WorldWideScience

Sample records for juvenile migration timing

  1. Body size and condition influence migration timing of juvenile Arctic grayling

    Science.gov (United States)

    Heim, Kurt C.; Wipfli, Mark S.; Whitman, Matthew S.; Seitz, Andrew C.

    2016-01-01

    Freshwater fishes utilising seasonally available habitats within annual migratory circuits time movements out of such habitats with changing hydrology, although individual attributes of fish may also mediate the behavioural response to environmental conditions. We tagged juvenile Arctic grayling in a seasonally flowing stream on the Arctic Coastal Plain in Alaska and recorded migration timing towards overwintering habitat. We examined the relationship between individual migration date, and fork length (FL) and body condition index (BCI) for fish tagged in June, July and August in three separate models. Larger fish migrated earlier; however, only the August model suggested a significant relationship with BCI. In this model, 42% of variability in migration timing was explained by FL and BCI, and fish in better condition were predicted to migrate earlier than those in poor condition. Here, the majority (33%) of variability was captured by FL with an additional 9% attributable to BCI. We also noted strong seasonal trends in BCI reflecting overwinter mass loss and subsequent growth within the study area. These results are interpreted in the context of size and energetic state-specific risks of overwinter starvation and mortality (which can be very high in the Arctic), which may influence individuals at greater risk to extend summer foraging in a risky, yet prey rich, habitat. Our research provides further evidence that heterogeneity among individuals within a population can influence migratory behaviour and identifies potential risks to late season migrants in Arctic beaded stream habitats influenced by climate change and petroleum development.

  2. Effect of Migration Pathway on Travel Time and Survival of Acoustic-Tagged Juvenile Salmonids in the Columbia River Estuary

    Energy Technology Data Exchange (ETDEWEB)

    Harnish, Ryan A.; Johnson, Gary E.; McMichael, Geoffrey A.; Hughes, Michael S.; Ebberts, Blaine D.

    2012-02-01

    Off-channel areas (side channels, tidal flats, sand bars, and shallow-water bays) may serve as important migration corridors through estuarine environments for salmon and steelhead smolts. Relatively large percentages (21-33%) of acoustic-tagged yearling and subyearling Chinook salmon and steelhead smolts were detected migrating through off-channel areas of the Columbia River estuary in 2008. The probability of survival for off-channel migrants (0.78-0.94) was similar to or greater than the survival probability of main channel migrants (0.67-0.93). Median travel times were similar for all species or run types and migration pathways we examined, ranging from 1-2 d. The route used by smolts to migrate through the estuary may affect their vulnerability to predation. Acoustic-tagged steelhead that migrated nearest to avian predator nesting colonies experienced higher predation rates (24%) than those that migrated farthest from the colonies (10%). The use of multiple migration pathways may be advantageous to out-migrating smolts because it helps to buffer against high rates of mortality, which may occur in localized areas, and helps to minimize inter- and intraspecific competition.

  3. Tracking from the tropics reveals behaviour of juvenile songbirds on their first spring migration.

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    Emily A McKinnon

    Full Text Available Juvenile songbirds on spring migration travel from tropical wintering sites to temperate breeding destinations thousands of kilometres away with no prior experience to guide them. We provide a first glimpse at the migration timing, routes, and stopover behaviour of juvenile wood thrushes (Hylocichla mustelina on their inaugural spring migration by using miniaturized archival geolocators to track them from Central America to the U.S. and Canada. We found significant differences between the timing of juvenile migration and that of more experienced adults: juveniles not only departed later from tropical wintering sites relative to adults, they also became progressively later as they moved northward. The increasing delay was driven by more frequent short stops by juveniles along their migration route, particularly in the U.S. as they got closer to breeding sites. Surprisingly, juveniles were just as likely as adults to cross the Gulf of Mexico, an open-water crossing of 800-1000 km, and migration route at the Gulf was not significantly different for juveniles relative to adults. To determine if the later departure of juveniles was related to poor body condition in winter relative to adults, we examined percent lean body mass, fat scores, and pectoral muscle scores of juvenile versus adult birds at a wintering site in Belize. We found no age-related differences in body condition. Later migration timing of juveniles relative to adults could be an adaptive strategy (as opposed to condition-dependent to avoid the high costs of fast migration and competition for breeding territories with experienced and larger adults. We did find significant differences in wing size between adults and juveniles, which could contribute to lower flight efficiency of juveniles and thus slower overall migration speed. We provide the first step toward understanding the "black box" of juvenile songbird migration by documenting their migration timing and en route performance.

  4. Results of domestic migration on juvenile delinquency in Adana, Turkey.

    Science.gov (United States)

    Firat, Sunay; Iltas, Yigit; Gulmen, Mete K

    2017-07-01

    The aim of this study is to determine the effect of migration on children in the juvenile justice system. The study takes into account whether these children arrived in the city via migration or not, the types of crimes against property and persons committed by the children brought before the Juvenile Courts, and the types, frequency, and durations of punishments and precautionary decisions they received. In addition, the study examines the children's ability to realize the meaning and consequences of their crimes and to lead their future behaviors effectively. Data gathered from children between 3 and 18 years of age who appeared before the 1, 2, and 3 numbered Juvenile Courts of Adana Courthouse after January 2004 on charges of committing a crime, and/or children who were sent to or who applied to the Provincial Directorate for National Education based on the decision of the Court has been evaluated retrospectively. Six hundred and eighty children were studied. Of these, 602 (88.5%) were male and 78 (11.5) were female. The average age of the child at the time of the commitment of the crime was 13 years and 8 months ± 2.18 years. It has been observed that there are statistically meaningful differences for children involved in delinquency between cases whether they come via migration or regardless of migration and types of crimes committed (p = 0.004). When cities faced with migration from other places and types of crime committed by children are compared, it has been observed that there are meaningful differences between the types of crimes committed by non-migrant versus migrant children (p = 0.012). It is important to state the reasons for delinquency and to obtain data to prevent future delinquency and to put forward regional and local recommendations within the scope of the data. Copyright © 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  5. 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.

  6. Synthesis of juvenile lamprey migration and passage research and monitoring at Columbia and Snake River Dams

    Science.gov (United States)

    Mesa, Matthew G.; Weiland, Lisa K.; Christiansen, Helena E.

    2016-01-01

    We compiled and summarized previous sources of data and research results related to the presence, numbers, and migration timing characteristics of juvenile (eyed macropthalmia) and larval (ammocoetes) Pacific lamprey Entosphenus tridentatus, in the Columbia River basin (CRB). Included were data from various screw trap collections, data from historic fyke net studies, catch records of lampreys at JBS facilities, turbine cooling water strainer collections, and information on the occurrence of lampreys in the diets of avian and piscine predators. We identified key data gaps and uncertainties that should be addressed in a juvenile lamprey passage research program. The goal of this work was to summarize information from disparate sources so that managers can use it to prioritize and guide future research and monitoring efforts related to the downstream migration of juvenile Pacific lamprey within the CRB. A common finding in all datasets was the high level of variation observed for CRB lamprey in numbers present, timing and spatial distribution. This will make developing monitoring programs to accurately characterize lamprey migrations and passage more challenging. Primary data gaps centered around our uncertainty on the numbers of juvenile and larval present in the system which affects the ability to assign risk to passage conditions and prioritize management actions. Recommendations include developing standardized monitoring methods, such as at juvenile bypass systems (JBS’s), to better document numbers and timing of lamprey migrations at dams, and use biotelemetry tracking techniques to estimate survival potentials for different migration histories.

  7. Migration depth and residence time of juvenile salmonids in the forebays of hydropower dams prior to passage through turbines or juvenile bypass systems: implications for turbine-passage survival.

    Science.gov (United States)

    Li, Xinya; Deng, Zhiqun D; Brown, Richard S; Fu, Tao; Martinez, Jayson J; McMichael, Geoffrey A; Skalski, John R; Townsend, Richard L; Trumbo, Bradly A; Ahmann, Martin L; Renholds, Jon F

    2015-01-01

    Little is known about the three-dimensional depth distributions in rivers of individually marked fish that are in close proximity to hydropower facilities. Knowledge of the depth distributions of fish approaching dams can be used to understand how vulnerable fish are to injuries such as barotrauma as they pass through dams. To predict the possibility of barotrauma injury caused by pressure changes during turbine passage, it is necessary to understand fish behaviour relative to acclimation depth in dam forebays as they approach turbines. A guiding study was conducted using high-resolution three-dimensional tracking results of salmonids implanted with Juvenile Salmon Acoustic Telemetry System transmitters to investigate the depth distributions of subyearling and yearling Chinook salmon (Oncorhynchus tshawytscha) and juvenile steelhead (Oncorhynchus mykiss) passing two dams on the Snake River in Washington State. Multiple approaches were evaluated to describe the depth at which fish were acclimated, and statistical analyses were performed on large data sets extracted from ∼28 000 individually tagged fish during 2012 and 2013. Our study identified patterns of depth distributions of juvenile salmonids in forebays prior to passage through turbines or juvenile bypass systems. This research indicates that the median depth at which juvenile salmonids approached turbines ranged from 2.8 to 12.2 m, with the depths varying by species/life history, year, location (which dam) and diel period (between day and night). One of the most enlightening findings was the difference in dam passage associated with the diel period. The amount of time that turbine-passed fish spent in the immediate forebay prior to entering the powerhouse was much lower during the night than during the day. This research will allow scientists to understand turbine-passage survival better and enable them to assess more accurately the effects of dam passage on juvenile salmon survival.

  8. Effects of emergence time and early social rearing environment on behaviour of Atlantic salmon: consequences for juvenile fitness and smolt migration.

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    Martin H Larsen

    Full Text Available Consistent individual differences in behaviour have been well documented in a variety of animal taxa, but surprisingly little is known about the fitness and life-history consequences of such individual variation. In wild salmonids, the timing of fry emergence from gravel spawning nests has been suggested to be coupled with individual behavioural traits. Here, we further investigate the link between timing of spawning nest emergence and behaviour of Atlantic salmon (Salmo salar, test effects of social rearing environment on behavioural traits in fish with different emergence times, and assess whether behavioural traits measured in the laboratory predict growth, survival, and migration status in the wild. Atlantic salmon fry were sorted with respect to emergence time from artificial spawning nest into three groups: early, intermediate, and late. These emergence groups were hatchery-reared separately or in co-culture for four months to test effects of social rearing environment on behavioural traits. Twenty fish from each of the six treatment groups were then subjected to three individual-based behavioural tests: basal locomotor activity, boldness, and escape response. Following behavioural characterization, the fish were released into a near-natural experimental stream. Results showed differences in escape behaviour between emergence groups in a net restraining test, but the social rearing environment did not affect individual behavioural expression. Emergence time and social environment had no significant effects on survival, growth, and migration status in the stream, although migration propensity was 1.4 to 1.9 times higher for early emerging individuals that were reared separately. In addition, despite individuals showing considerable variation in behaviour across treatment groups, this was not translated into differences in growth, survival, and migration status. Hence, our study adds to the view that fitness (i.e., growth and survival and

  9. Effects of emergence time and early social rearing environment on behaviour of Atlantic salmon: consequences for juvenile fitness and smolt migration.

    Science.gov (United States)

    Larsen, Martin H; Johnsson, Jörgen I; Winberg, Svante; Wilson, Alexander D M; Hammenstig, David; Thörnqvist, Per-Ove; Midwood, Jonathan D; Aarestrup, Kim; Höglund, Erik

    2015-01-01

    Consistent individual differences in behaviour have been well documented in a variety of animal taxa, but surprisingly little is known about the fitness and life-history consequences of such individual variation. In wild salmonids, the timing of fry emergence from gravel spawning nests has been suggested to be coupled with individual behavioural traits. Here, we further investigate the link between timing of spawning nest emergence and behaviour of Atlantic salmon (Salmo salar), test effects of social rearing environment on behavioural traits in fish with different emergence times, and assess whether behavioural traits measured in the laboratory predict growth, survival, and migration status in the wild. Atlantic salmon fry were sorted with respect to emergence time from artificial spawning nest into three groups: early, intermediate, and late. These emergence groups were hatchery-reared separately or in co-culture for four months to test effects of social rearing environment on behavioural traits. Twenty fish from each of the six treatment groups were then subjected to three individual-based behavioural tests: basal locomotor activity, boldness, and escape response. Following behavioural characterization, the fish were released into a near-natural experimental stream. Results showed differences in escape behaviour between emergence groups in a net restraining test, but the social rearing environment did not affect individual behavioural expression. Emergence time and social environment had no significant effects on survival, growth, and migration status in the stream, although migration propensity was 1.4 to 1.9 times higher for early emerging individuals that were reared separately. In addition, despite individuals showing considerable variation in behaviour across treatment groups, this was not translated into differences in growth, survival, and migration status. Hence, our study adds to the view that fitness (i.e., growth and survival) and life

  10. Relationship of external fish condition to pathogen prevalence and out-migration survival in juvenile steelhead

    Science.gov (United States)

    Hostetter, N.J.; Evans, A.F.; Roby, D.D.; Collis, K.; Hawbecker, M.; Sandford, B.P.; Thompson, D.E.; Loge, F.J.

    2011-01-01

    Understanding how the external condition of juvenile salmonids is associated with internal measures of health and subsequent out-migration survival can be valuable for population monitoring programs. This study investigated the use of a rapid, nonlethal, external examination to assess the condition of run-of-the-river juvenile steelhead Oncorhynchus mykiss migrating from the Snake River to the Pacific Ocean. We compared the external condition (e.g., body injuries, descaling, external signs of disease, fin damage, and ectoparasite infestations) with (1) the internal condition of a steelhead as measured by the presence of selected pathogens detected by histopathology and polymerase chain reaction analysis and (2) out-migration survival through the Snake and Columbia rivers as determined by passive integrated transponder (PIT) tag technology. The results from steelhead captured and euthanized (n = 222) at Lower Monumental Dam on the lower Snake River in 2008 indicated that external condition was significantly correlated with selected measures of internal condition. The odds of testing positive for a pathogen were 39.2, 24.3, and 5.6 times greater for steelhead with severe or moderate external signs of disease or more than 20% descaling, respectively. Capture-recapture models of 22,451 PIT-tagged steelhead released at Lower Monumental Dam in 2007-2009 indicated that external condition was significantly correlated with juvenile survival. The odds of outmigration survival for steelhead with moderate or severe external signs of disease, more than 20% descaling, or severe fin damage were 5.7, 4.9, 1.6, and 1.3 times lower, respectively, than those for steelhead without these external conditions. This study effectively demonstrated that specific measures of external condition were associated with both the internal condition and out-migration survival of juvenile steelhead. ?? American Fisheries Society 2011.

  11. Lateral and vertical distribution of downstream migrating juvenile sea lamprey

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    Sotola, V. Alex; Miehls, Scott M.; Simard, Lee G.; Marsden, J. Ellen

    2018-01-01

    Sea lamprey is considered an invasive and nuisance species in the Laurentian Great Lakes, Lake Champlain, and the Finger Lakes of New York and is a major focus of control efforts. Currently, management practices focus on limiting the area of infestation using barriers to block migratory adults, and lampricides to kill ammocoetes in infested tributaries. No control efforts currently target the downstream-migrating post-metamorphic life stage which could provide another management opportunity. In order to apply control methods to this life stage, a better understanding of their downstream movement patterns is needed. To quantify spatial distribution of downstream migrants, we deployed fyke and drift nets laterally and vertically across the stream channel in two tributaries of Lake Champlain. Sea lamprey was not randomly distributed across the stream width and lateral distribution showed a significant association with discharge. Results indicated that juvenile sea lamprey is most likely to be present in the thalweg and at midwater depths of the stream channel. Further, a majority of the catch occurred during high flow events, suggesting an increase in downstream movement activity when water levels are higher than base flow. Discharge and flow are strong predictors of the distribution of out-migrating sea lamprey, thus managers will need to either target capture efforts in high discharge areas of streams or develop means to guide sea lamprey away from these areas.

  12. Effects of emergence time and early social rearing environment on behaviour of Atlantic salmon: Consequences for juvenile fitness and smolt migration

    DEFF Research Database (Denmark)

    Larsen, Martin Hage; Johnsson, Jörgen I.; Winberg, Svante

    2015-01-01

    -reared separately or in co-culture for four months to test effects of social rearing environment on behavioural traits. Twenty fish from each of the six treatment groups were then subjected to three individual-based behavioural tests: basal locomotor activity, boldness, and escape response. Following behavioural...... suggested to be coupled with individual behavioural traits. Here, we further investigate the link between timing of spawning nest emergence and behaviour of Atlantic salmon (Salmo salar), test effects of social rearing environment on behavioural traits in fish with different emergence times, and assess...... characterization, the fish were released into a near-natural experimental stream. Results showed differences in escape behaviour between emergence groups in a net restraining test, but the social rearing environment did not affect individual behavioural expression. Emergence time and social environment had...

  13. Turbulence investigation and reproduction for assisting downstream migrating juvenile salmonids, Part II of II: Effects of induced turbulence on behavior of juvenile salmon, 2001-2005 final report

    Science.gov (United States)

    Perry, R.; Farley , M.; Hansen, G.; Morse , J.; Rondorf, D.

    2005-01-01

    Passage through dams is a major source of mortality of anadromous juvenile salmonids because some populations must negotiate up to eight dams in Columbia and Snake rivers. Dams cause direct mortality when fish pass through turbines, but dams may also cause indirect mortality by altering migration conditions in rivers. Forebays immediately upstream of dams have decreased the water velocity of rivers and may contribute substantially to the total migration delay of juvenile salmonids. Recently, Coutant (2001a) suggested that in addition to low water velocities, lack of natural turbulence may contribute to migration delay by causing fish to lose directional cues. Coutant (2001a) further hypothesized that restoring turbulence in dam forebays may reduce migration delay by providing directional cues that allow fish to find passage routes more quickly (Coutant 2001a). Although field experiments have yielded proof of the concept of using induced turbulence to guide fish to safe passage routes, little is known about mechanisms actually causing behavioral changes. To test hypotheses about how turbulence influences movement and behavior of migrating juvenile salmonids, we conducted two types of controlled experiments at Cowlitz Falls Dam, Washington. A common measure of migration delay is the elapsed time between arrival at, and passage through, a dam. Therefore, for the first set of experiments, we tested the effect of induced turbulence on the elapsed time needed for fish to traverse through a raceway and pass over a weir at its downstream end (time trial experiment). If turbulence helps guide fish to passage routes, then fish should pass through the raceway quicker in the presence of appropriately scaled and directed turbulent cues. Second, little is known about how the physical properties of water movement provide directional cues to migrating juvenile salmonids. To examine the feasibility of guiding fish with turbulence, we tested whether directed turbulence could guide

  14. Spring northward juvenile migration of the Patagonian grenadier (Macruronus magellanicus from the Northwest Patagonian waters of Chile

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    Luis A Cubillos

    2015-11-01

    Full Text Available Important nursery grounds for Patagonian grenadier (Macruronus magellanicus are located mainly in the Northwest Patagonian Inner Sea (42ºS-44ºS, from which juvenile must to disperse or migrate offshore, then along the Chilean coast either northward or southward. The objective of this paper was to estimate northward spring juvenile migration of the Patagonian grenadier from nursery to feeding areas, which are located near Talcahuano (35º00’S-37º10’S. Length-frequency data (LFD were obtained from an acoustic survey carried out in November 1999, which covered from 35ºS to 47ºS. Generalized linear model was used to describe the presence of juvenile per latitude and depth, and to infer the origin and displacement of juveniles. Subsequently, LFD data were grouped according to latitudinal strata. Grouped LFD were decomposed into normal component groups, from which mean, standard deviation and proportion were estimated from the mixed LFD. The average length of the identified groups were sorted from south to north, and linked to compute significant increment in fish length and age per kilometers. The length increment per time was not due to growth, rather they was due to spatial displacement of juvenile from southern nursery grounds to northern feeding areas. Although homing to feeding areas and/or high residency (partial migration have been postulated, it seems that recruitment of juveniles to northern feeding areas are origintaed from NPIS nurseries. The West Wind Drift Current seems to be the main drive for dispersion of Patagonian grenadier to recruit northward in open waters along the continental shelf.

  15. Variability in Migration Routes Influences Early Marine Survival of Juvenile Salmon Smolts.

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    Nathan B Furey

    Full Text Available Variability in animal migratory behavior is expected to influence fitness, but few empirical examples demonstrating this relationship exist. The initial marine phase in the migration of juvenile salmon smolts has been identified as a potentially critical life history stage to overall population productivity, yet how fine-scale migration routes may influence survival are unknown. Large-scale acoustic telemetry studies have estimated survival rates of outmigrant Pacific salmon smolts through the Strait of Georgia (SOG along the British Columbian coastline to the Pacific Ocean, but these data have not been used to identify and characterize fine-scale movements. Data collected on over 850 sockeye salmon (Oncorhynchus nerka and steelhead (Oncorhynchus mykiss smolts detected at an array in the Strait of Georgia in 2004-2008 and 2010-2013 were analyzed to characterize migration routes and link movements to subsequent survival at an array 250 km further along the marine migration pathway. Both species exhibited disproportionate use of the most eastern route in the Strait of Georgia (Malaspina Strait. While many smolts moved across the northern Strait of Georgia acoustic array with no indication of long-term milling or large-scale east-to-west movements, large proportions (20-40% of sockeye and 30-50% of steelhead exhibited a different behavior, apparently moving in a westward or counterclockwise pattern. Variability in migratory behavior for both species was linked to subsequent survival through the Strait of Georgia. Survival for both species was influenced by initial east-to-west location, and sockeye were further influenced by migration timing and duration of time spent near the northern Strait of Georgia array. Westward movements result in a net transport of smolts from Malaspina Strait to the Strait of Georgia, particularly for steelhead. Counterclockwise movements may be due to the currents in this area during the time of outmigration, and the

  16. Goliath catfish spawning in the far western Amazon confirmed by the distribution of mature adults, drifting larvae and migrating juveniles.

    Science.gov (United States)

    Barthem, Ronaldo B; Goulding, Michael; Leite, Rosseval G; Cañas, Carlos; Forsberg, Bruce; Venticinque, Eduardo; Petry, Paulo; Ribeiro, Mauro L de B; Chuctaya, Junior; Mercado, Armando

    2017-02-06

    We mapped the inferred long-distance migrations of four species of Amazonian goliath catfishes (Brachyplatystoma rousseauxii, B. platynemum, B. juruense and B. vaillantii) based on the presence of individuals with mature gonads and conducted statistical analysis of the expected long-distance downstream migrations of their larvae and juveniles. By linking the distribution of larval, juvenile and mature adult size classes across the Amazon, the results showed: (i) that the main spawning regions of these goliath catfish species are in the western Amazon; (ii) at least three species-B. rousseauxii, B. platynemum, and B. juruense-spawn partially or mainly as far upstream as the Andes; (iii) the main spawning area of B. rousseauxii is in or near the Andes; and (iv) the life history migration distances of B. rousseauxii are the longest strictly freshwater fish migrations in the world. These results provide an empirical baseline for tagging experiments, life histories extrapolated from otolith microchemistry interpretations and other methods to establish goliath catfish migratory routes, their seasonal timing and possible return (homing) to western headwater tributaries where they were born.

  17. The minor immigrant and the effects of juvenile migration in Europe

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    Andy Corneliu Pusca

    2015-12-01

    Full Text Available In the civil law and the international law, the minor immigrants are the new protagonists of migratory processes and constitute a fundamental subject. During the last decade, the presence of minors in the most important migration phenomenon has united migrations worldwide and the numbers increased significantly. There is no universal definition of the minor immigrant. This paper aims to describe the concept of minor immigrant, the effects of juvenile migration on the EU Member States and the measures to be taken in order to prevent the negative aspects and to reduce the human costs of migration processes. The method applied is the creation of placement and protection models able to comply with the obligations imposed by international conventions, model that is far from being considered adequate, since the convictions of the European Court of Human Rights prove the lack of practice in the field.

  18. Hydraulic Characteristics of the Lower Snake River During Periods of Juvenile Fall Chinook Migration

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    Cook, Chris B.; Dibrani, Berhon; Richmond, Marshall C.; Bleich, Matthew D.; Titzler, P. Scott; Fu, Tao

    2006-01-30

    This report documents a four-year study to assess hydraulic conditions in the lower Snake River. The work was conducted for the Bonneville Power Administration, U.S. Department of Energy, by the Pacific Northwest National Laboratory. Cold water released from the Dworshak Reservoir hypolimnion during mid- to late-summer months cools the Clearwater River far below equilibrium temperature. The volume of released cold water augments the Clearwater River, and the combined total discharge is on the order of the Snake River discharge when the two rivers meet at their confluence near the upstream edge of Lower Granite Reservoir. With typical temperature differences between the Clearwater and Snake rivers of 10°C or more during July and August, the density difference between the two rivers during summer flow augmentation periods is sufficient to stratify Lower Granite Reservoir as well as the other three reservoirs downstream. Because cooling of the river is desirable for migrating juvenile fall Chinook salmon (Oncorhynchus tshawytscha) during this same time period, the amount of mixing and cold water entrained into Lower Granite Reservoir’s epilimnion at the Clearwater/Snake River confluence is of key biological importance to juvenile fall Chinook salmon. Data collected during this project indicates the three reservoirs downstream of Lower Granite also stratify as direct result of flow augmentation from Dworshak Reservoir. These four lower Snake reservoirs are also heavily influenced by wind forcing at the water’s surface, and during periods of low river discharge, often behave like a two-layer lake. During these periods of stratification, lower river discharge, and wind forcing, the water in the upper layer of the reservoir is held in place or moves slightly upstream. This upper layer is also exposed to surface heating and may warm up to temperatures close to equilibrium temperature. The depth of this upper warm layer and its direction of travel may also be of key

  19. Elastic least-squares reverse time migration

    KAUST Repository

    Feng, Zongcai; Schuster, Gerard T.

    2016-01-01

    Elastic least-squares reverse time migration (LSRTM) is used to invert synthetic particle-velocity data and crosswell pressure field data. The migration images consist of both the P- and Svelocity perturbation images. Numerical tests on synthetic and field data illustrate the advantages of elastic LSRTM over elastic reverse time migration (RTM). In addition, elastic LSRTM images are better focused and have better reflector continuity than do the acoustic LSRTM images.

  20. Elastic least-squares reverse time migration

    KAUST Repository

    Feng, Zongcai

    2016-09-06

    Elastic least-squares reverse time migration (LSRTM) is used to invert synthetic particle-velocity data and crosswell pressure field data. The migration images consist of both the P- and Svelocity perturbation images. Numerical tests on synthetic and field data illustrate the advantages of elastic LSRTM over elastic reverse time migration (RTM). In addition, elastic LSRTM images are better focused and have better reflector continuity than do the acoustic LSRTM images.

  1. Multisource Least-squares Reverse Time Migration

    KAUST Repository

    Dai, Wei

    2012-01-01

    is implemented with random time-shift and random source polarity encoding functions. Numerical tests on the 2D HESS VTI data show that the multisource LSRTM algorithm suppresses migration artifacts, balances the amplitudes, improves image resolution, and reduces

  2. Regional-scale migrations and habitat use of juvenile lemon sharks (Negaprion brevirostris) in the US South Atlantic.

    Science.gov (United States)

    Reyier, Eric A; Franks, Bryan R; Chapman, Demian D; Scheidt, Douglas M; Stolen, Eric D; Gruber, Samuel H

    2014-01-01

    Resolving the geographic extent and timing of coastal shark migrations, as well as their environmental cues, is essential for refining shark management strategies in anticipation of increasing anthropogenic stressors to coastal ecosystems. We employed a regional-scale passive acoustic telemetry array encompassing 300 km of the east Florida coast to assess what factors influence site fidelity of juvenile lemon sharks (Negaprion brevirostris) to an exposed coastal nursery at Cape Canaveral, and to document the timing and rate of their seasonal migrations. Movements of 54 juvenile lemon sharks were monitored for three years with individuals tracked for up to 751 days. While most sharks demonstrated site fidelity to the Cape Canaveral region December through February under typical winter water temperatures, historically extreme declines in ocean temperature were accompanied by rapid and often temporary, southward displacements of up to 190 km along the Florida east coast. From late February through April each year, most sharks initiated a northward migration at speeds of up to 64 km day(-1) with several individuals then detected in compatible estuarine telemetry arrays in Georgia and South Carolina up to 472 km from release locations. Nineteen sharks returned for a second or even third consecutive winter, thus demonstrating strong seasonal philopatry to the Cape Canaveral region. The long distance movements and habitat associations of immature lemon sharks along the US southeast coast contrast sharply with the natal site fidelity observed in this species at other sites in the western Atlantic Ocean. These findings validate the existing multi-state management strategies now in place. Results also affirm the value of collaborative passive arrays for resolving seasonal movements and habitat preferences of migratory coastal shark species not easily studied with other tagging techniques.

  3. Visualizing Human Migration Trhough Space and Time

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    Zambotti, G.; Guan, W.; Gest, J.

    2015-07-01

    Human migration has been an important activity in human societies since antiquity. Since 1890, approximately three percent of the world's population has lived outside of their country of origin. As globalization intensifies in the modern era, human migration persists even as governments seek to more stringently regulate flows. Understanding this phenomenon, its causes, processes and impacts often starts from measuring and visualizing its spatiotemporal patterns. This study builds a generic online platform for users to interactively visualize human migration through space and time. This entails quickly ingesting human migration data in plain text or tabular format; matching the records with pre-established geographic features such as administrative polygons; symbolizing the migration flow by circular arcs of varying color and weight based on the flow attributes; connecting the centroids of the origin and destination polygons; and allowing the user to select either an origin or a destination feature to display all flows in or out of that feature through time. The method was first developed using ArcGIS Server for world-wide cross-country migration, and later applied to visualizing domestic migration patterns within China between provinces, and between states in the United States, all through multiple years. The technical challenges of this study include simplifying the shapes of features to enhance user interaction, rendering performance and application scalability; enabling the temporal renderers to provide time-based rendering of features and the flow among them; and developing a responsive web design (RWD) application to provide an optimal viewing experience. The platform is available online for the public to use, and the methodology is easily adoptable to visualizing any flow, not only human migration but also the flow of goods, capital, disease, ideology, etc., between multiple origins and destinations across space and time.

  4. Multiples least-squares reverse time migration

    KAUST Repository

    Zhang, Dongliang; Zhan, Ge; Dai, Wei; Schuster, Gerard T.

