra were obtained at the Hobby-Eberly Telescope with the LRS spectrograph and have a velocity resolution of 45 km/s (σ*), which allows us to resolve the velocity dispersions in the bulge regions of most objects in our sample. We find that the velocity dispersion profiles in morphological classical bulge galaxies are always centrally peaked while the velocity dispersion of morphologically disk-like bulges stays relatively flat towards the center--once strongly barred galaxies are discarded.

  11. Leprosy in Puerto Rico: insight into the new millennia.

    Science.gov (United States)

    Valentín, Diana C; Candelario, Nicole; Carrasquillo, Osward Y; Figueroa, Luz; Sánchez, Jorge L

    2017-04-01

    Leprosy, or Hansen's disease, is a chronic infectious disease caused by the bacillus Mycobacterium leprae. In 2000, the World Health Organization (WHO) defined the elimination of the disease as a global prevalence of less than one case per 10,000 population. However, disease transmission is an ongoing worldwide public health concern, as evidenced by the more than 220,000 new cases diagnosed each year. This study is an update of the incidence and prevalence of leprosy in Puerto Rico for the period of 2000-2014. A retrospective analysis of data was obtained from the Tropical Disease Clinic (TDC) of the University of Puerto Rico School of Medicine. Sixty-three new cases of leprosy are detailed in this study. Disease incidence and prevalence were 1.65 and 5.26 per 100,000 inhabitants (of the island of Puerto Rico), respectively, and an average of 4.2 new cases per year. Most of the male patients in the study suffered from lepromatous leprosy (P = 0.026). In all, 47 (74.6%) patients had been born in Puerto Rico, and 29 (46%) had an affected family member or were in close contact with someone with leprosy. Compared to those of previous studies, these results demonstrate a decrease in both the incidence and prevalence of leprosy in Puerto Rico over the past 15 years. The relatively high prevalence of leprosy in Puerto Rico means that it remains endemic on the island. Concerted efforts must be undertaken to achieve the goal of the elimination of this old and stigmatized disease. © 2017 The International Society of Dermatology.

  12. ??ndice num??rico de un espacio de Banach

    OpenAIRE

    Mart??n Su??rez, Miguel

    2000-01-01

    El ??ndice num??rico de un espacio de Banach se define como la mayor constante de equivalencia entre el radio num??rico y la norma usual en el ??lgebra de todos los operadores lineales y continuos sobre ??l. Este concepto fue introducido por G. Lumer en 1968, y estudiado por matem??ticos como F. Bonsall, J. Duncan, C. McGregor, J. Pryce y A. White. En la tesis se hace un estudio sistem??tica de este concepto. Por una parte, se estudia el comportamiento del ??ndice num??ri...

  13. Plasma rico en plaquetas en pacientes con gonartrosis

    OpenAIRE

    Álvarez López, Alejandro; Ortega González, Carlos; García Lorenzo, Yenima; Arias Sifontes, Joanka; Ruiz de Villa Suárez, Abel

    2013-01-01

    Fundamento: la aplicación del plasma rico en plaquetas se ha convertido en una modalidad de tratamiento para pacientes con gonartrosis, tanto de forma aislada como en combinación con otros procedimientos. Objetivo: actualizar al personal médico sobre aspectos esenciales relacionados con la aplicación del plasma rico en plaquetas en pacientes con gonartrosis. Método: se realizó una revisión bibliográfica de un total de 300 artículos originales publicados en Pubmed, Hinari y Medline, mediante e...

  14. What Causes Animals to Disperse?

    Indian Academy of Sciences (India)

    research involving animal behaviour and ecology for a very long time. ... shall examine two different types of dispersals that occur, try to understand the ... finally look at some practical methods through which the phe- ..... further qualitative or.

  15. Birefringent dispersive FDTD subgridding scheme

    OpenAIRE

    De Deckere, B; Van Londersele, Arne; De Zutter, Daniël; Vande Ginste, Dries

    2016-01-01

    A novel 2D finite difference time domain (FDTD) subgridding method is proposed, only subject to the Courant limit of the coarse grid. By making mu or epsilon inside the subgrid dispersive, unconditional stability is induced at the cost of a sparse, implicit set of update equations. By only adding dispersion along preferential directions, it is possible to dramatically reduce the rank of the matrix equation that needs to be solved.

  16. Dispersion engineering for integrated nanophotonics

    CERN Document Server

    Vanbésien, Olivier

    2014-01-01

    This book shows how dispersion engineering in two dimensional dielectric photonic crystals can provide new effects for the precise control of light propagation for integrated nanophotonics.Dispersion engineering in regular and graded photonic crystals to promote anomalous refraction effects is studied from the concepts to experimental demonstration via nanofabrication considerations. Self collimation, ultra and negative refraction, second harmonic generation, mirage and invisibility effects which lead to an unprecedented control of light propagation at the (sub-)wavelength scale for the

  17. Dispersion coefficients for coastal regions

    International Nuclear Information System (INIS)

    MacRae, B.L.; Kaleel, R.J.; Shearer, D.L.

    1983-03-01

    The Nuclear Regulatory Commission (NRC) has undertaken an extensive atmospheric dispersion research and measurement program from which it is intended will emerge improved predictive techniques for employment in licensing decisions and for emergency planning and response. Through this program the NRC has conducted field measurement programs over a wide range of geographic and topographic locations, and are using the acquired tracer and meteorological measurements to evaluate existing dispersion models and prediction techniques, and to develop new techniques when necessary

  18. La política social. Presupuestos teóricos y horizonte histórico

    Directory of Open Access Journals (Sweden)

    Sergio Fernández Riquelme

    2011-07-01

    Full Text Available En este trabajo proponemos una revisión de los presupuestos teóricos de la Política Social, como ciencia normativa y autónoma, en su devenir histórico, su pluralidad doctrinal y su diversidad institucional, en especial del actual modelo del Estado del Bienestar. Asimismo, abordamos el impacto en la misma de una nueva cuestión social, el desarrollo humano integral, a inicios del siglo XXI, ante fenómenos como la “Europa social”, la sociedad del bienestar y la globalización.

  19. Madagascar sheds new light on the molecular systematics and biogeography of grammitid ferns: New unexpected lineages and numerous long-distance dispersal events.

    Science.gov (United States)

    Bauret, Lucie; Gaudeul, Myriam; Sundue, Michael A; Parris, Barbara S; Ranker, Tom A; Rakotondrainibe, France; Hennequin, Sabine; Ranaivo, Jaona; Selosse, Marc-André; Rouhan, Germinal

    2017-06-01

    Based on a worldwide phylogenetic framework filling the taxonomic gap of Madagascar and surrounding islands of the Western Indian Ocean (WIO), we revisited the systematics of grammitid fern species (Polypodiaceae). We also investigated the biogeographic origin of the extant diversity in Madagascar and estimated the relative influence of vicariance, long-distance dispersals (LDD) and in situ diversification. Phylogenetic inferences were based on five plastid DNA regions (atpB, rbcL, rps4-trnS, trnG-trnR, trnL-trnF) and the most comprehensive taxonomic sampling ever assembled (224 species belonging to 31 out of 33 recognized grammitids genera). 31 species from Madagascar were included representing 87% of the described diversity and 77% of the endemics. Our results confirmed a Paleotropical clade nested within an amphi-Atlantic grade. In addition, we identified three new major clades involving species currently belonging to Grammitis s.l., Ctenopterella and Enterosora. We resolved for the first time Grammitis s.s. as monophyletic, and Ctenopterella (newly tested here) and Enterosora as polyphyletic. The Neotropical genus Moranopteris was shown to also occur in Madagascar through a newly discovered species. Most importantly, we suggest a >30% inflation of the species number in the WIO due to the hidden diversity in >10 cryptic lineages, best explained by high morphological homoplasy. Molecular dating and ancestral areas reconstruction allowed identifying the Neotropics as the predominant source of LDD to the African-WIO region, with at least 12 colonization events within the last 20Ma. Repeated eastward migrations may be explained by transoceanic westerly winds transporting the dust-like spores. Tropical Asia s.l. would also have played a (minor) role through one dispersal event to Madagascar at the end of the Oligocene. Last, within the complex Malagasy region made of a mosaic of continental and oceanic islands located close to the African continent, we showed that

  20. Shapefile of the bathymetric contours of Lago Lucchetti, Puerto Rico, September 2013-May 2014

    Data.gov (United States)

    Department of the Interior — The U.S. Geological Survey conducted a sedimentation survey of Lago Lucchetti, Yauco, Puerto Rico, in 2013–14 in cooperation with the Puerto Rico Aqueduct and Sewer...

  1. Contributions to the study of gasteromycetes of Puerto Rico

    Science.gov (United States)

    Angel M. Nieves-Rivera; D. Jean. Lodge; Orson K. Miller

    1998-01-01

    Battarrea stevenii and Tulostoma cf. meridionale, two cosmopolitan taxa are reported as new records for Puerto Rico. Both species were collected from the same disturbed subtropical dry forested area. A partial checklist of the taxa of macromycetes collected from Boquer*on Commonwealth- and Laguna Cartagena National Wildlife Refuges is also provided.

  2. Relations between Study and Employment: Music Graduates in Puerto Rico

    Science.gov (United States)

    Latorre, Ileana S.; Lorenzo, Oswaldo

    2013-01-01

    Higher education programs in Puerto Rico include undergraduate degrees in music, music education, composition, popular music, jazz and Caribbean music, and, most recently, a master’s degree in music education. However, little is known about what music graduates do after concluding college. Do they work in music-related areas? Are they satisfied…

  3. Guide to the ecological systems of Puerto Rico

    Science.gov (United States)

    G. Miller; A.E. Lugo

    2009-01-01

    This guide is an introduction to the ecological systems of Puerto Rico. It covers the diversity of ecological systems in the island, their most common plant and animal species, and salient aspects of their structure and functioning. Terrestrial, wetland, coastal, and marine ecosystems are included, as well as agroforest and urban systems. The discussion of the...

  4. Disinfection Alternatives for Small Communities in Puerto Rico

    Science.gov (United States)

    Disinfection Alternatives for Small Communities in Puerto Rico Craig Patterson1, Graciela Ramirez Toro2, Harvey Minnigh2, Cristina Maldonado3, and Rajib Sinha4 1U.S. EPA Office of Research and Development, 2Centro de Educación, Conservación e Interpretación Ambiental (CECIA),...

  5. Food resource partitioning inb syntopic nectarivorous bats on Puerto Rico

    Science.gov (United States)

    We analyzed stable isotopes (δ13C, δ15N) to estimate the importance of plants and insects to the diet of two nectar-feeding bats on Puerto Rico, the brown flower bat (Erophylla bombifrons) and the Greater Antillean long-tongued bat (Monophyllus redmani). Concentrations of stable ...

  6. Convective mixing by internal waves in the Puerto Rico Trench

    NARCIS (Netherlands)

    van Haren, H.; Gostiaux, L.

    2016-01-01

    A2.4 km long deep-sea mooringwas deployed for 14 months in the Puerto Rico Trench, the deepestpart of the Atlantic Ocean. Below its top buoyancy package, the mooring line held a 200 m long stringof high-resolution temperature sensors and a current meter. Over the instrumented range between6,004 and

  7. Diversity of Papaya ringspot virus isolates in Puerto Rico

    Science.gov (United States)

    Papaya ringspot virus (PRSV) devastates papaya production worldwide. In Puerto Rico, papaya fields can be completely infected with PRSV within a year of planting. Information about the diversity of the Puerto Rican PRSV population is relevant in order to establish a control strategy in the island. T...

  8. Trailblazing the Carbon Cycle of Tropical Forests from Puerto Rico

    Science.gov (United States)

    Sandra Brown; Ariel Lugo

    2017-01-01

    We review the literature that led to clarifying the role of tropical forests in the global carbon cycle from a time when they were considered sources of atmospheric carbon to the time when they were found to be atmospheric carbon sinks. This literature originates from work conducted by US Forest Service scientists in Puerto Rico and their collaborators. It involves the...

  9. Diameter growth of subtropical trees in Puerto Rico

    Science.gov (United States)

    Thomas J. Brandeis

    2009-01-01

    Puerto Rico’s forests consist of young, secondary stands still recovering from a long history of island-wide deforestation that largely abated in the mid-20th century. Limited knowledge about growth rates of subtropical tree species in these forests makes it difficult to accurately predict forest yield, biomass accumulation, and carbon...

  10. 76 FR 47286 - Puerto Rico Disaster Number PR-00013

    Science.gov (United States)

    2011-08-04

    ... SMALL BUSINESS ADMINISTRATION Disaster Declaration 12699 and 12700 Puerto Rico Disaster Number PR-00013 AGENCY: U.S. Small Business Administration. ACTION: Amendment 1. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the State of Puerto...

  11. 76 FR 59178 - Puerto Rico Disaster Number PR-00015

    Science.gov (United States)

    2011-09-23

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12770 and 12771] Puerto Rico Disaster Number PR-00015 AGENCY: U.S. Small Business Administration. ACTION: Amendment 2. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the...

  12. 76 FR 63699 - Puerto Rico Disaster Number PR-00015

    Science.gov (United States)

    2011-10-13

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12770 and 12771] Puerto Rico Disaster Number PR-00015 AGENCY: U.S. Small Business Administration. ACTION: Amendment 4. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the...

  13. 75 FR 76517 - Puerto Rico Disaster Number PR-00012

    Science.gov (United States)

    2010-12-08

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12368 and 12369] Puerto Rico Disaster Number PR-00012 AGENCY: U.S. Small Business Administration. ACTION: Amendment 2. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the...

  14. 76 FR 62133 - Puerto Rico Disaster Number PR-00015

    Science.gov (United States)

    2011-10-06

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12770 and 12771] Puerto Rico Disaster Number PR-00015 AGENCY: U.S. Small Business Administration. ACTION: Amendment 3. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance only for the...

  15. 76 FR 56861 - Puerto Rico Disaster Number PR-00015

    Science.gov (United States)

    2011-09-14

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12770 and 12771] Puerto Rico Disaster Number PR-00015 AGENCY: U.S. Small Business Administration. ACTION: Amendment 1. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the...

  16. Sistema de Vigilancia de Influenza de Puerto Rico |

    Science.gov (United States)

    Oral Salud por Poblaciones Salud Sexual Suicidio Tabaquismo Vacunación Violación/Agresión Sexual Rico VIH Publicaciones sobre la Salud Otras Publicaciones Registros Suicidio Tuberculosis Centro de Suicidio Tuberculosis Recent Ávisos Públicos Reglamentación Informe de Casos del Síndrome de Guillain

  17. Urban and rural land use in Puerto Rico

    Science.gov (United States)

    Sebastian Martinuzzi; William A. Gould; Olga M. Ramos Gonzalez; Maya Quinones; Michael E. Jimenez

    2008-01-01

    We have developed three land use regions for Puerto Rico: Urban, Suburban, and Rural (Gould et al. 2008; Martinuzzi et al. 2007). These three regions can also be considered urban, densely-populated rural, and sparsely-populated rural or as urban and wildland with a wildland-urban interface. The suburban use is the most dynamic in terms of population growth and land...

  18. English Acquisition in Puerto Rico: Teachers' Insights

    Science.gov (United States)

    Eisenstein Ebsworth, Miriam; Ebsworth, Timothy John; Cai, Chencen

    2018-01-01

    Acquiring English in Puerto Rico involves the perceived advantages of bilingualism in contact with socio-political and economic forces that encourage and constrain the development of a population that is bilingual and biliterate in Spanish and English. Using a mixed design we report the perspectives of 86 experienced English teachers on the…

  19. Land Use, Conservation, Forestry, and Agriculture in Puerto Rico

    Science.gov (United States)

    William A. Gould; Frank H. Wadsworth; Maya Quinones; Stephen J. Fain; Nora L. Álvarez-Berríos

    2017-01-01

    Global food security concerns emphasize the need for sustainable agriculture and local food production. In Puerto Rico, over 80 percent of food is imported, and local production levels have reached historical lows. Efforts to increase local food production are driven by government agencies, non-government organizations, farmers, and consumers. Integration of geographic...

  20. Lichenological studies in Puerto Rico: history and current status

    Science.gov (United States)

    Joel A. Mercado-Diaz; Eugenio Santiago-Valentin

    2010-01-01

    European scientists initiated lichenology in Puerto Rico in the 19th century. Activity of the discipline increased notably on the island during the first three decades of the 20th century, primarily by the field explorations and publications of the New York Botanical Garden scientists and associates (A. A. Heller, N. L. and E. G. Britton, L. W. Riddle), and by the work...

  1. Earthworm communities along an elevation gradient in Northeastern Puerto Rico.

    Science.gov (United States)

    Grizelle Gonzalez; Emerita Garcia; Veronica Cruz; Sonia Borges; Marcela Zalamea; Maria M. Rivera

    2007-01-01

    In this study, we describe earthworm communities along an elevation gradient of eight forest types in Northeastern Puerto Rico, and determine whether their abundance, biomass and/or diversity is related to climatic, soil physical/chemical and/or biotic characteristics. We found that the density, biomass, and diversity of worms varied significantly among forest types....

  2. 76 FR 60513 - Puerto Rico; Emergency and Related Determinations

    Science.gov (United States)

    2011-09-29

    ... resulting from Hurricane Irene beginning on August 21, 2011, and continuing, are of sufficient severity and... adversely affected by this declared emergency: All 78 municipalities in the Commonwealth of Puerto Rico for... Unemployment Assistance (DUA); 97.046, Fire Management Assistance Grant; 97.048, Disaster Housing Assistance to...

  3. The green areas of San Juan, Puerto Rico

    Science.gov (United States)

    O.M. Ramos-Gonzalez

    2014-01-01

    Green areas, also known as green infrastructure or urban vegetation, are vital to urbanites for their critical roles in mitigating urban heat island effects and climate change and for their provision of multiple ecosystem services and aesthetics. Here, I provide a high spatial resolution snapshot of the green cover distribution of the city of San Juan, Puerto Rico, by...

  4. 40 CFR 81.77 - Puerto Rico Air Quality Control Region.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Puerto Rico Air Quality Control Region... PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.77 Puerto Rico Air Quality Control Region. The Puerto Rico Air Quality Control Region...

  5. 77 FR 48504 - Proposed Information Collection; Comment Request; Economic Value of Puerto Rico's Coral Reef...

    Science.gov (United States)

    2012-08-14

    ... Collection; Comment Request; Economic Value of Puerto Rico's Coral Reef Ecosystems for Recreation-Tourism... the market and non-market economic values of Puerto Rico's coral reef ecosystems. Estimates will be... Puerto Rico's coral reef ecosystems. The required information is to conduct focus groups to help in...

  6. 75 FR 1543 - Approval and Promulgation of Implementation Plans; Puerto Rico; Guaynabo PM10

    Science.gov (United States)

    2010-01-12

    ... Control of Atmospheric Pollution. On July 15, 2009, the Puerto Rico Environmental Quality Board submitted... Control of Atmospheric Pollution Commonwealth Puerto Rico regulations effective date EPA approval date... analysis and revisions to Rules 102 and 423 of the Puerto Rico Regulation for the Control of Atmospheric...

  7. 42 CFR 412.374 - Payments to hospitals located in Puerto Rico.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Payments to hospitals located in Puerto Rico. 412... Payment System for Inpatient Hospital Capital Costs Special Rules for Puerto Rico Hospitals § 412.374 Payments to hospitals located in Puerto Rico. (a) FY 1998 through FY 2004. Payments for capital-related...

  8. 5 CFR 532.275 - Special wage schedules for ship surveyors in Puerto Rico.

    Science.gov (United States)

    2010-01-01

    ... in Puerto Rico. 532.275 Section 532.275 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL... schedules for ship surveyors in Puerto Rico. (a) The Department of Defense shall establish special wage schedules for nonsupervisory ship surveyors and supervisory ship surveyors in Puerto Rico. (b) Rates shall...

  9. 42 CFR 412.370 - General provisions for hospitals located in Puerto Rico.

    Science.gov (United States)

    2010-10-01

    ... Prospective Payment System for Inpatient Hospital Capital Costs Special Rules for Puerto Rico Hospitals § 412.370 General provisions for hospitals located in Puerto Rico. Except as provided in § 412.374, hospitals located in Puerto Rico are subject to the rules in this subpart governing the prospective payment...

  10. 77 FR 52310 - Expansion of Foreign-Trade Zone 61, San Juan, Puerto Rico

    Science.gov (United States)

    2012-08-29

    ... 61, San Juan, Puerto Rico Pursuant to its authority under the Foreign-Trade Zones Act of June 18... Order: Whereas, the Puerto Rico Trade and Export Company, grantee of Foreign-Trade Zone 61, submitted an application to the Board for authority to expand FTZ 61 to include a site in Aguadilla, Puerto Rico, adjacent...

  11. 7 CFR 318.13-24 - Sweet potatoes from Puerto Rico.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Sweet potatoes from Puerto Rico. 318.13-24 Section 318... Articles From Hawaii and the Territories § 318.13-24 Sweet potatoes from Puerto Rico. Sweet potatoes from Puerto Rico may be moved interstate to Atlantic Coast ports north of and including Baltimore, MD, under...

  12. 27 CFR 19.396 - Spirits removed for shipment to Puerto Rico.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Spirits removed for shipment to Puerto Rico. 19.396 Section 19.396 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO... § 19.396 Spirits removed for shipment to Puerto Rico. Spirits removed for shipment to Puerto Rico with...

  13. 26 CFR 1.933-1 - Exclusion of certain income from sources within Puerto Rico.

    Science.gov (United States)

    2010-04-01

    ... Puerto Rico. 1.933-1 Section 1.933-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE... Exclusion of certain income from sources within Puerto Rico. (a) General rule. (1) An individual (whether a United States citizen or an alien), who is a bona fide resident of Puerto Rico during the entire taxable...

  14. 47 CFR 73.1210 - TV/FM dual-language broadcasting in Puerto Rico.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false TV/FM dual-language broadcasting in Puerto Rico...-language broadcasting in Puerto Rico. (a) For the purpose of this section, dual-language broadcasting shall... a different language. (b) Television and Class A television licensees in Puerto Rico may enter into...

  15. 42 CFR 412.220 - Special treatment of certain hospitals located in Puerto Rico.

    Science.gov (United States)

    2010-10-01

    ... Puerto Rico. 412.220 Section 412.220 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT... SERVICES Prospective Payment System for Inpatient Operating Costs for Hospitals Located in Puerto Rico § 412.220 Special treatment of certain hospitals located in Puerto Rico. Subpart G of this part sets...

  16. 78 FR 9884 - Approval of Subzone Status; Zimmer Manufacturing BV; Ponce, Puerto Rico

    Science.gov (United States)

    2013-02-12

    ...; Zimmer Manufacturing BV; Ponce, Puerto Rico Pursuant to its authority under the Foreign-Trade Zones Act... subzone at the facility of Zimmer Manufacturing BV located in Ponce, Puerto Rico (FTZ Docket B-81-2012... hereby approves subzone status at the facility of Zimmer Manufacturing BV located in Ponce, Puerto Rico...

  17. 19 CFR 7.2 - Insular possessions of the United States other than Puerto Rico.

    Science.gov (United States)

    2010-04-01

    ... than Puerto Rico. 7.2 Section 7.2 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF... NAVAL STATION § 7.2 Insular possessions of the United States other than Puerto Rico. (a) Insular possessions of the United States other than Puerto Rico are also American territory but, because those insular...

  18. 42 CFR 412.204 - Payment to hospitals located in Puerto Rico.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Payment to hospitals located in Puerto Rico. 412... Payment System for Inpatient Operating Costs for Hospitals Located in Puerto Rico § 412.204 Payment to hospitals located in Puerto Rico. (a) FY 1988 through FY 1997. For discharges occurring on or after October...

  19. 78 FR 13625 - Approval of Subzone Status; Sea World, Inc.; Guaynabo, Puerto Rico

    Science.gov (United States)

    2013-02-28

    ... World, Inc.; Guaynabo, Puerto Rico On December 12, 2012, the Executive Secretary of the Foreign-Trade Zones (FTZ) Board docketed an application submitted by the Puerto Rico Trade & Export Company, grantee... Sea World, Inc., in Guaynabo, Puerto Rico. The application was processed in accordance with the FTZ...

  20. Lepidoptera outbreaks in response to successional changes after the passage of Hurricane Hugo in Puerto Rico Rico

    Science.gov (United States)

    J.A. Torres

    1992-01-01

    Fifteen species of Lepidoptera occurred in large numbers in spring and early summer after the passage of Hurricane Hugo over the north-east of Puerto Rico. Spodoptera eridania (Noctuidae) was the most common of the larvae and fed on 56 plant species belonging to 31 families. All the Lepidoptera fed on early successional vegetation. Some of the plants represent new host...

  1. Atmospheric dispersion of radioactive materials

    International Nuclear Information System (INIS)

    Chino, Masamichi

    1988-01-01

    The report describes currently available techniques for predicting the dispersion of accidentally released radioactive materials and techniques for visualization using computer graphics. A simulation study is also made on the dispersion of radioactive materials released from the Chernobyl plant. The simplest models include the Gauss plume model and the puff model, which cannot serve to analyze the effects of the topography, vertical wind shear, temperature inversion layer, etc. Numerical analysis methods using advection and dispersion equations are widely adopted for detailed evaluation of dispersion in an emergency. An objective analysis model or a hydrodynamical model is often used to calculate the air currents which are required to determine the advection. A small system based on the puff model is widely adopted in Europe, where the topography is considered to have only simple effects. A more sophisticated large-sized system is required in nuclear facilities located in an area with more complex topographic features. An emergency system for dispersion calculation should be equipped with a graphic display to serve for quick understanding of the radioactivity distribution. (Nogami, K.)

  2. Evaluation of particle dispersal from mining and milling operations using lead isotopic fingerprinting techniques, Rio Pilcomayo Basin, Bolivia

    International Nuclear Information System (INIS)

    Miller, Jerry R.; Lechler, Paul J.; Mackin, Gail; Germanoski, Dru; Villarroel, Lionel F.

    2007-01-01

    Mining and milling of ores from the Cerro Rico de Potosi precious metal-polymetallic tin deposits of Bolivia have led to severe contamination of water and sediments of the Rio Pilcomayo drainage system. Lead (Pb) isotopic data were used in this study to first document downstream dispersal patterns of Pb contaminated sediment within the channel of the Rio Pilcomayo, and then to determine the relative contribution of Pb from Cerro Rico within alluvial terrace soils that are used for agriculture. The concentration and isotopic composition of Pb within channel bed sediments differed significantly between 2000, 2002, and 2004. These differences presumably reflect changes in the type of ore mined and milled at Cerro Rico, and alterations in dispersal and grain-size dilution mechanisms associated with interannual variations in rainfall and runoff. Within agricultural terrace soils, both Pb concentrations and the percentage of Pb from Cerro Rico: (1) semi-systematically decrease downstream, (2) were found to decrease with terrace height above the channel, and (3) reflect the use of contaminated irrigation water. In upstream reaches (within 30 km of the mills), Pb from mining represents the most significant Pb source, accounting for more than 80% of Pb in the examined agricultural fields. At Sotomayor, located approximately 170 km from the mills, the relative contribution of Pb from Cerro Rico is highly variable between fields, but can be significant, ranging from approximately 15% to 35%. The analysis demonstrates that Pb isotopic ratios can be used to effectively trace contaminated particles through river systems and into adjacent alluvial soils, even where multiple Pb sources exist and Pb concentrations are similar to background values

  3. Aspectos teóricos do pensamento histórico de Quentin Skinner

    Directory of Open Access Journals (Sweden)

    Marcos Antônio Lopes

    2011-06-01

    Full Text Available Após retratar o surgimento da Escola histórica do pensamento político de Cambridge, o foco da análise é centrado no desenvolvimento de alguns dos pressupostos teóricos elaborados por um de seus mais expressivos cultores: Quentin Skinner. Sem me ocupar com a exposição de "modelos alternativos" de interpretação de textos ou com a análise das críticas dirigidas ao contextualismo linguístico, passo em revista apenas os elementos que compõem o cerne da teoria interpretativa de textos políticos, conforme formulada pelo historiador inglês. Nesse sentido, discuto os pressupostos que o autor, ainda hoje, parece julgar úteis àqueles que se ocupam em perceber, nos clássicos da política, as diferenças e as singularidades que apartam de nós sistemas de crenças e vocabulários normativos de sociedades políticas perdidas em tempos remotos.After depicting the birth of the Cambridge historical school of political thought, the focus of the analysis is placed on the development of some theoretical assumptions created by one of its most representative followers: Quentin Skinner. Unconcerned with the exposition of "alternative models" for text interpretations or with the analysis of the criticism directed to linguistic contextualism, this study revises the key elements of the interpretative theory of political texts, according to the English historian. In this sense, we discuss the assumptions that the author, even today, seems to deem useful to those who are interested in noticing in classic Politics the uniqueness which set us apart from the system of beliefs and normative vocabulary of the political societies lost in remote times.

  4. Micromixer based on Taylor dispersion

    International Nuclear Information System (INIS)

    Yang, H; Nguyen, N-T; Huang, X

    2006-01-01

    This paper reports an analytical model, the fabrication and the characterization of a polymeric micromixer based on Taylor dispersion. Due to the distributed velocity field over the channel cross section, the effective dispersion in axial direction in a microchannel is much stronger than the pure molecular diffusion. In our work, squential segmentation was used in the micromixer for improving mixing in a microchannel. The micromixer was designed and fabricated based on lamination of five 100-μm-thick polymer sheets. Rubber valve seats were embedded between the forth and the fifth layers. The polymer layers were machined using a CO 2 laser. The lamination of the five layers was carried out by a commercial hot laminator (Aurora LM-450HC). External solenoid actuators are used for closing the valves at the mixer inlets. The experimental results confirm the effect of Taylor dispersion. Mixing ratio can be adjusted by pulse width modulation of the control signal of the solenoids

  5. Improving IUE High Dispersion Extraction

    Science.gov (United States)

    Lawton, Patricia J.; VanSteenberg, M. E.; Massa, D.

    2007-01-01

    We present a different method to extract high dispersion International Ultraviolet Explorer (IUE) spectra from the New Spectral Image Processing System (NEWSIPS) geometrically and photometrically corrected (SI HI) images of the echellogram. The new algorithm corrects many of the deficiencies that exist in the NEWSIPS high dispersion (SIHI) spectra . Specifically, it does a much better job of accounting for the overlap of the higher echelle orders, it eliminates a significant time dependency in the extracted spectra (which can be traced to the background model used in the NEWSIPS extractions), and it can extract spectra from echellogram images that are more highly distorted than the NEWSIPS extraction routines can handle. Together, these improvements yield a set of IUE high dispersion spectra whose scientific integrity is sign ificantly better than the NEWSIPS products. This work has been supported by NASA ADP grants.

  6. STELLAR MASS DEPENDENT DISK DISPERSAL

    International Nuclear Information System (INIS)

    Kennedy, Grant M.; Kenyon, Scott J.

    2009-01-01

    We use published optical spectral and infrared (IR) excess data from nine young clusters and associations to study the stellar mass dependent dispersal of circumstellar disks. All clusters older than ∼3 Myr show a decrease in disk fraction with increasing stellar mass for solar to higher mass stars. This result is significant at about the 1σ level in each cluster. For the complete set of clusters we reject the null hypothesis-that solar and intermediate-mass stars lose their disks at the same rate-with 95%-99.9% confidence. To interpret this behavior, we investigate the impact of grain growth, binary companions, and photoevaporation on the evolution of disk signatures. Changes in grain growth timescales at fixed disk temperature may explain why early-type stars with IR excesses appear to evolve faster than their later-type counterparts. Little evidence that binary companions affect disk evolution suggests that photoevaporation is the more likely mechanism for disk dispersal. A simple photoevaporation model provides a good fit to the observed disk fractions for solar and intermediate-mass stars. Although the current mass-dependent disk dispersal signal is not strong, larger and more complete samples of clusters with ages of 3-5 Myr can improve the significance and provide better tests of theoretical models. In addition, the orbits of extra-solar planets can constrain models of disk dispersal and migration. We suggest that the signature of stellar mass dependent disk dispersal due to photoevaporation may be present in the orbits of observed extra-solar planets. Planets orbiting hosts more massive than ∼1.6 M sun may have larger orbits because the disks in which they formed were dispersed before they could migrate.

  7. Dispersion of multi-walled carbon nanotubes in biocompatible dispersants

    International Nuclear Information System (INIS)

    Piret, J.-P.; Detriche, S.; Vigneron, R.; Vankoningsloo, S.; Rolin, S.; Mejia Mendoza, J. H.; Masereel, B.; Lucas, S.; Delhalle, J.; Luizi, F.; Saout, C.; Toussaint, O.

    2010-01-01

    Owing to their phenomenal electrical and mechanical properties, carbon nanotubes (CNT) have been an area of intense research since their discovery in 1991. Different applications for these nanoparticles have been proposed, among others, in electronics and optics but also in the medical field. In parallel, emerging studies have suggested potential toxic effects of CNT while others did not, generating some conflicting outcomes. These discrepancies could be, in part, due to different suspension approaches used and to the agglomeration state of CNT in solution. In this study, we described a standardized protocol to obtain stable CNT suspensions, using two biocompatible dispersants (Pluronic F108 and hydroxypropylcellulose) and to estimate the concentration of CNT in solution. CNT appear to be greatly individualized in these two dispersants with no detection of remaining bundles or agglomerates after sonication and centrifugation. Moreover, CNT remained perfectly dispersed when added to culture medium used for in vitro cell experiments. We also showed that Pluronic F108 is a better dispersant than hydroxypropylcellulose. In conclusion, we have developed a standardized protocol using biocompatible surfactants to obtain reproducible and stable multi-walled carbon nanotubes suspensions which can be used for in vitro or in vivo toxicological studies.

  8. DIMO, a plant dispersal model

    NARCIS (Netherlands)

    Wamelink, G.W.W.; Jochem, R.; Greft, van der J.G.M.; Franke, J.; Malinowska, A.H.; Geertsema, W.; Prins, A.H.; Ozinga, W.A.; Hoek, van der D.C.J.; Grashof-Bokdam, C.J.

    2014-01-01

    Due to human activities many natural habitats have become isolated. As a result the dispersal of many plant species is hampered. Isolated populations may become extinct and have a lower probability to become reestablished in a natural way. Moreover, plant species may be forced to migrate to new

  9. A generalized advection dispersion equation

    Indian Academy of Sciences (India)

    This paper examines a possible effect of uncertainties, variability or heterogeneity of any dynamic system when being included in its evolution rule; the notion is illustrated with the advection dispersion equation, which describes the groundwater pollution model. An uncertain derivative is defined; some properties of.

  10. Ability Dispersion and Team Performance

    DEFF Research Database (Denmark)

    Hoogendoorn, Sander; Parker, Simon C.; Van Praag, Mirjam

    What is the effect of dispersed levels of cognitive ability of members of a (business) team on their team's performance? This paper reports the results of a field experiment in which 573 students in 49 teams start up and manage real companies under identical circumstances. We ensured exogenous va...

  11. Statistical description of turbulent dispersion

    NARCIS (Netherlands)

    Brouwers, J.J.H.

    2012-01-01

    We derive a comprehensive statistical model for dispersion of passive or almost passive admixture particles such as fine particulate matter, aerosols, smoke and fumes, in turbulent flow. The model rests on the Markov limit for particle velocity. It is in accordance with the asymptotic structure of

  12. Magnetic exciton dispersion in praseodymium

    DEFF Research Database (Denmark)

    Rainford, B. D.; Houmann, Jens Christian Gylden

    1971-01-01

    Measurements of the dispersion of magnetic excitons have been made in a single crystal of praseodymium metal using inelastic neutron scattering. A preliminary analysis of the data yields the first detailed information about the exchange interactions and the crystal field splittings in the light...... rare-earth metals....

  13. On Dispersion in Visual Photoreceptors

    NARCIS (Netherlands)

    Stavenga, D.G.; Barneveld, H.H. van

    1975-01-01

    An idealized visual pigment absorbance spectrum is used together with a Kramers-Kronig dispersion relation to calculate the contribution of the visual pigment to the refractive index of the fly photoreceptor. It appears that an absorption coefficient of 0.010 µm-1 results in a refractive index

  14. Dispersal in Mastomys natalensis mice

    DEFF Research Database (Denmark)

    Van Hooft, Pim; Cosson, J F; Vibe-Petersen, Solveig

    2008-01-01

    Mastomys natalensis is the major pest rodent in sub-Saharan Africa. In this study, population genetic techniques were used to gain new insights into its dispersal behaviour, a critical parameter in pest management. Using 11 microsatellites, 272 individuals from a 300 ha area in Tanzania were geno...

  15. Small area variation in diabetes prevalence in Puerto Rico.

    Science.gov (United States)

    Tierney, Edward F; Burrows, Nilka R; Barker, Lawrence E; Beckles, Gloria L; Boyle, James P; Cadwell, Betsy L; Kirtland, Karen A; Thompson, Theodore J

    2013-06-01

    To estimate the 2009 prevalence of diagnosed diabetes in Puerto Rico among adults ≥ 20 years of age in order to gain a better understanding of its geographic distribution so that policymakers can more efficiently target prevention and control programs. A Bayesian multilevel model was fitted to the combined 2008-2010 Behavioral Risk Factor Surveillance System and 2009 United States Census data to estimate diabetes prevalence for each of the 78 municipios (counties) in Puerto Rico. The mean unadjusted estimate for all counties was 14.3% (range by county, 9.9%-18.0%). The average width of the confidence intervals was 6.2%. Adjusted and unadjusted estimates differed little. These 78 county estimates are higher on average and showed less variability (i.e., had a smaller range) than the previously published estimates of the 2008 diabetes prevalence for all United States counties (mean, 9.9%; range, 3.0%-18.2%).

  16. Aspectos teóricos acerca del empresario

    Directory of Open Access Journals (Sweden)

    Javier Montes Calderón

    2015-05-01

    Full Text Available RESUMEN Complementando la línea de pensamiento de Cole podríamos decir que el empresario ha sido históricamente la figura central del desenvolvimiento económico por lo menos desde el siglo XVIII. Los elementos teóricos que a continuación se exponen constituyen un primer punto  de partida para la configuración de marcos teóricos que desde diferentes enfoques, funciones como la base fundamental para realizar el estudio del “perfil del empresario general”. Su importancia reside en el hecho de que estas categorías de análisis continúan orientando universalmente estudios sobre el empresario, que a pesar del carácter corporativo que viene asumiendo el empresario moderno, continúa siendo en buena medida el protagonista individual del desarrollo económico contemporáneo.

  17. Holismo nos modelos teóricos de enfermagem

    Directory of Open Access Journals (Sweden)

    David Lopes Neto

    1999-06-01

    Full Text Available Neste estudo bibliográfico analítico apresentamos a classificação de nove modelos teóricos de Enfermagem que abordam o pensamento holístico, segundo as escolas de pensamento das Necessidades Humanas, da Interação e dos Resultados. Com base nas definições de holismo, saúde, cliente e enfermagem analisamos a abordagem holística apresentada pelos seguintes referenciais teóricos: Teoria Ambientalista de Nightingale, Teoria Interpessoal de Peplau, Teoria Filosófica de Hall, Teoria dos Princípios Básicos de Henderson, Teoria do Autocuidado de Orem, Teoria Prescritiva de Wiedenbach, Teoria das Necessidades Humanas Básicas de Horta, Teoria da Adaptação de Roy e Teoria Holística de Levine.

  18. Usher syndrome in Puerto Rico: a clinical and genetic study.

    Science.gov (United States)

    Colón-Casasnovas, Jaime E; Izquierdo, Natalio J; Millán, Jose M

    2010-01-01

    To evaluate patients with the Usher syn drome in Puerto Rico. Three patients with the Usher syndrome underwent an ophthalmic and audiologic evaluation; and genetic linkage analysis. All patients were legally blind based on visual acuity and visual field results. Two patients had macular edema as shown on Stratus OCT. All patients had moderate hearing loss as part of the syndrome. A patient, and two family members had three mutations leading to protein changes including: p.S4588Y; p.Y4505C; and p.14474M. Phenotypic findings in patients with the Usher syndrome in Puerto Rico are similar to those previously reported. However, to our knowledge, neither these mutations nor OCT findings have been previously described in patients with the syndrome.

  19. Energy Colonialism Powers the Ongoing Unnatural Disaster in Puerto Rico

    Directory of Open Access Journals (Sweden)

    Catalina M. de Onís

    2018-01-01

    Full Text Available On September 20, 2017, Hurricane María made landfall in Puerto Rico. Blasting the Caribbean archipelago with 155-mile/h winds, this, in many ways, unnatural disaster exposed the brutal consequences of energy colonialism and an extractivist economy, as well as ongoing and increasing advocacy for decentralized solar infrastructure by many local residents and other renewables supporters. This paper argues that acknowledging colonial power relations and their consequences is essential for studying the interplay of energy systems, environments, and actors. To support this claim, this essay outlines Puerto Rico’s history as a US colony by focusing on key policies and their implications; examines openings for and barriers to decentralized, community solar in Puerto Rico; and concludes by discussing future research directions on just energy transitions and the imperative of uprooting colonialism and agitating for community self-determination and energy justice in these transformations.

  20. Small area variation in diabetes prevalence in Puerto Rico

    OpenAIRE

    Tierney, Edward F.; Burrows, Nilka R.; Barker, Lawrence E.; Beckles, Gloria L.; Boyle, James P.; Cadwell, Betsy L.; Kirtland, Karen A.; Thompson, Theodore J.

    2013-01-01

    OBJECTIVE: To estimate the 2009 prevalence of diagnosed diabetes in Puerto Rico among adults ≥ 20 years of age in order to gain a better understanding of its geographic distribution so that policymakers can more efficiently target prevention and control programs. METHODS: A Bayesian multilevel model was fitted to the combined 2008-2010 Behavioral Risk Factor Surveillance System and 2009 United States Census data to estimate diabetes prevalence for each of the 78 municipios (counties) in Puert...

  1. Ecophysiology of a Mangrove Forest in Jobos Bay, Puerto Rico

    Science.gov (United States)

    ARIEL E. LUGO; ERNESTO MEDINA; ELVIRA CUEVAs; CINTR& #211; GILBERTO N; EDDIE N. LABOY NIEVES; SCH& #196; YARA EFFER NOVELLI

    2007-01-01

    We studied gas exchange, leaf dimensions, litter production, leaf and litterfall chemistry, nutrient flux to the forest floor, retranslocation rates, and nutrient use efficiency of mangroves in Jobos Bay, Puerto Rico. The fringe forest had a salinity gradient from the ocean (35‰) to a salt flat (100‰) and a basin (about 80‰). Red (Rhizophora mangle), white (...

  2. Biblioteca integrada e sociedade referencial teórico

    OpenAIRE

    Tarapanoff, Kira

    1984-01-01

    Referencial teórico para o estudo da biblioteca como organização em relação ao seu meio ambiente imediato, específico e geral. É analisado o componente tecnológico. A biblioteca é vista como um sistema sócio-técnico-estruturado. ______________________________________________________________________________ ABSTRACT A theoretical framework is proposed to study the library as an organization in relation to its immediate, specific and general environments. The technical component is analysed....

  3. Densidad de desarrollo alta y baja en Puerto Rico

    Science.gov (United States)

    William A. Gould; Sebastian Martinuzzi; Olga M. Ramos Gonzalez

    2008-01-01

    Este mapa demuestra la distribución de terrenos de alta y baja densidad de desarrollo urbano en Puerto Rico (Martinuzzi et al. 2007). El mapa fue creado mediante el analisis de un mosaico de imagenes de satelite Landsat ETM+ de los años 2000 – 2003. La clasificacion no supervisada ISODATA (“Iterative Self-Organizing Data Analysis Technique”) (ERDAS 2003) fue utilizada...

  4. Landscape and regional impacts of hurricanes in Puerto Rico

    OpenAIRE

    Boose, Emery Robert; Serrano, Mayra I.; Foster, David Russell

    2004-01-01

    Puerto Rico is subject to frequent and severe impacts from hurricanes, whose long-term ecological role must be assessed on a scale of centuries. In this study we applied a method for reconstructing hurricane disturbance regimes developed in an earlier study of hurricanes in New England. Patterns of actual wind damage from historical records were analyzed for 85 hurricanes since European settlement in 1508. A simple meteorological model (HURRECON) was used to reconstruct the impacts of 43 hurr...

  5. Ecological consequences of petroleum spillage in the coastal waters of Puerto Rico

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, J M

    1978-01-01

    Ecological consequences of petroleum spillage in the coastal waters of Puerto Rico can be severe to corals, sea grasses, and mangroves, particularly red mangroves, according to case studies. The initial acute effect can be large, but chronic long-term effects are also possible. Oil coating of fringing stands of the red mangrove and the associated intertidal communities of their prop roots impairs productivity and destroys the attached organisms. Oil becomes trapped and may not be retrieved or cleaned from the forest. The abundance and persistence of petroleum hydrocarbons in sediments within the roots correlate with the absence of benthic organisms four years after an oil spill. Coral reefs are least impacted, and beds of the sea grass. Petroleum spills near the Puerto Rican coast include dumping of 10,000 tons of crude oil from the grounded Argea Prima on July 16, 1962., spilling the entire crude oil cargo of the Ocean Eagle on March 3, 1968 (after which dispersants did more harm than good), dumping of 37,000 bbl of crude oil by the grounded Zoe Colocotronis on March 18, 1973, spilling of 10,000 bbl of bunker C and 2000 bbl or diesel fuel from a barge on December 9, 1975, and dumping of 1000 bbl of crude from a grounded tanker in March 1977.

  6. Lessons Learned from the Puerto Rico Battery Energy Storage System

    Energy Technology Data Exchange (ETDEWEB)

    BOYES, JOHN D.; DE ANA, MINDI FARBER; TORRES, WENCESLANO

    1999-09-01

    The Puerto Rico Electric Power Authority (PREPA) installed a distributed battery energy storage system in 1994 at a substation near San Juan, Puerto Rico. It was patterned after two other large energy storage systems operated by electric utilities in California and Germany. The U.S. Department of Energy (DOE) Energy Storage Systems Program at Sandia National Laboratories has followed the progress of all stages of the project since its inception. It directly supported the critical battery room cooling system design by conducting laboratory thermal testing of a scale model of the battery under simulated operating conditions. The Puerto Rico facility is at present the largest operating battery storage system in the world and is successfully providing frequency control, voltage regulation, and spinning reserve to the Caribbean island. The system further proved its usefulness to the PREPA network in the fall of 1998 in the aftermath of Hurricane Georges. The owner-operator, PREPA, and the architect/engineer, vendors, and contractors learned many valuable lessons during all phases of project development and operation. In documenting these lessons, this report will help PREPA and other utilities in planning to build large energy storage systems.

  7. Molasses crisis in the Puerto Rico rum industry

    Energy Technology Data Exchange (ETDEWEB)

    Samuels, G

    1980-01-01

    In 1978 the Puerto Rico rum industry provided 85% of the US rum market, returning to the PR treasury $200 million in Federal excise taxes. The diminishing P.R. sugar industry is not able to supply sufficient blackstrap molasses (BSM) to the expanding P.R. rum industry, and at present imports from foreign suppliers amount to 88% of its needs. These imports place the rum industry in jeopardy, as these suppliers can boycott Puerto Rico to protect their own rum production, or they can insist by treaty that all rums claiming geographic origin (i.e., Puerto Rico rum) must be distilled from molasses produced in that country. Possible solutions to improve domestic molasses production are presented to eliminate these threats. The use of high-test molasses (HTM) would answer the present and future needs of the rum industry if produced by the energy cane (or biomass) concept. This is a management concept stressing total growth potential rather than sugar. It would permit doubling cane production per acre and produce sufficient HTM on 70,000 acres for the projected rum industry requirements. Considerations of HTM production show that problems exist with the marketing price rather than in the field or factory. The economics of HTM pricing will have to be worked out by the interested parties: the rum industry, the sugar industry, and the government.

  8. Women's employment and changing gender relations in Puerto Rico.

    Science.gov (United States)

    Warren, Alice Colón

    2010-01-01

    This article discusses Helen Safa's analyses of the impact of development strategies and social policies on gender relations and women headed families in the Caribbean and Puerto Rico. The discussion focuses on findings of a research project regarding patterns of women's employment, autonomy, marital relations, family headship and poverty in Puerto Rico in the decade beginning in the year 2000, using excerpts from interviews conducted with women workers displaced from a clothing and a tuna factory between 2001 and 2002 (Colón et al. 2008), as well as data from the Public Use Sample (PUMS) of the U.S. Census Puerto Rico Community Survey 2005-2007. It is argued that women's employment has resulted in advances in women's autonomy, gender equity, and renegotiations of the provider role, but, intensified by men's unstable earnings, it has also led to the increase of female family headship even among married women. Women's education and employment have been an important means of reducing family poverty both among dual earner families and female heads. Yet, the continuing joblessness in the Island places even higher educated sectors on the verge of economic precariousness.

  9. Community Engagement for Identifying Cancer Education Needs in Puerto Rico.

    Science.gov (United States)

    Jiménez, Julio; Ramos, Axel; Ramos-Rivera, Francisco E; Gwede, Clement; Quinn, Gwendolyn P; Vadaparampil, Susan; Brandon, Thomas; Simmons, Vani; Castro, Eida

    2018-02-01

    Cancer is the leading cause of death in Puerto Rico, suggesting a need for improved strategies, programs, and resources devoted to cancer prevention. Enhanced prevention needs in Puerto Rico were initially identified in pilot studies conducted by the Ponce School of Medicine (PSM) in collaboration with the H. Lee Moffitt Cancer Center (MCC). In the current study, we used community engagement to identify specific needs in cancer prevention and education and strategies to create culturally attuned, effective cancer prevention education programs. A total of 37 participants attended a community forum and were assigned to one of three discussion groups: patients/survivors (n = 14); family/caregivers (n = 11); or healthcare providers (n = 12). Most participants were women (73 %), over 35 years of age, and a majority were married (58 %) and had a university education (81 %). The sessions were recorded and transcribed and analyzed for key themes. Participants wanted improved awareness of cancer prevention in Puerto Rico and believed cancer prevention education should start early, ideally in elementary school. Participants also stressed the importance of creating partnerships with private and government agencies to coordinate educational efforts. Suggested strategies included outreach to communities with limited resources, incorporating the testimony of cancer survivors, and utilizing social media to disseminate cancer prevention information.

  10. 78 FR 16465 - Foreign-Trade Zone 7-Mayaguez, Puerto Rico, Authorization of Production Activity, Pepsi Cola...

    Science.gov (United States)

    2013-03-15

    ... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [B-84-2012] Foreign-Trade Zone 7--Mayaguez, Puerto Rico, Authorization of Production Activity, Pepsi Cola Puerto Rico Distributing, LLC (Soft Drink...-Trade Zones (FTZ) Board on behalf of Pepsi Cola Puerto Rico Distributing, LLC, in Toa Baja, Puerto Rico...

  11. 77 FR 43063 - Affirmation of Vertical Datum for Surveying and Mapping Activities for the Territory of Puerto Rico

    Science.gov (United States)

    2012-07-23

    ... Datum for Surveying and Mapping Activities for the Territory of Puerto Rico AGENCY: National Geodetic...-16 ( http://www.whitehouse.gov/omb/circulars/a016/a016.html ), to affirm the Puerto Rico Vertical... the islands of Puerto Rico, Culebra, Mona and Vieques of the Commonwealth of Puerto Rico and to the...