    2013-01-01

    To enhance the image quality, we propose multiples least-squares reverse time migration (MLSRTM) that transforms each hydrophone into a virtual point source with a time history equal to that of the recorded data. Since each recorded trace is treated

  5. Multiples least-squares reverse time migration

    KAUST Repository

    Zhang, Dongliang

    2013-01-01

    To enhance the image quality, we propose multiples least-squares reverse time migration (MLSRTM) that transforms each hydrophone into a virtual point source with a time history equal to that of the recorded data. Since each recorded trace is treated as a virtual source, knowledge of the source wavelet is not required. Numerical tests on synthetic data for the Sigsbee2B model and field data from Gulf of Mexico show that MLSRTM can improve the image quality by removing artifacts, balancing amplitudes, and suppressing crosstalk compared to standard migration of the free-surface multiples. The potential liability of this method is that multiples require several roundtrips between the reflector and the free surface, so that high frequencies in the multiples are attenuated compared to the primary reflections. This can lead to lower resolution in the migration image compared to that computed from primaries.

  6. Elastic least-squares reverse time migration

    KAUST Repository

    Feng, Zongcai

    2017-03-08

    We use elastic least-squares reverse time migration (LSRTM) to invert for the reflectivity images of P- and S-wave impedances. Elastic LSRTMsolves the linearized elastic-wave equations for forward modeling and the adjoint equations for backpropagating the residual wavefield at each iteration. Numerical tests on synthetic data and field data reveal the advantages of elastic LSRTM over elastic reverse time migration (RTM) and acoustic LSRTM. For our examples, the elastic LSRTM images have better resolution and amplitude balancing, fewer artifacts, and less crosstalk compared with the elastic RTM images. The images are also better focused and have better reflector continuity for steeply dipping events compared to the acoustic LSRTM images. Similar to conventional leastsquares migration, elastic LSRTM also requires an accurate estimation of the P- and S-wave migration velocity models. However, the problem remains that, when there are moderate errors in the velocity model and strong multiples, LSRTMwill produce migration noise stronger than that seen in the RTM images.

  7. Elastic least-squares reverse time migration

    KAUST Repository

    Feng, Zongcai; Schuster, Gerard T.

    2017-01-01

    We use elastic least-squares reverse time migration (LSRTM) to invert for the reflectivity images of P- and S-wave impedances. Elastic LSRTMsolves the linearized elastic-wave equations for forward modeling and the adjoint equations for backpropagating the residual wavefield at each iteration. Numerical tests on synthetic data and field data reveal the advantages of elastic LSRTM over elastic reverse time migration (RTM) and acoustic LSRTM. For our examples, the elastic LSRTM images have better resolution and amplitude balancing, fewer artifacts, and less crosstalk compared with the elastic RTM images. The images are also better focused and have better reflector continuity for steeply dipping events compared to the acoustic LSRTM images. Similar to conventional leastsquares migration, elastic LSRTM also requires an accurate estimation of the P- and S-wave migration velocity models. However, the problem remains that, when there are moderate errors in the velocity model and strong multiples, LSRTMwill produce migration noise stronger than that seen in the RTM images.

  8. Rural-to-Urban Migration, Strain, and Juvenile Delinquency: A Study of Eighth-Grade Students in Guangzhou, China.

    Science.gov (United States)

    Lo, Celia C; Cheng, Tyrone C; Bohm, Maggie; Zhong, Hua

    2018-02-01

    This examination of minor and serious delinquency among eighth graders in a large southern Chinese city, Guangzhou, also compared groups of these students, observing differences between the delinquency of migrants and that of urban natives. Data used were originally collected for the study "Stuck in the City: Migration and Delinquency Among Migrant Adolescents in Guangzhou." The present study asked whether and how various sources of strain and social control factors explained students' delinquency, questioning how meaningfully migration status moderated several of the observed delinquency relationships. Of students in the sample, 741 reported being natives of Guangzhou, and 497 reported migrating to Guangzhou from a rural area. The study conceptualized internal migration as a strain factor leading to delinquency, but the analyses did not suggest direct association between internal migration and delinquency. Results generally supported Agnew's theory, and, what's more, they tended to confirm that migration status moderated juvenile delinquency.

  9. Multisource Least-squares Reverse Time Migration

    KAUST Repository

    Dai, Wei

    2012-12-01

    Least-squares migration has been shown to be able to produce high quality migration images, but its computational cost is considered to be too high for practical imaging. In this dissertation, a multisource least-squares reverse time migration algorithm (LSRTM) is proposed to increase by up to 10 times the computational efficiency by utilizing the blended sources processing technique. There are three main chapters in this dissertation. In Chapter 2, the multisource LSRTM algorithm is implemented with random time-shift and random source polarity encoding functions. Numerical tests on the 2D HESS VTI data show that the multisource LSRTM algorithm suppresses migration artifacts, balances the amplitudes, improves image resolution, and reduces crosstalk noise associated with the blended shot gathers. For this example, multisource LSRTM is about three times faster than the conventional RTM method. For the 3D example of the SEG/EAGE salt model, with comparable computational cost, multisource LSRTM produces images with more accurate amplitudes, better spatial resolution, and fewer migration artifacts compared to conventional RTM. The empirical results suggest that the multisource LSRTM can produce more accurate reflectivity images than conventional RTM does with similar or less computational cost. The caveat is that LSRTM image is sensitive to large errors in the migration velocity model. In Chapter 3, the multisource LSRTM algorithm is implemented with frequency selection encoding strategy and applied to marine streamer data, for which traditional random encoding functions are not applicable. The frequency-selection encoding functions are delta functions in the frequency domain, so that all the encoded shots have unique non-overlapping frequency content. Therefore, the receivers can distinguish the wavefield from each shot according to the frequencies. With the frequency-selection encoding method, the computational efficiency of LSRTM is increased so that its cost is

  10. De‐blending reverse‐time migration

    KAUST Repository

    Fei, Tong W.

    2010-10-17

    Reverse‐time migration (RTM), based on the full two‐way wave equation, has gained interest and become a popular imaging tool for complex structures in the last few years. The method is well‐known for its ability to better image the steeply dipping and overturned structures than the migration methods based on the one‐way wave equation extrapolation. However, the RTM image often contains low frequency and back‐scattering noise, and the imaging quality is sensitive to the migration velocity. In order to improve the RTM imaging quality and make the RTM image less sensitive to the velocity model, we developed an RTM de‐blending technique which separates upgoing and downgoing source and receiver wavefields, and then use them to construct final RTM images. Test results show that decomposed images obtained from only the downgoing source and receiver wavefields are less sensitive to velocity. It removes unwanted noise and migration artifacts from conventional RTM, and the imaging quality is greatly improved compared with a conventional RTM image.

  11. De‐blending reverse‐time migration

    KAUST Repository

    Fei, Tong W.; Luo, Yi; Schuster, Gerard T.

    2010-01-01

    Reverse‐time migration (RTM), based on the full two‐way wave equation, has gained interest and become a popular imaging tool for complex structures in the last few years. The method is well‐known for its ability to better image the steeply dipping and overturned structures than the migration methods based on the one‐way wave equation extrapolation. However, the RTM image often contains low frequency and back‐scattering noise, and the imaging quality is sensitive to the migration velocity. In order to improve the RTM imaging quality and make the RTM image less sensitive to the velocity model, we developed an RTM de‐blending technique which separates upgoing and downgoing source and receiver wavefields, and then use them to construct final RTM images. Test results show that decomposed images obtained from only the downgoing source and receiver wavefields are less sensitive to velocity. It removes unwanted noise and migration artifacts from conventional RTM, and the imaging quality is greatly improved compared with a conventional RTM image.

  12. Turbulence Investigation and Reproduction for Assisting Downstream Migrating Juvenile Salmonids, Part I of II, 2001-2002 Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Hotchkiss, Rollin H. (Washington State University, Department of Civil and Environmental Engineers, Albrook Hydraulics Laboratory)

    2002-12-01

    Turbulence in gravel bed rivers plays a critical role in most stream processes including contaminant and nutrient transport, aquatic habitat selection, and natural channel design. While most hydraulic designs and fluid models are based on bulk velocity, migrating juvenile salmon experience and react to the temporally varied turbulent fluctuations. Without properly understanding and accounting for the continuous turbulent motions proper fishway design and guidance are impossible. Matching temporally varied flow to fish reactions is the key to guiding juvenile salmonids to safe passageways. While the ideal solution to fish guidance design would be to use specific fluid action-fish reaction mechanisms, such concrete cause and effect relations have not been established. One way to approach the problem of guidance is to hypothesize that in an environment lacking obvious bulk flow cues (like the reservoir environment), turbulent flow conditions similar to those experienced by juvenile salmonids in natural migration corridors will be attractive to juvenile salmonids. Proof of this hypothesis requires three steps: (1) gathering data on turbulence characteristics in natural migration corridors, (2) reproduction of the turbulence parameters in a controlled environment, and (3) testing the reproduced turbulence on actively migrating juvenile salmonids for increased passage efficiencies. The results from the third step have not been finalized, therefore this report will focus on understanding turbulent processes in gravel bed rivers and reproduction of turbulence in controlled environments for use in fish passage technologies. The purposes of this report are to (1) present data collected in natural gravel bed rivers, (2) present a simple method for reproduction of appropriate turbulence levels in a controlled environment, (3) compare these results to those from one prototype surface collector (PSC), and (4) discuss the implications on fish passage design.

  13. Radio telemetry data - Characterizing migration and survival for juvenile Snake River sockeye salmon between the upper Salmon River basin and Lower Granite Dam

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This project estimates survival and characterizes the migration of juvenile sockeye salmon between the upper Salmon River basin in central Idaho and Lower Granite...

  14. Spatial segregation within the spawning migration of North Eastern Atlantic mackerel (Scomber scombrus as indicated by juvenile growth patterns.

    Directory of Open Access Journals (Sweden)

    Teunis Jansen

    Full Text Available A comparison of growth data (fish length with latitude shows that southern juvenile mackerel attain a greater length than those originating from further north before growth ceases during their first winter. A similar significant relationship was found between the growth in the first year (derived from the otolith inner winter ring and latitude for adult mackerel spawning between 44°N (Bay of Biscay and 54°N (west of Ireland. These observations are consistent with spatial segregation of the spawning migration; the further north that the fish were hatched, the further north they will tend to spawn. No such relationship was found in mackerel spawning at more northerly latitudes, possibly as a consequence of increased spatial mixing in a more energetic regime with stronger currents. This study provides previously lacking support for spawning segregation behaviour among North East Atlantic mackerel--an important step towards understanding the migratory behaviour of mackerel and hence the spatiotemporal distribution dynamics around spawning time.

  15. Three-dimensional migration behavior of juvenile salmonids in reservoirs and near dams

    OpenAIRE

    Li, Xinya; Deng, Zhiqun D.; Fu, Tao; Brown, Richard S.; Martinez, Jayson J.; McMichael, Geoffrey A.; Trumbo, Bradly A.; Ahmann, Martin L.; Renholds, Jon F.; Skalski, John R.; Townsend, Richard L.

    2018-01-01

    To acquire 3-D tracking data on juvenile salmonids, Juvenile Salmon Acoustic Telemetry System (JSATS) cabled hydrophone arrays were deployed in the forebays of two dams on the Snake River and at a mid-reach reservoir between the dams. The depth distributions of fish were estimated by statistical analyses performed on large 3-D tracking data sets from ~33,500 individual acoustic tagged yearling and subyearling Chinook salmon and juvenile steelhead at the two dams in 2012 and subyearling Chinoo...

  16. Hydraulic Characteristics of the Lower Snake River during Periods of Juvenile Fall Chinook Salmon Migration, 2002-2006 Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Cook, C.; Dibrani, B.; Richmond, M.; Bleich, M.; Titzler, P..; Fu, T. [Pacific Northwest National Laboratory

    2006-01-01

    This report documents a four-year study to assess hydraulic conditions in the lower Snake River. The work was conducted for the Bonneville Power Administration, U.S. Department of Energy, by the Pacific Northwest National Laboratory. Cold water released from the Dworshak Reservoir hypolimnion during mid- to late-summer months cools the Clearwater River far below equilibrium temperature. The volume of released cold water augments the Clearwater River, and the combined total discharge is on the order of the Snake River discharge when the two rivers meet at their confluence near the upstream edge of Lower Granite Reservoir. With typical temperature differences between the Clearwater and Snake rivers of 10 C or more during July and August, the density difference between the two rivers during summer flow augmentation periods is sufficient to stratify Lower Granite Reservoir as well as the other three reservoirs downstream. Because cooling of the river is desirable for migrating juvenile fall Chinook salmon (Oncorhynchus tshawytscha) during this same time period, the amount of mixing and cold water entrained into Lower Granite Reservoir's epilimnion at the Clearwater/Snake River confluence is of key biological importance. Data collected during this project indicates the three reservoirs downstream of Lower Granite also stratify as direct result of flow augmentation from Dworshak Reservoir. These four reservoirs are also heavily influenced by wind forcing at the water's surface and during periods of low river discharge often behave like a two-layer lake. During these periods of stratification, lower river discharge, and wind forcing, the water in the upper layer of the reservoir is held in place or moves slightly upstream. This upper layer is also exposed to surface heating and may warm up to temperatures close to equilibrium temperature. The thickness (depth) of this upper warm layer and its direction of travel may be of key biological importance to juvenile

  17. Anti-Aliasing filter for reverse-time migration

    KAUST Repository

    Zhan, Ge

    2012-01-01

    We develop an anti-aliasing filter for reverse-time migration (RTM). It is similar to the traditional anti-aliasing filter used for Kirchhoff migration in that it low-pass filters the migration operator so that the dominant wavelength in the operator is greater than two times the trace sampling interval, except it is applied to both primary and multiple reflection events. Instead of applying this filter to the data in the traditional RTM operation, we apply the anti-aliasing filter to the generalized diffraction-stack migration operator. This gives the same migration image as computed by anti-aliased RTM. Download

  18. Fitness consequences of timing of migration and breeding in cormorants.

    Directory of Open Access Journals (Sweden)

    Phillip Gienapp

    Full Text Available In most bird species timing of breeding affects reproductive success whereby early breeding is favoured. In migratory species migration time, especially arrival at the breeding grounds, and breeding time are expected to be correlated. Consequently, migration time should also have fitness consequences. However, in contrast to breeding time, evidence for fitness consequences of migration time is much more limited. Climate change has been shown to negatively affect the synchrony between trophic levels thereby leading to directional selection on timing but again direct evidence in avian migration time is scarce. We here analysed fitness consequences of migration and breeding time in great cormorants and tested whether climate change has led to increased selection on timing using a long-term data set from a breeding colony on the island of Vorsø (Denmark. Reproductive success, measured as number of fledglings, correlated with breeding time and arrival time at the colony and declined during the season. This seasonal decline became steeper during the study period for both migration and breeding time and was positively correlated to winter/spring climate, i.e. selection was stronger after warmer winters/springs. However, the increasing selection pressure on timing seems to be unrelated to climate change as the climatic variables that were related to selection strength did not increase during the study period. There is indirect evidence that phenology or abundances of preferred prey species have changed which could have altered selection on timing of migration and breeding.

  19. Least-squares reverse time migration of multiples

    KAUST Repository

    Zhang, Dongliang; Schuster, Gerard T.

    2013-01-01

    The theory of least-squares reverse time migration of multiples (RTMM) is presented. In this method, least squares migration (LSM) is used to image free-surface multiples where the recorded traces are used as the time histories of the virtual

  20. Multi-source least-squares reverse time migration

    KAUST Repository

    Dai, Wei

    2012-06-15

    Least-squares migration has been shown to improve image quality compared to the conventional migration method, but its computational cost is often too high to be practical. In this paper, we develop two numerical schemes to implement least-squares migration with the reverse time migration method and the blended source processing technique to increase computation efficiency. By iterative migration of supergathers, which consist in a sum of many phase-encoded shots, the image quality is enhanced and the crosstalk noise associated with the encoded shots is reduced. Numerical tests on 2D HESS VTI data show that the multisource least-squares reverse time migration (LSRTM) algorithm suppresses migration artefacts, balances the amplitudes, improves image resolution and reduces crosstalk noise associated with the blended shot gathers. For this example, the multisource LSRTM is about three times faster than the conventional RTM method. For the 3D example of the SEG/EAGE salt model, with a comparable computational cost, multisource LSRTM produces images with more accurate amplitudes, better spatial resolution and fewer migration artefacts compared to conventional RTM. The empirical results suggest that multisource LSRTM can produce more accurate reflectivity images than conventional RTM does with a similar or less computational cost. The caveat is that the LSRTM image is sensitive to large errors in the migration velocity model. © 2012 European Association of Geoscientists & Engineers.

  1. Multi-source least-squares reverse time migration

    KAUST Repository

    Dai, Wei; Fowler, Paul J.; Schuster, Gerard T.

    2012-01-01

    Least-squares migration has been shown to improve image quality compared to the conventional migration method, but its computational cost is often too high to be practical. In this paper, we develop two numerical schemes to implement least-squares migration with the reverse time migration method and the blended source processing technique to increase computation efficiency. By iterative migration of supergathers, which consist in a sum of many phase-encoded shots, the image quality is enhanced and the crosstalk noise associated with the encoded shots is reduced. Numerical tests on 2D HESS VTI data show that the multisource least-squares reverse time migration (LSRTM) algorithm suppresses migration artefacts, balances the amplitudes, improves image resolution and reduces crosstalk noise associated with the blended shot gathers. For this example, the multisource LSRTM is about three times faster than the conventional RTM method. For the 3D example of the SEG/EAGE salt model, with a comparable computational cost, multisource LSRTM produces images with more accurate amplitudes, better spatial resolution and fewer migration artefacts compared to conventional RTM. The empirical results suggest that multisource LSRTM can produce more accurate reflectivity images than conventional RTM does with a similar or less computational cost. The caveat is that the LSRTM image is sensitive to large errors in the migration velocity model. © 2012 European Association of Geoscientists & Engineers.

  2. Migrating to a real-time distributed parallel simulator architecture

    CSIR Research Space (South Africa)

    Duvenhage, B

    2007-07-01

    Full Text Available A legacy non-distributed logical time simulator is migrated to a distributed architecture to parallelise execution. The existing Discrete Time System Specification (DTSS) modelling formalism is retained to simplify the reuse of existing models...

  3. Tracing of the Bile-chemotactic migration of juvenile Clonorchis sinensis in rabbits by PET-CT.

    Directory of Open Access Journals (Sweden)

    Tae Im Kim

    2011-12-01

    Full Text Available BACKGROUND: Adult Clonorchis sinensis live in the bile duct and cause clonorchiasis. It is known that the C. sinensis metacercariae excyst in the duodenum and migrate up to the bile duct through the common bile duct. However, no direct evidence is available on the in vivo migration of newly excysted C. sinensis juveniles (CsNEJs. Advanced imaging technologies now allow the in vivo migration and localization to be visualized. In the present study, we sought to determine how sensitively CsNEJs respond to bile and how fast they migrate to the intrahepatic bile duct using PET-CT. METHODOLOGY/PRINCIPAL FINDINGS: CsNEJs were radiolabeled with (18F-fluorodeoxyglucose ((18F-FDG. Rabbits with a gallbladder contraction response to cholecystokinin-8 (CCK-8 injection were pre-screened using cholescintigraphy. In these rabbits, gallbladders contracted by 50% in volume at an average of 11.5 min post-injection. The four rabbits examined were kept anesthetized and a catheter inserted into the mid duodenum. Gallbladder contraction was stimulated by injecting CCK-8 (20 ng/kg every minute over the experiment. Anatomical images were acquired by CT initially and dynamic PET was then carried out for 90 min with a 3-min acquisition per frame. Twelve minutes after CCK-8 injection, about 3,000 (18F-FDG-labeled CsNEJs were inoculated into the mid duodenum through the catheter. Photon signals were detected in the liver 7-9 min after CsNEJs inoculation, and these then increased in the whole liver with stronger intensity in the central area, presenting that the CsNEJs were arriving at the intrahepatic bile ducts. CONCLUSION: In the duodenum, CsNEJs immediately sense bile and migrate quickly with bile-chemotaxis to reach the intrahepatic bile ducts by way of the ampulla of Vater.

  4. Reverse time migration by Krylov subspace reduced order modeling

    Science.gov (United States)

    Basir, Hadi Mahdavi; Javaherian, Abdolrahim; Shomali, Zaher Hossein; Firouz-Abadi, Roohollah Dehghani; Gholamy, Shaban Ali

    2018-04-01

    Imaging is a key step in seismic data processing. To date, a myriad of advanced pre-stack depth migration approaches have been developed; however, reverse time migration (RTM) is still considered as the high-end imaging algorithm. The main limitations associated with the performance cost of reverse time migration are the intensive computation of the forward and backward simulations, time consumption, and memory allocation related to imaging condition. Based on the reduced order modeling, we proposed an algorithm, which can be adapted to all the aforementioned factors. Our proposed method benefit from Krylov subspaces method to compute certain mode shapes of the velocity model computed by as an orthogonal base of reduced order modeling. Reverse time migration by reduced order modeling is helpful concerning the highly parallel computation and strongly reduces the memory requirement of reverse time migration. The synthetic model results showed that suggested method can decrease the computational costs of reverse time migration by several orders of magnitudes, compared with reverse time migration by finite element method.

  5. Comparative evaluation of molecular diagnostic tests for Nucleospora salmonis and prevalence in migrating juvenile salmonids from the Snake River, USA

    Science.gov (United States)

    Badil, Samantha; Elliott, Diane G.; Kurobe, Tomofumi; Hedrick, Ronald P.; Clemens, Kathy; Blair, Marilyn; Purcell, Maureen K.

    2011-01-01

    Nucleospora salmonis is an intranuclear microsporidian that primarily infects lymphoblast cells and contributes to chronic lymphoblastosis and a leukemia-like condition in a range of salmonid species. The primary goal of this study was to evaluate the prevalence of N. salmonis in out-migrating juvenile hatchery and wild Chinook salmon Oncorhynchus tshawytscha and steelhead O. mykiss from the Snake River in the U.S. Pacific Northwest. To achieve this goal, we first addressed the following concerns about current molecular diagnostic tests for N. salmonis: (1) nonspecific amplification patterns by the published nested polymerase chain reaction (nPCR) test, (2) incomplete validation of the published quantitative PCR (qPCR) test, and (3) whether N. salmonis can be detected reliably from nonlethal samples. Here, we present an optimized nPCR protocol that eliminates nonspecific amplification. During validation of the published qPCR test, our laboratory developed a second qPCR test that targeted a different gene sequence and used different probe chemistry for comparison purposes. We simultaneously evaluated the two different qPCR tests for N. salmonis and found that both assays were highly specific, sensitive, and repeatable. The nPCR and qPCR tests had good overall concordance when DNA samples derived from both apparently healthy and clinically diseased hatchery rainbow trout were tested. Finally, we demonstrated that gill snips were a suitable tissue for nonlethal detection of N. salmonis DNA in juvenile salmonids. Monitoring of juvenile salmonid fish in the Snake River over a 3-year period revealed low prevalence of N. salmonis in hatchery and wild Chinook salmon and wild steelhead but significantly higher prevalence in hatchery-derived steelhead. Routine monitoring of N. salmonis is not performed for all hatchery steelhead populations. At present, the possible contribution of this pathogen to delayed mortality of steelhead has not been determined.

  6. Least squares reverse time migration of controlled order multiples

    Science.gov (United States)

    Liu, Y.

    2016-12-01

    Imaging using the reverse time migration of multiples generates inherent crosstalk artifacts due to the interference among different order multiples. Traditionally, least-square fitting has been used to address this issue by seeking the best objective function to measure the amplitude differences between the predicted and observed data. We have developed an alternative objective function by decomposing multiples into different orders to minimize the difference between Born modeling predicted multiples and specific-order multiples from observational data in order to attenuate the crosstalk. This method is denoted as the least-squares reverse time migration of controlled order multiples (LSRTM-CM). Our numerical examples demonstrated that the LSRTM-CM can significantly improve image quality compared with reverse time migration of multiples and least-square reverse time migration of multiples. Acknowledgments This research was funded by the National Nature Science Foundation of China (Grant Nos. 41430321 and 41374138).

  7. Plane-wave least-squares reverse-time migration

    KAUST Repository

    Dai, Wei

    2013-06-03

    A plane-wave least-squares reverse-time migration (LSRTM) is formulated with a new parameterization, where the migration image of each shot gather is updated separately and an ensemble of prestack images is produced along with common image gathers. The merits of plane-wave prestack LSRTM are the following: (1) plane-wave prestack LSRTM can sometimes offer stable convergence even when the migration velocity has bulk errors of up to 5%; (2) to significantly reduce computation cost, linear phase-shift encoding is applied to hundreds of shot gathers to produce dozens of plane waves. Unlike phase-shift encoding with random time shifts applied to each shot gather, plane-wave encoding can be effectively applied to data with a marine streamer geometry. (3) Plane-wave prestack LSRTM can provide higher-quality images than standard reverse-time migration. Numerical tests on the Marmousi2 model and a marine field data set are performed to illustrate the benefits of plane-wave LSRTM. Empirical results show that LSRTM in the plane-wave domain, compared to standard reversetime migration, produces images efficiently with fewer artifacts and better spatial resolution. Moreover, the prestack image ensemble accommodates more unknowns to makes it more robust than conventional least-squares migration in the presence of migration velocity errors. © 2013 Society of Exploration Geophysicists.

  8. Survival Estimates for the Passage of Spring-Migrating Juvenile Salmonids through Snake and Columbia River Dams and Reservoirs, 2001-2002 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Zabel, Richard; Williams, John G.; Smith, Steven G. (Northwest and Alaska Fisheries Science Center, Fish Ecology Division, Seattle, WA)

    2002-06-01

    In 2001, the National Marine Fisheries Service and the University of Washington completed the ninth year of a study to estimate survival and travel time of juvenile salmonids (Oncorhynchus spp.) passing through dams and reservoirs on the Snake and Columbia Rivers. All estimates were derived from passive integrated transponder (PIT)-tagged fish. We PIT tagged and released at Lower Granite Dam a total of 17,028 hatchery and 3,550 wild steelhead. In addition, we utilized fish PIT tagged by other agencies at traps and hatcheries upstream of the hydropower system and sites within the hydropower system. PIT-tagged smolts were detected at interrogation facilities at Lower Granite, Little Goose, Lower Monumental, McNary, John Day, and Bonneville Dams and in the PIT-tag detector trawl operated in the Columbia River estuary. Survival estimates were calculated using the Single-Release Model. Primary research objectives in 2001 were to: (1) estimate reach and project survival and travel time in the Snake and Columbia Rivers throughout the yearling chinook salmon and steelhead migrations; (2) evaluate relationships between survival estimates and migration conditions; and (3) evaluate the survival-estimation models under prevailing conditions. This report provides reach survival and travel time estimates for 2001 for PIT-tagged yearling chinook salmon and steelhead (hatchery and wild) in the Snake and Columbia Rivers. Results are reported primarily in the form of tables and figures with a minimum of text. More details on methodology and statistical models used are provided in previous reports cited in the text. Results for summer-migrating chinook salmon will be reported separately.

  9. Plane-wave Least-squares Reverse Time Migration

    KAUST Repository

    Dai, Wei

    2012-11-04

    Least-squares reverse time migration is formulated with a new parameterization, where the migration image of each shot is updated separately and a prestack image is produced with common image gathers. The advantage is that it can offer stable convergence for least-squares migration even when the migration velocity is not completely accurate. To significantly reduce computation cost, linear phase shift encoding is applied to hundreds of shot gathers to produce dozens of planes waves. A regularization term which penalizes the image difference between nearby angles are used to keep the prestack image consistent through all the angles. Numerical tests on a marine dataset is performed to illustrate the advantages of least-squares reverse time migration in the plane-wave domain. Through iterations of least-squares migration, the migration artifacts are reduced and the image resolution is improved. Empirical results suggest that the LSRTM in plane wave domain is an efficient method to improve the image quality and produce common image gathers.

  10. Sparse least-squares reverse time migration using seislets

    KAUST Repository

    Dutta, Gaurav

    2015-08-19

    We propose sparse least-squares reverse time migration (LSRTM) using seislets as a basis for the reflectivity distribution. This basis is used along with a dip-constrained preconditioner that emphasizes image updates only along prominent dips during the iterations. These dips can be estimated from the standard migration image or from the gradient using plane-wave destruction filters or structural tensors. Numerical tests on synthetic datasets demonstrate the benefits of this method for mitigation of aliasing artifacts and crosstalk noise in multisource least-squares migration.

  11. Migration and first-time parenthood: Evidence from Kyrgyzstan

    Directory of Open Access Journals (Sweden)

    Gunnar Andersson

    2007-12-01

    Full Text Available This article investigates the reproductive behavior of young women and men in the post-Soviet Central Asian republic of Kyrgyzstan, focusing on the link between migration and fertility. We employ event-history techniques to retrospective data from the 'Marriage, Fertility, and Migration' survey conducted in Northern Kyrgyzstan in 2005 to study patterns in first-time parenthood. We demonstrate the extent to which internal migration is related to family formation and to the patterns of becoming a parent after resettlement. We gain deeper insights into demographic behavior by considering information on factors such as the geographical destination of migration and retrospectively stated motives for reported moves. In addition, our study reveals clear ethno-cultural differences in the timing of entry into parenthood in Kyrgyzstan.

  12. Electrical guidance efficiency of downstream-migrating juvenile Sea Lamprey decreases with increasing water velocity

    Science.gov (United States)

    Miehls, Scott M.; Johnson, Nicholas; Haro, Alexander

    2017-01-01

    We tested the efficacy of a vertically oriented field of pulsed direct current (VEPDC) created by an array of vertical electrodes for guiding downstream-moving juvenile Sea Lampreys Petromyzon marinus to a bypass channel in an artificial flume at water velocities of 10–50 cm/s. Sea Lampreys were more likely to be captured in the bypass channel than in other sections of the flume regardless of electric field status (on or off) or water velocity. Additionally, Sea Lampreys were more likely to be captured in the bypass channel when the VEPDC was active; however, an interaction between the effects of VEPDC and water velocity was observed, as the likelihood of capture decreased with increases in water velocity. The distribution of Sea Lampreys shifted from right to left across the width of the flume toward the bypass channel when the VEPDC was active at water velocities less than 25 cm/s. The VEPDC appeared to have no effect on Sea Lamprey distribution in the flume at water velocities greater than 25 cm/s. We also conducted separate tests to determine the threshold at which Sea Lampreys would become paralyzed. Individuals were paralyzed at a mean power density of 37.0 µW/cm3. Future research should investigate the ability of juvenile Sea Lampreys to detect electric fields and their specific behavioral responses to electric field characteristics so as to optimize the use of this technology as a nonphysical guidance tool across variable water velocities.