  12. Dispersion modeling by kinematic simulation: Cloud dispersion model

    International Nuclear Information System (INIS)

    Fung, J C H; Perkins, R J

    2008-01-01

    A new technique has been developed to compute mean and fluctuating concentrations in complex turbulent flows (tidal current near a coast and deep ocean). An initial distribution of material is discretized into any small clouds which are advected by a combination of the mean flow and large scale turbulence. The turbulence can be simulated either by kinematic simulation (KS) or direct numerical simulation. The clouds also diffuse relative to their centroids; the statistics for this are obtained from a separate calculation of the growth of individual clouds in small scale turbulence, generated by KS. The ensemble of discrete clouds is periodically re-discretized, to limit the size of the small clouds and prevent overlapping. The model is illustrated with simulations of dispersion in uniform flow, and the results are compared with analytic, steady state solutions. The aim of this study is to understand how pollutants disperses in a turbulent flow through a numerical simulation of fluid particle motion in a random flow field generated by Fourier modes. Although this homogeneous turbulent is rather a 'simple' flow, it represents a building block toward understanding pollutant dispersion in more complex flow. The results presented here are preliminary in nature, but we expect that similar qualitative results should be observed in a genuine turbulent flow.

  13. UV curable aqueous dispersions for wood coatings

    International Nuclear Information System (INIS)

    Peeters, S.; Bleus, J.P.; Wang, Z.J.; Arceneaux, J. A.; Hall, J.

    1999-01-01

    In this paper the characterisation of aqueous dispersions of UV curable resins is described. Two types of dispersions were used: dispersions that are tacky after water evaporation and tack - free before cure dispersions. The physical and rheological properties of these products have been determined and the performance of these dispersions in various formulations, especially for wood applications has been studied. With these dispersions, it is possible to produce coatings having a good cure speed, good surface hardness and good solvent -, chemical - and water resistance

  14. Laser control of natural disperse systems

    Science.gov (United States)

    Vlasova, Olga L.; Bezrukova, Alexandra G.

    2003-10-01

    Different water disperse systems were studied by integral (spectroturbidemetry) and differential light scattering method with a laser as a source of light. The investigation done concerns the state of kaolin dispersions at storage and under dilution as an example of mineral dispersion systems such as natural water. The role of some light scattering parameters for an optical analysis of water dispersions, like the dispersion of erythrocytes and bacterial cells -Escherichia coli is discussed. The results obtained can help to elaborate the methods for on-line optical control fo natural disperse systems (water, air) with mineral and biological particles.

  15. Nanocomposites from Stable Dispersions of Carbon Nanotubes in Polymeric Matrices Using Dispersion Interaction

    Science.gov (United States)

    Wise, Kristopher Eric (Inventor); Park, Cheol (Inventor); Kang, Jin Ho (Inventor); Siochi, Emilie J. (Inventor); Harrison, Joycelyn S. (Inventor)

    2016-01-01

    Stable dispersions of carbon nanotubes (CNTs) in polymeric matrices include CNTs dispersed in a host polymer or copolymer whose monomers have delocalized electron orbitals, so that a dispersion interaction results between the host polymer or copolymer and the CNTs dispersed therein. Nanocomposite products, which are presented in bulk, or when fabricated as a film, fiber, foam, coating, adhesive, paste, or molding, are prepared by standard means from the present stable dispersions of CNTs in polymeric matrices, employing dispersion interactions, as presented hereinabove.

  16. Elementos teóricos para el análisis empírico de la demanda

    Directory of Open Access Journals (Sweden)

    Gustavo López,

    2001-07-01

    Full Text Available El presente artículo constituye una síntesis de la teoría de la demanda y su única pretensión es la de establecer el nexo –poco usual entre nosotros- entre esa teoría y sus aplicaciones, para lo cual es necesario destacar algunos aspectos particulares. Después de un breve repaso a los elementos teóricos básicos se detallan algunas características que debe cumplir una función de demanda para que resulte adecuada a los requerimientos teóricos, así como algunas restricciones resultantes de la propia ecuación presupuestal y que impone límites a los valores de las elasticidades. Por último, se presentan algunos aspectos de la dualidad en la teoría de la demanda que son especialmente útiles en el manejo empírico.

  17. Transverse dispersion in heterogeneous fractures

    International Nuclear Information System (INIS)

    Dershowitz, Bill; Shuttle, Dawn; Klise, Kate; Outters, Nils; Hermanson, Jan

    2004-12-01

    This report evaluates the significance of transverse dispersion processes for solute transport in a single fracture. Transverse dispersion is a potentially significant process because it increases the fracture surface area available for sorptive and diffusive properties, and has the potential to transport solute between what would otherwise be distinctive, streamline pathways. Transverse dispersion processes are generally ignored in one-dimensional repository performance assessment approaches. This report provides an initial assessment of the magnitude of transverse dispersion effect in a single heterogeneous fracture on repository safety assessment. This study builds on a previous report which considered the network effects on transport dispersion including streamline routing and mixing at fracture intersections. The project uses FracMan software. This platform has been extensively used by SKB in other projects. FracMan software is designed to generate and analyze DFN's as well as to compute fluid flow in DFN's with the MAFIC Finite element method (FEM) code. Solute transport was modeled using the particle tracking inside MAFIC, the 2-D Laplace Transform Galerkin inside PAWorks/LTG, and the 1-D Laplace Transform approach designed to replicate FARF31 inside GoldSim.The study reported here focuses on a single, 20-meter scale discrete fracture, with simplified boundary conditions intended to represent the position of this fracture within a fracture network. The range of assumptions made regarding fracture heterogeneity were as follows: Base case, Heterogeneous fracture, geostatistical field, correlation length 0.01 m. Case 1a, Homogeneous fracture, transmissivity = 10 -7 m 2 /s. Case 1b, Heterogeneous fracture, non-channeled geostatistical field correlation length 5 m. Case 1c, Heterogeneous fracture, channeled, anisotropic geostatistical field. Case 1d, Heterogeneous fracture, fracture intersection zone (FIZ) permeability enhanced. Case 5, Simple channelized

  18. Procedure for preparation of dispersions

    International Nuclear Information System (INIS)

    1978-01-01

    Procedure for the preparation of a water based dispersion of cerium oxide, characterised in that a suspension of cerium (IV) hydroxide is formed with an acid, where the acid is in the state of a disaggregation of aggregated crystalline cerium hydroxide, the suspension being preheated for a specified time and to a specified temperature, so that the pH value becomes constant, and whereby the quantity of acid in the suspension is such that the constant pH value is lower than 5.4, so that a conditioned suspension may be obtained, and water may be mixed with the conditioned suspension for making a water based dispersion of cerium oxide. (G.C.)

  19. Stochastic models for atmospheric dispersion

    DEFF Research Database (Denmark)

    Ditlevsen, Ove Dalager

    2003-01-01

    Simple stochastic differential equation models have been applied by several researchers to describe the dispersion of tracer particles in the planetary atmospheric boundary layer and to form the basis for computer simulations of particle paths. To obtain the drift coefficient, empirical vertical...... positions close to the boundaries. Different rules have been suggested in the literature with justifications based on simulation studies. Herein the relevant stochastic differential equation model is formulated in a particular way. The formulation is based on the marginal transformation of the position...... velocity distributions that depend on height above the ground both with respect to standard deviation and skewness are substituted into the stationary Fokker/Planck equation. The particle position distribution is taken to be uniform *the well/mixed condition( and also a given dispersion coefficient...

  20. Ability Dispersion and Team Performance

    DEFF Research Database (Denmark)

    Hoogendoorn, Sander; Parker, Simon C.; Van Praag, Mirjam

    What is the effect of dispersed levels of cognitive ability of members of a (business) team on their team's performance? This paper reports the results of a field experiment in which 573 students in 49 (student) teams start up and manage real companies under identical circumstances for one year. We...... ensured exogenous variation in otherwise random team composition by assigning students to teams based on their measured cognitive abilities. Each team performs a variety of tasks, often involving complex decision making. The key result of the experiment is that the performance of business teams first...... increases and then decreases with ability dispersion. We seek to understand this finding by developing a model in which team members of different ability levels form sub- teams with other team members with similar ability levels to specialize in different productive tasks. Diversity spreads production over...

  1. Magnetic effects in anomalous dispersion

    International Nuclear Information System (INIS)

    Blume, M.

    1992-01-01

    Spectacular enhancements of magnetic x-ray scattering have been predicted and observed experimentally. These effects are the result of resonant phenomena closely related to anomalous dispersion, and they are strongest at near-edge resonances. The theory of these resonances will be developed with particular attention to the symmetry properties of the scatterer. While the phenomena to be discussed concern magnetic properties the transitions are electric dipole or electric quadrupole in character and represent a subset of the usual anomalous dispersion phenomena. The polarization dependence of the scattering is also considered, and the polarization dependence for magnetic effects is related to that for charge scattering and to Templeton type anisotropic polarization phenomena. It has been found that the strongest effects occur in rare-earths and in actinides for M shell edges. In addition to the scattering properties the theory is applicable to ''forward scattering'' properties such as the Faraday effect and circular dichroism

  2. Faraday anomalous dispersion optical tuners

    Science.gov (United States)

    Wanninger, P.; Valdez, E. C.; Shay, T. M.

    1992-01-01

    Common methods for frequency stabilizing diode lasers systems employ gratings, etalons, optical electric double feedback, atomic resonance, and a Faraday cell with low magnetic field. Our method, the Faraday Anomalous Dispersion Optical Transmitter (FADOT) laser locking, is much simpler than other schemes. The FADOT uses commercial laser diodes with no antireflection coatings, an atomic Faraday cell with a single polarizer, and an output coupler to form a compound cavity. This method is vibration insensitive, thermal expansion effects are minimal, and the system has a frequency pull in range of 443.2 GHz (9A). Our technique is based on the Faraday anomalous dispersion optical filter. This method has potential applications in optical communication, remote sensing, and pumping laser excited optical filters. We present the first theoretical model for the FADOT and compare the calculations to our experimental results.

  3. Dispersed Fringe Sensing Analysis - DFSA

    Science.gov (United States)

    Sigrist, Norbert; Shi, Fang; Redding, David C.; Basinger, Scott A.; Ohara, Catherine M.; Seo, Byoung-Joon; Bikkannavar, Siddarayappa A.; Spechler, Joshua A.

    2012-01-01

    Dispersed Fringe Sensing (DFS) is a technique for measuring and phasing segmented telescope mirrors using a dispersed broadband light image. DFS is capable of breaking the monochromatic light ambiguity, measuring absolute piston errors between segments of large segmented primary mirrors to tens of nanometers accuracy over a range of 100 micrometers or more. The DFSA software tool analyzes DFS images to extract DFS encoded segment piston errors, which can be used to measure piston distances between primary mirror segments of ground and space telescopes. This information is necessary to control mirror segments to establish a smooth, continuous primary figure needed to achieve high optical quality. The DFSA tool is versatile, allowing precise piston measurements from a variety of different optical configurations. DFSA technology may be used for measuring wavefront pistons from sub-apertures defined by adjacent segments (such as Keck Telescope), or from separated sub-apertures used for testing large optical systems (such as sub-aperture wavefront testing for large primary mirrors using auto-collimating flats). An experimental demonstration of the coarse-phasing technology with verification of DFSA was performed at the Keck Telescope. DFSA includes image processing, wavelength and source spectral calibration, fringe extraction line determination, dispersed fringe analysis, and wavefront piston sign determination. The code is robust against internal optical system aberrations and against spectral variations of the source. In addition to the DFSA tool, the software package contains a simple but sophisticated MATLAB model to generate dispersed fringe images of optical system configurations in order to quickly estimate the coarse phasing performance given the optical and operational design requirements. Combining MATLAB (a high-level language and interactive environment developed by MathWorks), MACOS (JPL s software package for Modeling and Analysis for Controlled Optical

  4. Hydrodynamic dispersion within porous biofilms

    KAUST Repository

    Davit, Y.

    2013-01-23

    Many microorganisms live within surface-associated consortia, termed biofilms, that can form intricate porous structures interspersed with a network of fluid channels. In such systems, transport phenomena, including flow and advection, regulate various aspects of cell behavior by controlling nutrient supply, evacuation of waste products, and permeation of antimicrobial agents. This study presents multiscale analysis of solute transport in these porous biofilms. We start our analysis with a channel-scale description of mass transport and use the method of volume averaging to derive a set of homogenized equations at the biofilm-scale in the case where the width of the channels is significantly smaller than the thickness of the biofilm. We show that solute transport may be described via two coupled partial differential equations or telegrapher\\'s equations for the averaged concentrations. These models are particularly relevant for chemicals, such as some antimicrobial agents, that penetrate cell clusters very slowly. In most cases, especially for nutrients, solute penetration is faster, and transport can be described via an advection-dispersion equation. In this simpler case, the effective diffusion is characterized by a second-order tensor whose components depend on (1) the topology of the channels\\' network; (2) the solute\\'s diffusion coefficients in the fluid and the cell clusters; (3) hydrodynamic dispersion effects; and (4) an additional dispersion term intrinsic to the two-phase configuration. Although solute transport in biofilms is commonly thought to be diffusion dominated, this analysis shows that hydrodynamic dispersion effects may significantly contribute to transport. © 2013 American Physical Society.

  5. Dispersion of Bed Load Particles

    OpenAIRE

    SAWAI, Kenji

    1987-01-01

    The motion of bed load particles is so irregular that they disperse remarkably with time.In this study, some flume tests using painted tracer particles were carried out, in which thedispersive property of tracers changed variously with sediment feed rate.In analysing this process, a stochastic simulation model is proposed where it is discussedabout the degree of exposure of individual particle near the bed surface and about the variationof its pick up rate. The exponential distribution of ste...

  6. Faraday anomalous dispersion optical filters

    Science.gov (United States)

    Shay, T. M.; Yin, B.; Alvarez, L. S.

    1993-01-01

    The effect of Faraday anomalous dispersion optical filters on infrared and blue transitions of some alkali atoms is calculated. A composite system is designed to further increase the background noise rejection. The measured results of the solar background rejection and image quality through the filter are presented. The results show that the filter may provide high transmission and high background noise rejection with excellent image quality.

  7. Dispersive stresses in wind farms

    Science.gov (United States)

    Segalini, Antonio; Braunbehrens, Robert; Hyvarinen, Ann

    2017-11-01

    One of the most famous models of wind farms is provided by the assumption that the farm can be approximated as a horizontally-homogeneous forest canopy with vertically-varying force intensity. By means of this approximation, the flow-motion equations become drastically simpler, as many of the three-dimensional effects are gone. However, the application of the horizontal average operator to the RANS equations leads to the appearance of new transport terms (called dispersive stresses) originating from the horizontal (small-scale) variation of the mean velocity field. Since these terms are related to the individual turbine signature, they are expected to vanish outside the roughness sublayer, providing a definition for the latter. In the present work, an assessment of the dispersive stresses is performed by means of a wake-model approach and through the linearised code ORFEUS developed at KTH. Both approaches are very fast and enable the characterization of a large number of wind-farm layouts. The dispersive stress tensor and its effect on the turbulence closure models are investigated, providing guidelines for those simulations where it is impossible to resolve the farm at a turbine scale due to grid requirements (as, for instance, mesoscale simulations).

  8. Improving practical atmospheric dispersion models

    International Nuclear Information System (INIS)

    Hunt, J.C.R.; Hudson, B.; Thomson, D.J.

    1992-01-01

    The new generation of practical atmospheric dispersion model (for short range ≤ 30 km) are based on dispersion science and boundary layer meteorology which have widespread international acceptance. In addition, recent improvements in computer skills and the widespread availability of small powerful computers make it possible to have new regulatory models which are more complex than the previous generation which were based on charts and simple formulae. This paper describes the basis of these models and how they have developed. Such models are needed to satisfy the urgent public demand for sound, justifiable and consistent environmental decisions. For example, it is preferable that the same models are used to simulate dispersion in different industries; in many countries at present different models are used for emissions from nuclear and fossil fuel power stations. The models should not be so simple as to be suspect but neither should they be too complex for widespread use; for example, at public inquiries in Germany, where simple models are mandatory, it is becoming usual to cite the results from highly complex computational models because the simple models are not credible. This paper is written in a schematic style with an emphasis on tables and diagrams. (au) (22 refs.)

  9. Dispersion relations in loop calculations

    International Nuclear Information System (INIS)

    Kniehl, B.A.

    1996-01-01

    These lecture notes give a pedagogical introduction to the use of dispersion relations in loop calculations. We first derive dispersion relations which allow us to recover the real part of a physical amplitude from the knowledge of its absorptive part along the branch cut. In perturbative calculations, the latter may be constructed by means of Cutkosky's rule, which is briefly discussed. For illustration, we apply this procedure at one loop to the photon vacuum-polarization function induced by leptons as well as to the γf anti-f vertex form factor generated by the exchange of a massive vector boson between the two fermion legs. We also show how the hadronic contribution to the photon vacuum polarization may be extracted from the total cross section of hadron production in e + e - annihilation measured as a function of energy. Finally, we outline the application of dispersive techniques at the two-loop level, considering as an example the bosonic decay width of a high-mass Higgs boson. (author)

  10. Chromatic Dispersion Estimation in Digital Coherent Receivers

    DEFF Research Database (Denmark)

    Soriano, Ruben Andres; Hauske, Fabian N.; Guerrero Gonzalez, Neil

    2011-01-01

    Polarization-diverse coherent demodulation allows to compensate large values of accumulated linear distortion by digital signal processing. In particular, in uncompensated links without optical dispersion compensation, the parameter of the residual chromatic dispersion (CD) is vital to set...

  11. Statistical Physics of Colloidal Dispersions.

    Science.gov (United States)

    Canessa, E.

    Available from UMI in association with The British Library. Requires signed TDF. This thesis is concerned with the equilibrium statistical mechanics of colloidal dispersions which represent useful model systems for the study of condensed matter physics; namely, charge stabilized colloidal dispersions and polymer stabilized colloidal dispersions. A one-component macroparticle approach is adopted in order to treat the macroscopic and microscopic properties of these systems in a simple and comprehensive manner. The thesis opens with the description of the nature of the colloidal state before reviewing some basic definitions and theory in Chapter II. In Chapter III a variational theory of phase equilibria based on the Gibbs-Bogolyobov inequality is applied to sterically stabilized colloidal dispersions. Hard spheres are chosen as the reference system for the disordered phases while an Einstein model is used for the ordered phases. The new choice of pair potential, taken for mathematical convenience, is a superposition of two Yukawa functions. By matching a double Yukawa potential to the van der Waals attractive potential at different temperatures and introducing a purely temperature dependent coefficient to the repulsive part, a rich variety of observed phase separation phenomena is qualitatively described. The behaviour of the potential is found to be consistent with a small decrease of the polymer layer thickness with increasing temperature. Using the same concept of a collapse transition the non-monotonic second virial coefficient is also explained and quantified. It is shown that a reduction of the effective macroparticle diameter with increasing temperature can only be partially examined from the point of view of a (binary-) polymer solution theory. This chapter concludes with the description of the observed, reversible, depletion flocculation behaviour. This is accomplished by using the variational formalism and by invoking the double Yukawa potential to allow

  12. Dispersion properties of photonic crystal fibres

    DEFF Research Database (Denmark)

    Bjarklev, Anders Overgaard; Broeng, Jes; Dridi, Kim

    1998-01-01

    Approximate dispersion and bending properties of all-silica two-dimensional photonic crystal fibres are characterised by the combination of an effective-index model and classical analysis tools for optical fibres. We believe for the first time to have predicted the dispersion properties of photonic...... crystal fibres. The results strongly indicate that these fibres have potential applications as dispersion managing components...

  13. Catchment Dispersion Mechanisms in an Urban Context

    Science.gov (United States)

    Gironas, J. A.; Mejia, A.; Rossel, F.; Rinaldo, A.; Rodriguez, F.

    2014-12-01

    Dispersion mechanisms have been examined in-depth in natural catchments in previous studies. However, these dispersion mechanisms have been studied little in urban catchments, where artificial transport elements and morphological arrangements are expected to modify travel times and mobilize excess rainfall from spatially distributed impervious sites. Thus, these features can modify the variance of the catchment's travel times and hence the total dispersion. This work quantifies the dispersion mechanisms in an urban catchment using the theory of transport by travel times as represented by the Urban Morpho-climatic Instantaneous Unit Hydrograph (U-McIUH) model. This model computes travel times based on kinematic wave theory and accounts explicitly for the path heterogeneities and altered connectivity patterns characteristic of an urban drainage network. The analysis is illustrated using the Aubinière urban catchment (France) as a case study. We found that kinematic dispersion is dominant for small rainfall intensities, whereas geomorphologic dispersion becomes more dominant for larger intensities. The total dispersion scales with the drainage area in a power law fashion. The kinematic dispersion is dominant across spatial scales up to a threshold of approximately 2-3 km2, after which the geomorphologic dispersion becomes more dominant. Overall, overland flow is responsible for most of the dispersion, while conduits tend to counteract the increase of the geomorphologic dispersion with a negative kinematic dispersion. Further studies with other catchments are needed to assess whether the latter is a general feature of urban drainage networks.

  14. Dispersion of coupled mode-gap cavities

    NARCIS (Netherlands)

    Lian, Jin; Sokolov, Sergei; Yuce, E.; Combrie, S.; de Rossi, A.; Mosk, Allard

    2015-01-01

    The dispersion of a coupled resonator optical waveguide made of photonic crystal mode-gap cavities is pronouncedly asymmetric. This asymmetry cannot be explained by the standard tight binding model. We show that the fundamental cause of the asymmetric dispersion is the inherent dispersive cavity

  15. Characterization of finite spaces having dispersion points

    International Nuclear Information System (INIS)

    Al-Bsoul, A. T

    1997-01-01

    In this paper we shall characterize the finite spaces having dispersion points. Also, we prove that the dispersion point of a finite space with a dispersion points fixed under all non constant continuous functions which answers the question raised by J. C obb and W. Voxman in 1980 affirmatively for finite space. Some open problems are given. (author). 16 refs

  16. Psychosocial risk factors and asthma among adults in Puerto Rico.

    Science.gov (United States)

    Han, Yueh-Ying; Forno, Erick; Canino, Glorisa; Celedón, Juan C

    2018-05-08

    Asthma and psychosocial stressors are common among Puerto Rican adults living in the United States. We estimated the prevalence of current asthma, and examined potential psychosocial risk factors and current asthma, among adults in Puerto Rico. Cross-sectional study of 3,049 Puerto Ricans aged 18-64 years living in Puerto Rico between May 2014 and June 2016. A structured interview was conducted to obtain information on demographics, lifestyles, mental disorders, and respiratory health. Current asthma was defined as self-reported physician-diagnosed asthma and still having asthma. Two-sample t tests (for continuous variables) or chi-square tests (for categorical variables) were used in bivariate analyses. Multivariable logistic regression was used to examine psychosocial risk factors and current asthma. The estimated prevalence of current asthma was 10.2%. In a multivariable analysis, exposure to violence (odds ratio [OR] for each 1-point increment in a validated scale = 1.14, 95% confidence interval [CI] = 1.07 to 1.21) and a lifetime history of at least one suicide attempt (OR = 3.01, 95% CI = 1.80 to 5.01) were significantly associated with current asthma, independently of major depressive disorder. Moreover, a lifetime history of at least one suicide attempt was associated with co-existing asthma and chronic obstructive pulmonary disease (i.e. asthma-COPD overlap syndrome or ACOS (OR = 9.05, 95% CI = 3.32-24.67). Our findings suggest that asthma is a major health problem among adults in Puerto Rico, with psychosocial risk factors playing a significant role on asthma and ACOS. Addressing chronic stressors and mental illness should be part of comprehensive strategies to reduce asthma burden in this population.

  17. Sedimentation Survey of Lago La Plata, Puerto Rico, July 2006

    Science.gov (United States)

    Soler-López, Luis R.

    2008-01-01

    Lago La Plata dam is located between the municipalities of Naranjito and Toa Alta in north central Puerto Rico, about 5 kilometers south of the town of Toa Alta and about 5 kilometers north of the town of Naranjito. The reservoir impounds the waters of the Rio de La Plata, the Rio Guadiana, and the Rio Ca?as, and is part of the San Juan Metropolitan Water District, which provides about 35 percent of the total water demand for the area (Soler-Lopez and others, 2000). The reservoir has a drainage area of about 469 square kilometers. The dam was constructed in 1974 and is a concrete gravity structure with a normal pool elevation of 52.00 meters above mean sea level (Puerto Rico Electric Power Authority, 1979). During October 1998, the U.S. Geological Survey (USGS), Caribbean Water Science Center, in cooperation with the Puerto Rico Aqueduct and Sewer Authority (PRASA) conducted a bathymetric survey of Lago La Plata to assess the impact of Hurricane Georges on the storage capacity of the reservoir. Between July 17 and 20, 2006, the USGS and the PRASA conducted an additional bathymetric survey of Lago La Plata to update the reservoir storage capacity and determine the reservoir sedimentation rate by comparing the 2006 survey data with the 1998 survey data.. The purpose of this report is to update the reservoir storage capacity, sedimentation rates, and areas of substantial sediment accumulation since 1998. Historical (1974) data are referenced as needed to account for long-term storage capacity loss trends...