  13. Anisotropy signature in extended images from reverse-time migration

    KAUST Repository

    Sava, Paul

    2012-11-04

    Reverse-time migration can accurately image complex geologic structures in anisotropic media. Extended images at selected locations in the earth, i.e. at common-image-point gathers (CIPs), carry enough information to characterize the angle-dependent illumination and to provide measurements for migration velocity analysis. Furthermore, inaccurate anisotropy leaves a distinctive signature in CIPs, which can be used to evaluate anisotropy through techniques similar to the ones used in conventional wavefield tomography.

  14. Anisotropy signature in extended images from reverse-time migration

    KAUST Repository

    Sava, Paul; Alkhalifah, Tariq Ali

    2012-01-01

    Reverse-time migration can accurately image complex geologic structures in anisotropic media. Extended images at selected locations in the earth, i.e. at common-image-point gathers (CIPs), carry enough information to characterize the angle-dependent illumination and to provide measurements for migration velocity analysis. Furthermore, inaccurate anisotropy leaves a distinctive signature in CIPs, which can be used to evaluate anisotropy through techniques similar to the ones used in conventional wavefield tomography.

  15. Thinking like a duck: fall lake use and movement patterns of juvenile ring-necked ducks before migration.

    Science.gov (United States)

    Roy, Charlotte L; Fieberg, John; Scharenbroich, Christopher; Herwig, Christine M

    2014-01-01

    The post-fledging period is one of the least studied portions of the annual cycle in waterfowl. Yet, recruitment into the breeding population requires that young birds have sufficient resources to survive this period. We used radio-telemetry and generalized estimating equations to examine support for four hypotheses regarding the drivers of landscape scale habitat use and movements made by juvenile ring-necked ducks between the pre-fledging period and departure for migration. Our response variables included the probability of movement, distances moved, and use of different lake types: brood-rearing lakes, staging lakes, and lakes with low potential for disturbance. Birds increased their use of staging areas and lakes with low potential for disturbance (i.e., without houses or boat accesses, >100 m from roads, or big lakes with areas where birds could sit undisturbed) throughout the fall, but these changes began before the start of the hunting season and their trajectory was not changed by the onset of hunting. Males and females moved similar distances and had similar probabilities of movements each week. However, females were more likely than males to use brood-rearing lakes later in the fall. Our findings suggest juvenile ring-necked ducks require different lake types throughout the fall, and managing solely for breeding habitat will be insufficient for meeting needs during the post-fledging period. Maintaining areas with low potential for disturbance and areas suitable for staging will ensure that ring-necked ducks have access to habitat throughout the fall.

  16. Least-squares reverse time migration of multiples

    KAUST Repository

    Zhang, Dongliang

    2013-12-06

    The theory of least-squares reverse time migration of multiples (RTMM) is presented. In this method, least squares migration (LSM) is used to image free-surface multiples where the recorded traces are used as the time histories of the virtual sources at the hydrophones and the surface-related multiples are the observed data. For a single source, the entire free-surface becomes an extended virtual source where the downgoing free-surface multiples more fully illuminate the subsurface compared to the primaries. Since each recorded trace is treated as the time history of a virtual source, knowledge of the source wavelet is not required and the ringy time series for each source is automatically deconvolved. If the multiples can be perfectly separated from the primaries, numerical tests on synthetic data for the Sigsbee2B and Marmousi2 models show that least-squares reverse time migration of multiples (LSRTMM) can significantly improve the image quality compared to RTMM or standard reverse time migration (RTM) of primaries. However, if there is imperfect separation and the multiples are strongly interfering with the primaries then LSRTMM images show no significant advantage over the primary migration images. In some cases, they can be of worse quality. Applying LSRTMM to Gulf of Mexico data shows higher signal-to-noise imaging of the salt bottom and top compared to standard RTM images. This is likely attributed to the fact that the target body is just below the sea bed so that the deep water multiples do not have strong interference with the primaries. Migrating a sparsely sampled version of the Marmousi2 ocean bottom seismic data shows that LSM of primaries and LSRTMM provides significantly better imaging than standard RTM. A potential liability of LSRTMM is that multiples require several round trips between the reflector and the free surface, so that high frequencies in the multiples suffer greater attenuation compared to the primary reflections. This can lead to lower

  17. Reverse time migration of prism waves for salt flank delineation

    KAUST Repository

    Dai, Wei; Schuster, Gerard T.

    2013-01-01

    In this paper, we present a new reverse time migration method for imaging salt flanks with prism wave reflections. It consists of four steps: (1) migrating the seismic data with conventional RTM to give the RTM image; (2) using the RTM image as a reflectivity model to simulate source-side reflections with the Born approximation; (3) zero-lag correlation of the source-side reflection wavefields and receiver-side wavefields to produce the prism wave migration image; and (4) repeating steps 2 and 3 for the receiver-side reflections. An advantage of this method is that there is no need to pick the horizontal reflectors prior to migration of the prism waves. It also separately images the vertical structures at a different step to reduce crosstalk interference. The disadvantage of prism wave migration algorithm is that its computational cost is twice that of conventional RTM. The empirical results with a salt model suggest that prism wave migration can be an effective method for salt flank delineation in the absence of diving waves.

  18. Reverse time migration of prism waves for salt flank delineation

    KAUST Repository

    Dai, Wei

    2013-09-22

    In this paper, we present a new reverse time migration method for imaging salt flanks with prism wave reflections. It consists of four steps: (1) migrating the seismic data with conventional RTM to give the RTM image; (2) using the RTM image as a reflectivity model to simulate source-side reflections with the Born approximation; (3) zero-lag correlation of the source-side reflection wavefields and receiver-side wavefields to produce the prism wave migration image; and (4) repeating steps 2 and 3 for the receiver-side reflections. An advantage of this method is that there is no need to pick the horizontal reflectors prior to migration of the prism waves. It also separately images the vertical structures at a different step to reduce crosstalk interference. The disadvantage of prism wave migration algorithm is that its computational cost is twice that of conventional RTM. The empirical results with a salt model suggest that prism wave migration can be an effective method for salt flank delineation in the absence of diving waves.

  19. Coherence measures in automatic time-migration velocity analysis

    International Nuclear Information System (INIS)

    Maciel, Jonathas S; Costa, Jessé C; Schleicher, Jörg

    2012-01-01

    Time-migration velocity analysis can be carried out automatically by evaluating the coherence of migrated seismic events in common-image gathers (CIGs). The performance of gradient methods for automatic time-migration velocity analysis depends on the coherence measures used as the objective function. We compare the results of four different coherence measures, being conventional semblance, differential semblance, an extended differential semblance using differences of more distant image traces and the product of the latter with conventional semblance. In our numerical experiments, the objective functions based on conventional semblance and on the product of conventional semblance with extended differential semblance provided the best velocity models, as evaluated by the flatness of the resulting CIGs. The method can be easily extended to anisotropic media. (paper)

  20. Diel horizontal migration in streams: juvenile fish exploit spatial heterogeneity in thermal and trophic resources

    Science.gov (United States)

    Armstrong, Jonathan B.; Schindler, Daniel E.; Ruff, Casey P.; Brooks, Gabriel T.; Bentley, Kale E.; Torgersen, Christian E.

    2013-01-01

    Vertical heterogeneity in the physical characteristics of lakes and oceans is ecologically salient and exploited by a wide range of taxa through diel vertical migration to enhance their growth and survival. Whether analogous behaviors exploit horizontal habitat heterogeneity in streams is largely unknown. We investigated fish movement behavior at daily timescales to explore how individuals integrated across spatial variation in food abundance and water temperature. Juvenile coho salmon made feeding forays into cold habitats with abundant food, and then moved long distances (350–1300 m) to warmer habitats that accelerated their metabolism and increased their assimilative capacity. This behavioral thermoregulation enabled fish to mitigate trade-offs between trophic and thermal resources by exploiting thermal heterogeneity. Fish that exploited thermal heterogeneity grew at substantially faster rates than did individuals that assumed other behaviors. Our results provide empirical support for the importance of thermal diversity in lotic systems, and emphasize the importance of considering interactions between animal behavior and habitat heterogeneity when managing and restoring ecosystems.

  1. Distribution and Joint Fish-Tag Survival of Juvenile Chinook Salmon Migrating through the Sacramento-San Joaquin River Delta, California, 2008

    Science.gov (United States)

    Holbrook, Christopher M.; Perry, Russell W.; Adams, Noah S.

    2009-01-01

    Acoustic telemetry was used to obtain the movement histories of 915 juvenile fall-run Chinook salmon (Oncorhynchus tshawytscha) through the lower San Joaquin River and Sacramento-San Joaquin Delta, California, in 2008. Data were analyzed within a release-recapture framework to estimate survival, route distribution, and detection probabilities among three migration pathways through the Delta. The pathways included the primary route through the San Joaquin River and two less direct routes (Old River and Turner Cut). Strong inferences about survival were limited by premature tag failure, but estimates of fish distribution among migration routes should be unaffected by tag failure. Based on tag failure tests (N = 66 tags), we estimated that only 55-78 percent of the tags used in this study were still functioning when the last fish was detected exiting the study area 15 days after release. Due to premature tag failure, our 'survival' estimates represent the joint probability that both the tag and fish survived, not just survival of fish. Low estimates of fish-tag survival could have been caused by fish mortality or fish travel times that exceeded the life of the tag, but we were unable to differentiate between the two. Fish-tag survival through the Delta (from Durham Ferry to Chipps Island by all routes) ranged from 0.05 +or- 0.01 (SE) to 0.06 +or- 0.01 between the two weekly release groups. Among the three migration routes, fish that remained in the San Joaquin River exhibited the highest joint fish-tag survival (0.09 +or- 0.02) in both weeks, but only 22-33 percent of tagged fish used this route, depending on the week of release. Only 4-10 percent (depending on week) of tagged fish traveled through Turner Cut, but no tagged fish that used this route were detected exiting the Delta. Most fish (63-68 percent, depending on week of release) migrated through Old River, but fish-tag survival through this route (0.05 +or- 0.01) was only about one-half that of fish that

  2. Synthetic seismic monitoring using reverse-time migration and Kirchhoff migration for CO2 sequestration in Korea

    Science.gov (United States)

    Kim, W.; Kim, Y.; Min, D.; Oh, J.; Huh, C.; Kang, S.

    2012-12-01

    During last two decades, CO2 sequestration in the subsurface has been extensively studied and progressed as a direct tool to reduce CO2 emission. Commercial projects such as Sleipner, In Salah and Weyburn that inject more than one million tons of CO2 per year are operated actively as well as test projects such as Ketzin to study the behavior of CO2 and the monitoring techniques. Korea also began the CCS (CO2 capture and storage) project. One of the prospects for CO2 sequestration in Korea is the southwestern continental margin of Ulleung basin. To monitor the behavior of CO2 underground for the evaluation of stability and safety, several geophysical monitoring techniques should be applied. Among various geophysical monitoring techniques, seismic survey is considered as the most effective tool. To verify CO2 migration in the subsurface more effectively, seismic numerical simulation is an essential process. Furthermore, the efficiency of the seismic migration techniques should be investigated for various cases because numerical seismic simulation and migration test help us accurately interpret CO2 migration. In this study, we apply the reverse-time migration and Kirchhoff migration to synthetic seismic monitoring data generated for the simplified model based on the geological structures of Ulleung basin in Korea. Synthetic seismic monitoring data are generated for various cases of CO2 migration in the subsurface. From the seismic migration images, we can investigate CO2 diffusion patterns indirectly. From seismic monitoring simulation, it is noted that while the reverse-time migration generates clear subsurface images when subsurface structures are steeply dipping, Kirchhoff migration has an advantage in imaging horizontal-layered structures such as depositional sediments appearing in the continental shelf. The reverse-time migration and Kirchhoff migration present reliable subsurface images for the potential site characterized by stratigraphical traps. In case of

  3. 3D pre-stack time migration; Kiruhihoffuho ni yoru sanjigen jugo mae jikan migration shori

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, Y; Matsuoka, T [Japan Petroleum Exploration Corp., Tokyo (Japan); Tsuru, T [Japan National Oil Corp., Tokyo (Japan)

    1997-05-27

    This paper reports pre-stack migration in elastic wave exploration as to its algorithm and examples of processed data. The time migration processing hypothesizes that seismic waves propagate linearly. It calculates travel time by dividing the sum of the straight distance from a vibration transmitting point to an image point and the straight distance from the image point to a vibration receiving point with RMS velocity given as a parameter. To maintain the relative relation of amplitude sizes, the signal on an elliptic body is made smaller in inverse proportion to the size of that elliptic body. With regard to apparent interval of input trace as seen from the reflection surface, or with regard to density, the signal is made smaller by cos{theta} times. While this program deals with three-dimensional migration, its output turns out as an arbitrary two-dimensional plane. The program requires a huge amount of data processing, whereas a method is used, that the input trace is divided, each group is processed by using separate computers, and the results are summed up. 3 refs., 4 figs.

  4. Full Waveform Inversion Using Oriented Time Migration Method

    KAUST Repository

    Zhang, Zhendong

    2016-04-12

    Full waveform inversion (FWI) for reflection events is limited by its linearized update requirements given by a process equivalent to migration. Unless the background velocity model is reasonably accurate the resulting gradient can have an inaccurate update direction leading the inversion to converge into what we refer to as local minima of the objective function. In this thesis, I first look into the subject of full model wavenumber to analysis the root of local minima and suggest the possible ways to avoid this problem. And then I analysis the possibility of recovering the corresponding wavenumber components through the existing inversion and migration algorithms. Migration can be taken as a generalized inversion method which mainly retrieves the high wavenumber part of the model. Conventional impedance inversion method gives a mapping relationship between the migration image (high wavenumber) and model parameters (full wavenumber) and thus provides a possible cascade inversion strategy to retrieve the full wavenumber components from seismic data. In the proposed approach, consider a mild lateral variation in the model, I find an analytical Frechet derivation corresponding to the new objective function. In the proposed approach, the gradient is given by the oriented time-domain imaging method. This is independent of the background velocity. Specifically, I apply the oriented time-domain imaging (which depends on the reflection slope instead of a background velocity) on the data residual to obtain the geometrical features of the velocity perturbation. Assuming that density is constant, the conventional 1D impedance inversion method is also applicable for 2D or 3D velocity inversion within the process of FWI. This method is not only capable of inverting for velocity, but it is also capable of retrieving anisotropic parameters relying on linearized representations of the reflection response. To eliminate the cross-talk artifacts between different parameters, I

  5. Age at migration, family instability, and timing of sexual onset.

    Science.gov (United States)

    Goldberg, Rachel E; Tienda, Marta; Adserà, Alícia

    2017-03-01

    This study builds on and extends previous research on nativity variations in adolescent health and risk behavior by addressing three questions: (1) whether and how generational status and age at migration are associated with timing of sexual onset among U.S. adolescents; (2) whether and how family instability mediates associations between nativity and sexual debut; and (3) whether and how these associations vary by gender. We find that first- and second-generation immigrant youth initiate sexual activity later than native youth. Foreign-born youth who migrate after the start of adolescence exhibit the latest sexual onset; boys' sexual behavior is particularly sensitive to age at migration. Parental union stability is protective for first- and second-generation youth, especially boys; however, instability in co-residence with parents accelerates sexual debut for foreign-born girls, and dilutes protections from parental marital stability. Use of a non-English language at home delays sexual onset for immigrant girls, but not boys. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Dispersal time for ancient human migrations: Americas and Europe colonization

    Science.gov (United States)

    Flores, J. C.

    2007-07-01

    I apply the recently proposed intermittence strategy to investigate the ancient human migrations in the world. That is, the Americas colonization (Bering-bridge and Pacific-coast theories) and Neanderthal replacement in Europe around 45000 years before the present. Using a mathematical equation related to diffusion and ballistic motion, I calculate the colonization time in all these cases in good agreement with archeological data (including Neolithic transition in Europe). Moreover, to support these calculations, I obtain analytically the effective speed of colonization in Europe veff=0.62 [km/yr] and related to the Aurignacian culture propagation.

  7. Reverse time migration of multiples for OBS data

    KAUST Repository

    Zhang, Dongliang

    2014-01-01

    Reverse time migration of multiples (RTMM) is applied to OBS data with sparse receiver spacing. RTMM for OBS data unlike a marine streamer acquisition is implemented in the common receiver gathers (CRG) and provides a wider and denser illumination for each CRG than the conventional RTM of primaries. Hence, while the the conventional RTM image contains strong aliasing artifacts due to a sparser receiver interval, the RTMM image suffers from this artifacts less. This benefit of RTMM is demonstrated with numerical test on the Marmousi model for sparsely sampled OBS data.

  8. Reverse time migration of multiples for OBS data

    KAUST Repository

    Zhang, Dongliang

    2014-08-05

    Reverse time migration of multiples (RTMM) is applied to OBS data with sparse receiver spacing. RTMM for OBS data unlike a marine streamer acquisition is implemented in the common receiver gathers (CRG) and provides a wider and denser illumination for each CRG than the conventional RTM of primaries. Hence, while the the conventional RTM image contains strong aliasing artifacts due to a sparser receiver interval, the RTMM image suffers from this artifacts less. This benefit of RTMM is demonstrated with numerical test on the Marmousi model for sparsely sampled OBS data.

  9. Detection of cavity migration risks using radar interferometric time series

    Science.gov (United States)

    Chang, L.; Hanssen, R. F.

    2012-12-01

    The upward migration of near-surface underground cavities can pose a major hazard for people and infrastructure. Being the major cause of sudden collapse-sinkholes, or causing a sudden lack of support of building foundations, a migrating cavity can cause the collapse of buildings, water defense systems, drainage of water bodies, or transport infrastructure. Cavity migration can occur naturally, e.g. in karst-massifs, but could also be caused by anthropogenic activities such as mining. The chief difficulty in the assessment of sinkhole risk is the lack of prior knowledge on the location of the cavity. Although in situ measurements such as gravimetry, seismic or EM-surveying or GPR are in principle able to detect an underground void, it is generally not economically possible to use these techniques over vast areas. Moreover, the risk of casualties is highest for urbanized areas, in which it is difficult to get close enough to perform these measurements. The second problem is that there is usually no data available prior to the collapse, to understand whether there is for example precursory motion, and how far ahead in time critical levels can be detected. Here we report on the catastrophic collapse of the foundation of an underground parking garage in Heerlen, the Netherlands. In December 2011, some pillars supporting the roof of the garage and the shopping mall above it suddenly subsided more than one meter. This caused the near collapse of a part of the shopping mall, the immediate evacuation of the building, and the decision of the authorities to eliminate the building. In the analysis of the event, several hypotheses were formulated on the driving mechanisms, such as subsurface water flows and karst. However, as the region was subject to coal mining in the last century, alternative hypotheses were cavity migration due to the mining, or rebound of the surface due to mine water. Our study jointly exploits the data archives of four imaging radar satellites, ERS-1

  10. Plane-wave Least-squares Reverse Time Migration

    KAUST Repository

    Dai, Wei; Schuster, Gerard T.

    2012-01-01

    convergence for least-squares migration even when the migration velocity is not completely accurate. To significantly reduce computation cost, linear phase shift encoding is applied to hundreds of shot gathers to produce dozens of planes waves. A

  11. Ultrasound breast imaging using frequency domain reverse time migration

    Science.gov (United States)

    Roy, O.; Zuberi, M. A. H.; Pratt, R. G.; Duric, N.

    2016-04-01

    Conventional ultrasonography reconstruction techniques, such as B-mode, are based on a simple wave propagation model derived from a high frequency approximation. Therefore, to minimize model mismatch, the central frequency of the input pulse is typically chosen between 3 and 15 megahertz. Despite the increase in theoretical resolution, operating at higher frequencies comes at the cost of lower signal-to-noise ratio. This ultimately degrades the image contrast and overall quality at higher imaging depths. To address this issue, we investigate a reflection imaging technique, known as reverse time migration, which uses a more accurate propagation model for reconstruction. We present preliminary simulation results as well as physical phantom image reconstructions obtained using data acquired with a breast imaging ultrasound tomography prototype. The original reconstructions are filtered to remove low-wavenumber artifacts that arise due to the inclusion of the direct arrivals. We demonstrate the advantage of using an accurate sound speed model in the reverse time migration process. We also explain how the increase in computational complexity can be mitigated using a frequency domain approach and a parallel computing platform.

  12. Anisotropy signature in reverse-time migration extended images

    KAUST Repository

    Sava, Paul C.; Alkhalifah, Tariq Ali

    2014-01-01

    Reverse-time migration can accurately image complex geologic structures in anisotropic media. Extended images at selected locations in the Earth, i.e., at common-image-point gathers, carry rich information to characterize the angle-dependent illumination and to provide measurements for migration velocity analysis. However, characterizing the anisotropy influence on such extended images is a challenge. Extended common-image-point gathers are cheap to evaluate since they sample the image at sparse locations indicated by the presence of strong reflectors. Such gathers are also sensitive to velocity error that manifests itself through moveout as a function of space and time lags. Furthermore, inaccurate anisotropy leaves a distinctive signature in common-image-point gathers, which can be used to evaluate anisotropy through techniques similar to the ones used in conventional wavefield tomography. It specifically admits a V-shaped residual moveout with the slope of the "V" flanks depending on the anisotropic parameter η regardless of the complexity of the velocity model. It reflects the fourth-order nature of the anisotropy influence on moveout as it manifests itself in this distinct signature in extended images after handling the velocity properly in the imaging process. Synthetic and real data observations support this assertion.

  13. Anisotropy signature in reverse-time migration extended images

    KAUST Repository

    Sava, Paul C.

    2014-11-04

    Reverse-time migration can accurately image complex geologic structures in anisotropic media. Extended images at selected locations in the Earth, i.e., at common-image-point gathers, carry rich information to characterize the angle-dependent illumination and to provide measurements for migration velocity analysis. However, characterizing the anisotropy influence on such extended images is a challenge. Extended common-image-point gathers are cheap to evaluate since they sample the image at sparse locations indicated by the presence of strong reflectors. Such gathers are also sensitive to velocity error that manifests itself through moveout as a function of space and time lags. Furthermore, inaccurate anisotropy leaves a distinctive signature in common-image-point gathers, which can be used to evaluate anisotropy through techniques similar to the ones used in conventional wavefield tomography. It specifically admits a V-shaped residual moveout with the slope of the "V" flanks depending on the anisotropic parameter η regardless of the complexity of the velocity model. It reflects the fourth-order nature of the anisotropy influence on moveout as it manifests itself in this distinct signature in extended images after handling the velocity properly in the imaging process. Synthetic and real data observations support this assertion.

  14. Migrational Characteristics, Biological Observations, and Relative Survival of Juvenile Salmonids Entering the Columbia River Estuary, 1966-1983, 1985 Final Report of Research.

    Energy Technology Data Exchange (ETDEWEB)

    Dawley, Earl M.

    1986-04-01

    Natural runs of salmonids in the Columbia River basin have decreased as a result of hydroelectric-dam development, poor land- and forest-management, and over-fishing. This has necessitated increased salmon culture to assure adequate numbers of returning adults. Hatchery procedures and facilities are continually being modified to improve both the efficiency of production and the quality of juveniles produced. Initial efforts to evaluate changes in hatchery procedures were dependent upon adult contributions to the fishery and returns to the hatchery. Procedures were developed for sampling juvenile salmon and steelhead entering the Columbia River estuary and ocean plume. The sampling of hatchery fish at the terminus of their freshwater migration assisted in evaluating hatchery production techniques and identifying migrational or behavioral characteristics that influence survival to and through the estuary. The sampling program attempted to estimate survival of different stocks and define various aspects of migratory behavior in a large river, with flows during the spring freshet from 4 to 17 thousand cubic meters per second (m/sup 3//second).

  15. Attenuation compensation in least-squares reverse time migration using the visco-acoustic wave equation

    KAUST Repository

    Dutta, Gaurav; Lu, Kai; Wang, Xin; Schuster, Gerard T.

    2013-01-01

    Attenuation leads to distortion of amplitude and phase of seismic waves propagating inside the earth. Conventional acoustic and least-squares reverse time migration do not account for this distortion which leads to defocusing of migration images

  16. A comparison of single-suture and double-suture incision closures in seaward-migrating juvenile Chinook salmon implanted with acoustic transmitters: implications for research in river basins containing hydropower structures

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Richard S.; Deters, Katherine A.; Cook, Katrina V.; Eppard, M. B.

    2013-07-15

    Reductions in the size of acoustic transmitters implanted in migrating juvenile salmonids have resulted in the ability to make shorter incisions that may warrant using only a single suture for closure. However, it is not known if one suture will sufficiently hold the incision closed, particularly when outward pressure is placed on the surgical site such as when migrating fish experience pressure changes associated with passage at hydroelectric dams. The objective of this research was to evaluate the effectiveness of single-suture incision closures on juvenile Chinook salmon (Oncorhynchus tshawytscha). Juvenile Chinook salmon were surgically implanted with a 2012 Juvenile Salmon Acoustic Telemetry System (JSATS) transmitter (0.30 g) and a passive integrated transponder tag (0.10 g) and incisions were closed with either one suture or two sutures. Mortality and tag retention were monitored and fish were examined after 7 and 14 days to evaluate tissue responses. In a separate experiment, surgically implanted fish were exposed to simulated turbine passage and then examined for expulsion of transmitters, expulsion of viscera through the incision, and mortal injury. With incisions closed using a single suture, there was no mortality or tag loss and similar or reduced tissue reaction compared to incisions closed with two sutures. Further, surgery time was significantly reduced when one suture was used, which leads to less handling and reduced stress. No tags were expelled during pressure scenarios and expulsion of viscera only occurred in two non-mortally injured fish (5%) with single sutures that were also exposed to very high pressure changes. No viscera expulsion was present in fish exposed to pressure scenarios likely representative of hydroturbine passage at many Columbia River dams (e.g. <2.7 ratio of pressure change; an acclimation pressure of 146.2 absolute kpa and a lowest exposure pressure of ~ 53.3 absolute kpa). Based on these results, we recommend the use of a

  17. Modified interferometric imaging condition for reverse-time migration

    Science.gov (United States)

    Guo, Xue-Bao; Liu, Hong; Shi, Ying

    2018-01-01

    For reverse-time migration, high-resolution imaging mainly depends on the accuracy of the velocity model and the imaging condition. In practice, however, the small-scale components of the velocity model cannot be estimated by tomographical methods; therefore, the wavefields are not accurately reconstructed from the background velocity, and the imaging process will generate artefacts. Some of the noise is due to cross-correlation of unrelated seismic events. Interferometric imaging condition suppresses imaging noise very effectively, especially the unknown random disturbance of the small-scale part. The conventional interferometric imaging condition is extended in this study to obtain a new imaging condition based on the pseudo-Wigner distribution function (WDF). Numerical examples show that the modified interferometric imaging condition improves imaging precision.

  18. Magnetotelluric inversion via reverse time migration algorithm of seismic data

    International Nuclear Information System (INIS)

    Ha, Taeyoung; Shin, Changsoo

    2007-01-01

    We propose a new algorithm for two-dimensional magnetotelluric (MT) inversion. Our algorithm is an MT inversion based on the steepest descent method, borrowed from the backpropagation technique of seismic inversion or reverse time migration, introduced in the middle 1980s by Lailly and Tarantola. The steepest descent direction can be calculated efficiently by using the symmetry of numerical Green's function derived from a mixed finite element method proposed by Nedelec for Maxwell's equation, without calculating the Jacobian matrix explicitly. We construct three different objective functions by taking the logarithm of the complex apparent resistivity as introduced in the recent waveform inversion algorithm by Shin and Min. These objective functions can be naturally separated into amplitude inversion, phase inversion and simultaneous inversion. We demonstrate our algorithm by showing three inversion results for synthetic data

  19. Least-squares reverse time migration with radon preconditioning

    KAUST Repository

    Dutta, Gaurav

    2016-09-06

    We present a least-squares reverse time migration (LSRTM) method using Radon preconditioning to regularize noisy or severely undersampled data. A high resolution local radon transform is used as a change of basis for the reflectivity and sparseness constraints are applied to the inverted reflectivity in the transform domain. This reflects the prior that for each location of the subsurface the number of geological dips is limited. The forward and the adjoint mapping of the reflectivity to the local Radon domain and back are done through 3D Fourier-based discrete Radon transform operators. The sparseness is enforced by applying weights to the Radon domain components which either vary with the amplitudes of the local dips or are thresholded at given quantiles. Numerical tests on synthetic and field data validate the effectiveness of the proposed approach in producing images with improved SNR and reduced aliasing artifacts when compared with standard RTM or LSRTM.

  20. INFLUENCE OF FEEDING TIME ON FEED UTILIZATION BY SIAMESE CATFISH, Pangasius hypophthalmus JUVENILE

    Directory of Open Access Journals (Sweden)

    Nina Meilisza

    2010-06-01

    Full Text Available Siamese catfish (Pangasius hypophthalmus at juvenile stage is used as ornamental fish by fish hobbies because of their beautiful shape and movement. Feeding time is a part of feeding management to get the best and effective strategy on feed input. This study aimed to determine the growth of Siamese catfish juvenile by looking at the influence of feeding time on feed utilization. The average individual weight of juveniles used was ± 3.2 g stocked 15 fish per aquarium equipped with recirculation system. Two level factors in the factorial design consisted of 4 feeding times (at 8:00, at 12:00, at 16:00, and as control (8:00, 12:00, 16:00 and feeding level (45 g feed kg-1 fish, 90 g feed kg-1 fish. Interaction between feeding time and feeding level resulting eight types of treatments research, namely A (8/45, B (12/45, C (16/45, D (8:12:16/45, E (8:12:16/90, F (8/90, G (12/90, and H (16/90. The results showed that feeding time had significant effect on the specific growth rate, feed conversion, and protein efficiency ratio and were significantly different among the treatments (P<0.05. Besides feeding time control (treatments D and E, treatment C also showed the highest of specific growth rate (2.03%, protein efficiency ratio (1.46, and the lowest feed conversion ratio (1.85.