  18. Photonics outreach and education through partnerships in Puerto Rico

    Science.gov (United States)

    Friedman, Jonathan S.; Diaz, Andres; Saltares, Roger; Luciano, Sarah; Molina, Nerivette; Martinez, Smailyn; Hernandez, Alejandro; de Jesus, Johan; Rivera, Yesenia; Capeles, Antonio; Alvear, Felipe; Lopez, Jesus; Rivera, Miguel; Saurez, Rey; Trujillo, Elsa

    2015-10-01

    As the only photonics center in Puerto Rico, the Puerto Rico Photonics Institute (PRPI) has developed education and outreach projects, partnering with other institutions and private companies to optimize the use of available resources. We present our experience, challenges, rewards, and results for the following projects: - Tours: K-12 students visit our facilities in a science tour including a presentation on the Arecibo Observatory (AO) and the Digital Planet Geodome. We present optics demonstrations and other information. In the first three months we hosted fifteen schools impacting over 1,400 students. - Outreach: We have newly active outreach and recruiting activities for Puerto Rico (PR) schools. - Teachers: With the PR Math-Science Partnership (MSP) Program, we have given a full-day workshop on optics and photonics experiments for 5th-12th grade teachers, and a master class at the annual MSP Congress. We have impacted over 500 teachers through these initiatives. - Continuing Education: We have given continuing education courses in addition to the MSP workshops. - General Public: We partner with museums in PR, the University of Turabo, and the AO Visitor Center to build optics exhibits, many developed by students. - Video: PRPI is promoting the 2015 International Year of Light, creating: 1. A short video with students and faculty from the Universidad Metropolitana (UMET) Schools of Communication and Business Administration; 2. A longer video with the production company Geoambiente. - Apps: Our website will include ray tracing and wave propagation applications, developed by UMET Computer Science students. - Capstone: Engineering students at the School of Engineering at Universidad del Turabo are developing laser pattern generators.

  19. Inteligencias en diferentes enfoques teóricos

    Directory of Open Access Journals (Sweden)

    D'Antoni, Maurizia

    2004-06-01

    Full Text Available El siguiente artículo reflexiona sobre enfoques teóricos que sustentan el estudio de las inteligencias y su pertinencia. Se toman en cuenta dos diferentes enfoques teóricos: el humanismo –tomando en cuenta una de sus recientes reformulaciones- y el cognitivismo, específicamente el aporte de Gardner. Al preguntarse el texto si los conceptos de “inteligencias personales” y “persona autorrealizada” tienen alguna relación teórica, se reseñan y comparan algunas de las principales conclusiones de Abraham Maslow y Howard Gardner. Este artículo es parte del trabajo que se realiza para trazar el marco teórico de un proyecto de extensión para la Universidad Nacional, denominado “Olimpiadas de la Inteligencia Emocional”. En ese mismo ámbito, se reflexiona sobre la orientación teórica de otros estudios latinoamericanos y su validez. The next article is a reflection upon theoretical focuses that sustain the study of intelligence and their pertinence. It explores the perspective of two different theoretical approaches, humanism –taking into account one of the recent reformulations- and cognitivism, in the broadest sense of the term. The text queries whether the concepts of “personal intelligences” and “self realized person” have any theoretical relation, it resumes them and compares some of the principal contributions made by Abraham Maslow and Howard Gardner. This article is part of the work that was undertaken to establish the theoretical guidelines of an extension project by the Universidad Nacional, titled “Emotional Intelligence Olympics”. In the same context, there is a reflection on the theoretical orientation of other latinamerican studies and their validity.

  20. La ciencia del tabaco en Puerto Rico, 1900-1940

    Directory of Open Access Journals (Sweden)

    Levy, Teresita

    2015-06-01

    Full Text Available Tobacco became an important export product in Puerto Rico after the American occupation of 1898, in large part, because of investments in the scientific study of tobacco: its efficient cultivation, its economic structure and its marketing. Scientific experimentation and the practical application of research findings in tobacco farms provided an arena for significant collaborative relationships between tobacco growers, scientists in Puerto Rico and the U.S., and the insular and federal governments. The involvement of Puerto Ricans in the science of tobacco, including their support of scientific inquiry, their continued demands for funding and beneficial agricultural legislation, and their adoption of modern agricultural technology, demonstrate that rather than being observers of rapid economic changes, they were activists, using the democratic guarantees available under the U.S. colonial structure to improve their economic situation.El tabaco se convirtió en un importante producto de exportación para Puerto Rico después de la ocupación norteamericana de 1898, debido a las inversiones en su estudio científico: el cultivo eficiente, la estructura económica y el mercadeo. La experimentación científica y la aplicación práctica de los descubrimientos en las fincas tabacaleras ofrecieron un campo de saber para establecer relaciones cooperativas significativas entre los cultivadores, los científicos en Puerto Rico y EEUU, y el gobierno insular y federal. El compromiso de los puertorriqueños en la ciencia del tabaco, incluyendo su apoyo por la investigación, las demandas continuas para fondos y una legislación agrícola beneficiosa, así como la adopción de la tecnología agrícola moderna, demuestra que éstos no eran pasivos frente a los rápidos cambios económicos de entonces. Por el contrario, ellos eran activistas políticos, usando las garantías democráticas disponibles dentro de la estructura colonial de los EEUU para mejorar su

  1. Sistema genérico de replicación

    OpenAIRE

    Jiménez Ortiz, Raúl

    2014-01-01

    Este proyecto se desarrolla en una de las principales compañías eléctricas de España, y trata sobre la creación de un sistema genérico de replicación de datos. La idea surge de la necesidad de estandarizar la forma de traspasar información entre departamentos o sistemas, debido a que existen gran variedad de interfaces diferentes, y cada vez que surge la necesidad de crear una implica nuevos costes de desarrollo, mantenimiento y futuros evolutivos. Entre los diferentes departamentos de ...

  2. Political power and health inequalities in Vieques, Puerto Rico.

    Science.gov (United States)

    Medina, Catherine K; Pellegrini, Lawrence C; Mogro-Wilson, Cristina

    2014-01-01

    The relationship between political power and the various pathways to health inequalities in Vieques, Puerto Rico, is explored. The U.S. Navy used the island for 62 years for bombing and other military exercises. The article focuses on the resulting changes to the island's socioeconomic positioning and the health inequalities over six decades. Secondary data analysis of census data using a revised World Health Organization model is used to examine the relationships of political power, labor markets, employment, material deprivation, social and family networks, and health inequalities. Findings are interpreted through a social justice lens and implications suggest the use of political advocacy for social change.

  3. Puerto Rico [Marine Radioecology. Current Research and Future Scope

    International Nuclear Information System (INIS)

    Lowman, Frank G.

    1967-01-01

    Present research programme: Marine biology programme (marine biogeochemistry). The programme is designed to provide measurements of the distribution and movements of selected trace elements in a restricted but complete ecological and biogeochemical system. To obtain information on interactions between the marine biosphere and hydrosphere, measurements are being made of biological productivity, amounts of trace elements in the organisms and the environment, biological half-lives of trace elements, characteristics of food webs, and the influence of physical and chemical oceanographic factors upon the distribution patterns of trace elements in the marine waters, organisms and sediments offshore from the west coast of Puerto Rico

  4. Normal-dispersion microresonator Kerr frequency combs

    Directory of Open Access Journals (Sweden)

    Xue Xiaoxiao

    2016-06-01

    Full Text Available Optical microresonator-based Kerr frequency comb generation has developed into a hot research area in the past decade. Microresonator combs are promising for portable applications due to their potential for chip-level integration and low power consumption. According to the group velocity dispersion of the microresonator employed, research in this field may be classified into two categories: the anomalous dispersion regime and the normal dispersion regime. In this paper, we discuss the physics of Kerr comb generation in the normal dispersion regime and review recent experimental advances. The potential advantages and future directions of normal dispersion combs are also discussed.

  5. Dispersed publication of editorial research

    DEFF Research Database (Denmark)

    Rosenberg, Jacob; Pommergaard, Hans-Christian; Vinther, Siri

    2015-01-01

    INTRODUCTION: There seems to be no dedicated journals available for publication of editorial research in the biomedical sciences; that is research into editorial or publication process issues involving the scientific approach to writing, reviewing, editing and publishing. It is unknown where papers...... journals with a median of one article per journal (range: 1-17). CONCLUSION: The publication of papers on editorial research seems to be dispersed. In order to increase the visibility of this research field, it may be reasonable to establish well-defined platforms such as dedicated journals or journal...

  6. A nonlocal inhomogeneous dispersal process

    Science.gov (United States)

    Cortázar, C.; Coville, J.; Elgueta, M.; Martínez, S.

    This article in devoted to the study of the nonlocal dispersal equation u(x,t)=∫R J({x-y}/{g(y)}){u(y,t)}/{g(y)} dy-u(x,t) in R×[0,∞), and its stationary counterpart. We prove global existence for the initial value problem, and under suitable hypothesis on g and J, we prove that positive bounded stationary solutions exist. We also analyze the asymptotic behavior of the finite mass solutions as t→∞, showing that they converge locally to zero.

  7. Taylor dispersion on a fractal

    International Nuclear Information System (INIS)

    Mazo, R.M.

    1998-01-01

    Taylor dispersion is the greatly enhanced diffusion in the direction of a fluid flow caused by ordinary diffusion in directions orthogonal to the flow. It is essential that the system be bounded in space in the directions orthogonal to the flow. We investigate the situation where the medium through which the flow occurs has fractal properties so that diffusion in the orthogonal directions is anomalous and non-Fickian. The effective diffusion in the flow direction remains normal; its width grows proportionally with the time. However, the proportionality constant depends on the fractal dimension of the medium as well as its walk dimension. (author)

  8. Ejercicios de Topografía: Una aplicación de pedagogías intensivas (Desarrollos teóricos y numéricos)

    OpenAIRE

    Zapata Ocampo, Oscar de Jesus; Mejía Gutiérrez, Ángela Beatriz; Agudelo, Laura Inés

    2008-01-01

    Con este texto se pretende contribuir a llenar una de las falencias del medio en el cual existen una gran cantidad de libros desde los clásicos hasta los últimos aportes, que presentan grandes desarrollos teóricos, pero solo plantean o resuelven unos pocos ejercicios teóricos o numéricos. Este trabajo pedagógico trata de construir una herramienta de estudio autocontenida y de taller, al entregar una parte inicial con formulaciones de cuestionamiento que luego tienen un desenvolvimiento a modo...

  9. Extragalactic dispersion measures of fast radio bursts

    International Nuclear Information System (INIS)

    Xu, Jun; Han, J. L.

    2015-01-01

    Fast radio bursts show large dispersion measures, much larger than the Galactic dispersion measure foreground. Therefore, they evidently have an extragalactic origin. We investigate possible contributions to the dispersion measure from host galaxies. We simulate the spatial distribution of fast radio bursts and calculate the dispersion measures along the sightlines from fast radio bursts to the edge of host galaxies by using the scaled NE2001 model for thermal electron density distributions. We find that contributions to the dispersion measure of fast radio bursts from the host galaxy follow a skew Gaussian distribution. The peak and the width at half maximum of the dispersion measure distribution increase with the inclination angle of a spiral galaxy, to large values when the inclination angle is over 70°. The largest dispersion measure produced by an edge-on spiral galaxy can reach a few thousand pc cm −3 , while the dispersion measures from dwarf galaxies and elliptical galaxies have a maximum of only a few tens of pc cm −3 . Notice, however, that additional dispersion measures of tens to hundreds of pc cm −3 can be produced by high density clumps in host galaxies. Simulations that include dispersion measure contributions from the Large Magellanic Cloud and the Andromeda Galaxy are shown as examples to demonstrate how to extract the dispersion measure from the intergalactic medium. (paper)

  10. Small area variation in diabetes prevalence in Puerto Rico

    Directory of Open Access Journals (Sweden)

    Edward F. Tierney

    2013-06-01

    Full Text Available OBJECTIVE: To estimate the 2009 prevalence of diagnosed diabetes in Puerto Rico among adults ≥ 20 years of age in order to gain a better understanding of its geographic distribution so that policymakers can more efficiently target prevention and control programs. METHODS: A Bayesian multilevel model was fitted to the combined 2008-2010 Behavioral Risk Factor Surveillance System and 2009 United States Census data to estimate diabetes prevalence for each of the 78 municipios (counties in Puerto Rico. RESULTS: The mean unadjusted estimate for all counties was 14.3% (range by county, 9.9%-18.0%. The average width of the confidence intervals was 6.2%. Adjusted and unadjusted estimates differed little. CONCLUSIONS: These 78 county estimates are higher on average and showed less variability (i.e., had a smaller range than the previously published estimates of the 2008 diabetes prevalence for all United States counties (mean, 9.9%; range, 3.0%-18.2%.

  11. Hurricane Impact on Seepage Water in Larga Cave, Puerto Rico

    Science.gov (United States)

    Vieten, Rolf; Warken, Sophie; Winter, Amos; Schröder-Ritzrau, Andrea; Scholz, Denis; Spötl, Christoph

    2018-03-01

    Hurricane-induced rainfall over Puerto Rico has characteristic δ18O values which are more negative than local rainfall events. Thus, hurricanes may be recorded in speleothems from Larga cave, Puerto Rico, as characteristic oxygen isotope excursions. Samples of 84 local rainfall events between 2012 and 2013 ranged from -6.2 to +0.3‰, whereas nine rainfall samples belonging to a rainband of hurricane Isaac (23-24 August 2012) ranged from -11.8 to -7.1‰. Cave monitoring covered the hurricane season of 2014 and investigated the impact of hurricane rainfall on drip water chemistry. δ18O values were measured in cumulative monthly rainwater samples above the cave. Inside the cave, δ18O values of instantaneous drip water samples were analyzed and drip rates were recorded at six drip sites. Most effective recharge appears to occur during the wet months (April-May and August-November). δ18O values of instantaneous drip water samples ranged from -3.5 to -2.4‰. In April 2014 and April 2015 some drip sites showed more negative δ18O values than the effective rainfall (-2.9‰), implying an influence of hurricane rainfall reaching the cave via stratified seepage flow months to years after the event. Speleothems from these drip sites in Larga cave have a high potential for paleotempestology studies.

  12. Mercury and cadmium concentrations in milk in Puerto Rico

    International Nuclear Information System (INIS)

    Chellapan, S.; Pedersen, K.B.; Plaza, H.

    1976-01-01

    Milk was collected over a four-month period from three representative sectors of Puerto Rico. Instrumental neutron activation analysis (INAA) performed on the samples showed that the mercury concentration was slightly higher than safe upper limit set by the World Health Organization on food products. The values reported here for mercury concentrations are very similar to those found for dairy products in the Toronto area of Canada in 1970, but considerably higher than some reported from the United States in 1964. Mean cadmium concentrations were found to be higher than the values reported in the literature. Some variations in cadmium concentrations were observed areawide as well as a function of time. MURTHY et al reported the cadmium concentration in milk to be 0.018 to 0.03 ppm in the United States in the year 1967; this is about one sixth of the concentrations found in this study for Puerto Rico. In addition to INAA atomic absorption photospectrometry was used on a smaller number of samples to verify the concentration levels of cadmium. For this determination nine milk samples and two blanks were analyzed. The concentrations were found to vary between 0.01 and 0.06 ppm. These values are in better agreement with the values reported for the United States than are the ones obtained from using INAA; however, their spread is much greater. (T.G.)

  13. Physical aspects of Hurricane Hugo in Puerto Rico

    Science.gov (United States)

    Scatena, F.N.; Larsen, Matthew C.

    1991-01-01

    On 18 September 1989 the western part ofHurricane Hugo crossed eastern Puerto Rico and the Luquillo Experimental Forest (LEF). Storm-facing slopes on the northeastern part of the island that were within 15 km of the eye and received greater than 200 mm of rain were most affected by the storm. In the LEF and nearby area, recurrence intervals associated with Hurricane Hugo were 50 yr for wind velocity, 10 to 31 yr for stream discharge, and 5 yr for rainfall intensity. To compare the magnitudes of the six hurricanes to pass over PuertoRico since 1899, 3 indices were developed using the standardized values of the product of: the maximum sustained wind speed at San Juan squared and storm duration; the square of the product of the maximum sustained wind velocity at San Juan and the ratio of the distance between the hurricane eye and San Juan to the distance between the eye and percentage of average annual rainfall delivered by the storm. Based on these indices, HurricaneHugo was of moderate intensity. However, because of the path of Hurricane Hugo, only one of these six storms (the 1932 storm) caused more damage to the LEF than Hurricane Hugo. Hurricanes of Hugo's magnitude are estimated to pass over the LEF once every 50-60 yr, on average. 

  14. Américo Castro en Houston: 1955-59

    Directory of Open Access Journals (Sweden)

    Nancy F. MARINO

    2009-11-01

    Full Text Available A partir del año 1936 la vida del filólogo y profesor Américo Castro le lleva a tierras americanas, donde permanece como catedrático en varias universidades mientras escribe la mayoría de sus obras maestras. En 1936 es profesor en Buenos Aires, pero un año más tarde reanuda la carrera docente en Estados Unidos, primero en la Universidad de Wisconsin (1937-39, después en la de Tejas (1939-40, y por fin en Princeton donde se pasa más de veinte años. Su jubilación a los 68 años de edad se debe a la inflexibilidad del sistema que le obliga a retirarse, y no a su deseo de dejar de dar clases. Después de abandonar su cátedra en Princeton —aunque siempre mantendrá su hogar en esa ciudad a pesar de sus varias andanzas— D. Américo se va a Venezuela para dar una serie de conferencias y para seguir trabajando en sus obras.

  15. Control of schistosomiasis in Guayama and Arroyo, Puerto Rico*

    Science.gov (United States)

    Jobin, William R.; Ferguson, Frederick F.; Palmer, Juan R.

    1970-01-01

    In 1953, a programme to control schistosomiasis mansoni was started in Guayama and Arroyo, Puerto Rico, employing, first, chemical and, later, both biological and chemical methods to control Biomphalaria glabrata, the snail host of Schistosoma mansoni. Sodium pentachlorophenate was the molluscicide, and an ampullarid snail, Marisa cornuarietis, was used for biological control in ponds and reservoirs. In addition some chemotherapy was given to infected persons. The prevalence of intestinal schistosomiasis was measured annually, sampling about one-third of the 6-year-old population in Guayama and Arroyo and in Caguas, an untreated area. Costs of the programme and the results are discussed in relation to similar projects in other parts of Puerto Rico. In Guayama and Arroyo the prevalence of schistosomiasis reached zero in 6-year-olds by 1966 despite the persistence of the disease in a nearby untreated area. Although this decline appeared related to the control effort, it is noted that a large decline also occurred in the untreated area, suggesting the influence of other factors such as economic development or improvements in sanitation. PMID:5309511

  16. Control of schistosomiasis in Guayama and Arroyo, Puerto Rico.

    Science.gov (United States)

    Jobin, W R; Ferguson, F F; Palmer, J R

    1970-01-01

    In 1953, a programme to control schistosomiasis mansoni was started in Guayama and Arroyo, Puerto Rico, employing, first, chemical and, later, both biological and chemical methods to control Biomphalaria glabrata, the snail host of Schistosoma mansoni. Sodium pentachlorophenate was the molluscicide, and an ampullarid snail, Marisa cornuarietis, was used for biological control in ponds and reservoirs. In addition some chemotherapy was given to infected persons. The prevalence of intestinal schistosomiasis was measured annually, sampling about one-third of the 6-year-old population in Guayama and Arroyo and in Caguas, an untreated area. Costs of the programme and the results are discussed in relation to similar projects in other parts of Puerto Rico. In Guayama and Arroyo the prevalence of schistosomiasis reached zero in 6-year-olds by 1966 despite the persistence of the disease in a nearby untreated area. Although this decline appeared related to the control effort, it is noted that a large decline also occurred in the untreated area, suggesting the influence of other factors such as economic development or improvements in sanitation.

  17. El sustrato histórico del euroescepticismo checo

    Directory of Open Access Journals (Sweden)

    Daniel Esparza

    2012-01-01

    Full Text Available Este artículo examina el sustrato histórico del que se nutre el euroescepticismo checo. Se trata de un segmento apenas explorado que se aborda desde un marco teórico que estudia la relación entre la identidad nacional y el Otro. La identidad se construye a través de las sucesivas identificaciones "simbólicas e imaginarias" con Otros relevantes. Dichas identificaciones pueden ser tanto positivas como negativas. Para clasificar dichas identificaciones hacia la UE, cualitativamente, se proponen cuatro criterios básicos: "democracia", "economía", "seguridad" e "identidad nacional". Las fuentes utilizadas son los discursos del presidente Václav Klaus y los programas electorales del ODS y KSCM. Una de las conclusiones sugiere que las identifi caciones negativas hacia la UE están asociadas a reminiscencias de relaciones traumáticas con potencias del pasado, como la URSS, Alemania o el imperio Habsburgo.

  18. Introduction to nonlinear dispersive equations

    CERN Document Server

    Linares, Felipe

    2015-01-01

    This textbook introduces the well-posedness theory for initial-value problems of nonlinear, dispersive partial differential equations, with special focus on two key models, the Korteweg–de Vries equation and the nonlinear Schrödinger equation. A concise and self-contained treatment of background material (the Fourier transform, interpolation theory, Sobolev spaces, and the linear Schrödinger equation) prepares the reader to understand the main topics covered: the initial-value problem for the nonlinear Schrödinger equation and the generalized Korteweg–de Vries equation, properties of their solutions, and a survey of general classes of nonlinear dispersive equations of physical and mathematical significance. Each chapter ends with an expert account of recent developments and open problems, as well as exercises. The final chapter gives a detailed exposition of local well-posedness for the nonlinear Schrödinger equation, taking the reader to the forefront of recent research. The second edition of Introdu...

  19. Dispersivity in heterogeneous permeable media

    International Nuclear Information System (INIS)

    Chesnut, D.A.

    1994-01-01

    When one fluid displaces another through a one-dimensional porous medium, the composition changes from pure displacing fluid at the inlet to pure displaced fluid some distance downstream. The distance over which an arbitrary percentage of this change occurs is defined as the mixing zone length, which increases with increasing average distance traveled by the displacement front. For continuous injection, the mixing zone size can be determined from a breakthrough curve as the time required for the effluent displacing fluid concentration to change from, say, 10% to 90%. In classical dispersion theory, the mixing zone grows in proportion to the square root of the mean distance traveled, or, equivalently, to the square root of the mean breakthrough time. In a multi-dimensional heterogeneous medium, especially at field scales, the size of the mixing zone grows almost linearly with mean distance or travel time. If an observed breakthrough curve is forced to fit the, clinical theory, the resulting effective dispersivity, instead of being constant, also increases almost linearly with the spatial or temporal scale of the problem. This occurs because the heterogeneity in flow properties creates a corresponding velocity distribution along the different flow pathways from the inlet to the outlet of the system. Mixing occurs mostly at the outlet, or wherever the fluid is sampled, rather than within the medium. In this paper, we consider the effects. of this behavior on radionuclide or other contaminant migration

  20. Dispersivity in heterogeneous permeable media

    International Nuclear Information System (INIS)

    Chesnut, D.A.

    1994-01-01

    When one fluid displaces another through a one-dimensional porous medium, the composition changes from pure displacing fluid at the inlet to pure displaced fluid some distance downstream. The distance over which an arbitrary percentage (typically 80%) of this change occurs is defined as the mixing zone length, which increases with increasing average distance traveled by the displacement front. Alternatively, for continuous injection, the mixing zone size can be determined from a breakthrough curve as the time required for the effluent displacing fluid concentration to change from, say, 10% to 90%. In classical dispersion theory, the mixing zone grows in proportion to the square root of the mean distance traveled, or, equivalently, to the square root of the mean breakthrough time. In a multi-dimensional heterogeneous medium, especially at field scales, the size of the mixing zone grows almost linearly with mean distance or travel time. If an observed breakthrough curve is forced to fit the classical theory, the resulting effective dispersivity, instead of being constant, also increases almost linearly with the spatial or temporal scale of the problem. This occurs because the heterogeneity in flow properties creates a corresponding velocity distribution along the different flow pathways from the inlet to the outlet of the system. Mixing occurs mostly at the outlet, or wherever the fluid is sampled, rather than within the medium. In this paper, we consider the effects of this behavior on radionuclide or other contaminant migration

  1. Benthic Habitats of Puerto Rico and the U.S. Virgin Islands;Photomosaic of Puerto Rico (Isla de Vieques), 1999

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Habitat maps of Puerto Rico and the U.S. Virgin Islands were created by visual interpretation of aerial photographs using the Habitat Digitizer Extension. Aerial...

  2. A laboratory dispersant effectiveness test which reflects dispersant efficiency in the field

    International Nuclear Information System (INIS)

    Lunel, T.; Wood, P.

    1996-01-01

    Oil dispersion efficiencies of surfactants, from laboratory dispersion tests and field data were compared and calibrated. Data from an oil spill, where dispersants were used as a major part of the response, was analysed. The data was accumulated through the monitoring of the dispersant operation of the Sea Empress spill incident, in which Forties Blend oil was spilled at sea. This detailed data set was used to calibrate existing laboratory dispersant tests, and to devise a new International Dispersant Effectiveness Test. The objective was to create a comprehensive guide to decision making on whether and when to start a dispersant spraying operation. The dispersion efficiencies obtained from the laboratory dispersant tests were compared with field data. Flume tests produced the highest percentage of dispersed oil for all the dispersal tests. However, it was emphasised that the total percentage of oil dispersed should not be the only measure of dispersant effectiveness, since it does not distinguish between the contribution of natural and chemically enhanced dispersion. 9 refs., 1 tab., 9 figs

  3. A dendrochronological study of teak (Tectona grandis L. f., Verbenaceae) in Puerto Rico

    Science.gov (United States)

    Margaret S. Devall; Bernard R. Parresol

    2003-01-01

    In Puerto Rico, an island in the West Indies, large areas of primary forest have been cut and converted to farmland or to secondary forest; subsequently the farmlands declined in fertility and were abandoned. Various tree species were planted in order to restore the degraded land and to provide timber. Teak is a species with great restoration potential in Puerto Rico...

  4. 40 CFR 52.2723 - EPA-approved Puerto Rico regulations.

    Science.gov (United States)

    2010-07-01

    ... EPA-approved Puerto Rico regulations. Regulation for the Control of Atmospheric Pollution Puerto Rico... Methods 9/28/95 ......do Rule 107—Air Pollution Emergencies 9/28/95 ......do Rule 108—Air Pollution Control Equipment 9/28/95 ......do Rule 109—Notice of Violation 9/28/95 ......do Rule 110—Revision of...

  5. Puerto Rico School Principals: Leadership Perceptions and Practices in Schools in Need of Improvement

    Science.gov (United States)

    Gonzalez, Jacqueline Bocachica

    2016-01-01

    The phenomenon of school leadership in Puerto Rico is explored in this study, which was an examination of the perceptions and practices of 12 elementary school principals. Puerto Rico is a U.S. territory that functions within a unique political structure yet is held to the same standards as all U.S. districts. The primary method of data collection…

  6. QUANTIFYING SEDIMENT CONTRIBUTIONS TO THE GUÁNICA BAY PUERTO RICO

    Science.gov (United States)

    The island of Puerto Rico faces considerable challenges regarding sustainable land use and effects of land use on adjacent freshwater and marine ecosystem services. In watersheds feeding Guánica Bay (southwestern Puerto Rico), increased soil erosion and sediment loading to strea...

  7. 33 CFR 165.771 - Safety Zone; Bahia de Ponce, Puerto Rico

    Science.gov (United States)

    2010-07-01

    ..., Puerto Rico 165.771 Section 165.771 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... Zone; Bahia de Ponce, Puerto Rico (a) Location. The following area is established as a safety zone... Bahia de Ponce, on approach to or departure from the Puerto de Ponce waterfront facility in Bahia de...

  8. 33 CFR 165.758 - Security Zone; San Juan, Puerto Rico.

    Science.gov (United States)

    2010-07-01

    ... Security Zone; San Juan, Puerto Rico. (a) Location. Moving and fixed security zones are established 50... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Security Zone; San Juan, Puerto Rico. 165.758 Section 165.758 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND...

  9. 33 CFR 165.778 - Security Zone; Port of Mayaguez, Puerto Rico.

    Science.gov (United States)

    2010-07-01

    ..., Puerto Rico. 165.778 Section 165.778 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... Security Zone; Port of Mayaguez, Puerto Rico. (a) Security zone. A moving and fixed security zone is established around all cruise ships entering, departing, mooring, or anchoring in the Port of Mayaguez, Puerto...

  10. The Puerto Rico Gap Analysis Project Volume 1: land cover, vertebrate species distributions, and land stewardship

    Science.gov (United States)

    W. A. Gould; C. Alarcon; B. Fevold; M.E. Jimenez; S. Martinuzzi; G. Potts; M. Quinones; M. Solórzano; E. Ventosa

    2008-01-01

    Puerto Rico faces a number of problems common to much of the world. Population is increasing while land area is not, and there are reassessments of land use policy and practice to accommodate growing populations, shifting economies, and changing public value systems. Puerto Rico shares similarities with the Eastern United States with its history of agricultural...

  11. Language Policy in Puerto Rico's Higher Education: Opening the Door for Translanguaging Practices

    Science.gov (United States)

    Carroll, Kevin S.; Mazak, Catherine M.

    2017-01-01

    This paper investigates the relationship between meso university language policies in Puerto Rico and their micro instantiations in an undergraduate psychology classroom. We describe a typology of language policies used by 38 universities and campuses in Puerto Rico where their openness allows for flexible implementation of everyday micro policy.…

  12. Is English a Language Barrier to Public Higher Education in Puerto Rico?

    Science.gov (United States)

    Bischoff, Shannon

    2017-01-01

    The goal of this paper was to address the question, "Have the austerity measures enacted due to the global economic crisis impacted student enrollments at the University of Puerto Rico Mayagüez?" as Rodríguez (2011. "Social protest and the future of Higher Education in Puerto Rico." "Academe" 97(4).…

  13. Pollen Forecast and Dispersion Modelling

    Science.gov (United States)

    Costantini, Monica; Di Giuseppe, Fabio; Medaglia, Carlo Maria; Travaglini, Alessandro; Tocci, Raffaella; Brighetti, M. Antonia; Petitta, Marcello

    2014-05-01

    The aim of this study is monitoring, mapping and forecast of pollen distribution for the city of Rome using in-situ measurements of 10 species of common allergenic pollens and measurements of PM10. The production of daily concentration maps, associated to a mobile phone app, are innovative compared to existing dedicated services to people who suffer from respiratory allergies. The dispersal pollen is one of the most well-known causes of allergic disease that is manifested by disorders of the respiratory functions. Allergies are the third leading cause of chronic disease and it is estimated that tens millions of people in Italy suffer from it. Recent works reveal that during the last few years there was a progressive increase of affected subjects, especially in urban areas. This situation may depend: on the ability to transport of pollutants, on the ability to react between pollutants and pollen and from a combination of other irritants, existing in densely populated and polluted urban areas. The methodology used to produce maps is based on in-situ measurements time series relative to 2012, obtained from networks of air quality and pollen stations in the metropolitan area of Rome. The monitoring station aerobiological of University of Rome "Tor Vergata" is located at the Department of Biology. The instrument used to pollen monitoring is a volumetric sampler type Hirst (Hirst 1952), Model 2000 VPPS Lanzoni; the data acquisition is carried out as reported in Standard UNI 11008:2004 - "Qualità dell'aria - Metodo di campionamento e conteggio dei granuli pollinici e delle spore fungine aerodisperse" - the protocol that describes the procedure for measuring of the concentration of pollen grains and fungal spores dispersed into the atmosphere, and reported in the "Manuale di gestione e qualità della R.I.M.A" (Travaglini et. al. 2009). All 10 allergenic pollen are monitored since 1996. At Tor Vergata university is also operating a meteorological station (SP2000, CAE

  14. Tomography with energy dispersive diffraction

    Science.gov (United States)

    Stock, S. R.; Okasinski, J. S.; Woods, R.; Baldwin, J.; Madden, T.; Quaranta, O.; Rumaiz, A.; Kuczewski, T.; Mead, J.; Krings, T.; Siddons, P.; Miceli, A.; Almer, J. D.

    2017-09-01

    X-ray diffraction can be used as the signal for tomographic reconstruction and provides a cross-sectional map of the crystallographic phases and related quantities. Diffraction tomography has been developed over the last decade using monochromatic x-radiation and an area detector. This paper reports tomographic reconstruction with polychromatic radiation and an energy sensitive detector array. The energy dispersive diffraction (EDD) geometry, the instrumentation and the reconstruction process are described and related to the expected resolution. Results of EDD tomography are presented for two samples containing hydroxyapatite (hAp). The first is a 3D-printed sample with an elliptical crosssection and contains synthetic hAp. The second is a human second metacarpal bone from the Roman-era cemetery at Ancaster, UK and contains bio-hAp which may have been altered by diagenesis. Reconstructions with different diffraction peaks are compared. Prospects for future EDD tomography are also discussed.

  15. Determination of dispersity of crushed granite

    International Nuclear Information System (INIS)

    Liu Dejun; Fan Xianhua; Zhang Yingjie; Yao Jun; Zhou Duo; Wang Yong

    2004-01-01

    The experimental crushed granite column breakthrough curves, using 99 Tc as spike tracer and 3 H as invariant tracer, are analyzed by different linear regression techniques. Dispersity of crushed granite and retardation factor of 99 TcO 4 - on the crushed granite are determined simultaneously by one linear regression technique. Dispersity of crushed granite is also obtained with 3 H as invariant tracer by the other linear regression technique. The dispersities found by spike source and invariant source methods are compared. The experimental results show that the dispersity found by spike source method is close to that found by invariant source method. It indicates that dispersity is only the characteristic of dispersion medium

  16. Determination of dispersity of crushed granite

    International Nuclear Information System (INIS)

    Liu, D.J.; Fan, X.H.

    2005-01-01

    Experimental crushed granite column breakthrough curves, using 99 Tc as spike tracer and 3 H as invariant tracer, were analyzed by different linear regression techniques. Dispersity of crushed granite and the retardation factor of 99 TcO 4 - on the crushed granite were determined simultaneously by one linear regression. Dispersity of crushed granite was also obtained with 3 H as invariant tracer by the other linear regression. The dispersities found by spike source and invariant source methods are compared. Experimental results show that the dispersity found by the spike source method is close to that found by the invariant source method. This indicates that dispersity is only a characteristic of the dispersion medium. (author)

  17. Integrating individual movement behaviour into dispersal functions.

    Science.gov (United States)

    Heinz, Simone K; Wissel, Christian; Conradt, Larissa; Frank, Karin

    2007-04-21

    Dispersal functions are an important tool for integrating dispersal into complex models of population and metapopulation dynamics. Most approaches in the literature are very simple, with the dispersal functions containing only one or two parameters which summarise all the effects of movement behaviour as for example different movement patterns or different perceptual abilities. The summarising nature of these parameters makes assessing the effect of one particular behavioural aspect difficult. We present a way of integrating movement behavioural parameters into a particular dispersal function in a simple way. Using a spatial individual-based simulation model for simulating different movement behaviours, we derive fitting functions for the functional relationship between the parameters of the dispersal function and several details of movement behaviour. This is done for three different movement patterns (loops, Archimedean spirals, random walk). Additionally, we provide measures which characterise the shape of the dispersal function and are interpretable in terms of landscape connectivity. This allows an ecological interpretation of the relationships found.

  18. Single-particle dispersion in compressible turbulence

    Science.gov (United States)

    Zhang, Qingqing; Xiao, Zuoli

    2018-04-01

    Single-particle dispersion statistics in compressible box turbulence are studied using direct numerical simulation. Focus is placed on the detailed discussion of effects of the particle Stokes number and turbulent Mach number, as well as the forcing type. When solenoidal forcing is adopted, it is found that the single-particle dispersion undergoes a transition from the ballistic regime at short times to the diffusive regime at long times, in agreement with Taylor's particle dispersion argument. The strongest dispersion of heavy particles is announced when the Stokes number is of order 1, which is similar to the scenario in incompressible turbulence. The dispersion tends to be suppressed as the Mach number increases. When hybrid solenoidal and compressive forcing at a ratio of 1/2 is employed, the flow field shows apparent anisotropic property, characterized by the appearance of large shock wave structures. Accordingly, the single-particle dispersion shows extremely different behavior from the solenoidal forcing case.

  19. Membranes as separators of dispersed emulsion phases

    OpenAIRE

    Lefferts, A.G.

    1997-01-01

    The reuse or discharge of industrial waste waters, containing small fractions of dispersed oil, requires a purification treatment for which membranes can be used. If only little oil is present, removal of the dispersed phase might be preferable to the more commonly applied removal of the continuous phase. For this purpose dispersed phase separators can be applied, which combine the features of conventional coalescers and membrane filtration. The membrane surface promotes coalescence ...

  20. Formulation of disperse systems science and technology

    CERN Document Server

    Tadros, Tharwat F

    2014-01-01

    This book presents comprehensively the science and technology behind the formulation of disperse systems like emulsions, suspensions, foams and others. Starting with a general introduction, the book covers a broad range of topics like the role of different classes of surfactants, stability of disperse systems, formulation of different dispersions, evaluation of formulations and many more. Many examples are included, too. Written by the experienced author and editor Tharwart Tadros, this book is indispensable for every scientist working in the field.

  1. Key factors for UV curable pigment dispersions

    International Nuclear Information System (INIS)

    Magny, B.; Pezron, E.; Ciceron, P.H.; Askienazy, A.

    1999-01-01

    UV oligomers with good pigment dispersion are needed to allow good formulation flexibility and possibility to apply thinner films. Pigment dispersion mainly depends on three phenomena: the wetting of agglomerates, the breakage of agglomerates by mechanical stress and the stabilization of smaller agglomerates and primary particles against flocculation. It has been shown that oligomers with low viscosity and low surface tension induce a good pigment wetting. Examples of monomers and oligomers for good pigment dispersion are given

  2. A peripheral artery disease screening study in Puerto Rico.

    Science.gov (United States)

    Delgado-Osorio, Héctor; Franqui-Rivera, Hilton; García-Palmieri, Mario R; Díaz-Santana, Mary V; Alvarez, Mario

    2011-01-01

    Peripheral artery disease (PAD) of the lower extremities is frequently underdiagnosed and undertreated. The results of screening for PAD in adults attending outpatient clinics at different sites in Puerto Rico from 2007 to 2010 are presented. A total of 33 outpatients screening clinics were conducted at different sites throughout the Island. Following the ACC/AHA Guideline recommendations, asymptomatic patients who qualified were screened for PAD using the ankle-brachial index (ABI). An ABI diabetes mellitus, and dyslipidemia are known key factors in development of PAD. Practicing physicians must be aware of the importance of an early diagnosis of PAD, particularly in the asymptomatic patient, so as to institute preventive and management measures.

  3. Ecological review of hydroelectric reservoirs in Puerto Rico

    Energy Technology Data Exchange (ETDEWEB)

    Jobin, W.R.; Ferguson, F.F.; Brown, R.

    1976-10-01

    A review of published literature and available data on the ecology of hydroelectric reservoirs and other lakes in Puerto Rico yielded various studies on unrelated elements in the aquatic ecology, but very few comprehensive investigations. The majority of the island-wide studies pertained to surveys on snails related to the parasitic disease bilharzia. A survey of 28 major lakes in 1976 showed that Biomphalaria glabrata had gradually been displaced from most of the lakes by Marisa cornuarietis and Tarebia granifera, two foreign snails which do not transmit bilharzia. Of the 17 lakes containing B. glabrata in 1956, only 8 remained infested in 1966 and only 5 in 1976, twenty years after the introduction of Marisa cornuarietis. Although the trend indicates that the lakes may be safe from transmission a monitoring system is necessary before the lakes could be used for recreation.

  4. Archivo histórico de la Casa de Moneda

    Directory of Open Access Journals (Sweden)

    Boletín Cultural y Bibliográfico Banco de la República

    1996-09-01

    Full Text Available El Banco de la República posee una de las colecciones más interesantes a nivel histórico y económico del país: el archivo de la Casa de Moneda que data de 1620. Su descripción y clasificación se comenzó en 1991 teniendo como base la Historia de la Casa de Moneda, de Antonio Barriga Villalba -administrador de la Casa en los años cincuenta-, siendo la única obra que se ha publicado hasta la fecha. La clasificación se ha realizado con base en la Norma general para la descripción archivística elaborada por el Archivo General de la Nación.

  5. La lectura hipermedial. Hacia un marco teórico

    Directory of Open Access Journals (Sweden)

    Zamora Suárez, Liliana

    2016-02-01

    Full Text Available El objetivo de este trabajo es establecer el marco teórico hacia un aprendizaje significativo durante la lectura hipermedial teniendo en cuenta los procesos cognitivos que se ponen en marcha en el transcurso de la práctica lectora. El texto hipermedial se caracteriza por su falta de linealidad y por un lenguaje enriquecido con imágenes, vídeos y sonidos lo que puede causar sobrecarga en la memoria de trabajo, atención dividida y falta de coherencia afectando, en definitiva, la comprensión lectora. Por tanto, es preciso seleccionar los documentos de forma adecuada, así como instruir al aprendiente en estrategias lectoras y de gestión digital que le permitan llevar a cabo la lectura de forma reflexiva y consciente para llegar a un aprendizaje significativo.

  6. New Heroic Figure: Female Protestors and Precarity in Puerto Rico

    Directory of Open Access Journals (Sweden)

    Guillermo Rebollo Gil

    2016-06-01

    Full Text Available This paper offers a critical look on an isolated, failed incident of protest carried out by a young Puerto Rican woman and her two children. In doing so, it explores the possibilities of radical political thought and action on the island. Furthermore, by situating this event within the larger context of danger—physical, social and discursive—that women in Puerto Rico are subjected to, it seeks to question the manner in which female protestors’ vulnerability and agency challenge those on the left to formulate gender-progressive strategies for emancipation. Lastly, it is argued here that this protestor features as new type of radical political subject on the island that could very well serve as a figurehead for large-scale social movements arising from a shared sense of precarity.

  7. Sistema de prototipos para control numérico

    Directory of Open Access Journals (Sweden)

    Abdón Sánchez Sossa

    1992-05-01

    Full Text Available La mejor utilización de equipos de alta tecnología implica el contar con el adecuado entrenamiento. La conformaci6n del Grupo de Control Numérico Computarizado de Ingenierfa de Sistemas en 1987, pionero, al permitir canalizar y consolidar en tres cursos electivos interdisciplinarios una respuesta a las inquietudes académico-docentes de apoyo al sector manufacturero. El desarrollo de varios programas, cuya complejidad ha venido creciendo con el tiempo, permitió explorar la aplicabilidad de los conceptos presentados en clase y sirvió de vinculo con la realidad Nacional de manera activa y comprometida, con el desarrollo del país. Los programas descritos en este trabajo son el resultado de muchas horas de labor y realizados contando con un exiguo presupuesto.

  8. Guanophilic fungi in three caves of southwestern Puerto Rico

    Directory of Open Access Journals (Sweden)

    Nieves-Rivera Angel M.

    2009-01-01

    Full Text Available Fifty species of guanophilic (bat guano-loving fungi were isolated from field-collected samples within three caves in southwesternPuerto Rico; most were mitosporic fungi (23 species. The caves studied were Cueva La Tuna (Cabo Rojo, Cueva de Malano(Sistema de Los Chorros, San Germán, and Cueva Viento (El Convento Cave-Spring System, Guayanilla-Peñuelas. The mostconspicuous fungus by far was the zygomycete Circinella umbellata (Mucorales. Circinella umbellata dominated the bat guanoincubation chambers (Petri dishes lined with sterile filter paper moistened with sterile water at ambient laboratory conditions.Nineteen species of basidiomycetes (e.g., Ganoderma cf. resinaceum, Geastrum cf. minimum, Lepiota sp., Polyporus sp., Ramariasp. and three species of ascomycetes (Hypoxylon sp., Xylaria anisopleura, and X. kegeliana were also recorded. They were foundon soil, rotting leaves, bark and rotting wood, buried in bat guano located below natural skylights or sinkholes.

  9. Family Assistance for Older Adults in Puerto Rico

    Directory of Open Access Journals (Sweden)

    Paul-Jesús Fericelli

    2013-09-01

    Full Text Available Global aging is a growing issue in most countries, including Puerto Rico. The well being of the older adult population depends mainly on a collaborative government initiative that uses both public assistance and the engagement of family members. Puerto Rican policymakers are searching for alternatives to care for the expanding elderly population as well as to protect the country’s economy, avoid the financial cliff, and reduce the high cost of public assistance. The purpose of this article is to analyze The Act for the Improvement of the Family Assistance and for the Support of the Elderly, Act No. 193 of 2002, under the criteria-based model (Gallagher & Haskins, 1984 with a value-critical appraisal (Chambers & Wedel, 2009. I suggest Act No. 193 of 2002 as a model for policymakers who are seeking ways to improve assistance for older adults, by promoting the following values: fairness, familism, fraternity, and accountability.

  10. Liquid agents for dispersion of hard alloys

    International Nuclear Information System (INIS)

    Putintseva, M.N.

    2006-01-01

    Effects of dispersant properties on granulometric, chemical, and phase composition of the products of WC hard alloy electroerosion are considered. It is established that an increase of liquid dispersant permittivity results in enhanced powder dispersity, and an increase of boiling temperature and kinematic viscosity of a hydrocarbon liquid promotes a carbon loss from WC and intensifies pyrolysis of the liquid.On electroerosion of WC base hard alloy in oil a powder particle consists of b-WC+W 2 C phases, in kerosine - of a-WC+b-WC, in distilled water - of W+W 2 C. The viscosity of liquid dispersants practically has no effect on powder particle size [ru

  11. Dispersal of Engineered Male Aedes aegypti Mosquitoes.

    Science.gov (United States)

    Winskill, Peter; Carvalho, Danilo O; Capurro, Margareth L; Alphey, Luke; Donnelly, Christl A; McKemey, Andrew R

    2015-11-01

    Aedes aegypti, the principal vector of dengue fever, have been genetically engineered for use in a sterile insect control programme. To improve our understanding of the dispersal ecology of mosquitoes and to inform appropriate release strategies of 'genetically sterile' male Aedes aegypti detailed knowledge of the dispersal ability of the released insects is needed. The dispersal ability of released 'genetically sterile' male Aedes aegypti at a field site in Brazil has been estimated. Dispersal kernels embedded within a generalized linear model framework were used to analyse data collected from three large scale mark release recapture studies. The methodology has been applied to previously published dispersal data to compare the dispersal ability of 'genetically sterile' male Aedes aegypti in contrasting environments. We parameterised dispersal kernels and estimated the mean distance travelled for insects in Brazil: 52.8 m (95% CI: 49.9 m, 56.8 m) and Malaysia: 58.0 m (95% CI: 51.1 m, 71.0 m). Our results provide specific, detailed estimates of the dispersal characteristics of released 'genetically sterile' male Aedes aegypti in the field. The comparative analysis indicates that despite differing environments and recapture rates, key features of the insects' dispersal kernels are conserved across the two studies. The results can be used to inform both risk assessments and release programmes using 'genetically sterile' male Aedes aegypti.

  12. Effectiveness of dispersants on thick oil slicks

    International Nuclear Information System (INIS)

    Ross, S.; Belore, R.

    1993-01-01

    Experiments were conducted to determine the relationship between dispersant effectiveness and oil slick thickness, and thereby determine the optimum time for applying dispersant onto spilled oil at sea. Tests were completed at a lab-scale level by varying the three parameters of oil type, dispersant application, and oil thickness. The tests were intended to be comparative only. The primary oils used were Alberta sweet mix blend and Hibernia B-27 crude. The dispersant, Corexit 9527, was applied either premixed with the oil, dropwise in one application, or dropwise in multiple applications to simulate a multi-hit aircraft operation. The apparatus used in the experiment was an oscillating hoop tank, with oil-containing rings used to obtain and maintain uniform slick thickness. The results indicate that the effectiveness potential of a chemical dispersant does not decrease as slick thickness increases. In fact, results of the tests involving Hibernia oil suggest that oils that tend to herd easily would be treated more effectively if dispersant were applied when the oil was relatively thick (1 mm or greater) to avoid herding problems. The oil slicks premixed with dispersant did not disperse well in the thick oil tests, not because of dispersant-oil interaction problems but because of reduced mixing energy. 6 refs., 4 figs., 1 tab

  13. Modelling airborne dispersion of coarse particulate material

    International Nuclear Information System (INIS)

    Apsley, D.D.

    1989-03-01

    Methods of modelling the airborne dispersion and deposition of coarse particulates are presented, with the emphasis on the heavy particles identified as possible constituents of releases from damaged AGR fuel. The first part of this report establishes the physical characteristics of the irradiated particulate in airborne emissions from AGR stations. The second part is less specific and describes procedures for extending current dispersion/deposition models to incorporate a coarse particulate component: the adjustment to plume spread parameters, dispersion from elevated sources and dispersion in conjunction with building effects and plume rise. (author)

  14. A comparative study of stream water and stream sediment as geochemical exploration media in the Rio Tanama porphyry copper district, Puerto Rico

    Science.gov (United States)

    Learned, R.E.; Chao, T.T.; Sanzolone, R.F.

    1985-01-01

    To test the relative effectiveness of stream water and sediment as geochemical exploration media in the Rio Tanama porphyry copper district of Puerto Rico, we collected and subsequently analyzed samples of water and sediment from 29 sites in the rivers and tributaries of the district. Copper, Mo, Pb, Zn, SO42-, and pH were determined in the waters; Cu, Mo, Pb, and Zn were determined in the sediments. In addition, copper in five partial extractions from the sediments was determined. Geochemical contrast (anomaly-to-background quotient) was the principal criterion by which the effectiveness of the two media and the five extractions were judged. Among the distribution patterns of metals in stream water, that of copper most clearly delineates the known porphyry copper deposits and yields the longest discernable dispersion train. The distribution patterns of Mo, Pb, and Zn in water show little relationship to the known mineralization. The distribution of SO42- in water delineates the copper deposits and also the more extensive pyrite alteration in the district; its recognizable downstream dispersion train is substantially longer than those of the metals, either in water or sediment. Low pH values in small tributaries delineate areas of known sulfide mineralization. The distribution patterns of copper in sediments clearly delineate the known deposits, and the dispersion trains are longer than those of copper in water. The partial determinations of copper related to secondary iron and manganese oxides yield the strongest geochemical contrasts and longest recognizable dispersion trains. Significantly high concentrations of molybdenum in sediments were found at only three sites, all within one-half km downstream of the known copper deposits. The distribution patterns of lead and zinc in sediments are clearly related to the known primary lead-zinc haloes around the copper deposits. The recognizable downstream dispersion trains of lead and zinc are shorter than those of

  15. 7 CFR 319.73-3 - Conditions for transit movement of certain products through Puerto Rico or Hawaii.

    Science.gov (United States)

    2010-01-01

    ... through Puerto Rico or Hawaii. 319.73-3 Section 319.73-3 Agriculture Regulations of the Department of... or Hawaii. (a) Mail. Samples of unroasted coffee that are transiting Hawaii or Puerto Rico en route.... These samples must be returned to origin or forwarded to a destination outside Hawaii or Puerto Rico in...

  16. 76 FR 1192 - Notice of a Change in Status of an Extended Benefit (EB) Period for Puerto Rico

    Science.gov (United States)

    2011-01-07

    ... Extended Benefit (EB) Period for Puerto Rico AGENCY: Employment and Training Administration, Labor. ACTION... Puerto Rico. The following change has occurred since the publication of the last notice regarding the State's EB status: Puerto Rico's 13-week IUR has fallen below the 6% threshold and does not equal or...

  17. Does an ant-dispersed plant, Viola reichenbachiana, suffer from reduced seed dispersal under inundation disturbances?