  1. Spatial segregation within the spawning migration of North Eastern Atlantic mackerel (Scomber scombrus) as indicated by juvenile growth patterns

    DEFF Research Database (Denmark)

    Jansen, Teunis; Campbell, Andrew; Brunel, Thomas

    2013-01-01

    A comparison of growth data (fish length) with latitude shows that southern juvenile mackerel attain a greater length than those originating from further north before growth ceases during their first winter. A similar significant relationship was found between the growth in the first year (derive...

  2. Effects of zebra mussels on food webs: Interactions with juvenile bluegill and water residence time

    Science.gov (United States)

    Richardson, W.B.; Bartsch, L.A.

    1997-01-01

    We evaluated how water residence time mediated the impact of zebra mussels Dreissena polymorpha and bluegill sunfish Lepomis macrochirus on experimental food webs established in 1100-1 outdoor mesocosms. Water residence time was manipulated as a surrogate for seston resupply - a critical variable affecting growth and survival of suspension-feeding invertebrates. We used a 2 x 2 x 2 factorial experimental design with eight treatment combinations (3 replicates/treatment) including the presence or absence of Dreissena (2000 per m2), juvenile bluegill (40 per mesocosm), and short (1100 1 per d) or long (220 1 per d) water residence time. Measures of seston concentration (chlorophyll a, turbidity and suspended solids) were greater in the short- compared to long water-residence mesocosms, but intermediate in short water-residence mesocosms containing Dreissena. Abundance of rotifers (Keratella and Polyarthra) was reduced in Dreissena mesocosms and elevated in short residence time mesocosms. Cladocera abundance, in general, was unaffected by the presence of Dreissena; densities were higher in short-residence time mesocosms, and reduced in the presence of Lepomis. The growth of juvenile Lepomis were unaffected by Dreissena because of abundant benthic food. The final total mass of Dreissena was significantly greater in short- than long-residence mesocosms. Impacts of Dreissena on planktonic food webs may not only depend on the density of zebra mussels but also on the residence time of the surrounding water and the resupply of seston. ?? 1997 Kluwer Academic Publishers.

  3. Design and Analysis of Salmonid Tagging Studies in the Columbia Basin : Evaluating Wetland Restoration Projects in the Columbia River Estuary using Hydroacoustic Telemetry Arrays to Estimate Movement, Survival, and Residence Times of Juvenile Salmonids, Volume XXII (22).

    Energy Technology Data Exchange (ETDEWEB)

    Perry, Russell W.; Skalski, John R.

    2008-08-01

    Wetlands in the Columbia River estuary are actively being restored by reconnecting these habitats to the estuary, making more wetland habitats available to rearing and migrating juvenile salmon. Concurrently, thousands of acoustically tagged juvenile salmonids are released into the Columbia River to estimate their survival as they migrate through the estuary. Here, we develop a release-recapture model that makes use of these tagged fish to measure the success of wetland restoration projects in terms of their contribution to populations of juvenile salmon. Specifically, our model estimates the fraction of the population that enter the wetland, survival within the wetland, and the mean residence time of fish within the wetland. Furthermore, survival in mainstem Columbia River downstream of the wetland can be compared between fish that remained the mainstem and entered the wetland. These conditional survival estimates provide a means of testing whether the wetland improves the subsequent survival of juvenile salmon by fostering growth or improving their condition. Implementing such a study requires little additional cost because it takes advantage of fish already released to estimate survival through the estuary. Thus, such a study extracts the maximum information at minimum cost from research projects that typically cost millions of dollars annually.

  4. Migration background and juvenile mental health: a descriptive retrospective analysis of diagnostic rates of psychiatric disorders in young people

    Directory of Open Access Journals (Sweden)

    Tilman Jakob Gaber

    2013-06-01

    Full Text Available Introduction: This article presents diagnostic rates for specific mental disorders in a German pediatric inpatient population over a period of 20 years with respect to migration background and socioeconomic status (SES. Methods: Diagnostic data were obtained over a period of 20 years from 8,904 patients who visited a child and adolescent psychiatry mental health service in Germany. Data from 5,985 diagnosed patients (ICD-9 and ICD-10 criteria were included with respect to gender, migration background, and SES. Results:Migration- and gender-specific effects were found for both periods of assessment. The group of boys with a migration background showed significantly higher rates of reactions to severe stress, adjustment disorders, and posttraumatic stress disorder compared to their male, non-migrant counterparts. Conversely, boys without a migration background showed a significantly higher percentage rate of hyperkinetic disorders than male migrants. Similar results were found for female migrants in the latter assessment period (ICD-10. In addition, female migrants showed lower rates of emotional disorders whose onset occurs in childhood compared to their non-migrant counterparts. Conclusions: Data from this investigation provide preliminary evidence that the prevalence of various psychiatric disorders in children and adolescents is influenced by migration background and SES.

  5. Sparse least-squares reverse time migration using seislets

    KAUST Repository

    Dutta, Gaurav; Schuster, Gerard T.

    2015-01-01

    the iterations. These dips can be estimated from the standard migration image or from the gradient using plane-wave destruction filters or structural tensors. Numerical tests on synthetic datasets demonstrate the benefits of this method for mitigation of aliasing

  6. Full Waveform Inversion Using Oriented Time Migration Method

    KAUST Repository

    Zhang, Zhendong

    2016-01-01

    Full waveform inversion (FWI) for reflection events is limited by its linearized update requirements given by a process equivalent to migration. Unless the background velocity model is reasonably accurate the resulting gradient can have

  7. Effects of salinity on gastric emptying time in hybrid grouper, Epinephelus fuscoguttatus x E. lanceolattus juveniles

    Science.gov (United States)

    Noor, Noorashikin Md.; Das, Simon Kumar; Cob, Zaidi Che; Ghaffar, Mazlan Abd.

    2018-04-01

    The newly developed hybrid grouper: tiger grouper (Epinephelus fuscoguttatus) × giant grouper (Epinephelus fuscoguttatus) (TG×GG), has a high resistance towards different environmental condition (eg. in euryhaline environment) due to its genetic improvement. This study aims to investigate the effects of different salinities (10, 15, 20, 25 and 30 ppt) on the gastric emptying time (GET) of the TG×GG hybrid grouper juveniles. The fish were fed with commercial pellet over a 30 days experimental period under controlled laboratory conditions. The GET was determined by X-radiographic method, using barium sulfate (BaSO4) as an inert food marker. The X-radiography images showed that the shortest GET (12 h) was observed in the 15 ppt group, whereas the longest GET (18 h) in 30 ppt group. The results suggests to culture TG×GG hybrid grouper juveniles in 15 ppt with commercial pellet diet as this salinity proliferates faster digestion process which may contribute faster growth rate of this important fish species. Overall, these findings would be useful for the betterment of TG×GG hybrid grouper aquaculture which will eventually boost up the production of this newly developed hybrid grouper species.

  8. Attenuation compensation in least-squares reverse time migration using the visco-acoustic wave equation

    KAUST Repository

    Dutta, Gaurav

    2013-08-20

    Attenuation leads to distortion of amplitude and phase of seismic waves propagating inside the earth. Conventional acoustic and least-squares reverse time migration do not account for this distortion which leads to defocusing of migration images in highly attenuative geological environments. To account for this distortion, we propose to use the visco-acoustic wave equation for least-squares reverse time migration. Numerical tests on synthetic data show that least-squares reverse time migration with the visco-acoustic wave equation corrects for this distortion and produces images with better balanced amplitudes compared to the conventional approach. © 2013 SEG.

  9. Migration aspirations of European youth in times of crisis

    NARCIS (Netherlands)

    Van Mol, C.

    2016-01-01

    In recent years, the European Union (EU) passed through a significant economic crisis. All across Europe, European young people are among the groups which are hit hardest, with youth unemployment rates rising to over 50% in member states such as Greece and Spain. In the classical migration

  10. Plane-wave least-squares reverse-time migration

    KAUST Repository

    Dai, Wei; Schuster, Gerard T.

    2013-01-01

    . The merits of plane-wave prestack LSRTM are the following: (1) plane-wave prestack LSRTM can sometimes offer stable convergence even when the migration velocity has bulk errors of up to 5%; (2) to significantly reduce computation cost, linear phase

  11. Timing of natal nests is an important factor affecting return rates of juvenile Great Reed Warblers

    Czech Academy of Sciences Publication Activity Database

    Sosnovcová, Kateřina; Koleček, Jaroslav; Požgayová, Milica; Jelínek, Václav; Šulc, Michal; Steidlová, Petra; Honza, Marcel; Procházka, Petr

    2018-01-01

    Roč. 159, č. 1 (2018), s. 183-190 ISSN 0021-8375 R&D Projects: GA ČR GA13-06451S Institutional support: RVO:68081766 Keywords : Acrocephalus arundinaceus * Juvenile condition * Juvenile survival * Local dispersal distances * Natal philopatry Subject RIV: EG - Zoology OBOR OECD: Ornithology Impact factor: 1.468, year: 2016

  12. Migrating to a real-time distributed parallel simulator architecture- An update

    CSIR Research Space (South Africa)

    Duvenhage, B

    2007-09-01

    Full Text Available A legacy non-distributed logical time simulator was previously migrated to a distributed architecture to parallelise execution. The existing Discrete Time System Specification (DTSS) modelling formalism was retained to simplify the reuse of existing...

  13. Cross-continental patterns in the timing of southward Peregrine Falcon migration in North America

    NARCIS (Netherlands)

    Worcester, R.; Ydenberg, R.C.

    2008-01-01

    We analyzed the timing of southward migration of Peregrine Falcons (Falco peregrinus) across North America, based on passage data compiled by the Hawk Migration Association of North America, supplemented with two other similar datasets collected by individual observers at sites in western Canada.

  14. 3D Multi‐source Least‐squares Reverse Time Migration

    KAUST Repository

    Dai, Wei; Boonyasiriwat, Chaiwoot; Schuster, Gerard T.

    2010-01-01

    : random time shift, random source polarity and random source location selected from a pre‐designed table. Numerical tests for the 3D SEG/EAGE Overthrust model show that multi‐source LSRTM can suppress migration artifacts in the migration image and remove

  15. Assessing fish predation on migrating juvenile steelhead and a retrospective comparison to steelhead survival through the Priest Rapids Hydroelectric Project, Columbia River, Washington, 2009-11

    Science.gov (United States)

    Hardiman, Jill M.; Counihan, Timothy D.; Burgess, Dave S.; Simmons, Katrina E.; Holmberg, Glen S.; Rogala, Josh; Polacek, Rochelle

    2012-01-01

    The U.S. Geological Survey (USGS) and the Washington Department of Fish and Wildlife (WDFW) have been working with the Public Utility District No. 2 of Grant County, Washington (Grant PUD), to increase their understanding of predator-prey interactions in the Priest Rapids Hydroelectric Project (PRP), Columbia River, Washington. For this study, the PRP is defined as the area approximately 6 kilometers upstream of Wanapum Dam to the Priest Rapids Dam tailrace, 397.1 miles from the mouth of the Columbia River. Past year’s low survival numbers of juvenile steelhead (Oncorhynchus mykiss) through Wanapum and Priest Rapids Dams has prompted Grant PUD, on behalf of the Priest Rapids Coordinating Committee, to focus research efforts on steelhead migration and potential causal mechanisms for low survival. Steelhead passage survival in 2009 was estimated at 0.944 through the Wanapum Development (dam and reservoir) and 0.881 through the Priest Rapids Development and for 2010, steelhead survival was 0.855 for Wanapum Development and 0.904 for Priest Rapids Development. The USGS and WDFW implemented field collection efforts in 2011 for northern pikeminnow (Ptychocheilus oregonensis), smallmouth bass (Micropterus dolomieu), and walleye (Sander vitreus, formerly Stizostedion vitreum) and their diets in the PRP. For predator indexing, we collected 948 northern pikeminnow, 237 smallmouth bass, 18 walleye, and two largemouth bass (Micropterus salmoides). The intent of this study was to provide standardized predation indices within individual reaches of the PRP to discern spatial variability in predation patterns. Furthermore, the results of the 2011 study were compared to results of a concurrent steelhead survival study. Our results do not indicate excessively high predation of Oncorhynchus spp. occurring by northern pikeminnow or smallmouth bass in any particular reach throughout the study area. Although we found Oncorhynchus spp. in the predator diets, the relative

  16. Time to treatment as an important factor for the response to methotrexate in juvenile idiopathic arthritis.

    Science.gov (United States)

    Albers, H M; Wessels, J A M; van der Straaten, R J H M; Brinkman, D M C; Suijlekom-Smit, L W A; Kamphuis, S S M; Girschick, H J; Wouters, C; Schilham, M W; le Cessie, S; Huizinga, T W J; Ten Cate, R; Guchelaar, H J

    2009-01-15

    Methotrexate (MTX) is the most commonly used disease-modifying antirheumatic drug in juvenile idiopathic arthritis (JIA). Currently, individual response to MTX cannot be reliably predicted. Identification of clinical and genetic factors that influence the response to MTX could be helpful in realizing the optimal treatment for individual patients. A cohort of 128 JIA patients treated with MTX were studied retrospectively. Eleven clinical parameters and genotypes of 6 single nucleotide polymorphisms in 5 genes related to the mechanism of action of MTX were compared between MTX responders and nonresponders using a multivariate regression analysis. The time from diagnosis to start of MTX treatment, physician's global assessment at baseline, and the starting dose were significantly associated with the response to MTX at 6 months after initiation. Patients with a shorter time from diagnosis to start of MTX and a higher disease activity according to the physician but with a lower MTX dose showed an increased response. The effect of the starting dose on MTX response seemed to be mainly due to the influence of the systemic JIA subtype. The time from diagnosis to start of MTX treatment and physician's global assessment at baseline were highly correlated. Therefore, the precise effect size of each independent variable could not be determined. In children with JIA, the time from diagnosis to start of MTX appears to be an important factor for MTX response. Our results suggest that an earlier start of MTX treatment will lead to an increased response.

  17. Time trends in recurrence of juvenile nasopharyngeal angiofibroma: Experience of the past 4 decades.

    Science.gov (United States)

    Mishra, Anupam; Mishra, Subhash Chandra

    2016-01-01

    An analysis of time distribution of juvenile nasopharyngeal angiofibroma (JNA) from the last 4 decades is presented. Sixty recurrences were analyzed as per actuarial survival. SPSS software was used to generate Kaplan-Meier (KM) curves and time distributions were compared by Log-rank, Breslow and Tarone-Ware test. The overall recurrence rate was 17.59%. Majority underwent open transpalatal approach(es) without embolization. The probability of detecting a recurrence was 95% in first 24months and comparison of KM curves of 4 different time periods was not significant. This is the first and largest series to address the time-distribution. The required follow up period is 2years. Our recurrence is just half of the largest series (reported so far) suggesting the superiority of transpalatal techniques. The similarity of curves suggests less likelihood for recent technical advances to influence the recurrence that as per our hypothesis is more likely to reflect tumor biology per se. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Readout electronics of Spes III migration chambers. Nevis migration time coding system

    International Nuclear Information System (INIS)

    Aslanides, E.; Bergdolt, A.M.; Bergdolt, G.; Ernwein, R.; Fassnacht, P.; Guterl, P.; Hibou, F.

    1985-01-01

    Time coder is presented: it digitizes the time intervals between the successive signals from 8 entrance ways and triggering entrance. The Encoder module is aimed at reading and processing the data registered by the time coders. The associated modules are presented (oscillator-clock distributor-test signal distributor) [fr

  19. Remote real-time monitoring of subsurface landfill gas migration.

    Science.gov (United States)

    Fay, Cormac; Doherty, Aiden R; Beirne, Stephen; Collins, Fiachra; Foley, Colum; Healy, John; Kiernan, Breda M; Lee, Hyowon; Maher, Damien; Orpen, Dylan; Phelan, Thomas; Qiu, Zhengwei; Zhang, Kirk; Gurrin, Cathal; Corcoran, Brian; O'Connor, Noel E; Smeaton, Alan F; Diamond, Dermot

    2011-01-01

    The cost of monitoring greenhouse gas emissions from landfill sites is of major concern for regulatory authorities. The current monitoring procedure is recognised as labour intensive, requiring agency inspectors to physically travel to perimeter borehole wells in rough terrain and manually measure gas concentration levels with expensive hand-held instrumentation. In this article we present a cost-effective and efficient system for remotely monitoring landfill subsurface migration of methane and carbon dioxide concentration levels. Based purely on an autonomous sensing architecture, the proposed sensing platform was capable of performing complex analytical measurements in situ and successfully communicating the data remotely to a cloud database. A web tool was developed to present the sensed data to relevant stakeholders. We report our experiences in deploying such an approach in the field over a period of approximately 16 months.

  20. Changes in timing of autumn migration in North European songbird populations

    DEFF Research Database (Denmark)

    Tøttrup, Anders Peter; Thorup, Kasper; Rahbek, Carsten

    2006-01-01

    Although studies of changes in the timing of passerine spring migration are numerous, less is known about timing of their autumn departure. We present phenological data on 22 species based on mist-netted birds caught on the Baltic island of Christiansø during autumn migration between 1976 and 1997...... departure (-0.0426 days year-1, P = 0.40). Testing the 12 species for which the entire migration period was included (thus excluding many long-distance migrants), we found an overall earlier departure (-0.18 days year-1, P = 0.007). Short-distance migrants tended to show earlier departure, while long...

  1. Least-squares reverse time migration of marine data with frequency-selection encoding

    KAUST Repository

    Dai, Wei; Huang, Yunsong; Schuster, Gerard T.

    2013-01-01

    The phase-encoding technique can sometimes increase the efficiency of the least-squares reverse time migration (LSRTM) by more than one order of magnitude. However, traditional random encoding functions require all the encoded shots to share

  2. Common-image gathers in the offset domain from reverse-time migration

    KAUST Repository

    Zhan, Ge

    2014-04-01

    Kirchhoff migration is flexible to output common-image gathers (CIGs) in the offset domain by imaging data with different offsets separately. These CIGs supply important information for velocity model updates and amplitude-variation-with-offset (AVO) analysis. Reverse-time migration (RTM) offers more insights into complex geology than Kirchhoff migration by accurately describing wave propagation using the two-way wave equation. But, it has difficulty to produce offset domain CIGs like Kirchhoff migration. In this paper, we develop a method for obtaining offset domain CIGs from RTM. The method first computes the RTM operator of an offset gather, followed by a dot product of the operator and the offset data to form a common-offset RTM image. The offset domain CIGs are then achieved after separately migrating data with different offsets. We generate offset domain CIGs on both the Marmousi synthetic data and 2D Gulf of Mexico real data using this approach. © 2014.

  3. Seismic time-lapse imaging using Interferometric least-squares migration

    KAUST Repository

    Sinha, Mrinal

    2016-09-06

    One of the problems with 4D surveys is that the environmental conditions change over time so that the experiment is insufficiently repeatable. To mitigate this problem, we propose the use of interferometric least-squares migration (ILSM) to estimate the migration image for the baseline and monitor surveys. Here, a known reflector is used as the reference reflector for ILSM. Results with synthetic and field data show that ILSM can eliminate artifacts caused by non-repeatability in time-lapse surveys.

  4. Seismic time-lapse imaging using Interferometric least-squares migration

    KAUST Repository

    Sinha, Mrinal; Schuster, Gerard T.

    2016-01-01

    One of the problems with 4D surveys is that the environmental conditions change over time so that the experiment is insufficiently repeatable. To mitigate this problem, we propose the use of interferometric least-squares migration (ILSM) to estimate the migration image for the baseline and monitor surveys. Here, a known reflector is used as the reference reflector for ILSM. Results with synthetic and field data show that ILSM can eliminate artifacts caused by non-repeatability in time-lapse surveys.

  5. Untangling cell tracks: Quantifying cell migration by time lapse image data analysis.

    Science.gov (United States)

    Svensson, Carl-Magnus; Medyukhina, Anna; Belyaev, Ivan; Al-Zaben, Naim; Figge, Marc Thilo

    2018-03-01

    Automated microscopy has given researchers access to great amounts of live cell imaging data from in vitro and in vivo experiments. Much focus has been put on extracting cell tracks from such data using a plethora of segmentation and tracking algorithms, but further analysis is normally required to draw biologically relevant conclusions. Such relevant conclusions may be whether the migration is directed or not, whether the population has homogeneous or heterogeneous migration patterns. This review focuses on the analysis of cell migration data that are extracted from time lapse images. We discuss a range of measures and models used to analyze cell tracks independent of the biological system or the way the tracks were obtained. For single-cell migration, we focus on measures and models giving examples of biological systems where they have been applied, for example, migration of bacteria, fibroblasts, and immune cells. For collective migration, we describe the model systems wound healing, neural crest migration, and Drosophila gastrulation and discuss methods for cell migration within these systems. We also discuss the role of the extracellular matrix and subsequent differences between track analysis in vitro and in vivo. Besides methods and measures, we are putting special focus on the need for openly available data and code, as well as a lack of common vocabulary in cell track analysis. © 2017 International Society for Advancement of Cytometry. © 2017 International Society for Advancement of Cytometry.

  6. A Virtual Machine Migration Strategy Based on Time Series Workload Prediction Using Cloud Model

    Directory of Open Access Journals (Sweden)

    Yanbing Liu

    2014-01-01

    Full Text Available Aimed at resolving the issues of the imbalance of resources and workloads at data centers and the overhead together with the high cost of virtual machine (VM migrations, this paper proposes a new VM migration strategy which is based on the cloud model time series workload prediction algorithm. By setting the upper and lower workload bounds for host machines, forecasting the tendency of their subsequent workloads by creating a workload time series using the cloud model, and stipulating a general VM migration criterion workload-aware migration (WAM, the proposed strategy selects a source host machine, a destination host machine, and a VM on the source host machine carrying out the task of the VM migration. Experimental results and analyses show, through comparison with other peer research works, that the proposed method can effectively avoid VM migrations caused by momentary peak workload values, significantly lower the number of VM migrations, and dynamically reach and maintain a resource and workload balance for virtual machines promoting an improved utilization of resources in the entire data center.

  7. Juvenile angiofibroma

    Science.gov (United States)

    Nasal tumor; Angiofibroma - juvenile; Benign nasal tumor; Juvenile nasal angiofibroma; JNA ... Juvenile angiofibroma is not very common. It is most often found in adolescent boys. The tumor contains many blood ...

  8. Time scales of DNAPL migration in sandy aquifers examined via numerical simulation

    Energy Technology Data Exchange (ETDEWEB)

    Gerhard, J.I.; Pang, T.; Kueper, B.H. [University of Edinburgh, Edinburgh (United Kingdom). Inst. of Infrastructure & Environmental

    2007-03-15

    The time required for dense nonaqueous phase liquid (DNAPL) to cease migrating following release to the subsurface is a valuable component of a site conceptual model. This study uses numerical simulation to investigate the migration of six different DNAPLs in sandy aquifers. The most influential parameters governing migration cessation time are the density and viscosity of the DNAPL and the mean hydraulic conductivity of the aquifer. Releases of between 1 and 40 drums of chlorinated solvent DNAPLs, characterized by relatively high density and low viscosity, require on the order of months to a few years to cease migrating in a heterogeneous medium sand aquifer having an average hydraulic conductivity of 7.4 x 10{sup -3} cm/s. In contrast to this, the release of 20 drums of coal tar {rho}{sub D} = 1061 kg/m{sup 3}, {mu}{sub D} = 0.161 Pa(.)s) requires more than 100 years to cease migrating in the same aquifer. Altering the mean hydraulic conductivity of the aquifer results in a proportional change in cessation times. Parameters that exhibit relatively little influence on migration time scales are the DNAPL-water interfacial tension, release volume, source capillary pressure, mean aquifer porosity, and ambient ground water hydraulic gradient. This study also demonstrates that low-density DNAPLs (e.g., coal tar) give rise to greater amounts of lateral spreading and greater amounts of pooling on capillary barriers than high-density DNAPLs such as trichloroethylene or tetrachloroethylene.

  9. Time-lapse cinematography of the capillary tube cell migration inhibition test.

    Science.gov (United States)

    Bray, M A

    1980-01-01

    The kinetics of human and guinea pig cell migration inhibition have been studied using time-lapse cinematography of cells migrating from capillary tubes. Guinea pig and human cells exhibit markedly different kinetics in the absence of inhibitors. Specific antigen causes a dose-related inhibition of migration for up to 60 h using guinea pig cells and a peak of inhibition after 18 h using the human leucocyte system. The timing of measurement of maximum activity more critical for the latter test. The kinetics of lymphokine generation have been examined and the migration inhibitory activity of the plant mitogen (PHA), a Kurloff cell product and a continuous cell line supernatant have been compared with the inhibitory profiles of lymphokine preparations and specific antigen.

  10. Multipathing Via Three Parameter Common Image Gathers (CIGs) From Reverse Time Migration

    Science.gov (United States)

    Ostadhassan, M.; Zhang, X.

    2015-12-01

    A noteworthy problem for seismic exploration is effects of multipathing (both wanted or unwanted) caused by subsurface complex structures. We show that reverse time migration (RTM) combined with a unified, systematic three parameter framework that flexibly handles multipathing can be accomplished by adding one more dimension (image time) to the angle domain common image gather (ADCIG) data. RTM is widely used to generate prestack depth migration images. When using the cross-correlation image condition in 2D prestack migration in RTM, the usual practice is to sum over all the migration time steps. Thus all possible wave types and paths automatically contribute to the resulting image, including destructive wave interferences, phase shifts, and other distortions. One reason is that multipath (prismatic wave) contributions are not properly sorted and mapped in the ADCIGs. Also, multipath arrivals usually have different instantaneous attributes (amplitude, phase and frequency), and if not separated, the amplitudes and phases in the final prestack image will not stack coherently across sources. A prismatic path satisfies an image time for it's unique path; Cavalca and Lailly (2005) show that RTM images with multipaths can provide more complete target information in complex geology, as multipaths usually have different incident angles and amplitudes compared to primary reflections. If the image time slices within a cross-correlation common-source migration are saved for each image time, this three-parameter (incident angle, depth, image time) volume can be post-processed to generate separate, or composite, images of any desired subset of the migrated data. Images can by displayed for primary contributions, any combination of primary and multipath contributions (with or without artifacts), or various projections, including the conventional ADCIG (angle vs depth) plane. Examples show that signal from the true structure can be separated from artifacts caused by multiple

  11. Bats on a Budget: Torpor-Assisted Migration Saves Time and Energy

    Science.gov (United States)

    McGuire, Liam P.; Jonasson, Kristin A.; Guglielmo, Christopher G.

    2014-01-01

    Bats and birds must balance time and energy budgets during migration. Migrating bats face similar physiological challenges to birds, but nocturnality creates special challenges for bats, such as a conflict between travelling and refueling, which many birds avoid by feeding in daylight and flying at night. As endothermic animals, bats and birds alike must expend substantial amounts of energy to maintain high body temperatures. For migratory birds refueling at stopovers, remaining euthermic during inactive periods reduces the net refuelling rate, thereby prolonging stopover duration and delaying subsequent movement. We hypothesized that bats could mitigate similar ambient-temperature dependent costs by using a torpor-assisted migration strategy. We studied silver-haired bats Lasionycteris noctivagans during autumn migration using a combination of respirometry and temperature-sensitive radiotelemetry to estimate energy costs incurred under ambient temperature conditions, and the energy that bats saved by using torpor during daytime roosting periods. All bats, regardless of sex, age, or body condition used torpor at stopover and saved up to 91% of the energy they would have expended to remain euthermic. Furthermore, bats modulated use of torpor depending on ambient temperature. By adjusting the time spent torpid, bats achieved a rate of energy expenditure independent of the ambient temperature encountered at stopover. By lowering body temperature during inactive periods, fuel stores are spared, reducing the need for refuelling. Optimal migration models consider trade-offs between time and energy. Heterothermy provides a physiological strategy that allows bats to conserve energy without paying a time penalty as they migrate. Although uncommon, some avian lineages are known to use heterothermy, and current theoretical models of migration may not be appropriate for these groups. We propose that thermoregulatory strategies should be an important consideration of future

  12. Can lagrangian models reproduce the migration time of European eel obtained from otolith analysis?

    Science.gov (United States)

    Rodríguez-Díaz, L.; Gómez-Gesteira, M.

    2017-12-01

    European eel can be found at the Bay of Biscay after a long migration across the Atlantic. The duration of migration, which takes place at larval stage, is of primary importance to understand eel ecology and, hence, its survival. This duration is still a controversial matter since it can range from 7 months to > 4 years depending on the method to estimate duration. The minimum migration duration estimated from our lagrangian model is similar to the duration obtained from the microstructure of eel otoliths, which is typically on the order of 7-9 months. The lagrangian model showed to be sensitive to different conditions like spatial and time resolution, release depth, release area and initial distribution. In general, migration showed to be faster when decreasing the depth and increasing the resolution of the model. In average, the fastest migration was obtained when only advective horizontal movement was considered. However, faster migration was even obtained in some cases when locally oriented random migration was taken into account.

  13. Grasping Legal Time : A Legal and Philosophical Analysis of the Role of Time in European Migration Law.

    NARCIS (Netherlands)

    Stronks, Martijn

    2017-01-01

    This book is about time, law and migrants. It consists of a legal and philosophical scrutiny into the question: why do migrants receive stronger rights over the course of time in European migration law? That migrants receive stronger rights over time is easily proven, much more difficult is the

  14. Assessing Task Migration Impact on Embedded Soft Real-Time Streaming Multimedia Applications

    Directory of Open Access Journals (Sweden)

    Alimonda Andrea

    2008-01-01

    Full Text Available Abstract Multiprocessor systems on chips (MPSoCs are envisioned as the future of embedded platforms such as game-engines, smart-phones and palmtop computers. One of the main challenge preventing the widespread diffusion of these systems is the efficient mapping of multitask multimedia applications on processing elements. Dynamic solutions based on task migration has been recently explored to perform run-time reallocation of task to maximize performance and optimize energy consumption. Even if task migration can provide high flexibility, its overhead must be carefully evaluated when applied to soft real-time applications. In fact, these applications impose deadlines that may be missed during the migration process. In this paper we first present a middleware infrastructure supporting dynamic task allocation for NUMA architectures. Then we perform an extensive characterization of its impact on multimedia soft real-time applications using a software FM Radio benchmark.

  15. Assessing Task Migration Impact on Embedded Soft Real-Time Streaming Multimedia Applications

    Directory of Open Access Journals (Sweden)

    Andrea Acquaviva

    2008-01-01

    Full Text Available Multiprocessor systems on chips (MPSoCs are envisioned as the future of embedded platforms such as game-engines, smart-phones and palmtop computers. One of the main challenge preventing the widespread diffusion of these systems is the efficient mapping of multitask multimedia applications on processing elements. Dynamic solutions based on task migration has been recently explored to perform run-time reallocation of task to maximize performance and optimize energy consumption. Even if task migration can provide high flexibility, its overhead must be carefully evaluated when applied to soft real-time applications. In fact, these applications impose deadlines that may be missed during the migration process. In this paper we first present a middleware infrastructure supporting dynamic task allocation for NUMA architectures. Then we perform an extensive characterization of its impact on multimedia soft real-time applications using a software FM Radio benchmark.

  16. Improving imaging quality using least-squares reverse time migration: application to data from Bohai basin

    KAUST Repository

    Zhang, Hao; Liu, Qiancheng; Wu, Jizhong

    2017-01-01

    Least-squares reverse time migration (LSRTM) is a seismic imaging technique based on linear inversion, which usually aims to improve the quality of seismic image through removing the acquisition footprint, suppressing migration artifacts, and enhancing resolution. LSRTM has been shown to produce migration images with better quality than those computed by conventional migration. In this paper, our derivation of LSRTM approximates the near-incident reflection coefficient with the normal-incident reflection coefficient, which shows that the reflectivity term defined is related to the normal-incident reflection coefficient and the background velocity. With reflected data, LSRTM is mainly sensitive to impedance perturbations. According to an approximate relationship between them, we reformulate the perturbation related system into a reflection-coefficient related one. Then, we seek the inverted image through linearized iteration. In the proposed algorithm, we only need the migration velocity for LSRTM considering that the density changes gently when compared with migration velocity. To validate our algorithms, we first apply it to a synthetic case and then a field data set. Both applications illustrate that our imaging results are of good quality.

  17. Improving imaging quality using least-squares reverse time migration: application to data from Bohai basin

    KAUST Repository

    Zhang, Hao

    2017-07-07

    Least-squares reverse time migration (LSRTM) is a seismic imaging technique based on linear inversion, which usually aims to improve the quality of seismic image through removing the acquisition footprint, suppressing migration artifacts, and enhancing resolution. LSRTM has been shown to produce migration images with better quality than those computed by conventional migration. In this paper, our derivation of LSRTM approximates the near-incident reflection coefficient with the normal-incident reflection coefficient, which shows that the reflectivity term defined is related to the normal-incident reflection coefficient and the background velocity. With reflected data, LSRTM is mainly sensitive to impedance perturbations. According to an approximate relationship between them, we reformulate the perturbation related system into a reflection-coefficient related one. Then, we seek the inverted image through linearized iteration. In the proposed algorithm, we only need the migration velocity for LSRTM considering that the density changes gently when compared with migration velocity. To validate our algorithms, we first apply it to a synthetic case and then a field data set. Both applications illustrate that our imaging results are of good quality.

  18. Frequency of abnormal hand and wrist radiographs at time of diagnosis of polyarticular juvenile rheumatoid arthritis.

    Science.gov (United States)

    Mason, Tom; Reed, Ann M; Nelson, Audrey M; Thomas, Kristen B; Patton, Alice; Hoffman, Alan D; Achenbach, Sara; O'Fallon, William M

    2002-10-01

    To determine the frequency of radiographic abnormalities in hand/wrist radiographs of children with newly diagnosed polyarticular juvenile rheumatoid arthritis (polyJRA) because radiographs of small joints are an important tool in assessing outcomes in RA and there are clinical similarities between RA and polyJRA. A medical record review was performed to identify cases of polyJRA seen at Mayo Clinic from January 1, 1994, to December 31, 2001. Hand/wrist radiographs, obtained at the time of diagnosis, were reviewed by 3 radiologists with attention to periarticular osteopenia, joint space narrowing (JSN), or erosion. At least 2 radiologists had to independently identify abnormal findings on the same radiograph. The relative carpal length (RCL), judged by Poznanski's method, was also determined. From the review of 159 medical records, 60 cases of newly diagnosed polyJRA were identified. Twenty-five of these had hand/wrist radiographs at diagnosis; 18 sets were available for this study. Of those, 2/3 were female, 6% (1/18) had subcutaneous nodules, 7% (1/14) had elevated levels of serum rheumatoid factor, and 44% (7/16) had elevated serum levels of antinuclear antibodies. Median age at diagnosis was 10.2 years, median duration of hand/wrist symptoms at diagnosis was 10 months, and median number of joints with either swelling, pain on range of motion (ROM), or limited ROM was 14.5. Sixty-one percent of radiographs taken at the time of diagnosis of polyJRA were abnormal. While 44% had periarticular osteopenia, 28% had either erosions or JSN. Six (33%) had RCL > 2 SD below the mean for age. Five (83%) of those with RCL, > 2 SD below the mean for age, had periarticular osteopenia, JSN, or erosion. We conclude the frequency of abnormal hand/wrist radiographs is very high very early in the course of polyJRA. More studies are needed to determine to what extent these radiographic abnormalities correlate with clinical outcomes.

  19. Migration and common mental disorder: an improvement in mental health over time?

    Science.gov (United States)

    Butler, Margaret; Warfa, Nasir; Khatib, Yasmin; Bhui, Kamaldeep

    2015-02-01

    Global migration is reaching record high levels and UK migrant groups comprise an increasing proportion of the total population. The migratory process causes stress that can affect mental health. There is limited consistent empirical evidence of a longitudinal nature to explain the association between migration and mental health. This review aims to examine the evidence of a relationship between migration and common mental disorder (CMD) amongst migrants over time. A comprehensive search of medical and psychiatric databases for global quantitative empirical studies investigating incidence of CMD amongst adult migrants from 1975 to July 2012 was conducted. Declines in rates of CMD amongst migrants over time were reported by two thirds of the 18 studies reviewed, less than one third of which were statistically significant. On the contrary, three studies showed an increased rate of CMD, one statistically significant. Individual psychological resources, social support, the acculturation process, cultural variations and time since relocation are identified as statistically significant protective factors against the development of CMD amongst migrants. New enlightening points include the significant impact of varying patterns of psychological distress, of which negative is the most adverse for CMD. Migration is an extremely complex process. Further clarification is needed to gain deeper understanding of the relationship between migration and CMD to address contradictions in the literature and health inequalities amongst migrants.

  20. Patterns of change in timing of spring migration in North European songbird populations

    DEFF Research Database (Denmark)

    Tøttrup, Anders Peter; Thorup, Kasper; Rahbek, Carsten

    2006-01-01

    From 1976 to 1997 passerines were mist-netted and ringed on the island of Christiansø, in the Baltic Sea. Here we present analyses of phenological changes (i.e. time of arrival) for 25 species based on the entire populations of mist-netted songbirds during spring migration. We used two approaches...... to be important for our understanding of population-dynamic changes in relation to climate change. These differences may also have long-term evolutionary consequences. Migration distance seems to affect the degree of change in arrival time, but we found no difference between species wintering in different regions...... of Africa....

  1. Local temperature fine-tunes the timing of spring migration in birds

    DEFF Research Database (Denmark)

    Tøttrup, Anders P.; Rainio, Kalle; Coppack, Timothy

    2010-01-01

    and predict consequences of climatic change for migratory birds. In order to better understand migration phenology and adaptation in environmental changes, we here assess the scale at which weather affects timing of spring migration in passerine birds. We use three commonly used proxies of spring......-time climatic conditions: (1) vegetation "greenness" (NDVI) in Europe, (2) local spring temperatures in northern Europe, and (3) the North Atlantic Oscillation Index (NAO) as predictors of the phenology of avian migration as well as the strength of their effect on different subsets of populations...... breeding area. Local temperature was the best single predictor of phenology with the highest explanatory power achieved in combination with NAO. Furthermore, early individuals are more affected by climatic variation compared to individuals on later passage, indicating that climatic change affects subsets...

  2. Time-domain least-squares migration using the Gaussian beam summation method

    Science.gov (United States)

    Yang, Jidong; Zhu, Hejun; McMechan, George; Yue, Yubo

    2018-04-01

    With a finite recording aperture, a limited source spectrum and unbalanced illumination, traditional imaging methods are insufficient to generate satisfactory depth profiles with high resolution and high amplitude fidelity. This is because traditional migration uses the adjoint operator of the forward modeling rather than the inverse operator. We propose a least-squares migration approach based on the time-domain Gaussian beam summation, which helps to balance subsurface illumination and improve image resolution. Based on the Born approximation for the isotropic acoustic wave equation, we derive a linear time-domain Gaussian beam modeling operator, which significantly reduces computational costs in comparison with the spectral method. Then, we formulate the corresponding adjoint Gaussian beam migration, as the gradient of an L2-norm waveform misfit function. An L1-norm regularization is introduced to the inversion to enhance the robustness of least-squares migration, and an approximated diagonal Hessian is used as a preconditioner to speed convergence. Synthetic and field data examples demonstrate that the proposed approach improves imaging resolution and amplitude fidelity in comparison with traditional Gaussian beam migration.

  3. If and when: Intrinsic differences and environmental stressors influence migration in brown trout (Salmo trutta)

    DEFF Research Database (Denmark)

    Peiman, K. S.; Birnie-Gauvin, Kim; Midwood, J. D.

    2017-01-01

    Partial migration is a common phenomenon, yet the causes of individual differences in migratory propensity are not well understood. We examined factors that potentially influence timing of migration and migratory propensity in a wild population of juvenile brown trout (Salmo trutta) by combining...

  4. Determine the Influence of Time Held in “Knockdown” Anesthesia on Survival and Stress of Surgically Implanted Juvenile Salmonids

    Energy Technology Data Exchange (ETDEWEB)

    Woodley, Christa M.; Wagner, Katie A.; Knox, Kasey M.

    2012-01-31

    The Juvenile Salmon Acoustic Telemetry System (JSATS) was developed for the U.S. Army Corp of Engineers Portland District (USACE) to address questions related to survival and performance measures of juvenile salmonids as they pass through the Federal Columbia River Power System (FCRPS). Researchers using JSATS acoustic transmitters (ATs) were tasked with standardizing the surgical implantation procedure to ensure that the stressors of handling and surgery on salmonids were consistent and less likely to cause effects of tagging in survival studies. Researchers questioned whether the exposure time in 'knockdown' anesthesia (or induction) to prepare fish for surgery could influence the survival of study fish (CBSPSC 2011). Currently, fish are held in knockdown anesthesia after they reach Stage 4 anesthesia until the completion of the surgical implantation of a transmitter, varies from 5 to 15 minutes for studies conducted in the Columbia Basin. The Columbia Basin Surgical Protocol Steering Committee (CBSPSC ) expressed concern that its currently recommended 10-minute maximum time limit during which fish are held in anesthetic - tricaine methanesulfonate (MS-222, 80 mg L-1 water) - could increase behavioral and physiological costs, and/or decrease survival of outmigrating juvenile salmonids. In addition, the variability in the time fish are held at Stage 4 could affect the data intended for direct comparison of fish within or among survival studies. Under the current recommended protocol, if fish exceed the 10-minute time limit, they are to be released without surgical implantation, thereby increasing the number of fish handled and endangered species 'take' at the bypass systems for FCRPS survival studies.

  5. Temperature affects the timing of spawning and migration of North Sea mackerel

    DEFF Research Database (Denmark)

    Jansen, Teunis; Gislason, Henrik

    2011-01-01

    Climate change accentuates the need for knowing how temperature impacts the life history and productivity of economically and ecologically important species of fish. We examine the influence of temperature on the timing of the spawning and migrations of North Sea Mackerel using data from larvae C...

  6. Climate change and timing of avian breeding and migration: evolutionary versus plastic changes

    NARCIS (Netherlands)

    Charmantier, A.; Gienapp, P.

    2014-01-01

    There are multiple observations around the globe showing that in many avian species, both the timing of migration and breeding have advanced, due to warmer springs. Here, we review the literature to disentangle the actions of evolutionary changes in response to selection induced by climate change

  7. Treatment with escitalopram but not desipramine decreases escape latency times in a learned helplessness model using juvenile rats.

    Science.gov (United States)

    Reed, Abbey L; Anderson, Jeffrey C; Bylund, David B; Petty, Frederick; El Refaey, Hesham; Happe, H Kevin

    2009-08-01

    The pharmacological treatment of depression in children and adolescents is different from that of adults due to the lack of efficacy of certain antidepressants in the pediatric age group. Our current understanding of why these differences occur is very limited. To develop more effective treatments, a juvenile animal model of depression was tested to validate it as a possible model to specifically study pediatric depression. Procedures for use with juvenile rats at postnatal day (PND) 21 and 28 were adapted from the adult learned helplessness model in which, 24 h after exposure to inescapable stress, animals are unable to remove themselves from an easily escapable stressor. Rats were treated for 7 days with either the selective serotonin reuptake inhibitor escitalopram at 10 mg/kg or the tricyclic antidepressant desipramine at 3, 10, or 15 mg/kg to determine if treatment could decrease escape latency times. Escitalopram treatment was effective at decreasing escape latency times in all ages tested. Desipramine treatment did not decrease escape latency times for PND 21 rats, but did decrease times for PND 28 and adult animals. The learned helplessness model with PND 21 rats predicts the efficacy of escitalopram and the lack of efficacy of desipramine seen in the treatment of pediatric depression. These findings suggest that the use of PND 21 rats in a modified learned helplessness procedure may be a valuable model of human pediatric depression that can predict pediatric antidepressant efficacy and be used to study antidepressant mechanisms involved in pediatric depression.

  8. Juvenile magma recognition and eruptive dynamics inferred from the analysis of ash time series: The 2015 reawakening of Cotopaxi volcano

    Science.gov (United States)

    Gaunt, H. Elizabeth; Bernard, Benjamin; Hidalgo, Silvana; Proano, Antonio; Wright, Heather M.; Mothes, Patricia; Criollo, Evelyn; Kueppers, Ulrich

    2016-01-01

    Forecasting future activity and performing hazard assessments during the reactivation of volcanoes remain great challenges for the volcanological community. On August 14, 2015 Cotopaxi volcano erupted for the first time in 73 years after approximately four months of precursory activity, which included an increase in seismicity, gas emissions, and minor ground deformation. Here we discuss the use of near real-time petrological monitoring of ash samples as a complementary aid to geophysical monitoring, in order to infer eruption dynamics and evaluate possible future eruptive activity at Cotopaxi. Twenty ash samples were collected between August 14 and November 23, 2015 from a monitoring site on the west flank of the volcano. These samples contain a range of grain types that we classified as: hydrothermal/altered, lithic, juvenile, and free crystals. The relative proportions of theses grains evolved as the eruption progressed, with increasing amounts of juvenile material and a decrease in hydrothermally altered material. In samples from the initial explosion, juvenile grains are glassy, microlite-poor and contain hydrothermal minerals (opal and alunite). The rising magma came in contact with the hydrothermal system under confinement, causing hydro-magmatic explosions that cleared the upper part of the plumbing system. Subsequently, the magmatic column produced a thermal aureole in the conduit and dried out the hydrothermal system, allowing for dry eruptions. Magma ascent rates were low enough to allow for efficient outgassing and microlite growth. Constant supply of magma from below caused quasi-continuous disruption of the uppermost magma volume through a combination of shear-deformation and gas expansion. The combination of increasing crystallinity of juvenile grains, and high measured SO2 flux indicate decreasing integrated magma ascent rates and clearing of the hydrothermal system along transport pathways in a system open to gas loss. The near real-time

  9. Final Project Report: Imaging Fault Zones Using a Novel Elastic Reverse-Time Migration Imaging Technique

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Lianjie [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chen, Ting [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tan, Sirui [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lin, Youzuo [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gao, Kai [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-05-10

    Imaging fault zones and fractures is crucial for geothermal operators, providing important information for reservoir evaluation and management strategies. However, there are no existing techniques available for directly and clearly imaging fault zones, particularly for steeply dipping faults and fracture zones. In this project, we developed novel acoustic- and elastic-waveform inversion methods for high-resolution velocity model building. In addition, we developed acoustic and elastic reverse-time migration methods for high-resolution subsurface imaging of complex subsurface structures and steeply-dipping fault/fracture zones. We first evaluated and verified the improved capabilities of our newly developed seismic inversion and migration imaging methods using synthetic seismic data. Our numerical tests verified that our new methods directly image subsurface fracture/fault zones using surface seismic reflection data. We then applied our novel seismic inversion and migration imaging methods to a field 3D surface seismic dataset acquired at the Soda Lake geothermal field using Vibroseis sources. Our migration images of the Soda Lake geothermal field obtained using our seismic inversion and migration imaging algorithms revealed several possible fault/fracture zones. AltaRock Energy, Inc. is working with Cyrq Energy, Inc. to refine the geologic interpretation at the Soda Lake geothermal field. Trenton Cladouhos, Senior Vice President R&D of AltaRock, was very interested in our imaging results of 3D surface seismic data from the Soda Lake geothermal field. He planed to perform detailed interpretation of our images in collaboration with James Faulds and Holly McLachlan of University of Nevada at Reno. Using our high-resolution seismic inversion and migration imaging results can help determine the optimal locations to drill wells for geothermal energy production and reduce the risk of geothermal exploration.

  10. 3D Multi‐source Least‐squares Reverse Time Migration

    KAUST Repository

    Dai, Wei

    2010-10-17

    We present the theory and numerical results for least‐squares reverse time migration (LSRTM) of phase‐encoded supergathers, where each supergather is the superposition of phased‐encoded shots. Three type of encoding functions are used in this study: random time shift, random source polarity and random source location selected from a pre‐designed table. Numerical tests for the 3D SEG/EAGE Overthrust model show that multi‐source LSRTM can suppress migration artifacts in the migration image and remove most of the crosstalk noise from multi‐source data. Empirical results suggest that multi‐source LSRTM can provide a noticeable increase in computational efficiency compared to standard RTM, when the CSGs in a supergather are modeled and migrated together with a finite‐difference simulator. If the phase‐encoding functions are dynamically changed after each iteration of LSRTM, the best images are obtained. The potential drawback is that the final results are very sensitive to the accuracy of the starting model.

  11. Attenuation compensation for least-squares reverse time migration using the viscoacoustic-wave equation

    KAUST Repository

    Dutta, Gaurav

    2014-10-01

    Strong subsurface attenuation leads to distortion of amplitudes and phases of seismic waves propagating inside the earth. Conventional acoustic reverse time migration (RTM) and least-squares reverse time migration (LSRTM) do not account for this distortion, which can lead to defocusing of migration images in highly attenuative geologic environments. To correct for this distortion, we used a linearized inversion method, denoted as Qp-LSRTM. During the leastsquares iterations, we used a linearized viscoacoustic modeling operator for forward modeling. The adjoint equations were derived using the adjoint-state method for back propagating the residual wavefields. The merit of this approach compared with conventional RTM and LSRTM was that Qp-LSRTM compensated for the amplitude loss due to attenuation and could produce images with better balanced amplitudes and more resolution below highly attenuative layers. Numerical tests on synthetic and field data illustrated the advantages of Qp-LSRTM over RTM and LSRTM when the recorded data had strong attenuation effects. Similar to standard LSRTM, the sensitivity tests for background velocity and Qp errors revealed that the liability of this method is the requirement for smooth and accurate migration velocity and attenuation models.

  12. Attenuation compensation for least-squares reverse time migration using the viscoacoustic-wave equation

    KAUST Repository

    Dutta, Gaurav; Schuster, Gerard T.

    2014-01-01

    Strong subsurface attenuation leads to distortion of amplitudes and phases of seismic waves propagating inside the earth. Conventional acoustic reverse time migration (RTM) and least-squares reverse time migration (LSRTM) do not account for this distortion, which can lead to defocusing of migration images in highly attenuative geologic environments. To correct for this distortion, we used a linearized inversion method, denoted as Qp-LSRTM. During the leastsquares iterations, we used a linearized viscoacoustic modeling operator for forward modeling. The adjoint equations were derived using the adjoint-state method for back propagating the residual wavefields. The merit of this approach compared with conventional RTM and LSRTM was that Qp-LSRTM compensated for the amplitude loss due to attenuation and could produce images with better balanced amplitudes and more resolution below highly attenuative layers. Numerical tests on synthetic and field data illustrated the advantages of Qp-LSRTM over RTM and LSRTM when the recorded data had strong attenuation effects. Similar to standard LSRTM, the sensitivity tests for background velocity and Qp errors revealed that the liability of this method is the requirement for smooth and accurate migration velocity and attenuation models.

  13. Decadal shifts in autumn migration timing by Pacific Arctic beluga whales are related to delayed annual sea ice formation.

    Science.gov (United States)

    Hauser, Donna D W; Laidre, Kristin L; Stafford, Kathleen M; Stern, Harry L; Suydam, Robert S; Richard, Pierre R

    2017-06-01

    Migrations are often influenced by seasonal environmental gradients that are increasingly being altered by climate change. The consequences of rapid changes in Arctic sea ice have the potential to affect migrations of a number of marine species whose timing is temporally matched to seasonal sea ice cover. This topic has not been investigated for Pacific Arctic beluga whales (Delphinapterus leucas) that follow matrilineally maintained autumn migrations in the waters around Alaska and Russia. For the sympatric Eastern Chukchi Sea ('Chukchi') and Eastern Beaufort Sea ('Beaufort') beluga populations, we examined changes in autumn migration timing as related to delayed regional sea ice freeze-up since the 1990s, using two independent data sources (satellite telemetry data and passive acoustics) for both populations. We compared dates of migration between 'early' (1993-2002) and 'late' (2004-2012) tagging periods. During the late tagging period, Chukchi belugas had significantly delayed migrations (by 2 to >4 weeks, depending on location) from the Beaufort and Chukchi seas. Spatial analyses also revealed that departure from Beaufort Sea foraging regions by Chukchi whales was postponed in the late period. Chukchi beluga autumn migration timing occurred significantly later as regional sea ice freeze-up timing became later in the Beaufort, Chukchi, and Bering seas. In contrast, Beaufort belugas did not shift migration timing between periods, nor was migration timing related to freeze-up timing, other than for southward migration at the Bering Strait. Passive acoustic data from 2008 to 2014 provided independent and supplementary support for delayed migration from the Beaufort Sea (4 day yr -1 ) by Chukchi belugas. Here, we report the first phenological study examining beluga whale migrations within the context of their rapidly transforming Pacific Arctic ecosystem, suggesting flexible responses that may enable their persistence yet also complicate predictions of how

  14. Time-dependent tegumental surface changes in juvenile Fasciola gigantica in response to triclabendazole treatment in goat.

    Science.gov (United States)

    Shareef, P A Ahammed; Brennan, Gerard P; McVeigh, Paul; Khan, M A Hannan; Morphew, Russell M; Mousley, Angela; Marks, Nikki J; Saifullah, M K; Brophy, Peter M; Maule, Aaron G; Abidi, S M A

    2014-08-01

    Triclabendazole (TCBZ), the anthelmintic drug active against both mature and immature liver flukes, was used to investigate the effect of in vivo treatment on the tegumental surface of juvenile Fasciola gigantica. Five goats were infected with 150 F. gigantica metacercariae each by oral gavage. Four of them were treated with single dose of TCBZ at 10mg/kg at four weeks post-infection. They were euthanized at 0 (untreated), 24, 48, 72 and 96h post treatment. Juvenile flukes were manually retrieved from the goat livers and processed for scanning electron microscopy. In control flukes, the anterior region was adorned with sharply pointed spines projecting away from the surface, while in the posterior region, spines become shorter and narrower, loosing serration and with the appearance of distinct furrows and papillae. The dorsal surface retained the same pattern of surface architecture similar to that of ventral surface. Flukes obtained from 24h post-treatment did not show any apparent change and were still very active. However, there were limited movements and some blebbing, swelling, deposition of tegumental secretions and some flattening displayed by the flukes of 48h post-treatment. All the worms were found dead 72h post-treatment and showed advanced level of tegumental disruptions, consisting of severe distortion of spines, sloughing off the tegument to expose the basal lamina, formation of pores and isolated patches of lesions. By 96h post-treatment, the disruption was extremely severe and the tegument was completely sheared off causing deeper lesions that exposed the underlying musculature. The disruption was more severe at posterior than anterior region and on ventral than dorsal surface. The present study further establishes the time-course of TCBZ action in vivo with 100% efficacy against the juvenile tropical liver fluke. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Imaging Fracking Zones by Microseismic Reverse Time Migration for Downhole Microseismic Monitoring

    Science.gov (United States)

    Lin, Y.; Zhang, H.

    2015-12-01

    Hydraulic fracturing is an engineering tool to create fractures in order to better recover oil and gas from low permeability reservoirs. Because microseismic events are generally associated with fracturing development, microseismic monitoring has been used to evaluate the fracking process. Microseismic monitoring generally relies on locating microseismic events to understand the spatial distribution of fractures. For the multi-stage fracturing treatment, fractures created in former stages are strong scatterers in the medium and can induce strong scattering waves on the waveforms for microseismic events induced during later stages. In this study, we propose to take advantage of microseismic scattering waves to image fracking zones by using seismic reverse time migration method. For downhole microseismic monitoring that involves installing a string of seismic sensors in a borehole near the injection well, the observation geometry is actually similar to the VSP (vertical seismic profile) system. For this reason, we adapt the VSP migration method for the common shot gather to the common event gather. Microseismic reverse-time migration method involves solving wave equation both forward and backward in time for each microseismic event. At current stage, the microseismic RTM is based on 2D acoustic wave equation (Zhang and Sun, 2008), solved by the finite-difference method with PML absorbing boundary condition applied to suppress the reflections of artificial boundaries. Additionally, we use local wavefield decomposition instead of cross-correlation imaging condition to suppress the imaging noise. For testing the method, we create a synthetic dataset for a downhole microseismic monitoring system with multiple fracking stages. It shows that microseismic migration using individual event is able to clearly reveal the fracture zone. The shorter distance between fractures and the microseismic event the clearer the migration image is. By summing migration images for many

  16. Q-Least Squares Reverse Time Migration with Viscoacoustic Deblurring Filters

    KAUST Repository

    Chen, Yuqing; Dutta, Gaurav; Dai, Wei; Schuster, Gerard T.

    2017-01-01

    Viscoacoustic least-squares reverse time migration (Q-LSRTM) linearly inverts for the subsurface reflectivity model from lossy data. Compared to the conventional migration methods, it can compensate for the amplitude loss in the migrated images because of the strong subsurface attenuation and can produce reflectors that are accurately positioned in depth. However, the adjoint Q propagators used for backward propagating the residual data are also attenuative. Thus, the inverted images from Q-LSRTM are often observed to have lower resolution when compared to the benchmark acoustic LSRTM images from acoustic data. To increase the resolution and accelerate the convergence of Q-LSRTM, we propose using viscoacoustic deblurring filters as a preconditioner for Q-LSRTM. These filters can be estimated by matching a simulated migration image to its reference reflectivity model. Numerical tests on synthetic and field data demonstrate that Q-LSRTM combined with viscoacoustic deblurring filters can produce images with higher resolution and more balanced amplitudes than images from acoustic RTM, acoustic LSRTM and Q-LSRTM when there is strong attenuation in the background medium. The proposed preconditioning method is also shown to improve the convergence rate of Q-LSRTM by more than 30 percent in some cases and significantly compensate for the lossy artifacts in RTM images.

  17. Q-Least Squares Reverse Time Migration with Viscoacoustic Deblurring Filters

    KAUST Repository

    Chen, Yuqing

    2017-08-02

    Viscoacoustic least-squares reverse time migration (Q-LSRTM) linearly inverts for the subsurface reflectivity model from lossy data. Compared to the conventional migration methods, it can compensate for the amplitude loss in the migrated images because of the strong subsurface attenuation and can produce reflectors that are accurately positioned in depth. However, the adjoint Q propagators used for backward propagating the residual data are also attenuative. Thus, the inverted images from Q-LSRTM are often observed to have lower resolution when compared to the benchmark acoustic LSRTM images from acoustic data. To increase the resolution and accelerate the convergence of Q-LSRTM, we propose using viscoacoustic deblurring filters as a preconditioner for Q-LSRTM. These filters can be estimated by matching a simulated migration image to its reference reflectivity model. Numerical tests on synthetic and field data demonstrate that Q-LSRTM combined with viscoacoustic deblurring filters can produce images with higher resolution and more balanced amplitudes than images from acoustic RTM, acoustic LSRTM and Q-LSRTM when there is strong attenuation in the background medium. The proposed preconditioning method is also shown to improve the convergence rate of Q-LSRTM by more than 30 percent in some cases and significantly compensate for the lossy artifacts in RTM images.

  18. Least-squares reverse time migration of marine data with frequency-selection encoding

    KAUST Repository

    Dai, Wei

    2013-06-24

    The phase-encoding technique can sometimes increase the efficiency of the least-squares reverse time migration (LSRTM) by more than one order of magnitude. However, traditional random encoding functions require all the encoded shots to share the same receiver locations, thus limiting the usage to seismic surveys with a fixed spread geometry. We implement a frequency-selection encoding strategy that accommodates data with a marine streamer geometry. The encoding functions are delta functions in the frequency domain, so that all the encoded shots have unique nonoverlapping frequency content, and the receivers can distinguish the wavefield from each shot with a unique frequency band. Because the encoding functions are orthogonal to each other, there will be no crosstalk between different shots during modeling and migration. With the frequency-selection encoding method, the computational efficiency of LSRTM is increased so that its cost is comparable to conventional RTM for the Marmousi2 model and a marine data set recorded in the Gulf of Mexico. With more iterations, the LSRTM image quality is further improved by suppressing migration artifacts, balancing reflector amplitudes, and enhancing the spatial resolution. We conclude that LSRTM with frequency-selection is an efficient migration method that can sometimes produce more focused images than conventional RTM. © 2013 Society of Exploration Geophysicists.

  19. Analysis of genomic data as an approach to understanding migration in song birds

    OpenAIRE

    Boss, John

    2015-01-01

    Many species of birds migrate every year thousands of kilometers, relying on sight, memory, magnetic sensors and instincts to find their way across continents. Many juvenile birds travel complicated migration routes without the guidance of more experienced adults. To successfully accomplish this they need instincts that utilizes multiple navigational senses together with a time dependent schedule. Little is known of the genetics behind migration behavior and which cellular processes are invol...