    NARCIS (Netherlands)

    Prinzing, A.; Dauber, J.; Hammer, E.; Hammouti, N.; Bohning-Gaese, K.

    2008-01-01

    Many plant species use ants as seed dispersers. This dispersal mode is considered to be susceptible to disturbances, but the effect of natural, small-scale disturbances is still unknown. We investigated how small-scale disturbances due to inundation affect seed dispersal in Viola reichenbachiana, a

  18. Dispersed and decentralised settlement system

    Directory of Open Access Journals (Sweden)

    Andrej Černe

    2004-01-01

    Full Text Available In the process of reintegration of the urban system new settlements are emerging on theurban rim, transitional zones are reurbanised, derelict areas within the cities are being developedand degraded urban areas of derelict industrial complexes are being renaturalised. Inthe periphery combined research and production parks are being set up, in the open landscapeintegrated business, trade and recreational centres are springing up. Decentralisationand recentralisation of focal points of development accompany the contemporary processesof reurbanisation and suburbanisation – they are simultaneous and move in two-direction i.e. to and from the city. We understand them as manifestation of a dynamic balance amongcontradiction existing between the centre and the rim. Deindustrialisation and relocation ofproduction and distribution from the centres of gravity to the periphery generate extensivedegraded urban areas within cities and between the city and suburbs. The periphery is beingurbanised with the creation of new, dispersed and nonhierachical poles of development, andthe city and inner city is undergoing reurbanization. The general environmental conditionsin the city and in the countryside are being equalised, the potentials of development arebeing sought in the comparative advantages of local conditions: be it attractive urban districts,be it suburban entities or countryside areas.

  19. Databases of surface wave dispersion

    Directory of Open Access Journals (Sweden)

    L. Boschi

    2005-06-01

    Full Text Available Observations of seismic surface waves provide the most important constraint on the elastic properties of the Earth’s lithosphere and upper mantle. Two databases of fundamental mode surface wave dispersion were recently compiled and published by groups at Harvard (Ekström et al., 1997 and Utrecht/Oxford (Trampert and Woodhouse, 1995, 2001, and later employed in 3-d global tomographic studies. Although based on similar sets of seismic records, the two databases show some significant discrepancies. We derive phase velocity maps from both, and compare them to quantify the discrepancies and assess the relative quality of the data; in this endeavour, we take careful account of the effects of regularization and parametrization. At short periods, where Love waves are mostly sensitive to crustal structure and thickness, we refer our comparison to a map of the Earth’s crust derived from independent data. On the assumption that second-order effects like seismic anisotropy and scattering can be neglected, we find the measurements of Ekström et al. (1997 of better quality; those of Trampert and Woodhouse (2001 result in phase velocity maps of much higher spatial frequency and, accordingly, more difficult to explain and justify geophysically. The discrepancy is partly explained by the more conservative a priori selection of data implemented by Ekström et al. (1997. Nevertheless, it becomes more significant with decreasing period, which indicates that it could also be traced to the different measurement techniques employed by the authors.

  20. Pay Dispersion and Performance in Teams

    DEFF Research Database (Denmark)

    Bucciol, Alessandro; Foss, Nicolai J; Piovesan, Marco

    2014-01-01

    Extant research offers conflicting predictions about the effect of pay dispersion on team performance. We collected a unique dataset from the Italian soccer league to study the effect of intra-firm pay dispersion on team performance, under different definitions of what constitutes a "team". This ...

  1. A new optical rotation dispersion formula

    International Nuclear Information System (INIS)

    Kimel, I.

    1981-12-01

    A new dispersion formula for the rotatory power is obtained in the framework of Kubo forlalism for transport coefficients. Unlike the well known Rosenfeld-Condon dispersion law, this formula is consistent with the free electron gas asymptotic behavior. (Author) [pt

  2. Discrete dispersion models and their Tweedie asymptotics

    DEFF Research Database (Denmark)

    Jørgensen, Bent; Kokonendji, Célestin C.

    2016-01-01

    The paper introduce a class of two-parameter discrete dispersion models, obtained by combining convolution with a factorial tilting operation, similar to exponential dispersion models which combine convolution and exponential tilting. The equidispersed Poisson model has a special place in this ap......The paper introduce a class of two-parameter discrete dispersion models, obtained by combining convolution with a factorial tilting operation, similar to exponential dispersion models which combine convolution and exponential tilting. The equidispersed Poisson model has a special place...... in this approach, whereas several overdispersed discrete distributions, such as the Neyman Type A, Pólya-Aeppli, negative binomial and Poisson-inverse Gaussian, turn out to be Poisson-Tweedie factorial dispersion models with power dispersion functions, analogous to ordinary Tweedie exponential dispersion models...... with power variance functions. Using the factorial cumulant generating function as tool, we introduce a dilation operation as a discrete analogue of scaling, generalizing binomial thinning. The Poisson-Tweedie factorial dispersion models are closed under dilation, which in turn leads to a Poisson...

  3. Seed Dispersal Potential of Asian Elephants

    DEFF Research Database (Denmark)

    Harich, Franziska K.; Treydte, Anna Christina; Ogutu, Joseph Ochieng

    2016-01-01

    Elephants, the largest terrestrial mega-herbivores, play an important ecological role in maintaining forest ecosystem diversity. While several plant species strongly rely on African elephants (Loxodonta africana; L. cyclotis) as seed dispersers, little is known about the dispersal potential of As...

  4. Interspecific nematode signals regulate dispersal behavior.

    Directory of Open Access Journals (Sweden)

    Fatma Kaplan

    Full Text Available Dispersal is an important nematode behavior. Upon crowding or food depletion, the free living bacteriovorus nematode Caenorhabditis elegans produces stress resistant dispersal larvae, called dauer, which are analogous to second stage juveniles (J2 of plant parasitic Meloidogyne spp. and infective juveniles (IJs of entomopathogenic nematodes (EPN, e.g., Steinernema feltiae. Regulation of dispersal behavior has not been thoroughly investigated for C. elegans or any other nematode species. Based on the fact that ascarosides regulate entry in dauer stage as well as multiple behaviors in C. elegans adults including mating, avoidance and aggregation, we hypothesized that ascarosides might also be involved in regulation of dispersal behavior in C. elegans and for other nematodes such as IJ of phylogenetically related EPNs.Liquid chromatography-mass spectrometry analysis of C. elegans dauer conditioned media, which shows strong dispersing activity, revealed four known ascarosides (ascr#2, ascr#3, ascr#8, icas#9. A synthetic blend of these ascarosides at physiologically relevant concentrations dispersed C. elegans dauer in the presence of food and also caused dispersion of IJs of S. feltiae and J2s of plant parasitic Meloidogyne spp. Assay guided fractionation revealed structural analogs as major active components of the S. feltiae (ascr#9 and C. elegans (ascr#2 dispersal blends. Further analysis revealed ascr#9 in all Steinernema spp. and Heterorhabditis spp. infected insect host cadavers.Ascaroside blends represent evolutionarily conserved, fundamentally important communication systems for nematodes from diverse habitats, and thus may provide sustainable means for control of parasitic nematodes.

  5. 21 CFR 178.3725 - Pigment dispersants.

    Science.gov (United States)

    2010-04-01

    ... HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: ADJUVANTS, PRODUCTION AIDS, AND SANITIZERS Certain Adjuvants and Production Aids § 178.3725 Pigment dispersants. Subject to the provisions of this... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Pigment dispersants. 178.3725 Section 178.3725 Food...

  6. Dispersions of Carbon nanotubes in Polymer Matrices

    Science.gov (United States)

    Wise, Kristopher Eric (Inventor); Park, Cheol (Inventor); Siochi, Emilie J. (Inventor); Harrison, Joycelyn S. (Inventor); Lillehei, Peter T. (Inventor); Lowther, Sharon E. (Inventor)

    2010-01-01

    Dispersions of carbon nanotubes exhibiting long term stability are based on a polymer matrix having moieties therein which are capable of a donor-acceptor complexation with carbon nanotubes. The carbon nanotubes are introduced into the polymer matrix and separated therein by standard means. Nanocomposites produced from these dispersions are useful in the fabrication of structures, e.g., lightweight aerospace structures.

  7. Membranes as separators of dispersed emulsion phases

    NARCIS (Netherlands)

    Lefferts, A.G.

    1997-01-01

    The reuse or discharge of industrial waste waters, containing small fractions of dispersed oil, requires a purification treatment for which membranes can be used. If only little oil is present, removal of the dispersed phase might be preferable to the more commonly applied removal of the

  8. A synthesis of empirical plant dispersal kernels

    Czech Academy of Sciences Publication Activity Database

    Bullock, J. M.; González, L. M.; Tamme, R.; Götzenberger, Lars; White, S. M.; Pärtel, M.; Hooftman, D. A. P.

    2017-01-01

    Roč. 105, č. 1 (2017), s. 6-19 ISSN 0022-0477 Institutional support: RVO:67985939 Keywords : dispersal kernel * dispersal mode * probability density function Subject RIV: EH - Ecology, Behaviour OBOR OECD: Ecology Impact factor: 5.813, year: 2016

  9. Interaction between molecular complexes in dispersive media

    International Nuclear Information System (INIS)

    Banagas, E.A.; Manykin, E.A.

    1987-01-01

    The interaction between molecular complexes in different dispersive media with local and nonlocal screening is investigated theoretically. On the basis of results of numerical analysis on a computer, the dependence of the coupled-system spectrum and the interaction energy of the polarized modes on the characteristic parameters of the dispersive media is considered

  10. Modeling of atmospheric dispersion of radionuclides

    International Nuclear Information System (INIS)

    Baklouti, Nada

    2010-01-01

    This work is a prediction of atmospheric dispersion of radionuclide from a chronic rejection of the nuclear power generating plant that can be located in one of the Tunisian sites: Skhira or Bizerte. Also it contains a study of acute rejection 'Chernobyl accident' which was the reference for the validation of GENII the code of modeling of atmospheric dispersion.

  11. Dispersion-induced nonlinearities in semiconductors

    DEFF Research Database (Denmark)

    Mørk, Jesper; Mecozzi, A.

    2002-01-01

    A dispersive and saturable medium is shown, under very general conditions, to possess ultrafast dynamic behaviour due to non-adiabatic polarisation dynamics. Simple analytical expressions relating the effect to the refractive index dispersion of a semiconductor ire derived and the magnitude...... of the equivalent Kerr coefficient is shown to be in qualitative agreement with measurements on active semiconductor waveguides....

  12. Modeling the dispersal of spiny lobster (

    NARCIS (Netherlands)

    Whomersley, P.; van der Molen, J.; Holt, D.; Trundle, C.; Clark, S.; Fletcher, D.

    2018-01-01

    Knowledge of larval dispersal, population dynamics and connectivity in relation to the management and conservation of commercially important species is vital if existing fisheries are to remain sustainable into the future. Larval dispersal of the commercially exploited spiny lobster, Palinurus

  13. Employment Effects of Spatial Dispersal of Refugees

    DEFF Research Database (Denmark)

    Damm, Anna Piil; Rosholm, Michael

    We argue that spatial dispersal influences labour market assimilation of refugees through two mechanisms: first, the local job offer arrival rate and, second, place utility. Our partial search model with simultaneous job and residential location search predicts that the reservation wage for local...... by evaluating the employment effects of the Danish spatial dispersal policy carried out 1986-1998....

  14. An atmospheric dispersion index for prescribed burning

    Science.gov (United States)

    Leonidas G. Lavdas

    1986-01-01

    A numerical index that estimates the atmosphere's capacity to disperse smoke from prescribed burning is described. The physical assumptions and mathematical development of the index are given in detail. A preliminary interpretation of dispersion index values is offered. A FORTRAN subroutine package for computing the index is included.

  15. Dispersive and erodible soils - fundamental differences

    CSIR Research Space (South Africa)

    Paige-Green, P

    2008-11-01

    Full Text Available Dispersive, erodible and slaking soils are prevalent over wide areas of South Africa. Each of these materials increases the cost of construction, but dispersive soils are likely to lead to far more serious problems, particularly in dam construction...

  16. Spectral dispersion and fringe detection in IOTA

    Science.gov (United States)

    Traub, W. A.; Lacasse, M. G.; Carleton, N. P.

    1990-01-01

    Pupil plane beam combination, spectral dispersion, detection, and fringe tracking are discussed for the IOTA interferometer. A new spectrometer design is presented in which the angular dispersion with respect to wavenumber is nearly constant. The dispersing element is a type of grism, a series combination of grating and prism, in which the constant parts of the dispersion add, but the slopes cancel. This grism is optimized for the display of channelled spectra. The dispersed fringes can be tracked by a matched-filter photon-counting correlator algorithm. This algorithm requires very few arithmetic operations per detected photon, making it well-suited for real-time fringe tracking. The algorithm is able to adapt to different stellar spectral types, intensity levels, and atmospheric time constants. The results of numerical experiments are reported.

  17. Pay Dispersion and Performance in Teams

    Science.gov (United States)

    Bucciol, Alessandro; Foss, Nicolai J.; Piovesan, Marco

    2014-01-01

    Extant research offers conflicting predictions about the effect of pay dispersion on team performance. We collected a unique dataset from the Italian soccer league to study the effect of intra-firm pay dispersion on team performance, under different definitions of what constitutes a “team”. This peculiarity of our dataset can explain the conflicting evidence. Indeed, we also find positive, null, and negative effects of pay dispersion on team performance, using the same data but different definitions of team. Our results show that when the team is considered to consist of only the members who directly contribute to the outcome, high pay dispersion has a detrimental impact on team performance. Enlarging the definition of the team causes this effect to disappear or even change direction. Finally, we find that the detrimental effect of pay dispersion is due to worse individual performance, rather than a reduction of team cooperation. PMID:25397615

  18. Analysis of site-specific dispersion conditions

    International Nuclear Information System (INIS)

    Paesler-Sauer, J.

    1989-03-01

    This report presents an analysis of atmospheric dispersion conditions in the environs of nuclear power stations in the Federal Republic of Germany. The analysis is based on meteorological data measured on the power station sites (KFUe = nuclear reactor remote control records) and by neighbouring stations operated by the German Weather Service. The data are series of hourly mean values of wind and temperature gradient or stability class over the period of one or more years. The aim of the data analysis is to find types of dispersion conditions characterized by the flow field and stratification, and to assess the feasibility of calculating these quantities in the case of an emergency. Influences of terrain structures in the environs of the site are considered. The annual frequencies of types of dispersion situations are assessed, the capability to recognize the dispersion situation from meteorological data measured on the site and the applicability of dispersion models are discussed. (orig.) [de

  19. Solitonic Dispersive Hydrodynamics: Theory and Observation

    Science.gov (United States)

    Maiden, Michelle D.; Anderson, Dalton V.; Franco, Nevil A.; El, Gennady A.; Hoefer, Mark A.

    2018-04-01

    Ubiquitous nonlinear waves in dispersive media include localized solitons and extended hydrodynamic states such as dispersive shock waves. Despite their physical prominence and the development of thorough theoretical and experimental investigations of each separately, experiments and a unified theory of solitons and dispersive hydrodynamics are lacking. Here, a general soliton-mean field theory is introduced and used to describe the propagation of solitons in macroscopic hydrodynamic flows. Two universal adiabatic invariants of motion are identified that predict trapping or transmission of solitons by hydrodynamic states. The result of solitons incident upon smooth expansion waves or compressive, rapidly oscillating dispersive shock waves is the same, an effect termed hydrodynamic reciprocity. Experiments on viscous fluid conduits quantitatively confirm the soliton-mean field theory with broader implications for nonlinear optics, superfluids, geophysical fluids, and other dispersive hydrodynamic media.

  20. Piroxicam y cambios ováricos de cabras adultas

    Directory of Open Access Journals (Sweden)

    Rafaela Segundo Pérez

    2016-01-01

    Full Text Available La función de los ovarios puede alterarse por inhibidores de la enzima ciclooxigenasa (COX. La aplicación de piroxicam, antiinflamatorio no esteroideo e inhibidor de COX es de amplio uso veterinario (AINE y puede alterar la función de los ovarios. El objetivo de esta investigación fue evaluar los cambios extra e intraováricos en cabras adultas en respuesta a piroxicam. En seis cabras adultas de entre 35 y 40 kg de peso vivo, se sincronizaron estros y ovulación, mediante la colocación de CIDR (dispositivo intravaginal de liberación controlada de P4 durante 11 días, al retirar el CIDR se aplicaron prostaglandinas F2α y 400 UI de eCG (inducción de la ovulación. Antes (24 h, de la inducción de ovulación al grupo testigo y tratado (n=3 se les hicieron cuatro aplicaciones intramusculares de un ml de solución salina o piroxicam (1.5 mg-1 kg de peso vivo con intervalo de 24 h. Posterior a la primera aplicación de piroxicam (144 h se extrajeron los ovarios. Se colectaron muestras sanguíneas cada 24 h; desde 48 h antes de la inducción de la ovulación y, hasta la ovariectomía. En ovario derecho e izquierdo se cuantificó el número y tamaño de folículos y cuerpos lúteos superficiales. En 16 cortes histológicos de cada ovario, se evaluaron las mismas estructuras con localización intraovárica. En suero sanguíneo se determinó la concentración sérica de progesterona (P4 y estradiol (E2. En los datos de folículos y CL se realizó la prueba de suma de rangos de Wilcoxon. Mientras que, P4 y E2 se analizaron utilizando modelos para datos con medidas repetidas (modelos mixtos lineales, los cuales fueron ajustados usando el programa estadísto R. La significancia en los resultados se consideró con α< 0.05. La aplicación de piroxicam disminuyó el número de folículos intraováricos (P< 0.0001 y el de CL intraováricos en desarrollo (P=0.04. Los niveles de P4 y E2 no se modificaron por aplicación de piroxicam (P=0.2, aunque, P4

  1. La gestión por procesos, su surgimiento y aspectos teóricos

    OpenAIRE

    Daysi Ruiz-Fuentes; Rosa Mercedes Almaguer-Torres; Isabel Cristina Torres-Torres; Alejandro Miguel Hernández-Peña

    2014-01-01

    Abordó aspectos históricos y teóricos relacionados con la gestión por procesos, se precisa las potencialidades de su aplicación para el perfeccionamiento de la dirección de las empresas. Presentó un análisis de diferentes definiciones de este término a partir del c ual se determinan las regularidades que lo caracterizan. Se puntualizan algunos aspectos teóricos vinculados con esta forma de gestión empresarial.

  2. Four New Ladybug Species Belonging to Decadiomus Chapin (Coleoptera: Coccinellidae) from Puerto Rico.

    Science.gov (United States)

    Segarra-Carmona, A E; Otero, M

    2014-12-01

    While searching for native natural enemies attacking invasive insect pests in Puerto Rico, we found four undescribed ladybug species belonging to the Caribbean ladybug genus Decadiomus Chapin. In this article, we describe the following species from Puerto Rico: Decadiomus seini n. sp., Decadiomus ramosi n. sp., Decadiomus hayuyai n. sp., and Decadiomus martorelli n. sp. Illustrations of the dorsal habitus, shape of prosternal carinae, and drawings of male and female genitalia are presented. We also present a key for Diomini of Puerto Rico and discuss their importance as potential biocontrol agents.

  3. Índice numérico de un espacio de Banach

    OpenAIRE

    Martín Suárez, Miguel

    2013-01-01

    El índice numérico de un espacio de Banach se define como la mayor constante de equivalencia entre el radio numérico y la norma usual en el álgebra de todos los operadores lineales y continuos sobre él. Este concepto fue introducido por G. Lumer en 1968, y estudiado por matemáticos como F. Bonsall, J. Duncan, C. McGregor, J. Pryce y A. White. En la tesis se hace un estudio sistemática de este concepto. Por una parte, se estudia el comportamiento del índice numérico respec...

  4. La gestión por procesos, su surgimiento y aspectos teóricos

    Directory of Open Access Journals (Sweden)

    Daysi Ruiz - Fuentes

    2013-01-01

    Full Text Available Abordó aspectos históricos y teóricos relacionados con la gestión por procesos, se precisa las potencialidades de su aplicación para el perfeccionamiento de la dirección de las empresas. Presentó un análisis de diferentes definiciones de este término a partir del c ual se determinan las regularidades que lo caracterizan. Se puntualizan algunos aspectos teóricos vinculados con esta forma de gestión empresarial.

  5. The migratory impact of minimum wage legislation: Puerto Rico, 1970-1987.

    Science.gov (United States)

    Santiago, C E

    1993-01-01

    "This study examines the impact of minimum wage setting on labor migration. A multiple time series framework is applied to monthly data for Puerto Rico from 1970-1987. The results show that net emigration from Puerto Rico to the United States fell in response to significant changes in the manner in which minimum wage policy was conducted, particularly after 1974. The extent of commuter type labor migration between Puerto Rico and the United States is influenced by minimum wage policy, with potentially important consequences for human capital investment and long-term standards of living." excerpt

  6. Clouds and aerosols in Puerto Rico - a new evaluation

    Science.gov (United States)

    Allan, J. D.; Baumgardner, D.; Raga, G. B.; Mayol-Bracero, O. L.; Morales-García, F.; García-García, F.; Montero-Martínez, G.; Borrmann, S.; Schneider, J.; Mertes, S.; Walter, S.; Gysel, M.; Dusek, U.; Frank, G. P.; Krämer, M.

    2008-03-01

    The influence of aerosols, both natural and anthropogenic, remains a major area of uncertainty when predicting the properties and behaviour of clouds and their influence on climate. In an attempt to better understand warm cloud formation in a tropical marine environment, a period of intensive measurements took place in December 2004 in Puerto Rico, using some of the latest developments in online instrumentation such as aerosol mass spectrometers, cloud condensation nuclei counters and a hygroscopicity tandem differential mobility analyser. Simultaneous online measurements of aerosol size distributions, composition, hygroscopicity and optical properties were made near the lighthouse of Cape San Juan in the north-eastern corner of the island and at the top of East Peak mountain (1040 m a.s.l.), the two sites separated by 17 km. Additional measurements of the cloud droplet residual and interstitial aerosol properties were made at the mountain site, accompanied by measurements of cloud droplet size distributions, liquid water content and the chemical composition of cloud and rain water samples. Both aerosol composition and cloud properties were found to be sensitive to wind sector. Air from the east-northeast (ENE) was mostly free of anthropogenic influences, the submicron fraction being mainly composed of non-sea salt sulphate, while that from the east-southeast (ESE) was found to be moderately influenced by populated islands upwind, adding smaller (residual particles and concentrations of cloudwater nitrate, sulphate and insoluble material increased during polluted conditions. Previous studies in Puerto Rico had reported the presence of a significant non-anthropogenic organic fraction in the aerosols measured and concluded that this was a factor controlling the in situ cloud properties. However, this was not observed in our case. In contrast to the 1.00±0.14 μg m-3 of organic carbon measured in 1992 and 1995, the organic matter measured in the current study of 0

  7. Almanzor: drama histórico de Blas Infante

    Directory of Open Access Journals (Sweden)

    Esquerrá Nonell, Josep

    2014-06-01

    Full Text Available The recent publication of an unpublished and original theatre play by Blas Infante: Almanzor, an unfinished historical drama written in the early 20’s of the last century, opens up possibilities of interpretation in relation to another work written in the same period, The Pedagogical Dictatorship, that has a clear intention of improving the Spain of the Restoration from a historical point of view. Almanzor is also his second play with an Andalusian theme, along with Motamid, the Last King of Seville. The play is primarily an adaptation of the History of the Muslims of Spain until the Conquest by the Almoravids of R.P. Dozy. It belongs to the dramatic form coined as poetic theater by Modernism, but the play has deep romantic roots. Infante once again recreates, the glorious past of Al-Andalus.La reciente publicación de una obra de teatro inédita y original de Blas Infante: Almanzor, drama histórico incompleto escrito hacia la primera mitad de los años 20 del siglo pasado, abre posibilidades de interpretación con respecto a otra obra escrita en el mismo periodo, La Dictadura Pedagógica, con una finalidad clara de superación de la España de la Restauración desde el punto de vista histórico. Almanzor es además su segunda obra de temática andalusí, junto con Motamid, último rey de Sevilla. La obra es, principalmente, una adaptación de la Historia de los musulmanes de España hasta la conquista de los almorávides de R. P. Dozy. Pertenece a la modalidad dramática que el Modernismo denominó teatro poético, pero la obra tiene una honda raíz romántica. Infante recrea, una vez más, el glorioso pasado de Al-Ándalus.

  8. UFOMOD - atmospheric dispersion and deposition

    International Nuclear Information System (INIS)

    Panitz, H.J.; Matzerath, C.; Paesler-Sauer, J.

    1989-10-01

    The report gives an introduction into the modelling of atmospheric dispersion and deposition which has been implemented in the new program system UFOMOD for assessing the consequences after nuclear accidents. According to the new structure of UFOMOD, different trajectory models with ranges of validity near to the site and at far distances are applied. Emphasis is laid on the description of the segmented plume model MUSEMET and its affilated submodels, being the removal of activity from the cloud by dry and wet deposition, and special effects like plume rise and the behaviour of plumes released into building wakes. In addition, the evaluation of γ-dose correction factors to take account of the finite extent of the radioactive plume in the near range (up to about 20 km) are described. Only brief introductions are given into the principles of the other models available: the puff model RIMPUFF, the long-range puff model MESOS, and the special straight-line Gaussian model ISOLA which are used if low-level long-duration releases are considered. To define starting times of weather sequences and the probabilities of occurrence of these sequences, it is convenient to perform stratified sampling. Therefore, the preprocessing program package METSAM has been developed to perform for generic ACAs a random sampling of weather sequences out off a population of classified weather conditions. The sampling procedure and a detailed input/output (I/O) description is presented and an additional appendix, respectively. A general overview on the I/O structure of MUSEMET as well as a brief user guide to run the KfK version of the MESOS code are also given in the appendix. (orig.) [de

  9. DNA capture reveals transoceanic gene flow in endangered river sharks

    OpenAIRE

    Li, Chenhong; Corrigan, Shannon; Yang, Lei; Straube, Nicolas; Harris, Mark; Hofreiter, Michael; White, William T.; Naylor, Gavin J. P.