  20. Time-Dependent Changes in T1 during Fracture Healing in Juvenile Rats: A Quantitative MR Approach.

    Directory of Open Access Journals (Sweden)

    Katharina Baron

    Full Text Available Quantitative magnetic resonance imaging (qMRI offers several advantages in imaging and determination of soft tissue alterations when compared to qualitative imaging techniques. Although applications in brain and muscle tissues are well studied, its suitability to quantify relaxation times of intact and injured bone tissue, especially in children, is widely unknown. The objective observation of a fracture including its age determination can become of legal interest in cases of child abuse or maltreatment. Therefore, the aim of this study is the determination of time dependent changes in intact and corresponding injured bones in immature rats via qMRI, to provide the basis for an objective and radiation-free approach for fracture dating. Thirty-five MR scans of 7 Sprague-Dawley rats (male, 4 weeks old, 100 ± 5 g were acquired on a 3T MRI scanner (TimTrio, Siemens AG, Erlangen, Germany after the surgical infliction of an epiphyseal fracture in the tibia. The images were taken at days 1, 3, 7, 14, 28, 42 and 82 post-surgery. A proton density-weighted and a T1-weighted 3D FLASH sequence were acquired to calculate the longitudinal relaxation time T1 of the fractured region and the surrounding tissues. The calculation of T1 in intact and injured bone resulted in a quantitative observation of bone development in intact juvenile tibiae as well as the bone healing process in the injured tibiae. In both areas, T1 decreased over time. To evaluate the differences in T1 behaviour between the intact and injured bone, the relative T1 values (bone-fracture were calculated, showing clear detectable alterations of T1 after fracture occurrence. These results indicate that qMRI has a high potential not only for clinically relevant applications to detect growth defects or developmental alterations in juvenile bones, but also for forensically relevant applications such as the dating of fractures in cases of child abuse or maltreatment.

  1. Conjugate gradient and cross-correlation based least-square reverse time migration and its application

    Science.gov (United States)

    Sun, Xiao-Dong; Ge, Zhong-Hui; Li, Zhen-Chun

    2017-09-01

    Although conventional reverse time migration can be perfectly applied to structural imaging it lacks the capability of enabling detailed delineation of a lithological reservoir due to irregular illumination. To obtain reliable reflectivity of the subsurface it is necessary to solve the imaging problem using inversion. The least-square reverse time migration (LSRTM) (also known as linearized reflectivity inversion) aims to obtain relatively high-resolution amplitude preserving imaging by including the inverse of the Hessian matrix. In practice, the conjugate gradient algorithm is proven to be an efficient iterative method for enabling use of LSRTM. The velocity gradient can be derived from a cross-correlation between observed data and simulated data, making LSRTM independent of wavelet signature and thus more robust in practice. Tests on synthetic and marine data show that LSRTM has good potential for use in reservoir description and four-dimensional (4D) seismic images compared to traditional RTM and Fourier finite difference (FFD) migration. This paper investigates the first order approximation of LSRTM, which is also known as the linear Born approximation. However, for more complex geological structures a higher order approximation should be considered to improve imaging quality.

  2. Satellite- versus temperature-derived green wave indices for predicting the timing of spring migration of avian herbivores

    NARCIS (Netherlands)

    Shariati Najafabadi, M.; Najafabadi, M.S.; Darvishzadeh, R.; Skidmore, A.K.; Kölzsch, Andrea; Vrieling, A.; Nolet, Bart A.; Exo, Klaus-Michael; Meratnia, Nirvana; Havinga, Paul J.M.; Stahl, Julia; Toxopeus, A.G.

    2015-01-01

    According to the green wave hypothesis, herbivores follow the flush of spring growth of forage plants during their spring migration to northern breeding grounds. In this study we compared two green wave indices for predicting the timing of the spring migration of avian herbivores: the

  3. Marriage Migration Versus Family Reunification : How Does the Marriage and Migration History Affect the Timing of First and Second Childbirth Among Turkish Immigrants in Germany?

    NARCIS (Netherlands)

    Wolf, Katharina

    2016-01-01

    Our study focuses on the fertility of first-generation female and male Turkish migrants in Germany. To evaluate whether timing effects such as fertility disruption or an interrelation of marriage, migration and childbirth occur, we examine first and second births in the years before and after

  4. Least-squares reverse time migration of marine data with frequency-selection encoding

    KAUST Repository

    Dai, Wei

    2013-08-20

    The phase-encoding technique can sometimes increase the efficiency of the least-squares reverse time migration (LSRTM) by more than one order of magnitude. However, traditional random encoding functions require all the encoded shots to share the same receiver locations, thus limiting the usage to seismic surveys with a fixed spread geometry. We implement a frequency-selection encoding strategy that accommodates data with a marine streamer geometry. The encoding functions are delta functions in the frequency domain, so that all the en- coded shots have unique non-overlapping frequency content, and the receivers can distinguish the wavefield from each shot with a unique frequency band. Since the encoding functions are orthogonal to each other, there will be no crosstalk between different shots during modeling and migration. With the frequency-selection encoding method, the computational efficiency of LSRTM is increased so that its cost is compara- ble to conventional RTM for both the Marmousi2 model and a marine data set recorded in the Gulf of Mexico. With more iterations, the LSRTM image quality is further improved. We conclude that LSRTM with frequency-selection is an efficient migration method that can sometimes produce more focused images than conventional RTM.

  5. Least-squares reverse time migration with local Radon-based preconditioning

    KAUST Repository

    Dutta, Gaurav

    2017-03-08

    Least-squares migration (LSM) can produce images with better balanced amplitudes and fewer artifacts than standard migration. The conventional objective function used for LSM minimizes the L2-norm of the data residual between the predicted and the observed data. However, for field-data applications in which the recorded data are noisy and undersampled, the conventional formulation of LSM fails to provide the desired uplift in the quality of the inverted image. We have developed a leastsquares reverse time migration (LSRTM) method using local Radon-based preconditioning to overcome the low signal-tonoise ratio (S/N) problem of noisy or severely undersampled data. A high-resolution local Radon transform of the reflectivity is used, and sparseness constraints are imposed on the inverted reflectivity in the local Radon domain. The sparseness constraint is that the inverted reflectivity is sparse in the Radon domain and each location of the subsurface is represented by a limited number of geologic dips. The forward and the inverse mapping of the reflectivity to the local Radon domain and vice versa is done through 3D Fourier-based discrete Radon transform operators. The weights for the preconditioning are chosen to be varying locally based on the relative amplitudes of the local dips or assigned using quantile measures. Numerical tests on synthetic and field data validate the effectiveness of our approach in producing images with good S/N and fewer aliasing artifacts when compared with standard RTM or standard LSRTM.

  6. Three-Dimensional Passive-Source Reverse-Time Migration of Converted Waves: The Method

    Science.gov (United States)

    Li, Jiahang; Shen, Yang; Zhang, Wei

    2018-02-01

    At seismic discontinuities in the crust and mantle, part of the compressional wave energy converts to shear wave, and vice versa. These converted waves have been widely used in receiver function (RF) studies to image discontinuity structures in the Earth. While generally successful, the conventional RF method has its limitations and is suited mostly to flat or gently dipping structures. Among the efforts to overcome the limitations of the conventional RF method is the development of the wave-theory-based, passive-source reverse-time migration (PS-RTM) for imaging complex seismic discontinuities and scatters. To date, PS-RTM has been implemented only in 2D in the Cartesian coordinate for local problems and thus has limited applicability. In this paper, we introduce a 3D PS-RTM approach in the spherical coordinate, which is better suited for regional and global problems. New computational procedures are developed to reduce artifacts and enhance migrated images, including back-propagating the main arrival and the coda containing the converted waves separately, using a modified Helmholtz decomposition operator to separate the P and S modes in the back-propagated wavefields, and applying an imaging condition that maintains a consistent polarity for a given velocity contrast. Our new approach allows us to use migration velocity models with realistic velocity discontinuities, improving accuracy of the migrated images. We present several synthetic experiments to demonstrate the method, using regional and teleseismic sources. The results show that both regional and teleseismic sources can illuminate complex structures and this method is well suited for imaging dipping interfaces and sharp lateral changes in discontinuity structures.

  7. Palaearctic-African Bird Migration

    DEFF Research Database (Denmark)

    Iwajomo, Soladoye Babatola

    Bird migration has attracted a lot of interests over past centuries and the methods used for studying this phenomenon has greatly improved in terms of availability, dimension, scale and precision. In spite of the advancements, relatively more is known about the spring migration of trans-Saharan m......Bird migration has attracted a lot of interests over past centuries and the methods used for studying this phenomenon has greatly improved in terms of availability, dimension, scale and precision. In spite of the advancements, relatively more is known about the spring migration of trans...... of birds from Europe to Africa and opens up the possibility of studying intra-African migration. I have used long-term, standardized autumn ringing data from southeast Sweden to investigate patterns in biometrics, phenology and population trends as inferred from annual trapping totals. In addition, I...... in the population of the species. The papers show that adult and juvenile birds can use different migration strategies depending on time of season and prevailing conditions. Also, the fuel loads of some individuals were theoretically sufficient for a direct flight to important goal area, but whether they do so...

  8. Wind conditions and geography shape the first outbound migration of juvenile honey buzzards and their distribution across sub-Saharan Africa

    Science.gov (United States)

    Kekkonen, J.; Byholm, P.

    2017-01-01

    Contemporary tracking studies reveal that low migratory connectivity between breeding and non-breeding ranges is common in migrant landbirds. It is unclear, however, how internal factors and early-life experiences of individual migrants shape the development of their migration routes and concomitant population-level non-breeding distributions. Stochastic wind conditions and geography may determine whether and where migrants end up by the end of their journey. We tested this hypothesis by satellite-tagging 31 fledgling honey buzzards Pernis apivorus from southern Finland and used a global atmospheric reanalysis model to estimate the wind conditions they encountered on their first outbound migration. Migration routes diverged rapidly upon departure and the birds eventually spread out across 3340 km of longitude. Using linear regression models, we show that the birds' longitudinal speeds were strongly affected by zonal wind speed, and negatively affected by latitudinal wind, with significant but minor differences between individuals. Eventually, 49% of variability in the birds' total longitudinal displacements was accounted for by wind conditions on migration. Some birds circumvented the Baltic Sea via Scandinavia or engaged in unusual downwind movements over the Mediterranean, which also affected the longitude at which these individuals arrived in sub-Saharan Africa. To understand why adult migrants use the migration routes and non-breeding sites they use, we must take into account the way in which wind conditions moulded their very first journeys. Our results present some of the first evidence into the mechanisms through which low migratory connectivity emerges. PMID:28539514

  9. Kinetic behaviours of aggregate growth driven by time-dependent migration, birth and death

    International Nuclear Information System (INIS)

    Zhu Shengqing; Yang Shunyou; Ke Jianhong; Lin Zhenquan

    2008-01-01

    We propose a dynamic growth model to mimic some social phenomena, such as the evolution of cities' population, in which monomer migrations occur between any two aggregates and monomer birth/death can simultaneously occur in each aggregate. Considering the fact that the rate kernels of migration, birth and death processes may change with time, we assume that the migration rate kernel is ijf(t), and the self-birth and death rate kernels are ig 1 (t) and ig 2 (t), respectively. Based on the mean-field rate equation, we obtain the exact solution of this model and then discuss semi-quantitatively the scaling behaviour of the aggregate size distribution at large times. The results show that in the long-time limit, (i) if ∫ t 0 g 1 (t') dt'/∫ t 0 g 2 (t') dt' ≥ 1 or exp{∫ t 0 [g 2 (t') - g 1 (t')] dt'}/∫ t 0 f(t') dt' → 0, the aggregate size distribution a k (t) can obey a generalized scaling form; (ii) if ∫ t 0 g 1 (t') dt'/∫ t 0 g 2 (t') dt' → 0 and exp ∫ t 0 [g 2 (t') - g 1 (t') dt'/∫ t 0 f(t') dt' → ∞, a k (t) can take a scale-free form and decay exponentially in size k; (iii) a k (t) will satisfy a modified scaling law in the remaining cases. Moreover, the total mass of aggregates depends strongly on the net birth rate g 1 (t) - g 2 (t) and evolves exponentially as exp{∫ t 0 [g 1 (t') - g 2 (t')] dt'}, which is in qualitative agreement with the evolution of the total population of a country in real world

  10. Juvenile Arthritis

    Science.gov (United States)

    Juvenile arthritis (JA) is arthritis that happens in children. It causes joint swelling, pain, stiffness, and loss of motion. It can affect any joint, but ... of JA that children get is juvenile idiopathic arthritis. There are several other forms of arthritis affecting ...

  11. Interactive effects of food quality, temperature and rearing time on condition of juvenile black bream Acanthopagrus butcheri.

    Science.gov (United States)

    Walther, B D; Elsdon, T S; Gillanders, B M

    2010-06-01

    A laboratory experiment was conducted to determine the interactive effects of temperature and diet on condition indices of juvenile black bream Acanthopagrus butcheri, reared for time periods ranging from 2 to 42 days. After fish were reared for varying periods, growth, morphometric (Fulton's K) and biochemical [RNA:DNA (R:D) ratios] indices were measured. Fulton's K responded primarily to temperature, with progressive decrease in condition over time for fish reared at high temperatures. In contrast, R:D ratios were primarily affected by diet composition, with the highest values observed for fish reared on fish-based diets as opposed to vegetable-based diets. Significant effects of rearing time were also observed for Fulton's K and R:D ratios, as were some interactive treatment effects. In addition, Fulton's K and R:D ratios were not significantly correlated, perhaps due to the different periods of time integrated by each index or their relative sensitivity to lipid and protein deposition. These results highlight the complex responses of these condition indices to environmental variables and nutritional status.

  12. Rapid expansion and pseudo spectral implementation for reverse time migration in VTI media

    KAUST Repository

    Pestana, Reynam C; Ursin, Bjø rn; Stoffa, Paul L

    2012-01-01

    In isotropic media, we use the scalar acoustic wave equation to perform reverse time migration (RTM) of the recorded pressure wavefield data. In anisotropic media, P- and SV-waves are coupled, and the elastic wave equation should be used for RTM. For computational efficiency, a pseudo-acoustic wave equation is often used. This may be solved using a coupled system of second-order partial differential equations. We solve these using a pseudo spectral method and the rapid expansion method (REM) for the explicit time marching. This method generates a degenerate SV-wave in addition to the P-wave arrivals of interest. To avoid this problem, the elastic wave equation for vertical transversely isotropic (VTI) media can be split into separate wave equations for P- and SV-waves. These separate wave equations are stable, and they can be effectively used to model and migrate seismic data in VTI media where |ε- δ| is small. The artifact for the SV-wave has also been removed. The independent pseudo-differential wave equations can be solved one for each mode using the pseudo spectral method for the spatial derivatives and the REM for the explicit time advance of the wavefield. We show numerically stable and high-resolution modeling and RTM results for the pure P-wave mode in VTI media. © 2012 Sinopec Geophysical Research Institute.

  13. Rapid expansion and pseudo spectral implementation for reverse time migration in VTI media

    KAUST Repository

    Pestana, Reynam C

    2012-04-24

    In isotropic media, we use the scalar acoustic wave equation to perform reverse time migration (RTM) of the recorded pressure wavefield data. In anisotropic media, P- and SV-waves are coupled, and the elastic wave equation should be used for RTM. For computational efficiency, a pseudo-acoustic wave equation is often used. This may be solved using a coupled system of second-order partial differential equations. We solve these using a pseudo spectral method and the rapid expansion method (REM) for the explicit time marching. This method generates a degenerate SV-wave in addition to the P-wave arrivals of interest. To avoid this problem, the elastic wave equation for vertical transversely isotropic (VTI) media can be split into separate wave equations for P- and SV-waves. These separate wave equations are stable, and they can be effectively used to model and migrate seismic data in VTI media where |ε- δ| is small. The artifact for the SV-wave has also been removed. The independent pseudo-differential wave equations can be solved one for each mode using the pseudo spectral method for the spatial derivatives and the REM for the explicit time advance of the wavefield. We show numerically stable and high-resolution modeling and RTM results for the pure P-wave mode in VTI media. © 2012 Sinopec Geophysical Research Institute.

  14. Analytical reverse time migration: An innovation in imaging of infrastructures using ultrasonic shear waves.

    Science.gov (United States)

    Asadollahi, Aziz; Khazanovich, Lev

    2018-04-11

    The emergence of ultrasonic dry point contact (DPC) transducers that emit horizontal shear waves has enabled efficient collection of high-quality data in the context of a nondestructive evaluation of concrete structures. This offers an opportunity to improve the quality of evaluation by adapting advanced imaging techniques. Reverse time migration (RTM) is a simulation-based reconstruction technique that offers advantages over conventional methods, such as the synthetic aperture focusing technique. RTM is capable of imaging boundaries and interfaces with steep slopes and the bottom boundaries of inclusions and defects. However, this imaging technique requires a massive amount of memory and its computation cost is high. In this study, both bottlenecks of the RTM are resolved when shear transducers are used for data acquisition. An analytical approach was developed to obtain the source and receiver wavefields needed for imaging using reverse time migration. It is shown that the proposed analytical approach not only eliminates the high memory demand, but also drastically reduces the computation time from days to minutes. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Decoupled equations for reverse time migration in tilted transversely isotropic media

    KAUST Repository

    Zhan, Ge; Pestana, Reynam C.; Stoffa, Paul L.

    2012-01-01

    Conventional modeling and migration for tilted transversely isotropic (TTI) media may suffer from numerical instabilities and shear wave artifacts due to the coupling of the P-wave and SV-wave modes in the TTI coupled equations. Starting with the separated P- and SV-phase velocity expressions for vertical transversely isotropic (VTI) media, we extend these decoupled equations for modeling and reverse time migration (RTM) in acoustic TTI media. Compared with the TTI coupled equations published in the geophysical literature, the new TTI decoupled equations provide a more stable solution due to the complete separation of the P-wave and SV-wave modes. The pseudospectral method is the most convenient method to implement these equations due to the form of wavenumber expressions and has the added benefit of being highly accurate and thus avoiding numerical dispersion. The rapid expansion method (REM) in time is employed to produce a broad band numerically stable time evolution of the wavefields. Synthetic results validate the proposed TTI decoupled equations and show that modeling and RTM in TTI media with the decoupled equations remain numerically stable even for models with strong anisotropy and sharp contrasts. © 2012 Society of Exploration Geophysicists.

  16. Decoupled equations for reverse time migration in tilted transversely isotropic media

    KAUST Repository

    Zhan, Ge

    2012-03-01

    Conventional modeling and migration for tilted transversely isotropic (TTI) media may suffer from numerical instabilities and shear wave artifacts due to the coupling of the P-wave and SV-wave modes in the TTI coupled equations. Starting with the separated P- and SV-phase velocity expressions for vertical transversely isotropic (VTI) media, we extend these decoupled equations for modeling and reverse time migration (RTM) in acoustic TTI media. Compared with the TTI coupled equations published in the geophysical literature, the new TTI decoupled equations provide a more stable solution due to the complete separation of the P-wave and SV-wave modes. The pseudospectral method is the most convenient method to implement these equations due to the form of wavenumber expressions and has the added benefit of being highly accurate and thus avoiding numerical dispersion. The rapid expansion method (REM) in time is employed to produce a broad band numerically stable time evolution of the wavefields. Synthetic results validate the proposed TTI decoupled equations and show that modeling and RTM in TTI media with the decoupled equations remain numerically stable even for models with strong anisotropy and sharp contrasts. © 2012 Society of Exploration Geophysicists.

  17. Wide-azimuth angle-domain imaging for anisotropic reverse-time migration

    KAUST Repository

    Sava, Paul C.; Alkhalifah, Tariq Ali

    2011-01-01

    Extended common-image-point gathers (CIP) constructed by wide-azimuth TI wave-equation migration contain all the necessary information for angle decomposition as a function of the reflection and azimuth angles at selected locations in the subsurface. The reflection and azimuth angles are derived from the extended images using analytic relations between the space-lag and time-lag extensions. This post-imaging decomposition requires only information which is already available at the time of migration, i.e. the model parameters and the tilt angles of the TI medium. The transformation amounts to a linear Radon transform applied to the CIPs obtained after the application of the extended imaging condition. If information about the reflector dip is available at the CIP locations, then only two components of the space-lag vectors are required, thus reducing computational cost and increasing the affordability of the method. This efficient angle decomposition method is suitable for wide-azimuth imaging in anisotropic media with arbitrary orientation of the symmetry plane. © 2011 Society of Exploration Geophysicists.

  18. Wind conditions and geography shape the first outbound migration of juvenile honey buzzards and their distribution across sub-Saharan Africa.

    Science.gov (United States)

    Vansteelant, W M G; Kekkonen, J; Byholm, P

    2017-05-31

    Contemporary tracking studies reveal that low migratory connectivity between breeding and non-breeding ranges is common in migrant landbirds. It is unclear, however, how internal factors and early-life experiences of individual migrants shape the development of their migration routes and concomitant population-level non-breeding distributions. Stochastic wind conditions and geography may determine whether and where migrants end up by the end of their journey. We tested this hypothesis by satellite-tagging 31 fledgling honey buzzards Pernis apivorus from southern Finland and used a global atmospheric reanalysis model to estimate the wind conditions they encountered on their first outbound migration. Migration routes diverged rapidly upon departure and the birds eventually spread out across 3340 km of longitude. Using linear regression models, we show that the birds' longitudinal speeds were strongly affected by zonal wind speed, and negatively affected by latitudinal wind, with significant but minor differences between individuals. Eventually, 49% of variability in the birds' total longitudinal displacements was accounted for by wind conditions on migration. Some birds circumvented the Baltic Sea via Scandinavia or engaged in unusual downwind movements over the Mediterranean, which also affected the longitude at which these individuals arrived in sub-Saharan Africa. To understand why adult migrants use the migration routes and non-breeding sites they use, we must take into account the way in which wind conditions moulded their very first journeys. Our results present some of the first evidence into the mechanisms through which low migratory connectivity emerges. © 2017 The Authors.

  19. Time-dependent particle migration and margination in the pressure-driven channel flow of blood

    Science.gov (United States)

    Qi, Qin M.; Shaqfeh, Eric S. G.

    2018-03-01

    We present a theory to describe the time evolution of the red blood cell (RBC) and platelet concentration distributions in pressure-driven flow through a straight channel. This model is based on our previous theory for the steady-state distributions [Qi and Shaqfeh, Phys. Rev. Fluids 2, 093102 (2017), 10.1103/PhysRevFluids.2.093102] and captures the flow-induced nonuniformity of the concentrations of RBCs and platelets in the cross-flow direction. Starting with a uniform concentration, RBCs migrate away from the channel walls due to a shear-induced lift force and eventually reach steady state due to shear-induced diffusion, i.e., hydrodynamic "collisions" with other RBCs. On the other hand, platelets exit the cell-laden region due to RBC-platelet interactions and enter the cell-free layer, resulting in margination. To validate the theory, we also perform boundary integral simulations of blood flow in microchannels and directly compare various measureables between theory and simulation. The timescales associated with RBC migration and platelet margination are discussed in the context of the simulation and theory, and their importance in the function of microfluidic devices as well as the vascular network are elucidated. Due to the varying shear rate in pressure-driven flow and the wall-induced RBC lift, we report a separation of timescales for the transport in the near-wall region and in the bulk region. We also relate the transient problem to the axial variation of migration and margination, and we demonstrate how the relevant timescales can be used to predict corresponding entrance lengths. Our theory can serve as a fast and convenient alternative to large-scale simulations of these phenomena.

  20. Comparison of source moment tensor recovered by diffraction stacking migration and source time reversal imaging

    Science.gov (United States)

    Zhang, Q.; Zhang, W.

    2017-12-01

    Diffraction stacking migration is an automatic location methods and widely used in microseismic monitoring of the hydraulic fracturing. It utilizes the stacking of thousands waveform to enhance signal-to-noise ratio of weak events. For surface monitoring, the diffraction stacking method is suffered from polarity reverse among receivers due to radiation pattern of moment source. Joint determination of location and source mechanism has been proposed to overcome the polarity problem but needs significantly increased computational calculations. As an effective method to recover source moment tensor, time reversal imaging based on wave equation can locate microseismic event by using interferometry on the image to extract source position. However, the time reversal imaging is very time consuming compared to the diffraction stacking location because of wave-equation simulation.In this study, we compare the image from diffraction stacking and time reversal imaging to check if the diffraction stacking can obtain similar moment tensor as time reversal imaging. We found that image produced by taking the largest imaging value at each point along time axis does not exhibit the radiation pattern, while with the same level of calculation efficiency, the image produced for each trial origin time can generate radiation pattern similar to time reversal imaging procedure. Thus it is potential to locate the source position by the diffraction stacking method for general moment tensor sources.

  1. Juvenile Firesetting.

    Science.gov (United States)

    Peters, Brittany; Freeman, Bradley

    2016-01-01

    Juvenile firesetting is a significant cause of morbidity and mortality in the United States. Male gender, substance use, history of maltreatment, interest in fire, and psychiatric illness are commonly reported risk factors. Interventions that have been shown to be effective in juveniles who set fires include cognitive behavior therapy and educational interventions, whereas satiation has not been shown to be an effective intervention. Forensic assessments can assist the legal community in adjudicating youth with effective interventions. Future studies should focus on consistent assessment and outcome measures to create more evidence for directing evaluation and treatment of juvenile firesetters. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. The “Humanitarian” Corridor: A state of exception in times of global migration

    Directory of Open Access Journals (Sweden)

    Neža Kogovšek Šalamon

    2016-06-01

    Full Text Available The purpose of the article is to analyse the migration corridor managed by the state authorities on the Balkan migration route in the second half of 2015, understand it from the perspective of the existing legal and institutional frameworks, and show that the corridor was a phenomenon outside of national and European positive law, while at the same time it responded to the requirements of international human rights principles. The corridor was a clear, intentional and coordinated deviation from legal provisions. It amounted to a state of exception, a certain level of state of emergency in which the rules adopted by the national and European legislatures were suspended and replaced by internal instructions or decrees, or even with constantly changing state practices. The analysis involved comparison of a positive normative framework with the actual procedures carried out by the state structures, and identification of discrepancies which were then qualitatively evaluated from the perspective of international standards. Another purpose of the article was to show that the corridor which was also sometimes referred to as a “humanitarian corridor”, only seemed humanitarian since in fact it served a completely different purpose, namely the interests of state authorities for the refugees and migrants to leave their territories as quickly as possible.

  3. Differential timing and latitudinal variation in sex ratio of Aquatic Warblers during the autumn migration

    Science.gov (United States)

    Wojczulanis-Jakubas, Katarzyna; Chrostek, Małgorzata E.; Jiguet, Frédéric; Martínez, Carlos Zumalacárregui; Miguélez, David; Neto, Júlio M.

    2017-12-01

    Differential migration has been extensively reported in spring, but less so in autumn, particularly in relation to sex in monomorphic bird species. Here, we analysed the autumn passage of a monomorphic, globally threatened passerine, the Aquatic Warbler Acrocephalus paludicola throughout Western Europe, with regard to age and sex. We showed that, overall, adults migrated earlier than first-year birds, and males migrated earlier than females during the autumn migration. This may be caused by an overall social dominance of adults over immatures, and differentiated migration strategy of males and females. In addition, we found male-skewed sex proportions, with a tendency to an equalised ratio in more southern stopover sites. This may indicate a male bias in the global population or different migration strategies of the sexes. Differential migration may cause the age and sex classes to be exposed differently to various threats affecting demographic structure of the species.

  4. Juvenile Prostitution.

    Science.gov (United States)

    Csapo, Marg

    1986-01-01

    Recent research and Canadian government committee reports concerning juvenile prostitution are reviewed. Proposals are made in the realms of law and social policy; and existing programs are described. (DB)

  5. Timing of seasonal migration in mule deer: effects of climate, plant phenology, and life-history characteristics

    Science.gov (United States)

    Monteith, Kevin L.; Bleich, Vernon C.; Stephenson, Thomas R.; Pierce, Beck M.; Conner, Mary M.; Klaver, Robert W.; Bowyer, R. Terry

    2011-01-01

    Phenological events of plants and animals are sensitive to climatic processes. Migration is a life-history event exhibited by most large herbivores living in seasonal environments, and is thought to occur in response to dynamics of forage and weather. Decisions regarding when to migrate, however, may be affected by differences in life-history characteristics of individuals. Long-term and intensive study of a population of mule deer (Odocoileus hemionus) in the Sierra Nevada, California, USA, allowed us to document patterns of migration during 11 years that encompassed a wide array of environmental conditions. We used two new techniques to properly account for interval-censored data and disentangle effects of broad-scale climate, local weather patterns, and plant phenology on seasonal patterns of migration, while incorporating effects of individual life-history characteristics. Timing of autumn migration varied substantially among individual deer, but was associated with the severity of winter weather, and in particular, snow depth and cold temperatures. Migratory responses to winter weather, however, were affected by age, nutritional condition, and summer residency of individual females. Old females and those in good nutritional condition risked encountering severe weather by delaying autumn migration, and were thus risk-prone with respect to the potential loss of foraging opportunities in deep snow compared with young females and those in poor nutritional condition. Females that summered on the west side of the crest of the Sierra Nevada delayed autumn migration relative to east-side females, which supports the influence of the local environment on timing of migration. In contrast, timing of spring migration was unrelated to individual life-history characteristics, was nearly twice as synchronous as autumn migration, differed among years, was related to the southern oscillation index, and was influenced by absolute snow depth and advancing phenology of plants

  6. Incoherent dictionary learning for reducing crosstalk noise in least-squares reverse time migration

    Science.gov (United States)

    Wu, Juan; Bai, Min

    2018-05-01

    We propose to apply a novel incoherent dictionary learning (IDL) algorithm for regularizing the least-squares inversion in seismic imaging. The IDL is proposed to overcome the drawback of traditional dictionary learning algorithm in losing partial texture information. Firstly, the noisy image is divided into overlapped image patches, and some random patches are extracted for dictionary learning. Then, we apply the IDL technology to minimize the coherency between atoms during dictionary learning. Finally, the sparse representation problem is solved by a sparse coding algorithm, and image is restored by those sparse coefficients. By reducing the correlation among atoms, it is possible to preserve most of the small-scale features in the image while removing much of the long-wavelength noise. The application of the IDL method to regularization of seismic images from least-squares reverse time migration shows successful performance.