    2015-01-01

    The river sharks of the genus Glyphis, widely feared as man-eaters throughout India, remain very poorly known to science. The group constitutes five described species, all of which are considered highly endangered and restricted to freshwater systems in Australasia and Southeast Asia. DNA sequence data derived from 19th-century dried museum material augmented with contemporary samples indicates that only three of the five currently described species are valid; that there is a genetically dist...

  10. The Braer incident: Dispersion in action

    International Nuclear Information System (INIS)

    Thomas, D.

    1993-01-01

    In January 1993, the tanker Braer foundered in the Shetland Islands and pollution from the cargo of 85,000 tonnes of Gullfaks crude oil was reported almost immediately. The tanker was battered by storm winds and finally broke up, spilling the remainder of its cargo into the bay at Garth's Ness. Dispersants were applied to the oil plumes, assisting the significant natural dispersion. Shoreline protection and cleanup activities included construction of spade dams and sorbent barriers. Oil concentrations in water, air, sediment, and fish were monitored. The sampling program undertaken during the spill period is described. Measured hydrocarbon concentrations in salmon farm areas were not observed to rise above 4 ppM. The high rates of dispersion make the Braer incident worthy of detailed study both in terms of understanding the mechanism of the dispersion process and also in assessing the environmental effects following high dispersed oil concentrations. Estimates of the spill's mass balance are provided for the bay at Garth's Ness, where the highest oil concentrations were observed, and along the 26 km of coastline which received the most significant concentrations of dispersed oil. Contrary to laboratory experiments which showed that the Gullfaks crude would emulsify at the high sea states prevailing at the time, the Braer spill did not emulsify and most of the oil released was dispersed naturally into the water column. It appears that it is most appropriate to model the Braer spill as a spillage of floating or dissolved chemical. 4 refs., 4 figs., 6 tabs

  11. Dispersion cancellation in a triple Laue interferometer

    International Nuclear Information System (INIS)

    Lemmel, Hartmut

    2014-01-01

    The concept of dispersion cancellation has been established in light optics to improve the resolution of interferometric measurements on dispersive media. Odd order dispersion cancellation allows to measure phase shifts without defocusing the interferometer due to wave packet displacements, while even order dispersion cancellation allows to measure time lags without losing resolution due to wave packet spreading. We report that either type of dispersion cancellation can be realized very easily in a triple Laue interferometer. Such interferometers are Mach–Zehnder interferometers based on Bragg diffraction, and are commonly used for neutrons and x-rays. Although the first x-ray interferometer was built nearly five decades ago, the feature of dispersion cancellation hasn't been recognized so far because the concept was hardly known in the neutron and x-ray community. However, it explains right away the surprising decoupling of phase shift and spatial displacement that we have discovered recently in neutron interferometry (Lemmel and Wagh 2010 Phys. Rev. A 82 033626). Furthermore, this article might inspire the light optics community to consider whether a triple Laue interferometer for laser light would be useful and feasible. We explain how dispersion cancellation works in neutron interferometry, and we describe the setup rigorously by solving the Schrödinger equation and by calculating the path integral. We point out, that the latter has to be evaluated with special care since in our setup the beam trajectory moves with respect to the crystal lattice of the interferometer. (paper)

  12. Generalized dispersive wave emission in nonlinear fiber optics.

    Science.gov (United States)

    Webb, K E; Xu, Y Q; Erkintalo, M; Murdoch, S G

    2013-01-15

    We show that the emission of dispersive waves in nonlinear fiber optics is not limited to soliton-like pulses propagating in the anomalous dispersion regime. We demonstrate, both numerically and experimentally, that pulses propagating in the normal dispersion regime can excite resonant dispersive radiation across the zero-dispersion wavelength into the anomalous regime.

  13. Land use and water pollution in Puerto Rico

    International Nuclear Information System (INIS)

    Arbona, S.I.

    1991-01-01

    In Puerto Rico, previous water-quality analyses have indicated that most surface-water bodies, as well as ground water, are polluted with both organic and inorganic substances. Contributions to water-quality deterioration come from point and nonpoint sources. These pose a threat on a densely populated island. Urban and industrial development occurred rapidly with a lag in the required infrastructure for expansion. Water pollution has been a by-product of this process and is regarded as the most serious environmental problem on the island. This study examines water-quality parameters in three hydrological basins. It attempts to determine how extensive a problem it is and how the concentration of pollutants compare in different land-use situations. A total of 33 sampling sites distributed among the three watersheds was chosen. Fifteen water-quality parameters were examined. All of the water bodies in spatial association with the land use considered presented detectable concentrations of the selected water-quality parameters

  14. Trailblazing the Carbon Cycle of Tropical Forests from Puerto Rico

    Directory of Open Access Journals (Sweden)

    Sandra Brown

    2017-03-01

    Full Text Available We review the literature that led to clarifying the role of tropical forests in the global carbon cycle from a time when they were considered sources of atmospheric carbon to the time when they were found to be atmospheric carbon sinks. This literature originates from work conducted by US Forest Service scientists in Puerto Rico and their collaborators. It involves the classification of forests by life zones, estimation of carbon density by forest type, assessing carbon storage changes with ecological succession and land use/land cover type, describing the details of the carbon cycle of forests at stand and landscape levels, assessing global land cover by forest type and the complexity of land use change in tropical regions, and assessing the ecological fluxes and storages that contribute to net carbon accumulation in tropical forests. We also review recent work that couples field inventory data, remote sensing technology such as LIDAR, and GIS analysis in order to more accurately determine the role of tropical forests in the global carbon cycle and point out new avenues of carbon research that address the responses of tropical forests to environmental change.

  15. EL ACONTECER HISTÓRICO EN EL RELATO DE VIDA

    Directory of Open Access Journals (Sweden)

    Patricia Pensado Leglise

    2014-12-01

    Full Text Available En este texto se analiza la metodología de la historia oral como lugar de convergencia entre prácticas diferentes de las Humanidades y las Ciencias Sociales, que se plantean como objetivo la comprensión de la realidad histórico social desde la experiencia del sujeto, mediante el testimonio oral. Se expone también la relación entre la historia social neomarxista y la historia oral, ambas interesadas en recuperar la historia de las clases dominadas. Se exponen también tres temas fundamentales: memoria, experiencia – expectativa e identidad local, así como la forma en que sus respectivos exponentes, José Carlos Sebe Bom Meihy -historiador brasileño-, Reinhardt Koselleck –historiador alemán- y Linda Shopes –historiadora urbana estadounidense- comprenden estas categorías. En la última parte, estas categorías se aplican en el análisis de fragmentos de 5 entrevistas que pertenecen a proyectos de investigación diferentes.

  16. Atitude do Consumidor: Estrutura dos Modelos Teóricos

    Directory of Open Access Journals (Sweden)

    Rafael Barreiros Porto

    2010-10-01

    Full Text Available Este trabalho visa oferecer uma organização de teorias de atitude originada por meio de levantamento bibliográfico da literatura de psicologia do consumidor. O pesquisador de marketing poderá ver algumas limitações e utilidades da medição do constructo - atitude - muitas vezes concebido através de pesquisas acadêmicas com o fim de compreender o processo de compra ou escolha. Pretendeu-se prover explicações sobre as estruturas formadoras de atitudes em modelos teóricos, ofertando uma classificação de ênfase de investigação empírica dos componentes da atitude. Este ensaio propõe uma agenda de pesquisa na área para que novas estratégias de investigação possam ser elaboradas em marketing.DOI: 10.5585/remark.v9i2.2145

  17. Alcohol concentration and risk of oral cancer in Puerto Rico.

    Science.gov (United States)

    Huang, Wen-Yi; Winn, Deborah M; Brown, Linda M; Gridley, Gloria; Bravo-Otero, Eleuterio; Diehl, Scott R; Fraumeni, Joseph F; Hayes, Richard B

    2003-05-15

    Alcohol consumption is a major risk factor for cancers of the mouth and pharynx (oral cancer), but the differential risks by beverage type are unclear. In this 1992-1995 study, the authors examined oral cancer risk in Puerto Rico, comparing alcohol intake among 286 male cases aged 21-79 years and 417 population-based male controls, frequency matched by age. Heavy consumers of liquor (>/=43 drinks per week) had strongly increased risks of oral cancer (odds ratio = 6.4, 95% confidence interval: 2.4, 16.8); beer/wine showed only modest effects. Among liquor drinkers, risks were consistently greater for those who drank straight (undiluted) liquor than for those who usually drank mixed (diluted) liquor (odds ratio = 4.0, 95% confidence interval: 2.4, 6.7). Risks associated with combined exposure to tobacco were also more pronounced when subjects drank liquor straight. The elevated risks associated with drinking homemade rum were similar to those for other types of liquor. These results suggest that alcohol concentration is a risk factor for oral cancer independent of the total quantity of alcohol consumed.

  18. Potentially hazardous plants of Puerto Rico: preliminary guide

    Energy Technology Data Exchange (ETDEWEB)

    Ferguson, F F; Medina, F R

    1975-08-01

    General information is presented about the kinds of native and imported plants in Puerto Rico (weeds, grasses, vines, cactuses, shrubs, trees and parts thereof) that should be avoided, or not ingested. Small amounts of eaten wild plant materials are usually not likely to be hazardous although large amounts may be dangerous; the striking exception is mushrooms. While a number of Puerto Rican plants are lethal to cattle, only a few are known to cause death to man as, for example, the fruit of the Deadly Manchineel, Hippomane mancinella and the seed of the Rosary Pea, Abrus precatorius. Tourists especially should avoid tasting any green or yellowish apples growing on a medium-sized tree. The Hippomane fruit resembles the Crabapple of temperate zones. It is now unlawful to use the Rosary Pea in the local handicraft industry. An item of special interest is the delicious fruit of Mamey often offered for sale at roadside, the outer coating of which is poisonous. All of the light brown outer covering, including especially all of the inner whitish tunic, must be carefully removed from the golden yellow fruit before eating, or else illness may result. Relatively few of the plants presented here will produce major physical problems if only contacted or chewed, but ingestion of some plant parts produces severe toxic symptoms.

  19. Los Cervantes de Américo Castro

    Directory of Open Access Journals (Sweden)

    Juan Goytisolo

    2007-12-01

    Full Text Available Al aceptar la invitación del Instituto Cervantes a participar en este coloquio sobre «El Quijote, taller de existencialidad» y, más concretamente, en el de «Cervantes y los casticismos españoles», a partir del análisis de la obra cervantina desde el prisma de Américo Castro, lo he hecho con cierta incomodidad, originada por la sensación de haber dicho ya lo que podía decir sobre el tema. En numerosos ensayos y artículos, he expuesto la aportación fundamental del autor de Cristianos, moros y judíos al conocimiento de la obra de nuestro primer escritor, fundador, con Rabelais, de la novela moderna, y me agobia la sensación de reiterarme. Como suelo decir a quienes me invitan a reuniones y conferencias del corte de las que les leo, los políticos y especialistas en homenajes y celebraciones pueden y deben repetirse, pero los escritores, no. Y lo que yo pueda decir de mi infinita deuda con Cervantes se expresa mejor en mis novelas que en charlas y mesas redondas.

  20. Anomalous dispersion enhanced Cerenkov phase-matching

    Energy Technology Data Exchange (ETDEWEB)

    Kowalczyk, T.C.; Singer, K.D. [Case Western Reserve Univ., Cleveland, OH (United States). Dept. of Physics; Cahill, P.A. [Sandia National Labs., Albuquerque, NM (United States)

    1993-11-01

    The authors report on a scheme for phase-matching second harmonic generation in polymer waveguides based on the use of anomalous dispersion to optimize Cerenkov phase matching. They have used the theoretical results of Hashizume et al. and Onda and Ito to design an optimum structure for phase-matched conversion. They have found that the use of anomalous dispersion in the design results in a 100-fold enhancement in the calculated conversion efficiency. This technique also overcomes the limitation of anomalous dispersion phase-matching which results from absorption at the second harmonic. Experiments are in progress to demonstrate these results.

  1. Noise figure of amplified dispersive Fourier transformation

    International Nuclear Information System (INIS)

    Goda, Keisuke; Jalali, Bahram

    2010-01-01

    Amplified dispersive Fourier transformation (ADFT) is a powerful tool for fast real-time spectroscopy as it overcomes the limitations of traditional optical spectrometers. ADFT maps the spectrum of an optical pulse into a temporal waveform using group-velocity dispersion and simultaneously amplifies it in the optical domain. It greatly simplifies spectroscopy by replacing the diffraction grating and detector array in the conventional spectrometer with a dispersive fiber and single-pixel photodetector, enabling ultrafast real-time spectroscopic measurements. Following our earlier work on the theory of ADFT, here we study the effect of noise on ADFT. We derive the noise figure of ADFT and discuss its dependence on various parameters.

  2. Phase noise of dispersion-managed solitons

    International Nuclear Information System (INIS)

    Spiller, Elaine T.; Biondini, Gino

    2009-01-01

    We quantify noise-induced phase deviations of dispersion-managed solitons (DMS) in optical fiber communications and femtosecond lasers. We first develop a perturbation theory for the dispersion-managed nonlinear Schroedinger equation (DMNLSE) in order to compute the noise-induced mean and variance of the soliton parameters. We then use the analytical results to guide importance-sampled Monte Carlo simulations of the noise-driven DMNLSE. Comparison of these results with those from the original unaveraged governing equations confirms the validity of the DMNLSE as a model for many dispersion-managed systems and quantify the increased robustness of DMS with respect to noise-induced phase jitter.

  3. An expert system for dispersion model interpretation

    International Nuclear Information System (INIS)

    Skyllingstad, E.D.; Ramsdell, J.V.

    1988-10-01

    A prototype expert system designed to diagnose dispersion model uncertainty is described in this paper with application to a puff transport model. The system obtains qualitative information from the model user and through an expert-derived knowledge base, performs a rating of the current simulation. These results can then be used in combination with dispersion model output for deciding appropriate evacuation measures. Ultimately, the goal of this work is to develop an expert system that may be operated accurately by an individual uneducated in meteorology or dispersion modeling. 5 refs., 3 figs

  4. 2007 IKONOS Image Vieques Puerto Rico - opo_244220_001_ps

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Benthic habitat maps of the nearshore marine environment of Vieques, Puerto Rico were created by visual interpretation of remotely sensed imagery. The objective of...

  5. 2007 IKONOS Image Vieques Puerto Rico - opo_244220_000_ps

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Benthic habitat maps of the nearshore marine environment of Vieques, Puerto Rico were created by visual interpretation of remotely sensed imagery. The objective of...

  6. Energy Transition Initiative: Island Energy Snapshot - Puerto Rico (Fact Sheet); NREL(National Renewable Energy Laboratory)

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-03-01

    This profile provides a snapshot of the energy landscape of the Commonwealth of Puerto Rico - a U.S. territory located about 60 miles east of the Dominican Republic and directly west of the U.S. Virgin Islands.

  7. Circulation Modeling for Proposed Port Facility at Ponce and Guayanilla, Puerto Rico

    National Research Council Canada - National Science Library

    Scheffner, Norman

    2002-01-01

    ... of Ponce and Guayanilla, Puerto Rico. Impacts of the proposed construction were determined by conducting numerical simulations of tidal and storm surge circulation at the project sites using with and without the proposed port facilities...

  8. Program Spotlight: Ground Broken for NCI-supported Cancer Treatment Center in Puerto Rico

    Science.gov (United States)

    Dr. Sanya A. Springfield represented NCI at the groundbreaking ceremonies for the University of Puerto Rico (UPR) cancer hospital. In her remarks, she acknowledged the driving force behind this development is the UPR and the MD Anderson Cancer Center partnership.

  9. Shallow-Water Benthic Habitats of Southwest Puerto Rico: Accuracy Assessment Site Locations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Shallow-water (<30m) benthic habitat maps of the nearshore marine environment of two areas in Southwest Puerto Rico (PR), including the Guanica Bay/La Parguera...

  10. Puerto Rico ESI/RSI: M_MAMMAL (Marine Mammal Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) and Reach Sensitivity Index (RSI) data for Puerto Rico. ESI data characterize estuarine...

  11. National Status and Trends: Bioeffects Program - Southwest Puerto Rico Chemical Contaminant Assessment Summary

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of the project was to characterize the extent and magnitude of chemical contamination in southwest Puerto Rico, as part of a larger effort to link coral...

  12. Northeast Puerto Rico and Culebra Island Principle Component Analysis - NOAA TIFF Image

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This GeoTiff is a representation of seafloor topography in Northeast Puerto Rico derived from a bathymetry model with a principle component analysis (PCA). The area...

  13. 40 CFR 131.42 - Antidegradation Implementation Methods for the Commonwealth of Puerto Rico.

    Science.gov (United States)

    2010-07-01

    ... Ambiental para el Proceso de Presentación, Evaluación y Trámite de Documentos Ambientales (EQB's... Procedimiento Administrativo Uniforme del Estado Libre Asociado de Puerto Rico (3 LPRA 2165). (d) Implementation...

  14. Northeast Puerto Rico and Culebra Island Bathymetry Model - NOAA TIFF Image

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This GeoTiff is a bathymetry model of the seafloor of Northeast Puerto Rico that contains the shallow water area (0-35m deep) of the Northeast Ecological Reserve:...

  15. Shallow-Water Benthic Habitats of Southwest Puerto Rico: Ground Validation Site Locations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Shallow-water (<30m) benthic habitat maps of the nearshore marine environment of two areas in Southwest Puerto Rico (PR), including the Guanica Bay/La Parguera...

  16. Shallow-Water Benthic Habitats of Southwest Puerto Rico: GeoEye Image po_502736_PS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Shallow-water (<30m) benthic habitat maps of the nearshore marine environment of two areas in Southwest Puerto Rico (PR), including the Guanica Bay/La Parguera...

  17. Soil As and Pb Levels and Plant Uptake in Three Gardens in Puerto Rico

    Data.gov (United States)

    U.S. Environmental Protection Agency — Total and bioaccessible arsenic and lead levels and plant uptake in garden plants from Puerto Rico. This dataset is not publicly accessible because: EPA cannot...

  18. Northeast Puerto Rico and Culebra Island World View 2 Satellite Mosaic - NOAA TIFF Image

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This GeoTiff is a mosaic of World View 2 panchromatic satellite imagery of Northeast Puerto Rico that contains the shallow water area (0-35m deep) surrounding...

  19. Precipitation Frequency for Puerto Rico and the US Virgin Islands - NOAA Atlas 14 Volume 3

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This GIS grid atlas contains precipitation frequency estimates for Puerto Rico and the U.S. Virgin Islands is based on precipitation data collected between...

  20. Shallow-Water Benthic Habitats of Southwest Puerto Rico: GeoEye Image po_483895_PS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Shallow-water (<30m) benthic habitat maps of the nearshore marine environment of two areas in Southwest Puerto Rico (PR), including the Guanica Bay/La Parguera...

  1. Chemical and physical analyses of selected plants and soils from Puerto Rico (1981-1990)

    Science.gov (United States)

    M. J. Sanchez; E. Lopez; A. E. Lugo

    1997-01-01

    This report contains the result of many analyses conducted at the laboratory of the IITF of Puerto Rico between 1981 and 1990. our objective was to make available the chemical and physical data developed for tropical forest ecosystems.

  2. Puerto Rico State Briefing Book for low-level radioactive waste management

    International Nuclear Information System (INIS)

    1981-10-01

    The Puerto Rico State Briefing Book is one of a series of state briefing books on low-level radioactive waste management practices. It has been prepared to assist state and federal agency officials in planning for safe low-level radioactive waste disposal. The report contains a profile of low-level radioactive waste generators in Puerto Rico. The profile is the result of a survey of NRC licensees in Puerto Rico. The briefing book also contains a comprehensive assessment of low-level radioactive waste management issues and concerns as defined by all major interested parties including industry, government, the media, and interest groups. The assessment was developed through personal communications with representatives of interested parties, and through a review of media sources. Lastly, the briefing book provides demographic and socioeconomic data and a discussion of relevant government agencies and activities, all of which may impact waste management practices in Puerto Rico

  3. Puerto Rico State Briefing Book for low-level radioactive waste management

    Energy Technology Data Exchange (ETDEWEB)

    1981-10-01

    The Puerto Rico State Briefing Book is one of a series of state briefing books on low-level radioactive waste management practices. It has been prepared to assist state and federal agency officials in planning for safe low-level radioactive waste disposal. The report contains a profile of low-level radioactive waste generators in Puerto Rico. The profile is the result of a survey of NRC licensees in Puerto Rico. The briefing book also contains a comprehensive assessment of low-level radioactive waste management issues and concerns as defined by all major interested parties including industry, government, the media, and interest groups. The assessment was developed through personal communications with representatives of interested parties, and through a review of media sources. Lastly, the briefing book provides demographic and socioeconomic data and a discussion of relevant government agencies and activities, all of which may impact waste management practices in Puerto Rico.

  4. 2006 IKONOS Image Vieques Puerto Rico - opo_215365_004_ps

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Benthic habitat maps of the nearshore marine environment of Vieques, Puerto Rico were created by visual interpretation of remotely sensed imagery. The objective of...

  5. 2006 IKONOS Image Vieques Puerto Rico - opo_215365_000_ps

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Benthic habitat maps of the nearshore marine environment of Vieques, Puerto Rico were created by visual interpretation of remotely sensed imagery. The objective of...

  6. 2006 IKONOS Image Vieques Puerto Rico - opo_215365_012_ps

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Benthic habitat maps of the nearshore marine environment of Vieques, Puerto Rico were created by visual interpretation of remotely sensed imagery. The objective of...

  7. 2008 IKONOS Image Vieques Puerto Rico - opo_255604_000_ps

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Benthic habitat maps of the nearshore marine environment of Vieques, Puerto Rico were created by visual interpretation of remotely sensed imagery. The objective of...

  8. Environmental Assessment for Authorizing the Puerto Rico Electric Power Authority (PREPA) to allow Public Access to the Boiling Nuclear Superheat (BONUS) Reactor Building, Rincon, Puerto Rico

    International Nuclear Information System (INIS)

    2003-01-01

    The U.S. Department of Energy (DOE) proposes to consent to a proposal by the Puerto Rico Electric Power Authority (PREPA) to allow public access to the Boiling Nuclear Superheat (BONUS) reactor building located near Rincon, Puerto Rico for use as a museum. PREPA, the owner of the BONUS facility, has determined that the historical significance of this facility, as one of only two reactors of this design ever constructed in the world, warrants preservation in a museum, and that this museum would provide economic benefits to the local community through increased tourism. Therefore, PREPA is proposing development of the BONUS facility as a museum

  9. Removal of Disperse Blue 56 and Disperse Red 135 dyes from aqueous dispersions by modified montmorillonite nanoclay

    Directory of Open Access Journals (Sweden)

    Ahmadishoar Javad

    2017-01-01

    Full Text Available In this study modified montmorillonite was used as an adsorbent for the removal of two selected disperse dyes i.e., Disperse Blue 56 (DB and Disperse Red 135 (DR from dye dispersions. The adsorption equilibrium data of dyes adsorption were investigated by using Nernst, Freundlich and Langmuir isotherm models. The adsorption kinetics was analyzed by using different models including pseudo-first-order, pseudo-second-order, Elovich and Intraparticle diffusion model. The Freundlich isotherm was found to be the most appropriate model for describing the sorption of the dyes on modified nanoclay. The best fit to the experimental results was obtained by using the pseudo-second-order kinetic equation, which satisfactorily described the process of dye adsorption. Although different kinetic models may control the rate of the adsorption process, the results indicated that the main rate limiting step was the intraparticle diffusion. The results showed that the proposed modified montmorillonite could be used as an effective adsorbent for the removal of disperse dyes even from highly concentrated dispersions.

  10. Luís de Camões - O Lírico

    Directory of Open Access Journals (Sweden)

    Sigismundo Spina

    1953-03-01

    Full Text Available CIDADE (Hernani. - Luís de Camões - O Lírico . Livraria Bertrand, Lisboa, 1952. 354 pp. (Primeiro Parágrafo do Artigo Os estudos da obra lírica de Camões levados a efeito pela erudição de Hernani Cidade datam de quase 20 anos, quando em 1936, na "Revista da Faculdade de Lisboa", escreveu "LUIS DE CAMÕES" - o Lírico.

  11. Diet of the non-native spectacled caiman (Caiman crocodilus) in Puerto Rico

    Science.gov (United States)

    Damien Bontemps; Elvira Cuevas; Eileen Ortiz; Joseph Wunderle Jr.; Rafael Joglar

    2016-01-01

    The spectacled caiman (Caiman crocodilus) was introduced to Puerto Rico over 50 years ago with the Tortuguero Lagoon Natural Reserve (TLNR) as its epicenter, where it is now established as an apex predator. Although concerns have been raised regarding the potential impact of this naturalized predator on Puerto Rico’s native fauna, little was known of the caiman’s diet...

  12. La erradicación de la malaria en Puerto Rico

    Directory of Open Access Journals (Sweden)

    Miranda Franco Rafael

    1997-01-01

    Full Text Available For decades, malaria was a serious public health problem in Puerto Rico. In 1962, that country became the first tropical territory in the Americas, and possibly in the world, to receive certification from WHO for having eradicated malaria and having declared itself free of the disease. This report chronicles the tremendous effort that was dedicated to the eradication campaign in Puerto Rico, which took place in the first part of this century.

  13. Medicamentos genéricos y de marca-Calidad e intercambiabilidad

    Directory of Open Access Journals (Sweden)

    Rua F.

    2012-03-01

    Full Text Available El interés por los medicamentos genéricos procede de la necesidad de los sistemas sanitarios de reducir la factura sanitaria sin merma de los objetivos de salud. Su expansión y uso requieren la aceptación de la población y de los profesionales. También requieren que se despejen algunas dudas sobre su verdadera equivalencia respecto a los medicamentos originales. Desde su introducción en el mercado farmacéutico existe el debate de si son correctamente investigados y de alta calidad. No son infrecuentes los conceptos equivocados entre los profesionales sobre los genéricos, en especial, el supuesto hecho de que pueden llegar a contener hasta un 20% menos de concentración en principio activo. Estas creencias erróneas sugieren una situación de desventaja en la eficacia y la tolerabilidad de los medicamentos genéricos comparados con sus equivalentes de marca, disminuyendo la credibilidad de los mismos. Así, en una encuesta realizada en 2008 los farmacéuticos opinaron que los genéricos y las marcas son diferentes en eficacia (26%, equivalencia (28% y, sobre todo, en la calidad del excipiente (46%, aumentando la percepción de que los genéricos son diferentes en función del laboratorio que los fabrica (52,8%. En este artículo, con el fin de ampliar los conocimientos sobre medicamentos genéricos, solucionar dudas y proporcionar información, objetiva, clara y rigurosa, se revisan los posibles prejuicios sobre genéricos y se exponen las evidencias que existen en torno a los mismos, como los requisitos de bioequivalencia de los productos genéricos, analizando si ésta corrobora adecuadamente la equivalencia terapéutica y de intercambio.

  14. Attitudes toward business creation: A comparative study between Catalonia and Puerto Rico

    Directory of Open Access Journals (Sweden)

    Marinés Aponte

    2006-10-01

    Full Text Available In this research the attitudes towards entrepreneurship of two samples of university students from Catalonia and Puerto Rico are analysed. Perceptions of desirability, feasibility and the intention to start a new firm are studied and compared. Institutional Economic Theory is used as a theoretical framework of the research due to its adequacy to the analysis of the conditioning factors to entrepreneurship. Not relevant differences in the attitudes to entrepreneurship between Catalonia and Puerto Rico are found in the research.

  15. New distribution record of Cybocephalus kathrynae (Coleoptera, Cybocephalidae on Mona Island, Puerto Rico

    Directory of Open Access Journals (Sweden)

    Jean Carlos Curbelo-Rodríguez

    2012-03-01

    Full Text Available New distribution record of Cybocephalus Kathrynae (Coleoptera, Cybocephalidae on Mona Island, Puerto Rico. A new record of Cybocephalus kathrynae T.R. Smith (Cybocephalidae is reported for Puerto Rico. Adults were collected from the flowers of Mammillaria nivosa (Cactaceae on Mona Island Reserve. Prior to this study, this beetle species was only reported for Monroe and Miami-Dade Counties, Florida, USA.

  16. Dispersion, sorption and photodegradation of petroleum hydrocarbons in dispersant-seawater-sediment systems.

    Science.gov (United States)

    Zhao, Xiao; Liu, Wen; Fu, Jie; Cai, Zhengqing; O'Reilly, S E; Zhao, Dongye

    2016-08-15

    This work examined effects of model oil dispersants on dispersion, sorption and photodegradation of petroleum hydrocarbons in simulated marine systems. Three dispersants (Corexit 9500A, Corexit 9527A and SPC 1000) were used to prepare dispersed water accommodated oil (DWAO). While higher doses of dispersants dispersed more n-alkanes and PAHs, Corexit 9500A preferentially dispersed C11-C20 n-alkanes, whereas Corexit 9527A was more favorable for smaller alkanes (C10-C16), and SPC 1000 for C12-C28 n-alkanes. Sorption of petroleum hydrocarbons on sediment was proportional to TPH types/fractions in the DWAOs. Addition of 18mg/L of Corexit 9500A increased sediment uptake of 2-3 ring PAHs, while higher dispersant doses reduced the uptake, due to micelle-enhanced solubilization effects. Both dispersed n-alkanes and PAHs were susceptible to photodegradation under simulated sunlight. For PAHs, both photodegradation and photo-facilitated alkylation were concurrently taking place. The information can facilitate sounder assessment of fate and distribution of dispersed oil hydrocarbons in marine systems. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Effects of chemical dispersants on oil physical properties and dispersion. Volume 1

    International Nuclear Information System (INIS)

    Khelifa, A.; Fingas, M.; Hollebone, B.P.; Brown, C.E.; Pjontek, D.

    2007-01-01

    Laboratory and field testing have shown that the dispersion of oil spilled in water is influenced by chemical dispersants via the modification of the interfacial properties of the oil, such as oil-brine interfacial tension (IFT). This study focused on new laboratory experiments that measured the effects on the physical properties and dispersion of oil, with particular reference to the effects of chemical dispersants on IFT and oil viscosity and the subsequent effects on oil droplet formation. Experiments were conducted at 15 degrees C using Arabian Medium, Alaska North Slope and South Louisiana crude and Corexit 9500 and Corexit 9527 chemical dispersants. The dispersants were denser than the 3 oils. The effect of IFT reduction on oil dispersion was measured and showed substantial reduction in the size and enhancement of the concentration of oil droplets in the water column. It was shown that the brine-oil IFT associated with the 3 crudes reduced to less than 3.6 mN/m with the application of the chemical dispersants, even at a low dispersant-to-oil ratio (DOR) value of 1:200. The use of chemical dispersants increased the viscosity of the dispersant-oil mixture up to 40 per cent over the neat crude oil. It was shown that for each mixing condition, an optimum value of DOR exists that provides for maximal dispersant effectiveness. The IFT reaches maximum reduction at optimum DOR. It was suggested that oil spill modelling can be improved with further study of IFT reduction with DOR and variations of critical micelle concentration with the type and solubility of chemical dispersant, oil type and oil to water ratio. 13 refs., 3 tabs., 7 figs

  18. Dispersal Timing: Emigration of Insects Living in Patchy Environments.

    Directory of Open Access Journals (Sweden)

    Milica Lakovic

    Full Text Available Dispersal is a life-history trait affecting dynamics and persistence of populations; it evolves under various known selective pressures. Theoretical studies on dispersal typically assume 'natal dispersal', where individuals emigrate right after birth. But emigration may also occur during a later moment within a reproductive season ('breeding dispersal'. For example, some female butterflies first deposit eggs in their natal patch before migrating to other site(s to continue egg-laying there. How breeding compared to natal dispersal influences the evolution of dispersal has not been explored. To close this gap we used an individual-based simulation approach to analyze (i the evolution of timing of breeding dispersal in annual organisms, (ii its influence on dispersal (compared to natal dispersal. Furthermore, we tested (iii its performance in direct evolutionary contest with individuals following a natal dispersal strategy. Our results show that evolution should typically result in lower dispersal under breeding dispersal, especially when costs of dispersal are low and population size is small. By distributing offspring evenly across two patches, breeding dispersal allows reducing direct sibling competition in the next generation whereas natal dispersal can only reduce trans-generational kin competition by producing highly dispersive offspring in each generation. The added benefit of breeding dispersal is most prominent in patches with small population sizes. Finally, the evolutionary contests show that a breeding dispersal strategy would universally out-compete natal dispersal.

  19. Psicologia e acupuntura: aspectos históricos, políticos e teóricos

    Directory of Open Access Journals (Sweden)

    Delvo Ferraz da Silva

    Full Text Available Este artigo apresenta a evolução histórica, política e teórica da acupuntura em nossa sociedade. Explora o modelo teórico proposto pela Medicina tradicional chinesa, que tem como base o conhecimento adquirido através de observações sistemáticas que ocorreram em milhares de anos e que, quando aceitos como verdades por todos os observadores, são integrados ao conjunto de conhecimentos que os orientais chamam de As Tradições. Esses conhecimentos são transmitidos de geração a geração, até o presente. Com a aproximação entre as ciências ocidentais e as tradições orientais, resultado dos esforços das Nações Unidas que culminou com a declaração de Veneza, em 1986, buscou-se apresentar, neste trabalho, como essas tradições percebem o ser humano, em particular, a psique.

  20. The Dangers of Dispersal of Responsibilities

    Directory of Open Access Journals (Sweden)

    Adriana Schiopoiu Burlea

    2017-05-01

    Full Text Available Taking into account that it is in the nature of the modern corporation that risks are distributed over several agents, we discuss in this paper the organisational behaviour as it results from such dispersal of responsibilities for both the principal and the agent. We explore the hypothesis that dispersal of responsibilities could be the result or a cause of a lack of consensus between the principal and the agent. Our findings suggest that a dispersal of responsibilities has a negative impact on the principal-agent relationship and that it represents a foundation for theoretical and empirical approaches to organisational behaviour. We find that agent perceptions of a dispersal of responsibilities are linked to his/her resistance to the principal’s interests, but this relationship is deeper than was suggested by previous research. However, if the sharing of responsibilities does not run parallel to that, we may have as a result what we call an agency problem.

  1. Adsorption of an anionic dispersant on lignite

    Energy Technology Data Exchange (ETDEWEB)

    Yavuz, R.; Kucukbayrak, S. [Istanbul Technical University, Istanbul (Turkey). Dept. of Chemical Engineering, Chemical & Metallurgical Engineering Faculty

    2001-12-01

    Since coal is not a homogeneous substance but a mixture of carbonaceous materials and mineral matter, it has a variety of surface properties. Therefore, it is not easy to control the properties of coal suspensions by simply adjusting variables, such as pH and/or electrolyte. A chemical agent needs to be added to control the properties of the coal suspensions. The adsorption behavior of an anionic dispersant in the presence of a wetting agent using some Turkish lignite samples was investigated. The effects of dispersant concentration, temperature and pH on the dispersant adsorption were studied systematically, and the experimental results are presented. Pellupur B69 as a dispersant, commercial mixture of formaldehyde condensate sodium salt of naphthalene sulphonic acid, and Texapon N{sub 2}5 as a wetting agent, a sodium lauryl ether sulfate, have been used.

  2. Dispersion engineering in metamaterials and metasurfaces

    Science.gov (United States)

    Li, Xiong; Pu, Mingbo; Ma, Xiaoliang; Guo, Yinghui; Gao, Ping; Luo, Xiangang

    2018-02-01

    Dispersion engineering is essential for spectral utilization in electromagnetic systems. However, it is difficult to manage the dispersions in both natural materials and traditional electromagnetic waveguides since they are tightly related to fine structures of atoms, molecules and causality. The emergence of metamaterials and metasurfaces, which are made of subwavelength inclusions offers tremendous freedom to manipulate the electromagnetic parameters of materials and modes. Here, we review the basic principles, practical applications and recent advancements of the dispersion engineering in metadevices. The contributions of dispersion management in metadevice-based super-resolution imaging/nanolithography systems, planar functional devices, as well as the broadband perfect absorbers/polarization converters are discussed in depth. The challenges faced by this field as well as future developing trends are also presented in the conclusions.

  3. PETROLEUM-COLLECTING AND DISPERSING CHEMICALS FOR ...

    African Journals Online (AJOL)

    Preferred Customer

    Films of petroleum origin reflecting sunlight rays hinder absorption of energy by water necessary for life ... Dispersing chemicals like mechanical clean-up methods have their own place in fighting oil spills. They are ... yellow color, and filtered.

  4. Resuspension parameters for TRAC dispersion model

    International Nuclear Information System (INIS)

    Langer, G.

    1987-01-01

    Resuspension factors for the wind erosion of soil contaminated with plutonium are necessary to run the Rocky Flats Plant Terrain Responsive Atmospheric Code (TRAC). The model predicts the dispersion and resulting population dose due to accidental plutonium releases

  5. Modeling electrical dispersion phenomena in Earth materials

    Directory of Open Access Journals (Sweden)

    D. Patella

    2008-06-01

    Full Text Available It is illustrated that IP phenomena in rocks can be described using conductivity dispersion models deduced as solutions to a 2nd-order linear differential equation describing the motion of a charged particle immersed in an external electrical field. Five dispersion laws are discussed, namely: the non-resonant positive IP model, which leads to the classical Debye-type dispersion law and by extension to the Cole-Cole model, largely used in current practice; the non-resonant negative IP model, which allows negative chargeability values, known in metals at high frequencies, to be explained as an intrinsic physical property of earth materials in specific field cases; the resonant flat, positive or negative IP models, which can explain the presence of peak effects at specific frequencies superimposed on flat, positive or negative dispersion spectra.

  6. Long anterior zonules and pigment dispersion.

    Science.gov (United States)

    Moroi, Sayoko E; Lark, Kurt K; Sieving, Paul A; Nouri-Mahdavi, Kouros; Schlötzer-Schrehardt, Ursula; Katz, Gregory J; Ritch, Robert

    2003-12-01

    To describe pigment dispersion associated with long anterior zonules. Multicenter observational case series. Fifteen patients, seven of whom were treated for glaucoma or ocular hypertension, were identified with long anterior zonules and pigment dispersion. Transmission electron microscopy was performed on one anterior capsule specimen. All patients had anterior zonules that inserted centrally on the lens capsule. Signs of pigment dispersion included corneal endothelial pigmentation, loss of the pupillary ruff, and variable trabecular meshwork pigmentation. Ultrasound biomicroscopy verified the lack of posterior iris insertion and concavity. There was no exfoliation material. Transmission electron microscopy showed zonular lamellae with adherent pigment granules, and no exfoliation material. Long anterior zonules inserted onto the central lens capsule may cause mechanical disruption of the pigment epithelium at the pupillary ruff and central iris leading to pigment dispersion.

  7. Analytic properties of the whistler dispersion function

    International Nuclear Information System (INIS)

    Daniell, G.J.

    1986-01-01

    The analytic properties of the dispersion function of a whistler are investigated in the complex frequency plane. It possesses a pole and a branch point at a frequency equal to the minimum value of the electron gyrofrequency along the path of propagation. An integral equation relates the dispersion function to the distribution of magnetospheric electrons along the path and the solution of this equation is obtained. It is found that the electron density in the equatorial plane is very simply related to the dispersion function. A discussion of approximate formulae to represent the dispersion shows how particular terms can be related to attributes of the electron density distribution, and a new approximate formula is proposed. (author)

  8. SANS observations on weakly flocculated dispersions

    DEFF Research Database (Denmark)

    Mischenko, N.; Ourieva, G.; Mortensen, K.

    1997-01-01

    Structural changes occurring in colloidal dispersions of poly-(methyl metacrylate) (PMMA) particles, sterically stabilized with poly-(12-hydroxystearic acid) (PHSA), while varying the solvent quality, temperature and shear rate, are investigated by small-angle neutron scattering (SANS......). For a moderately concentrated dispersion in a marginal solvent the transition on cooling from the effective stability to a weak attraction is monitored, The degree of attraction is determined in the framework of the sticky spheres model (SSM), SANS and rheological results are correlated....

  9. Phonon dispersion relations for caesium thiocyanate

    International Nuclear Information System (INIS)

    Irving, M.A.; Smith, T.F.; Elcombe, M.M.

    1984-01-01

    Room temperature phonon dispersion relations for frequencies below 2 THz have been measured, along the three orthorhombic axes and selected diagonal directions by neutron inelastic scattering, for caesium thiocyanate. These curves, which represent 13 acoustic modes and 11 optic modes of vibration, do not agree with the dispersion behaviour calculated from the rigid-ion model developed by Ti and Ra to describe their Raman scattering observations

  10. Modelling of pollution dispersion in atmosphere

    International Nuclear Information System (INIS)

    Borysiewicz, M.; Stankiewicz, R.

    1994-01-01

    The paper contains the review of the mathematical foundation of atmospheric dispersion models. The atmospheric phenomena relevant to atmospheric dispersion model are discussed. In particular the parametrization of processes with time and space scales smaller than numerical grid size, limited by available computer power, is presented. The special attention was devoted to similarity theory and parametrization of boundary layer. The numerical methods are analysed and the drawbacks of the method are presented. (author). 99 refs, 15 figs, 3 tabs

  11. Employment Effects of Spatial Dispersal of Refugees

    DEFF Research Database (Denmark)

    Damm, Anna Piil; Rosholm, Michael

    Spatial dispersal policies may influence labour market integration of refugees through two mechanisms. First, it may affect the local job offer arrival rate, and second, it may affect place utility. We investigate the second mechanism theoretically by formulating a partial search model in which a...... due to large local reservation wage effects. We investigate both mechanisms empirically and test the predictions of the theoretical model by evaluating the employment effects of the Danish spatial dispersal policy carried out 1986-1998....

  12. Employment Effects of Spatial Dispersal of Refugees

    OpenAIRE

    Damm, Anna Piil; Rosholm, Michael

    2005-01-01

    We argue that spatial dispersal influences labour market assimilation of refugees through two mechanisms: first, the local job offer arrival rate and, second, place utility. Our partial search model with simultaneous job and residential location search predicts that the reservation wage for local jobs decreases with place utility. We argue that spatial dispersal decreases average place utility of refugees which decreases the transition rate into first job due to large local reservation wages....

  13. URANIUM BISMUTHIDE DISPERSION IN MOLTEN METAL

    Science.gov (United States)

    Teitel, R.J.

    1959-10-27

    The formation of intermetallic bismuth compounds of thorium or uranium dispersed in a liquid media containing bismuth and lead is described. A bismuthide of uranium dispersed in a liquid metal medium is formed by dissolving uranium in composition of lead and bismuth containing less than 80% lead and lowering the temperature of the composition to a temperature below the point at which the solubility of uranium is exceeded and above the melting point of the composition.

  14. Dispersed-phase catalysis in coal liquefaction

    International Nuclear Information System (INIS)

    Utz, B.R.; Cugini, A.V.; Frommell, E.A.

    1990-01-01

    This paper reports that the specific reaction (activation) conditions for the conversion of catalyst precursors to unsupported catalyst have a direct effect on the catalytic activity and dispersion. The importance of reaction intermediates in decomposition of ammonium heptamolybdate and ammonium tetrathiomolybdate, and the sensitivity of these intermediates to reaction conditions, were studied in coal liquefaction systems. Recent results indicate that optimization of activation conditions facilitates the formation of a highly dispersed and active form of molybdenum disulfide for coal liquefaction. The use of the catalyst precursors ammonium heptamolybdate, ammonium tetrathiomolybdate, and molybdenum trisulfide for the conversion of coal to soluble products will be discussed. The use of an unsupported dispersed-phase catalyst for direct coal liquefaction is not a novel concept and has been employed in may studies with varying success. Dispersed-phase catalysts soluble and oil-soluble salts, and as finely divided powders. While some methods of catalyst introduction give higher dispersion of the catalyst and greater activity for the liquefaction of coal, all of the techniques allow the formation of a finely dispersed inorganic phase

  15. Estimate of dispersion in an unsaturated aquifer

    Science.gov (United States)

    Stephenson, D.; De Jesus, A. S. M.

    1985-10-01

    The Nuclear Development Corporation of South Africa (Pty) Ltd. (NUCOR) is constructing a low-level radioactive waste disposal site near Springbok in Namaqualand, an arid region to the west of South Africa. A groundwater model was developed which required site-specific data and this work describes procedures developed to assess the dispersivity of the soil in the vicinity of the proposed site. Preliminary laboratory tests, carried out using a sodium chloride solution, indicated the order of magnitude of the dispersivity for saturated soil at various levels. This enabled site tests to be designed. The site tests were done by injecting a pulse of scandium-46 into a hole and monitoring the displacement of the radioactive cloud as it moved down under gravity and spread laterally. A mathematical model was developed to predict the behaviour of the cloud and calibration of the model yielded vertical and horizontal dispersivities. The dispersion of radioactivity at the cloud front was assumed to occur in unsaturated medium while the continuously injected water behind the radioactivity was assumed to disperse in a saturated medium. Thus monitoring the concentration of both yielded approximate values for the effective dispersivities in unsaturated and saturated media.

  16. Spatially varying dispersion to model breakthrough curves.

    Science.gov (United States)

    Li, Guangquan

    2011-01-01

    Often the water flowing in a karst conduit is a combination of contaminated water entering at a sinkhole and cleaner water released from the limestone matrix. Transport processes in the conduit are controlled by advection, mixing (dilution and dispersion), and retention-release. In this article, a karst transport model considering advection, spatially varying dispersion, and dilution (from matrix seepage) is developed. Two approximate Green's functions are obtained using transformation of variables, respectively, for the initial-value problem and for the boundary-value problem. A numerical example illustrates that mixing associated with strong spatially varying conduit dispersion can cause strong skewness and long tailing in spring breakthrough curves. Comparison of the predicted breakthrough curve against that measured from a dye-tracing experiment between Ames Sink and Indian Spring, Northwest Florida, shows that the conduit dispersivity can be as large as 400 m. Such a large number is believed to imply strong solute interaction between the conduit and the matrix and/or multiple flow paths in a conduit network. It is concluded that Taylor dispersion is not dominant in transport in a karst conduit, and the complicated retention-release process between mobile- and immobile waters may be described by strong spatially varying conduit dispersion. Copyright © 2010 The Author(s). Journal compilation © 2010 National Ground Water Association.

  17. Juvenile dispersal in Calomys venustus (Muridae: Sigmodontinae)

    Science.gov (United States)

    Priotto, José; Steinmann, Andrea; Provensal, Cecilia; Polop, Jaime

    2004-05-01

    Both spacing behaviour and dispersal movement are viewed as hierarchical processes in which the effects may be expressed at spatial scale. This research was carried out to examine the hypothesis that the presence of parents promotes the dispersal of juveniles from their natal nest and their father or mother home-range, in Calomys venustus.The study was carried out in four 0.25 ha fences (two controls and two experimentals), in a natural pasture. This study had two periods: Father Removal (FR) (August and December 1997; year one) and Mother Removal (MR) (August 1998 and January 1999; year two). For the FR treatment fathers were removed after juveniles were born, but in the MR treatment mothers were removed after the juveniles were weaned. The effect of parents on the dispersal distance of juveniles was analysed with respect to their natal nest and their mother and father home-range. Dispersal distance from the nest of C. venustus was independent of either male or female parent. Juveniles were more dispersing in relation to the centre of activity of their mothers than to that of their fathers, and females were more dispersing than males. Female juveniles overlap their home-range with their parents less than male juveniles do. The differences observed between female and male juveniles would be related to their different sexual maturation times, as well as to the female territoriality.

  18. Magnon dispersion in thin magnetic films

    International Nuclear Information System (INIS)

    Balashov, T; Wulfhekel, W; Buczek, P; Sandratskii, L; Ernst, A

    2014-01-01

    Although the dispersion of magnons has been measured in many bulk materials, few studies deal with the changes in the dispersion when the material is in the form of a thin film, a system that is of interest for applications. Here we review inelastic tunneling spectroscopy studies of magnon dispersion in Mn/Cu 3 Au(1 0 0) and present new studies on Co and Ni thin films on Cu(1 0 0). The dispersion in Mn and Co films closely follows the dispersion of bulk samples with negligible dependence on thickness. The lifetime of magnons depends slightly on film thickness, and decreases considerably as the magnon energy increases. In Ni/Cu(1 0 0) films the thickness dependence of dispersion is much more pronounced. The measurements indicate a considerable mode softening for thinner films. Magnon lifetimes decrease dramatically near the edge of the Brillouin zone due to a close proximity of the Stoner continuum. The experimental study is supported by first-principles calculations. (paper)

  19. Magnon dispersion in thin magnetic films.

    Science.gov (United States)

    Balashov, T; Buczek, P; Sandratskii, L; Ernst, A; Wulfhekel, W

    2014-10-01

    Although the dispersion of magnons has been measured in many bulk materials, few studies deal with the changes in the dispersion when the material is in the form of a thin film, a system that is of interest for applications. Here we review inelastic tunneling spectroscopy studies of magnon dispersion in Mn/Cu3Au(1 0 0) and present new studies on Co and Ni thin films on Cu(1 0 0). The dispersion in Mn and Co films closely follows the dispersion of bulk samples with negligible dependence on thickness. The lifetime of magnons depends slightly on film thickness, and decreases considerably as the magnon energy increases. In Ni/Cu(1 0 0) films the thickness dependence of dispersion is much more pronounced. The measurements indicate a considerable mode softening for thinner films. Magnon lifetimes decrease dramatically near the edge of the Brillouin zone due to a close proximity of the Stoner continuum. The experimental study is supported by first-principles calculations.

  20. Surgical Management of Iatrogenic Pigment Dispersion Glaucoma.

    Science.gov (United States)

    Mierlo, Camille Van; Pinto, Luis Abegão; Stalmans, Ingeborg

    2015-01-01

    Iatrogenic pigment dispersion syndrome generally originates from a repetitive, mechanical trauma to the pigmented posterior epithelium of the iris. This trauma can arise after intraocular surgery, most commonly due to an abnormal contact between the intraocular lens (IOL) and the iris. Whether surgical removal of this primary insult can lead to a successful intraocular pressure (IOP) control remains unclear. Case-series. Patients with IOP elevation and clinical signs of pigment dispersion were screened for a diagnosis of iatrogenic IOL-related pigment dispersion. Three patients in which the IOL or the IOL-bag complex caused a pigment dispersion through a repetitive iris chafing were selected. In two cases, replacement of a sulcus-based single-piece IOL (patient 1) or a sub-luxated in-the-bag IOL (patient 2) by an anterior-chamber (AC) iris-fixed IOL led to a sustained decrease in IOP. In the third case, extensive iris atrophy and poor anatomical AC parameters for IOL implantation precluded further surgical intervention. IOL-exchange appears to be a useful tool in the management of iatrogenic pigment dispersion glaucoma due to inappropriate IOL implantation. This cause-oriented approach seems to be effective in controlling IOP, but should be offered only if safety criteria are met. How to cite this article: Van Mierlo C, Abegao Pinto L, Stalmans I. Surgical Management of Iatrogenic Pigment Dispersion Glaucoma. J Curr Glaucoma Pract 2015;9(1):28-32.