  7. Multisource least-squares reverse-time migration with structure-oriented filtering

    Science.gov (United States)

    Fan, Jing-Wen; Li, Zhen-Chun; Zhang, Kai; Zhang, Min; Liu, Xue-Tong

    2016-09-01

    The technology of simultaneous-source acquisition of seismic data excited by several sources can significantly improve the data collection efficiency. However, direct imaging of simultaneous-source data or blended data may introduce crosstalk noise and affect the imaging quality. To address this problem, we introduce a structure-oriented filtering operator as preconditioner into the multisource least-squares reverse-time migration (LSRTM). The structure-oriented filtering operator is a nonstationary filter along structural trends that suppresses crosstalk noise while maintaining structural information. The proposed method uses the conjugate-gradient method to minimize the mismatch between predicted and observed data, while effectively attenuating the interference noise caused by exciting several sources simultaneously. Numerical experiments using synthetic data suggest that the proposed method can suppress the crosstalk noise and produce highly accurate images.

  8. Progress in the migration towards the real-time framework MARTe at the FTU tokamak

    International Nuclear Information System (INIS)

    Boncagni, L.; Sadeghi, Y.; Vitelli, R.; Centioli, C.; Sinibaldi, S.; Vitale, V.; Zaccarian, L.; Zamborlini, G.

    2011-01-01

    Keeping in mind the proposed FAST experiment and aiming to meet basic requirements such as a modular and distributed architecture, where different control subsystems can be easily integrated at different times, and can operate either independently or in cooperation with other subsystems, at the end of last year we planned to upgrade the architecture of the FTU real-time system, improving in such a way its flexibility and modularity. We decided to adopt an available packages to reach our goal: MARTe. We report on the state of the art of the MARTe migration process, the difficulties dealt with, the benefits and advantages achieved, the progress made from our last report and, in particular, we describe the integration of the ODIN equilibrium reconstruction system in the real-time environment. The ODIN algorithm was already coded in previous works, but its integration in the real-time system has never been carried out at FTU. We illustrate how the MARTe architecture and the RTNet level allows for a first level of parallelization, distributing the data and/or time among nodes.

  9. Progress in the migration towards the real-time framework MARTe at the FTU tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Boncagni, L., E-mail: boncagni@frascati.enea.it [Associazione EURATOM-ENEA sulla Fusione, C.R. ENEA Frascati, Rome (Italy); Sadeghi, Y.; Vitelli, R. [Dipartimento di Informatica, Sistemi e Produzione, Universita di Roma, Tor Vergata, Rome (Italy); Centioli, C. [Associazione EURATOM-ENEA sulla Fusione, C.R. ENEA Frascati, Rome (Italy); Sinibaldi, S. [Dipartimento di Informatica, Sistemi e Produzione, Universita di Roma, Tor Vergata, Rome (Italy); Vitale, V. [Associazione EURATOM-ENEA sulla Fusione, C.R. ENEA Frascati, Rome (Italy); Zaccarian, L. [Dipartimento di Informatica, Sistemi e Produzione, Universita di Roma, Tor Vergata, Rome (Italy); Zamborlini, G. [Facolta di Ingegneria, Universita di Roma La Sapienza, Rome (Italy)

    2011-10-15

    Keeping in mind the proposed FAST experiment and aiming to meet basic requirements such as a modular and distributed architecture, where different control subsystems can be easily integrated at different times, and can operate either independently or in cooperation with other subsystems, at the end of last year we planned to upgrade the architecture of the FTU real-time system, improving in such a way its flexibility and modularity. We decided to adopt an available packages to reach our goal: MARTe. We report on the state of the art of the MARTe migration process, the difficulties dealt with, the benefits and advantages achieved, the progress made from our last report and, in particular, we describe the integration of the ODIN equilibrium reconstruction system in the real-time environment. The ODIN algorithm was already coded in previous works, but its integration in the real-time system has never been carried out at FTU. We illustrate how the MARTe architecture and the RTNet level allows for a first level of parallelization, distributing the data and/or time among nodes.

  10. In Vivo Real-Time Imaging of Exogenous HGF-Triggered Cell Migration in Rat Intact Soleus Muscles

    International Nuclear Information System (INIS)

    Ishido, Minenori; Kasuga, Norikatsu

    2012-01-01

    The transplantation of myogenic cells is a potentially effective therapy for muscular dystrophy. However, this therapy has achieved little success because the diffusion of transplanted myogenic cells is limited. Hepatocyte growth factor (HGF) is one of the primary triggers to induce myogenic cell migration in vitro. However, to our knowledge, whether exogenous HGF can trigger the migration of myogenic cells (i.e. satellite cells) in intact skeletal muscles in vivo has not been reported. We previously reported a novel in vivo real-time imaging method in rat skeletal muscles. Therefore, the present study examined the relationship between exogenous HGF treatment and cell migration in rat intact soleus muscles using this imaging method. As a result, it was indicated that the cell migration velocity was enhanced in response to increasing exogenous HGF concentration in skeletal muscles. Furthermore, the expression of MyoD was induced in satellite cells in response to HGF treatment. We first demonstrated in vivo real-time imaging of cell migration triggered by exogenous HGF in intact soleus muscles. The experimental method used in the present study will be a useful tool to understand further the regulatory mechanism of HGF-induced satellite cell migration in skeletal muscles in vivo

  11. Village level inequality, migration and remittances in rural Mexico: How do they change over time?

    OpenAIRE

    Aslihan Arslan; J. Edward Taylor

    2010-01-01

    We analyze how migration prevalence and remittances shape income distribution using novel panel data that is nationally and regionally representative of rural Mexico. Employing a Gini decomposition and controlling for whole household migration (attrition), we find that migration prevalence has increased between 2002 and 2007 reversing the unequalizing effects of international remittances at the national level. We also analyze regional differences in the effects of remittances on inequality, a...

  12. Growth performance of pearl goldfish juvenile carassius auratus cultured in 3 ppt salinity with different exposure time of electric field

    Directory of Open Access Journals (Sweden)

    Kukuh Nirmala

    2015-04-01

    Full Text Available ABSTRACTGrowth rate of pearl goldfish juvenile Carassius auratus relatively slow to reach market size which will take approximately three months. To accelerate its growth can be done by providing exposure of the fish to low-power electric fields (10 V via 3 ppt salinity water, with the goal of providing the close isoosmotic conditions, and also to streamline the flow of electricity from the electrodes to the body of the fish. This study aims to calculate the survival and growth rate of pearl goldfish juvenile of S sizes (2‒4 cm of body length which were maintained at 3 ppt salinity water and treated by different exposure time of electric field (zero, two, four, and six minutes before feeding with 10 volt electric power. Fish were cultured at a density of 2 fish/L in the (20×30×20 cm3 aquaria in volume of 6 L of water. Test fish had an average body length of 4.11±0.05 cm and the average body weight of 2.89±0.05 g. Exposure time of electric field were zero, two, four, and six minutes before the fish are fed, performed every day as much as three times i.e. morning, afternoon, and evening. The research design used was completely randomized design with four treatments, namely 0, 2, 4, and 6 (time for exposure is zero/control, two, four, and six minute with three replications. The results show test fishes exposed to 10 volt electrical field for zero, two, four, and six minutes, have no significant effect on survival rate (P>0.05. For growth performance, four minute exposure treatment gives the best results compared to controls (P<0.05, supported by an increase in the percentage of the ratio of gut length to body length of the fish and higher feed efficiency.Keywords: long exposure to the electric field, growth performance, pearl goldfishABSTRAKPertumbuhan benih ikan hias maskoki mutiara Carassius auratus relatif lambat, karena untuk mencapai ukuran jual memerlukan waktu sekitar tiga bulan. Untuk mempercepat pertumbuhannya dapat dilakukan dengan

  13. Rapid expansion method (REM) for time‐stepping in reverse time migration (RTM)

    KAUST Repository

    Pestana, Reynam C.

    2009-01-01

    We show that the wave equation solution using a conventional finite‐difference scheme, derived commonly by the Taylor series approach, can be derived directly from the rapid expansion method (REM). After some mathematical manipulation we consider an analytical approximation for the Bessel function where we assume that the time step is sufficiently small. From this derivation we find that if we consider only the first two Chebyshev polynomials terms in the rapid expansion method we can obtain the second order time finite‐difference scheme that is frequently used in more conventional finite‐difference implementations. We then show that if we use more terms from the REM we can obtain a more accurate time integration of the wave field. Consequently, we have demonstrated that the REM is more accurate than the usual finite‐difference schemes and it provides a wave equation solution which allows us to march in large time steps without numerical dispersion and is numerically stable. We illustrate the method with post and pre stack migration results.

  14. Liquid culture mass production of biocontrol nematodes, Heterorhabditis bacteriophora (Nematoda: Rhabditida): improved timing of dauer juvenile inoculation.

    Science.gov (United States)

    Johnigk, S-A; Ecke, F; Poehling, M; Ehlers, R-U

    2004-06-01

    Heterorhabditis bacteriophora is used in biological control of soil-borne insect pests in horticulture and turf. Mass production is carried out in monoxenic liquid cultures pre-incubated with the symbiont of the nematodes, the bacterium Photorhabdus luminescens, before nematode dauer juveniles (DJ) are inoculated. As a response to bacterial food signals, the DJ recover from the developmentally arrested dauer stage, grow to adults and produce DJ offspring. Variable DJ recovery after inoculation into cultures of P. luminescens often causes process failure due to low numbers of adult nematodes in the medium. In order to enhance DJ recovery, improve nematode population management and increase yields, the optimal timing for DJ inoculation was sought. The process parameter pH and respiration quotient (RQ) were recorded in order to test whether changes can be used to identify the best moment for DJ inoculation. When DJ were inoculated during the lag and early logarithmic growth phases of P. luminescens cultures, DJ recovery was low and almost no nematode reproduction was obtained. High populations of P. luminescens phase variants were recorded. Recovery and yields increased when DJ were inoculated during the latter log phase during which the RQ dropped to values <0.8 and the pH reached a maximum. The highest DJ recovery and yields were observed in cultures that were inoculated during the late stationary growth phase. This period started with the increase of the pH after its distinct minimum at pH <8.0. Thus optimal timing for DJ inoculation can be defined through monitoring of the pH in the P. luminescens culture.

  15. The POU Factor Ventral Veins Lacking/Drifter Directs the Timing of Metamorphosis through Ecdysteroid and Juvenile Hormone Signaling

    Science.gov (United States)

    Chaieb, Leila; Koyama, Takashi; Sarwar, Prioty; Mirth, Christen K.; Smith, Wendy A.; Suzuki, Yuichiro

    2014-01-01

    Although endocrine changes are known to modulate the timing of major developmental transitions, the genetic mechanisms underlying these changes remain poorly understood. In insects, two developmental hormones, juvenile hormone (JH) and ecdysteroids, are coordinated with each other to induce developmental changes associated with metamorphosis. However, the regulation underlying the coordination of JH and ecdysteroid synthesis remains elusive. Here, we examined the function of a homolog of the vertebrate POU domain protein, Ventral veins lacking (Vvl)/Drifter, in regulating both of these hormonal pathways in the red flour beetle, Tribolium castaneum (Tenebrionidae). RNA interference-mediated silencing of vvl expression led to both precocious metamorphosis and inhibition of molting in the larva. Ectopic application of a JH analog on vvl knockdown larvae delayed the onset of metamorphosis and led to a prolonged larval stage, indicating that Vvl acts upstream of JH signaling. Accordingly, vvl knockdown also reduced the expression of a JH biosynthesis gene, JH acid methyltransferase 3 (jhamt3). In addition, ecdysone titer and the expression of the ecdysone response gene, hormone receptor 3 (HR3), were reduced in vvl knockdown larvae. The expression of the ecdysone biosynthesis gene phantom (phm) and spook (spo) were reduced in vvl knockdown larvae in the anterior and posterior halves, respectively, indicating that Vvl might influence ecdysone biosynthesis in both the prothoracic gland and additional endocrine sources. Injection of 20-hydroxyecdysone (20E) into vvl knockdown larvae could restore the expression of HR3 although molting was never restored. These findings suggest that Vvl coordinates both JH and ecdysteroid biosynthesis as well as molting behavior to influence molting and the timing of metamorphosis. Thus, in both vertebrates and insects, POU factors modulate the production of major neuroendocrine regulators during sexual maturation. PMID:24945490

  16. Reverse-time Migration in Tilted Transversely Isotropic Media with Decoupled Equations

    KAUST Repository

    Zhan, Ge

    2012-12-01

    Conventional modeling and migration for tilted transversely isotropic (TTI) media may suffer from numerical instabilities and shear wave artifacts due to the coupling of the P-wave and SV-wave modes in the TTI coupled equations. Starting with the separated P- and SV-phase velocity expressions for vertical transversely isotropic (VTI) media, I extend these decoupled equations for modeling and reverse-time migration (RTM) in acoustic TTI media. Compared with the TTI coupled equations published in the geophysical literature, the new TTI decoupled equations provide a more stable solution due to the complete separation of the P-wave and SV-wave modes. The pseudospectral (PS) method is the most convenient method to implement these equations due to the form of wavenumber expressions and has the added benefit of being highly accurate and thus avoiding numerical dispersion. The rapid expansion method (REM) in time is employed to produce a broad band numerically stable time evolution of the wavefields. Synthetic results validate the proposed TTI decoupled equations and show that modeling and RTM in TTI media with the decoupled P-wave equation remain numerically stable even for models with strong anisotropy and sharp contrasts. The most desirable feature of the TTI decoupled P-wave equation is that it is absolutely free of shear-wave artifacts and the consequent alleviation of numerical instabilities generally suffered by some systems of coupled equations. However, due to several forward-backward Fourier transforms in wavefield extrapolation at each time step, the computational cost is also high, and thereby hampers its prevalence. I hereby propose to use a hybrid pseudospectral and finite-difference (FD) scheme to solve the TTI decoupled P-wave equation. In the hybrid solution, most of the cost-consuming wavenumber terms in the equation are replaced by inexpensive FD operators, which in turn accelerates the computation and reduces the computational cost. To demonstrate the

  17. Behavior and potential threats to survival of migrating lamprey ammocoetes and macrophthalmia

    Energy Technology Data Exchange (ETDEWEB)

    Moser, Mary L.; Jackson, Aaron D.; Lucas, Martyn C.; Mueller, Robert P.

    2015-03-01

    Upon metamorphosis, anadromous juvenile lamprey (macrophthalmia) exhibit distinct migration behaviors that take them from larval rearing habitats in streams to the open ocean. While poorly studied, lamprey larvae (ammocoetes) also engage in downstream movement to some degree. Like migrating salmon smolts, lamprey macrophthalmia undergo behavioral changes associated with a highly synchronized metamorphosis. Unlike salmon smolts, the timing of juvenile migration in lamprey is protracted and poorly documented. Lamprey macrophthalmia and ammocoetes are not strong swimmers, attaining maximum individual speeds of less than 1 m s-1, and sustained speeds of less than 0.5 m s-1. They are chiefly nocturnal and distribute throughout the water column, but appear to concentrate near the bottom in the thalweg of deep rivers. At dams and irrigation diversions, macrophthalmia can become impinged on screens or entrained in irrigation canals, suffer increased predation, and experience physical injury that may result in direct or delayed mortality. The very structures designed to protect migrating juvenile salmonids can be harmful to juvenile lamprey. Yet at turbine intakes and spillways, lampreys, which have no swim bladder, can withstand changes in pressure and shear stress large enough to injure or kill most teleosts. Lamprey populations are in decline in many parts of the world, with some species designated as species of concern for conservation that merit legally mandated protections. Hence, provisions for safe passage of juvenile lamprey are being considered at dams and water diversions in North America and Europe.

  18. Timely Diagnosis of Malalignment of the Distal Extremities Is Crucial in Morbidly Obese Juveniles

    Directory of Open Access Journals (Sweden)

    Franz Landauer

    2013-12-01

    Full Text Available Background/Aims: To determine i whether obesity in childhood can be related to malalignment of the distal extremities, ii the proportion of genu valgum malalignment and abduction setting, and iii the respective deviation dominance in children who are morbidly obese. Methods: 31 morbidly obese Caucasian children (16 males recruited for the STYJOBS Study (ClinicalTrials.gov Identifier NCT00482924 with a mean age of 13.9 ± 0.5 years, a mean height of 162.3 ± 2.7 cm, a mean weight of 90.62 ± 5.0 kg, and a mean BMI of 33.8 ± 1.2 kg/m2 were clinically examined using the Mikulicz line in order to assess load distribution on the knee joint. 21 participants received a whole-leg X-ray because of a clinically estimated malalignment. Results: 8/31 participants examined were diagnosed with genu valgum, 1/31 with genu varum, and 22/31 did not have any malalignment of the femur or tibia. The majority of genu valgum presentation was due to femoral deviation. Of those without malalignment, 4/22 participants had an abduction setting, while 2/22 showed an adduction of the leg. Conclusion: Genu valgum as a predominant malalignment of the distal extremities is frequent in youth with morbid obesity. Timely guided correction of angular deformity of the knee seems pivotal in order to avoid osteotomy or osteoarthritis later in life.

  19. SUPPRESSING DIFFRACTION EFFECT USING KIRCHHOFF PRE-STACK TIME MIGRATION ON 2D SEISMIC MULTICHANNEL DATA AT FLORES SEA

    Directory of Open Access Journals (Sweden)

    Tumpal Benhard Nainggolan

    2017-07-01

    Full Text Available 2D seismic multichannel survey has been carried out by Marine Geological Institute of Indonesia to interpret imaging and sub-surface geological information in the Flores Sea. Seismic data processing starts from pre-processing until migration stage. Migration is an important stage in the seismic processing, because at this stage the effects of diffraction and oblique reflectors caused by fault, salt domes, wedging, etc. will be repositioned to the actual points. One example of diffraction effects can be seen on the seismic section of a conventional stacking that have not migrated, i.e. resulting in an apparent bowtie reflector. Geologists find difficulties in interpreting geological information from diffracted seismic section, so it needs further processing to overcome the effects. By using Kirchhoff method and carried out during the Pre-Stack Time Migration (PSTM, this method turns out to produce migrated seismic section which is much better than conventional stacked one. This is due to the Kirchhoff method suppressed the identified diffraction effects, so that the geologist can interpret geological structure of the resulting migrated seismic section of the Flores Sea.

  20. Size-selective sorting in bubble streaming flows: Particle migration on fast time scales

    Science.gov (United States)

    Thameem, Raqeeb; Rallabandi, Bhargav; Hilgenfeldt, Sascha

    2015-11-01

    Steady streaming from ultrasonically driven microbubbles is an increasingly popular technique in microfluidics because such devices are easily manufactured and generate powerful and highly controllable flows. Combining streaming and Poiseuille transport flows allows for passive size-sensitive sorting at particle sizes and selectivities much smaller than the bubble radius. The crucial particle deflection and separation takes place over very small times (milliseconds) and length scales (20-30 microns) and can be rationalized using a simplified geometric mechanism. A quantitative theoretical description is achieved through the application of recent results on three-dimensional streaming flow field contributions. To develop a more fundamental understanding of the particle dynamics, we use high-speed photography of trajectories in polydisperse particle suspensions, recording the particle motion on the time scale of the bubble oscillation. Our data reveal the dependence of particle displacement on driving phase, particle size, oscillatory flow speed, and streaming speed. With this information, the effective repulsive force exerted by the bubble on the particle can be quantified, showing for the first time how fast, selective particle migration is effected in a streaming flow. We acknowledge support by the National Science Foundation under grant number CBET-1236141.

  1. Timing of pre-nuptial migration and leap-frog patterns in Yellow ...

    African Journals Online (AJOL)

    nuptial migration period, in parts of the wintering grounds most distant from the breeding area. Birds breeding at the highest latitudes are the latest to depart on prenuptial migration, and so can take advantage of this surge by extending their ...

  2. Upstream migration of Pacific lampreys in the John Day River, Oregon: Behavior, timing, and habitat use

    Science.gov (United States)

    Robinson, T. Craig; Bayer, J.M.

    2005-01-01

    Adult Pacific lamprey migration and habitat preferences for over-winter holding and spawning, and larval rearing in tributaries to the Columbia River are not well understood. The John Day River is one such tributary where larval and adult stages of this species have been documented, and its free-flowing character provided the opportunity to study migration of Pacific lampreys unimpeded by passage constraints. Forty-two adult Pacific lampreys were captured in the John Day River near its mouth during their upstream migration. Pacific lampreys were surgically implanted with radio transmitters and released onsite, and tracked by fixed-site, aerial, and terrestrial telemetry methods for nearly one year. Adults moved upstream exclusively at night, with a mean rate of 11.1 ?? 6.3 km/day. They halted upstream migration by September, and held a single position for approximately six months in the lateral margins of riffles and glides, using boulders for cover. More than half of Pacific lampreys resumed migration in March before ending movement in early May. Pacific lampreys that resumed migration in spring completed a median of 87% of their upstream migration before over-winter holding. Upon completing migration. Pacific lampreys briefly held position before beginning downstream movement at the end of May. Though not directly observed, halting migration and movement downstream were likely the result of spawning and death. Gains in adult Pacific lamprey passage through the Columbia River hydrosystem and tributaries may be made by improvements that would expedite migration during spring and summer and increase the quantity and variety of cover and refuge opportunities. ?? 2005 by the Northwest Scientific Association. All rights reserved.

  3. Imaging of first-order surface-related multiples by reverse-time migration

    Science.gov (United States)

    Liu, Xuejian; Liu, Yike; Hu, Hao; Li, Peng; Khan, Majid

    2017-02-01

    Surface-related multiples have been utilized in the reverse-time migration (RTM) procedures, and additional illumination for subsurface can be provided. Meanwhile, many cross-talks are generated from undesired interactions between forward- and backward-propagated seismic waves. In this paper, subsequent to analysing and categorizing these cross-talks, we propose RTM of first-order multiples to avoid most undesired interactions in RTM of all-order multiples, where only primaries are forward-propagated and crosscorrelated with the backward-propagated first-order multiples. With primaries and multiples separated during regular seismic data processing as the input data, first-order multiples can be obtained by a two-step scheme: (1) the dual-prediction of higher-order multiples; and (2) the adaptive subtraction of predicted higher-order multiples from all-order multiples within local offset-time windows. In numerical experiments, two synthetic and a marine field data sets are used, where different cross-talks generated by RTM of all-order multiples can be identified and the proposed RTM of first-order multiples can provide a very interpretable image with a few cross-talks.

  4. Microseismic imaging using Geometric-mean Reverse-Time Migration in Hydraulic Fracturing Monitoring

    Science.gov (United States)

    Yin, J.; Ng, R.; Nakata, N.

    2017-12-01

    Unconventional oil and gas exploration techniques such as hydraulic fracturing are associated with microseismic events related to the generation and development of fractures. For example, hydraulic fracturing, which is popular in Southern Oklahoma, produces earthquakes that are greater than magnitude 2.0. Finding the accurate locations, and mechanisms, of these events provides important information of local stress conditions, fracture distribution, hazard assessment, and economical impact. The accurate source location is also important to separate fracking-induced and wastewater disposal induced seismicity. Here, we implement a wavefield-based imaging method called Geometric-mean Reverse-Time Migration (GmRTM), which takes the advantage of accurate microseismic location based on wavefield back projection. We apply GmRTM to microseismic data collected during hydraulic fracturing for imaging microseismic source locations, and potentially, fractures. Assuming an accurate velocity model, GmRTM can improve the spatial resolution of source locations compared to HypoDD or P/S travel-time based methods. We will discuss the results from GmRTM and HypoDD using this field dataset and synthetic data.

  5. Juvenile angiofibromer

    DEFF Research Database (Denmark)

    Thuesen, Anne Daugaard; Jakobsen, John; Nepper-Rasmussen, Jørgen

    2005-01-01

    Juvenile angiofibroma is a rare, benign, rich vascular tumor, and approximately one new case is diagnosed in Denmark each year. It sits in the foramen sphenopalatinum and occurs in boys from 14 to 25 years of age. The most frequent initial symptoms are nasal obstruction and epistaxis. Through...... the years, the treatment of juvenile angiofibroma has included many methods, including surgical excision, electrocoagulation, interstitial or external radiation therapy, cryosurgery, hormone administration and chemotherapy. Radiation, chemotherapy and surgery have proven to be the most effective treatments...

  6. The Reverse Time Migration technique coupled with Interior Penalty Discontinuous Galerkin method.

    Science.gov (United States)

    Baldassari, C.; Barucq, H.; Calandra, H.; Denel, B.; Diaz, J.

    2009-04-01

    Seismic imaging is based on the seismic reflection method which produces an image of the subsurface from reflected waves recordings by using a tomography process and seismic migration is the industrial standard to improve the quality of the images. The migration process consists in replacing the recorded wavefields at their actual place by using various mathematical and numerical methods but each of them follows the same schedule, according to the pioneering idea of Claerbout: numerical propagation of the source function (propagation) and of the recorded wavefields (retropropagation) and next, construction of the image by applying an imaging condition. The retropropagation step can be realized accouting for the time reversibility of the wave equation and the resulting algorithm is currently called Reverse Time Migration (RTM). To be efficient, especially in three dimensional domain, the RTM requires the solution of the full wave equation by fast numerical methods. Finite element methods are considered as the best discretization method for solving the wave equation, even if they lead to the solution of huge systems with several millions of degrees of freedom, since they use meshes adapted to the domain topography and the boundary conditions are naturally taken into account in the variational formulation. Among the different finite element families, the spectral element one (SEM) is very interesting because it leads to a diagonal mass matrix which dramatically reduces the cost of the numerical computation. Moreover this method is very accurate since it allows the use of high order finite elements. However, SEM uses meshes of the domain made of quadrangles in 2D or hexaedra in 3D which are difficult to compute and not always suitable for complex topographies. Recently, Grote et al. applied the IPDG (Interior Penalty Discontinuous Galerkin) method to the wave equation. This approach is very interesting since it relies on meshes with triangles in 2D or tetrahedra in 3D

  7. Is there a connection between weather at departure sites, onset of migration and timing of soaring-bird autumn migration in Israel?

    NARCIS (Netherlands)

    Shamoun-Baranes, J.; van Loon, E.E.; Alon, D.; Alpert, P.; Yom-Tov, Y.; Leshem, Y.

    2006-01-01

    Aims Different aspects of soaring-bird migration are influenced by weather. However, the relationship between weather and the onset of soaring-bird migration, particularly in autumn, is not clear. Although long-term migration counts are often unavailable near the breeding areas of many soaring birds

  8. Common-image gathers in the offset domain from reverse-time migration

    KAUST Repository

    Zhan, Ge; Zhang, Minyu

    2014-01-01

    Kirchhoff migration is flexible to output common-image gathers (CIGs) in the offset domain by imaging data with different offsets separately. These CIGs supply important information for velocity model updates and amplitude-variation-with-offset (AVO

  9. Consistency in long-distance bird migration: contrasting patterns in time and space for two raptors

    NARCIS (Netherlands)

    Vardanis, Yannis; Nilsson, Jan-Ake; Klaassen, Raymond H. G.; Strandberg, Roine; Alerstam, Thomas

    As the evolutionary responses to environmental change depend on selection acting on individual differences, disentangling within- and between-individual variation becomes imperative. In animal migration research, multiyear tracks are thus needed to estimate the individual consistency of phenotypic

  10. GPU-accelerated element-free reverse-time migration with Gauss points partition

    Science.gov (United States)

    Zhou, Zhen; Jia, Xiaofeng; Qiang, Xiaodong

    2018-06-01

    An element-free method (EFM) has been demonstrated successfully in elasticity, heat conduction and fatigue crack growth problems. We present the theory of EFM and its numerical applications in seismic modelling and reverse time migration (RTM). Compared with the finite difference method and the finite element method, the EFM has unique advantages: (1) independence of grids in computation and (2) lower expense and more flexibility (because only the information of the nodes and the boundary of the concerned area is required). However, in EFM, due to improper computation and storage of some large sparse matrices, such as the mass matrix and the stiffness matrix, the method is difficult to apply to seismic modelling and RTM for a large velocity model. To solve the problem of storage and computation efficiency, we propose a concept of Gauss points partition and utilise the graphics processing unit to improve the computational efficiency. We employ the compressed sparse row format to compress the intermediate large sparse matrices and attempt to simplify the operations by solving the linear equations with CULA solver. To improve the computation efficiency further, we introduce the concept of the lumped mass matrix. Numerical experiments indicate that the proposed method is accurate and more efficient than the regular EFM.

  11. Diverse juvenile life-history behaviours contribute to the spawning stock of an anadromous fish population

    Science.gov (United States)

    Walsworth, Timothy E.; Schindler, Daniel E.; Griffiths, Jennifer R.; Zimmerman, Christian E.

    2015-01-01

    Habitat quality often varies substantially across space and time, producing a shifting mosaic of growth and mortality trade-offs across watersheds. Traditional studies of juvenile habitat use have emphasised the evolution of single optimal strategies that maximise recruitment to adulthood and eventual fitness. However, linking the distribution of individual behaviours that contribute to recruitment at the population level has been elusive, particularly for highly fecund aquatic organisms. We examined juvenile habitat use within a population of sockeye salmon (Oncorhynchus nerka) that spawn in a watershed consisting of two interconnected lakes and a marine lagoon. Otolith microchemical analysis revealed that the productive headwater lake accounted for about half of juvenile growth for those individuals surviving to spawn in a single river in the upper watershed. However, 47% of adults had achieved more than half of their juvenile growth in the downstream less productive lake, and 3% of individuals migrated to the estuarine environment during their first summer and returned to freshwater to overwinter before migrating back to sea. These results describe a diversity of viable habitat-use strategies by juvenile sockeye salmon that may buffer the population against poor conditions in any single rearing environment, reduce density-dependent mortality and have implications for the designation of critical habitat for conservation purposes. A network of accessible alternative habitats providing trade-offs in growth and survival may be important for long-term viability of populations.

  12. Timing of seasonal migration in mule deer: effects of climate, plant phenology, andlife-history characteristics

    OpenAIRE

    Monteith, Kevin L.; Bleich, Vernon C.; Stephenson, Thomas R.; Pierce, Becky M.; Conner, Mary M.; Klaver, Robert W.; Bowyer, R. Terry

    2011-01-01

    Phenological events of plants and animals are sensitive to climatic processes. Migration is a life-history event exhibited by most large herbivores living in seasonal environments, and is thought to occur in response to dynamics of forage and weather. Decisions regarding when to migrate, however, may be affected by differences in life-history characteristics of individuals. Long-term and intensive study of a population of mule deer (Odocoileus hemionus) in the Sierra Nevada, California, USA, ...

  13. Crisis, globality, and migration: Perspectives from the new times / Crisis, globalidad y migraciones: perspectivas de los nuevos tiempos

    Directory of Open Access Journals (Sweden)

    Vicente José Benito Gil

    2012-10-01

    Full Text Available The current global crisis and what this represents for the phenomenon of migration is the main object of analysis of this article. Through the principle topics that make up the title -crisis, globality, and migration- as well as the sub-themes -social integration, interculturalism, and the media- the author looks at the elements, causes, and circumstances that have shaped the current crisis, in terms of both economics and values, including the influence these, as the most important factors in human mobility of our time, have on the phenomenon of migration. All of this is considered from an analytical and reflective perspective, replete with varied proposals and criticisms. There is a common thread in the final outlook of the topics covered, which is the change that has occurred in the world with regard to human mobility, as well as in political and social behavior, all of which is a product of the new global order.

  14. GPU-accelerated Modeling and Element-free Reverse-time Migration with Gauss Points Partition

    Science.gov (United States)

    Zhen, Z.; Jia, X.

    2014-12-01

    Element-free method (EFM) has been applied to seismic modeling and migration. Compared with finite element method (FEM) and finite difference method (FDM), it is much cheaper and more flexible because only the information of the nodes and the boundary of the study area are required in computation. In the EFM, the number of Gauss points should be consistent with the number of model nodes; otherwise the accuracy of the intermediate coefficient matrices would be harmed. Thus when we increase the nodes of velocity model in order to obtain higher resolution, we find that the size of the computer's memory will be a bottleneck. The original EFM can deal with at most 81×81 nodes in the case of 2G memory, as tested by Jia and Hu (2006). In order to solve the problem of storage and computation efficiency, we propose a concept of Gauss points partition (GPP), and utilize the GPUs to improve the computation efficiency. Considering the characteristics of the Gaussian points, the GPP method doesn't influence the propagation of seismic wave in the velocity model. To overcome the time-consuming computation of the stiffness matrix (K) and the mass matrix (M), we also use the GPUs in our computation program. We employ the compressed sparse row (CSR) format to compress the intermediate sparse matrices and try to simplify the operations by solving the linear equations with the CULA Sparse's Conjugate Gradient (CG) solver instead of the linear sparse solver 'PARDISO'. It is observed that our strategy can significantly reduce the computational time of K and Mcompared with the algorithm based on CPU. The model tested is Marmousi model. The length of the model is 7425m and the depth is 2990m. We discretize the model with 595x298 nodes, 300x300 Gauss cells and 3x3 Gauss points in each cell. In contrast to the computational time of the conventional EFM, the GPUs-GPP approach can substantially improve the efficiency. The speedup ratio of time consumption of computing K, M is 120 and the

  15. Modeling approach to various time and spatial scale environmental issues in Fukushima. Related to radioactive cesium migration in aquatic systems

    International Nuclear Information System (INIS)

    Kurikami, Hiroshi; Kitamura, Akihiro; Yamada, Susumu; Machida, Masahiko

    2015-01-01

    Several numerical models have been prepared to deal with various time- and spatial-scale issues related to radioactive cesium migration in environment in Fukushima area. The SACT (Soil and Cesium Transport) model developed by the Japan Atomic Energy Agency (JAEA) predicts middle- to long-term evolution of radioactive cesium distribution due to soil erosion, subsequent sediment transport and deposition, and radioactive cesium migration based on the Universal Soil Loss Equation (USLE). The TODAM (Time-dependent One-dimensional Degradation and Migration) model, iRIC/Nays2D and the FLESCOT (Flow, Energy, Salinity, Sediment, Contaminant Transport) model are one-, two- and three-dimensional river/reservoir/coastal models, respectively. Based on conservation equations of sediment and radioactive cesium, they treat advection and diffusion of suspended sediment and cesium, deposition of sediment to bed, re-suspension from bed and adsorption/desorption of radioactive cesium. These models are suitable for small and short time scale issues such as high discharges of sediment and radioactive cesium from rivers due to heavy rainfall events. This paper describes fragments of the JAEA’s approaches of modeling to deal with the issues corresponding to radioactive cesium migration in environment with some case studies. (author)

  16. Juvenile Idiopathic Arthritis

    Directory of Open Access Journals (Sweden)

    Kenan Barut

    2017-04-01

    Full Text Available Juvenile idiopathic arthritis is the most common chronic rheumatic disease of unknown aetiology in childhood and predominantly presents with peripheral arthritis. The disease is divided into several subgroups, according to demographic characteristics, clinical features, treatment modalities and disease prognosis. Systemic juvenile idiopathic arthritis, which is one of the most frequent disease subtypes, is characterized by recurrent fever and rash. Oligoarticular juvenile idiopathic arthritis, common among young female patients, is usually accompanied by anti-nuclear antibodie positivity and anterior uveitis. Seropositive polyarticular juvenile idiopathic arthritis, an analogue of adult rheumatoid arthritis, is seen in less than 10% of paediatric patients. Seronegative polyarticular juvenile idiopathic arthritis, an entity more specific for childhood, appears with widespread large- and small-joint involvement. Enthesitis-related arthritis is a separate disease subtype, characterized by enthesitis and asymmetric lower-extremity arthritis. This disease subtype represents the childhood form of adult spondyloarthropathies, with human leukocyte antigen-B27 positivity and uveitis but commonly without axial skeleton involvement. Juvenile psoriatic arthritis is characterized by a psoriatic rash, accompanied by arthritis, nail pitting and dactylitis. Disease complications can vary from growth retardation and osteoporosis secondary to treatment and disease activity, to life-threatening macrophage activation syndrome with multi-organ insufficiency. With the advent of new therapeutics over the past 15 years, there has been a marked improvement in juvenile idiopathic arthritis treatment and long-term outcome, without any sequelae. The treatment of juvenile idiopathic arthritis patients involves teamwork, including an experienced paediatric rheumatologist, an ophthalmologist, an orthopaedist, a paediatric psychiatrist and a physiotherapist. The primary goals

  17. A model for simulating the active dispersal of juvenile sea turtles with a case study on western Pacific leatherback turtles

    Science.gov (United States)

    Lalire, Maxime

    2017-01-01

    Oceanic currents are known to broadly shape the dispersal of juvenile sea turtles during their pelagic stage. Accordingly, simple passive drift models are widely used to investigate the distribution at sea of various juvenile sea turtle populations. However, evidence is growing that juveniles do not drift purely passively but also display some swimming activity likely directed towards favorable habitats. We therefore present here a novel Sea Turtle Active Movement Model (STAMM) in which juvenile sea turtles actively disperse under the combined effects of oceanic currents and habitat-driven movements. This model applies to all sea turtle species but is calibrated here for leatherback turtles (Dermochelys coriacea). It is first tested in a simulation of the active dispersal of juveniles originating from Jamursba-Medi, a main nesting beach of the western Pacific leatherback population. Dispersal into the North Pacific Ocean is specifically investigated. Simulation results demonstrate that, while oceanic currents broadly shape the dispersal area, modeled habitat-driven movements strongly structure the spatial and temporal distribution of juveniles within this area. In particular, these movements lead juveniles to gather in the North Pacific Transition Zone (NPTZ) and to undertake seasonal north-south migrations. More surprisingly, juveniles in the NPTZ are simulated to swim mostly towards west which considerably slows down their progression towards the American west coast. This increases their residence time, and hence the risk of interactions with fisheries, in the central and eastern part of the North Pacific basin. Simulated habitat-driven movements also strongly reduce the risk of cold-induced mortality. This risk appears to be larger among the juveniles that rapidly circulate into the Kuroshio than among those that first drift into the North Equatorial Counter Current (NECC). This mechanism might induce marked interannual variability in juvenile survival as the

  18. A model for simulating the active dispersal of juvenile sea turtles with a case study on western Pacific leatherback turtles.

    Science.gov (United States)

    Gaspar, Philippe; Lalire, Maxime

    2017-01-01

    Oceanic currents are known to broadly shape the dispersal of juvenile sea turtles during their pelagic stage. Accordingly, simple passive drift models are widely used to investigate the distribution at sea of various juvenile sea turtle populations. However, evidence is growing that juveniles do not drift purely passively but also display some swimming activity likely directed towards favorable habitats. We therefore present here a novel Sea Turtle Active Movement Model (STAMM) in which juvenile sea turtles actively disperse under the combined effects of oceanic currents and habitat-driven movements. This model applies to all sea turtle species but is calibrated here for leatherback turtles (Dermochelys coriacea). It is first tested in a simulation of the active dispersal of juveniles originating from Jamursba-Medi, a main nesting beach of the western Pacific leatherback population. Dispersal into the North Pacific Ocean is specifically investigated. Simulation results demonstrate that, while oceanic currents broadly shape the dispersal area, modeled habitat-driven movements strongly structure the spatial and temporal distribution of juveniles within this area. In particular, these movements lead juveniles to gather in the North Pacific Transition Zone (NPTZ) and to undertake seasonal north-south migrations. More surprisingly, juveniles in the NPTZ are simulated to swim mostly towards west which considerably slows down their progression towards the American west coast. This increases their residence time, and hence the risk of interactions with fisheries, in the central and eastern part of the North Pacific basin. Simulated habitat-driven movements also strongly reduce the risk of cold-induced mortality. This risk appears to be larger among the juveniles that rapidly circulate into the Kuroshio than among those that first drift into the North Equatorial Counter Current (NECC). This mechanism might induce marked interannual variability in juvenile survival as the

  19. Long-term changes in migration timing of Song Thrush Turdus philomelos at the southern Baltic coast in response to temperatures on route and at breeding grounds.

    Science.gov (United States)

    Redlisiak, Michał; Remisiewicz, Magdalena; Nowakowski, Jarosław K

    2018-05-26

    Climate warming causes the advancement of spring arrival of many migrant birds breeding in Europe, but the effects on their autumn migration are less known. We aimed to determine any changes in the timing of Song Thrush captured during spring and autumn migrations at the Polish Baltic coast from 1975 to 2014, and if these were related to long-term changes of temperature at their breeding grounds and migration routes. The timing of spring migration at Hel ringing station in 1975-2014 did not show long-term advance, but they had responded to environmental conditions on the year-to-year basis. The warmer the temperatures were in April on their migration route, the earlier were the dates of the median and the end of spring migration at Hel. The beginning of autumn migration at the Mierzeja Wiślana ringing station advanced by 5 days between 1975 and 2014. The warmer the April on route, and the July at the Song Thrushes' breeding grounds, the earlier young birds began autumn migration across the Baltic coast. We suggest this was a combined effect of adults' migration and breeding early during warm springs and young birds getting ready faster for autumn migration during warm summers. The average time span of 90% of the autumn migration was extended by 5 days, probably because of early migration of young birds from first broods and late of those from second broods enabled by warm springs and summers. The response of Song Thrushes' migration timing to temperatures on route and at the breeding grounds indicated high plasticity in the species and suggested it might adapt well to climate changes.

  20. Juvenile prison in parallel legislation

    Directory of Open Access Journals (Sweden)

    Lutovac Mitar

    2016-01-01

    Full Text Available The need for punishment of juveniles occurred from the time when there was no clear line separating them from the adult criminal population. At the same time, the evolution of the juvenile punishment is not in itself involve substantial changes to their criminal status. On the contrary, the status of minors in society did not show serious differences regarding the status of young adults, as well as the adult elderly. On the other hand, on the ground of their punishment is recorded deviations that go in the direction of application of mild corporal punishment. Closing the minor was performed in a physically separate parts of the general penal institutions with the use of a lower degree of restrictions while serving juvenile prison. Due to the different treatment of minors during the evolution of their criminal status leads to their different treatment in comparative law. That is why we are witnessing the existence of numerous differences in the juvenile punishment in some countries in the world. On the European continent there is a wide range of different legal solutions when it comes to punishing juveniles. There are considerable differences in the procedure pronouncing juvenile prison and in particular penal treatment of juveniles in penitentiary institutions. For these reasons, the author has decided to show the basic statutory provisions in the part that relates to the issue of punishment of minors in the legislation of individual countries.

  1. Landsat time series analysis documents beaver migration into permafrost landscapes of arctic Alaska

    Science.gov (United States)

    Jones, B. M.; Tape, K. D.; Nitze, I.; Arp, C. D.; Grosse, G.; Zimmerman, C. E.

    2017-12-01

    Landscape-scale impacts of climate change in the Arctic include increases in growing season length, shrubby vegetation, winter river discharge, snowfall, summer and winter water temperatures, and decreases in river and lake ice thickness. Combined, these changes may have created conditions that are suitable for beaver colonization of low Arctic tundra regions. We developed a semi-automated workflow that analyzes Landsat imagery time series to determine the extent to which beavers may have colonized permafrost landscapes in arctic Alaska since 1999. We tested this approach on the Lower Noatak, Wulik, and Kivalina river watersheds in northwest Alaska and identified 83 locations representing potential beaver activity. Seventy locations indicated wetting trends and 13 indicated drying trends. Verification of each site using high-resolution satellite imagery showed that 80 % of the wetting locations represented beaver activity (damming and pond formation), 11 % were unrelated to beavers, and 9 % could not readily be distinguished as being beaver related or not. For the drying locations, 31 % represented beaver activity (pond drying due to dam abandonment), 62 % were unrelated to beavers, and 7 % were undetermined. Comparison of the beaver activity database with historic aerial photography from ca. 1950 and ca. 1980 indicates that beavers have recently colonized or recolonized riparian corridors in northwest Alaska. Remote sensing time series observations associated with the migration of beavers in permafrost landscapes in arctic Alaska include thermokarst lake expansion and drainage, thaw slump initiation, ice wedge degradation, thermokarst shore fen development, and possibly development of lake and river taliks. Additionally, beaver colonization in the Arctic may alter channel courses, thermal regimes, hyporheic flow, riparian vegetation, and winter ice regimes that could impact ecosystem structure and function in this region. In particular, the combination of beaver

  2. Climate change and timing of avian breeding and migration throughout Europe

    NARCIS (Netherlands)

    Both, Christiaan; te Marvelde, Luc

    2007-01-01

    Bird breeding and spring migration phenology have advanced in response to climate change, but the effects differ between sites. Here, we examine the geographical variation in laying-date trends in a short-distance migrant, the European starling Sturnus vulgaris, and a long-distance migrant, the pied

  3. What Is Juvenile Arthritis?

    Science.gov (United States)

    ... Initiative Breadcrumb Home Health Topics English Español Juvenile Arthritis Basics In-Depth Download Download EPUB Download PDF What is it? Points To Remember About Juvenile Arthritis Juvenile arthritis is the term used to describe ...

  4. Juvenile rheumatoid arthritis

    Science.gov (United States)

    ... joints. This form of JIA may turn into rheumatoid arthritis. It may involve 5 or more large and ... no known prevention for JIA. Alternative Names Juvenile rheumatoid arthritis (JRA); Juvenile chronic polyarthritis; Still disease; Juvenile spondyloarthritis ...

  5. Spatial dynamics of juvenile anchovy in the Bay of Biscay

    KAUST Repository

    Boyra, Guillermo; Peñ a, Marian; Cotano, Unai; Irigoien, Xabier; Rubio, Anna; Nogueira, Enrique

    2016-01-01

    In autumn 2009, the implementation of two successive acoustic surveys targeting juvenile anchovy (Engraulis encrasicolus) in the Bay of Biscay allowed us to monitor the changes in the spatial distribution and aggregation patterns of juveniles of this species during 45 days under fairly stable meteorological conditions. Juvenile anchovy changed its biological condition and behavior in a different manner in two distinct areas. In the Spanish sector, the juveniles migrated 20 nautical miles (n.mi.) towards the coast, but they remained on the shelf and near the surface during the whole surveyed period. As the advance towards the shelf break progressed, their area of distribution decreased, their density increased and the juveniles spread in fewer but heavier shoals. In the French sector, the juveniles also migrated from slope waters towards the coast at a similar velocity, but they crossed the shelf break into the continental shelf, where they increased their mean depth significantly until gradually adopting the typical nyctemeral migrations of adult anchovy. The mean length of the juveniles that adopted the nyctemeral migrations was significantly higher than that of the juveniles remaining at the surface, suggesting that body size is relevant to accomplish this change. Besides, the stronger temperature gradients between the shelf and oceanic waters in the Spanish sector, favored by a narrow shelf, may have acted as a barrier influencing the distinct observed spatial patterns in the two areas. © 2016 John Wiley & Sons Ltd

  6. Spatial dynamics of juvenile anchovy in the Bay of Biscay

    KAUST Repository

    Boyra, Guillermo

    2016-07-08

    In autumn 2009, the implementation of two successive acoustic surveys targeting juvenile anchovy (Engraulis encrasicolus) in the Bay of Biscay allowed us to monitor the changes in the spatial distribution and aggregation patterns of juveniles of this species during 45 days under fairly stable meteorological conditions. Juvenile anchovy changed its biological condition and behavior in a different manner in two distinct areas. In the Spanish sector, the juveniles migrated 20 nautical miles (n.mi.) towards the coast, but they remained on the shelf and near the surface during the whole surveyed period. As the advance towards the shelf break progressed, their area of distribution decreased, their density increased and the juveniles spread in fewer but heavier shoals. In the French sector, the juveniles also migrated from slope waters towards the coast at a similar velocity, but they crossed the shelf break into the continental shelf, where they increased their mean depth significantly until gradually adopting the typical nyctemeral migrations of adult anchovy. The mean length of the juveniles that adopted the nyctemeral migrations was significantly higher than that of the juveniles remaining at the surface, suggesting that body size is relevant to accomplish this change. Besides, the stronger temperature gradients between the shelf and oceanic waters in the Spanish sector, favored by a narrow shelf, may have acted as a barrier influencing the distinct observed spatial patterns in the two areas. © 2016 John Wiley & Sons Ltd

  7. Perbandingan Post Stack TIME Migration Metode Finite Difference dan Metode Kirchoff dengan Parameter Gap Dekonvolusi Data Seismik Darat 2d Line “Srda”

    OpenAIRE

    Dynza Anggary, Sheyza Rery; Danusaputro, Hernowo; Harmoko, Udi

    2015-01-01

    Analysis on Post Stack Time Migration (Post-STM) with finite difference method and Kirchoff method with determine gap parameter on deconvolution after stack had been applied to 2D land seismic at line “SRDA”. This research had purpose to applied seismic data processing to get subsurface imaging with high signal-to-noise ratio and analyze how the gap parameter corresponding on deconvolution after stack, and to determine which the appropriate method of migration between migration finite differe...

  8. The many shades of enhancement: timing of post-gadolinium images strongly influences the scoring of juvenile idiopathic arthritis wrist involvement on MRI

    Energy Technology Data Exchange (ETDEWEB)

    Rieter, Jasper F.M.M.; Nusman, Charlotte M.; Hemke, Robert; Maas, Mario [University of Amsterdam, Department of Radiology, Academic Medical Center, Amsterdam (Netherlands); Tanturri de Horatio, Laura [Ospedale Pediatrico Bambino Gesu, Department of Radiology, Rome (Italy); Ording Mueller, Lil-Sofie [Oslo University Hospital, Department of Radiology, Oslo (Norway); Avenarius, Derk F.M. [Faculty of Health Sciences at the University of Tromsoe, Tromsoe (Norway); Rossum, Marion A.J. van [University of Amsterdam, Department of Radiology, Academic Medical Center, Amsterdam (Netherlands); Emma Children' s Hospital, Amsterdam (Netherlands); Malattia, Clara [Ospedale Pediatrico Gaslini, Department of Paediatrics, Genoa (Italy); Rosendahl, Karen [Haukeland University Hospital, Radiology Department, Section of Pediatric Radiology, Bergen (Norway); University of Bergen, Department of Clinical Medicine, K1, Bergen (Norway)

    2016-10-15

    Potential long-term side effects of treatment for juvenile idiopathic arthritis are concerning. This has necessitated accurate tools, such as MRI, to monitor treatment response and allow for personalized therapy. To examine the extent to which timing of post-contrast MR images influences the scoring of inflammatory change in the wrist in children with juvenile idiopathic arthritis. We studied two sets of post-contrast 3-D gradient echo MRI series of the wrist in 34 children with juvenile idiopathic arthritis. These images were obtained immediately after administration of intravenous contrast material and again after approximately 10 min. The dataset was drawn from a prospective multicenter project conducted 2006-2010. We assessed five wrist locations for synovial enhancement, effusion and overall inflammation. Examinations were scored by one radiologist in two sessions - the first was based on the early post-contrast images, and the later session, for which the previous findings were masked, was based on the later post-contrast images. Fifty-two of the 170 locations (30.6%) received a higher synovial enhancement score based on the late post-contrast images as compared to the early images. Sixty of the 170 (35%) locations received a higher total inflammation score. The mean scores of synovial enhancement and total inflammation were significantly higher when based on the late post-contrast images as compared to the early post-contrast images. An MRI-based scoring system for the presence and degree of synovitis should be based on a standardized MR-protocol with a fixed interval between intravenous contrast injection and post-contrast images. (orig.)

  9. Fall migration routes, timing, and wintering sites of North American ospreys as determined by satellite telemetry

    Science.gov (United States)

    Martell, M.S.; Henny, Charles J.; Nye, P.; Solensky, Matthew J.

    2001-01-01

    Satellite telemetry was used to determine fall migratory movements of Ospreys (Pandion haliaetus) breeding in the United States. Study areas were established along the lower Columbia River between Oregon and Washington; in north-central Minnesota; on Shelter Island, New York; and in southern New Jersey. Seventy-four adults (25 males, 49 females) were tracked from 1995 through 1999. Migration routes differed among populations but not by sex. Western Ospreys migrated through California and to a lesser degree other western states and wintered in Mexico (88%), El Salvador (6%), and Honduras (6%) (25.9A?N to 13.0A?N and 108.3A?W to 87.3A?W). Minnesota Ospreys migrated along three routes: (1) through the Central U.S. and then along the east coast of Mexico, (2) along the Mississippi River Valley, then across the Gulf of Mexico, or (3) through the southeastern U.S., then across the Caribbean. East Coast birds migrated along the eastern seaboard of the U.S., through Florida, and across the Caribbean. Midwestern birds wintered from Mexico south to Bolivia (22.35A?N to 13.64A?S, and 91.75A?W to 61.76A?W), while East Coast birds wintered from Florida to as far south as Brazil (27.48A?N to 18.5A?S and 80.4A?W to 57.29A?W). Dates of departure from breeding areas differed significantly between sexes and geographic regions, with females leaving earlier than males. Western birds traveled a shorter distance than either midwestern or eastern Ospreys. Females traveled farther than males from the same population, which resulted in females typically wintering south of males.

  10. Transformations over Time or Sudden Change:Historical Perspectives on Mass Migrations and Human Lives

    Directory of Open Access Journals (Sweden)

    Dirk Hoerder

    2012-05-01

    Full Text Available Both migrations and attitudes towards them have deep historical roots. To pronounce the present migration and the economic crisis triggered by derivative bankers in the fall of 2008 as “new without historical precedent” overlooks the impact of patterns of the past on the present and prevents an understanding being reached of continuities and comparisons. It is not migrants who are “uprooted”, as some would have it, but historical memory is deliberately being uprooted. This essay starts by addressing the multiple problems of present-day debates about migration and historicising the perspectives. It critiques the anti-immigrant ascriptions, labels and ideologies. It goes on to present the data and discuss the geographies of migrant trajectories in the context of translocal, transregional, transnational and global connectivity. An integrative Transcultural Societal Studies approach will be proposed. The essay will then deal with migrant agency, that is the actions of migrants, criticising “victimization” approaches and argue that Otherness is a resource as well as a framework for exploitation. Remittances will serve as an example of the intersection between migrant agency and states’ needs. The conclusion will briefly place the present in the context of global inequalities, of the economic aspect and of anti-immigrantism, as well as the ideological national-essentialist aspect.

  11. Migration chemistry

    International Nuclear Information System (INIS)

    Carlsen, L.

    1992-05-01

    Migration chemistry, the influence of chemical -, biochemical - and physico-chemical reactions on the migration behaviour of pollutants in the environment, is an interplay between the actual natur of the pollutant and the characteristics of the environment, such as pH, redox conditions and organic matter content. The wide selection of possible pollutants in combination with varying geological media, as well as the operation of different chemical -, biochemical - and physico-chemical reactions compleactes the prediction of the influence of these processes on the mobility of pollutants. The report summarizes a wide range of potential pollutants in the terrestrial environment as well as a variety of chemical -, biochemical - and physico-chemical reactions, which can be expected to influence the migration behaviour, comprising diffusion, dispersion, convection, sorption/desorption, precipitation/dissolution, transformations/degradations, biochemical reactions and complex formation. The latter comprises the complexation of metal ions as well as non-polar organics to naturally occurring organic macromolecules. The influence of the single types of processes on the migration process is elucidated based on theoretical studies. The influence of chemical -, biochemical - and physico-chemical reactions on the migration behaviour is unambiguous, as the processes apparently control the transport of pollutants in the terrestrial environment. As the simple, conventional K D concept breaks down, it is suggested that the migration process should be described in terms of the alternative concepts chemical dispersion, average-elution-time and effective retention. (AB) (134 refs.)

  12. No association between vitamin D levels around time of birth and later risk of developing oligo- and polyarticular juvenile idiopathic arthritis

    DEFF Research Database (Denmark)

    Thorsen, S. U.; Pipper, C. B.; Alberdi-Saugstrup, M.

    2017-01-01

    -hydroxyvitamin D [25(OH)D] around time of birth would be associated with increased risk of oligo- or polyarticular JIA. Method: We conducted a case–cohort study of validated cases diagnosed with oligo- and polyarticular JIA (1993–2012) and controls matched on date of birth. Cases and controls were born......Objectives: Basic and epidemiological studies on rheumatic autoimmune diseases have suggested an association between vitamin D levels around time of birth and disease risk. The literature on vitamin D and juvenile idiopathic arthritis (JIA) is scarce. We hypothesized that low levels of 25...... regression and a two-way analysis of variance (ANOVA) was used to test for season and birth year 25(OH)D variations. A total of 300 matched pairs were included in the statistical analyses. Results: No significant association was found between levels of 25(OH)D and JIA risk in the adjusted model [OR (per 25...

  13. Monitoring in real time the effect of TLX overexpression on proliferation and migration of C6 cells.

    Science.gov (United States)

    Li, G L; Fang, S H; Xu, B

    2017-01-01

    Orphan nuclear receptor TLX has been shown to play an essential role in regulating the self-renewal and proliferation of neural stem cells (NSCs). However, TLX overexpression in NSCs induces long-term NSC expansion and further leads to glioma initiation in mouse when combined with p53 mutations. Whether overexpression of TLX plays a role in glioma stem cell (GSC) proliferation and migration still remains largely unknown. In this study, we infected C6 cells, a special glioma cell line which is mainly composed of cancer stem cells(CSCs), with lentiviruses expressing GFP(LV-GFP) or GFP-T2A-TLX(LV-TLX) and then monitored cell proliferation and migration using the real-time analyzer system (RTCA, xCELLigence, Roche). We found that the cell index (CI) observed for the TLX overexpressing C6 cells showed a lower value than that of the LV-GFP transduced cells. And the MTT results correlated highly with the RTCA proliferation assessments. Furthermore, the expression of p21 was decreased while other downstream genes PTEN and p53 were not significantly changed in TLX overexpressing C6 cells . These findings strongly indicate that TLX overexpression has the ability to decrease the proliferating and migratory properties of C6 cells by targeting p21. Further, our results suggest that TLX overexpression may also have a similar inhibitory effect on GSC proliferation and migration.

  14. Post-breeding migration of Dutch-breeding black-tailed godwits: timing, routes, use of stopovers, and nonbreeding destinations

    Science.gov (United States)

    Hooijmeijer, Jos C. E. W.; Senner, Nathan R.; Tibbitts, T. Lee; Gill, Robert E.; Douglas, David C.; Bruinzeel, Leo W.; Wymenga, Eddy; Piersma, Theunis

    2014-01-01

    Conservation of long-distance migratory shorebirds is complex because these species use habitats spread across continents and hemispheres, making identification of critical habitats and potential bottlenecks in the annual cycle especially difficult. The population of Black-tailed Godwits that breeds in Western Europe, Limosa limosa limosa, has declined precipitously over the past few decades. Despite significant efforts to identify the root causes of this decline, much remains unclear. To better understand the migratory timing, use of stopover and nonbreeding sites, and the potential impact of breeding success on these parameters, we attached 15 Argos satellite transmitters and 10 geolocation tracking devices to adult godwits nearing completion of incubation at breeding sites in southwest Friesland, The Netherlands during the spring of 2009. We successfully tracked 16 adult godwits for their entire southward migration and two others for part of it. Three migration patterns and four regions of use were apparent. Most godwits left their breeding sites and proceeded south directly to stopover sites in the Mediterranean — e.g. Spain, Portugal, and Morocco — before flying on to non-breeding sites in West Africa. Other individuals spent the entire nonbreeding season in the Mediterranean. A third pattern included a few individuals that flew nonstop from their Dutch breeding sites to nonbreeding sites in West Africa. Tracking data from this study will be immediately useful for conservation efforts focused on preserving the dispersed network of sites used by godwits during their southward migration.

  15. Are polygonal faults the keystone for better understanding the timing of fluid migration in sedimentary basins?

    Science.gov (United States)

    Gay, Aurélien

    2017-06-01

    The initial sediment lithification starts with complex interactions involving minerals, surface water, decomposing organic matter and living organisms. This is the eogenesis domain (0 to 2 km below the seafloor) in which the sediments are subject to physical, chemical and mechanical transformations defining the early fabric of rocks. This interval is intensively prospected for its energy/mining resources (hydrocarbons, metal deposits, geothermal energy). In most basins worldwide it is composed of very fine-grained sediments and it is supposed to play the role of a seal for fluids migration. However, it is affected by polygonal faulting due to a volume loss during burial by contraction of clay sediments with a high smectite content. This process is of high interest for fractured reservoirs and/or cover integrity but it is not well constrained giving an uncertainty as this interval can either promote the migration of deeper fluids and the mineralized fluids intensifies diagenesis in the fracture planes, rendering this interval all the more impermeable. The next challenge will be to define where, when and how does this polygonal fault interval occur and this can only be done by understanding the behavior of clay grains and fluids during early burial.

  16. Are polygonal faults the keystone for better understanding the timing of fluid migration in sedimentary basins?

    Directory of Open Access Journals (Sweden)

    Gay Aurélien

    2017-01-01

    Full Text Available The initial sediment lithification starts with complex interactions involving minerals, surface water, decomposing organic matter and living organisms. This is the eogenesis domain (0 to 2 km below the seafloor in which the sediments are subject to physical, chemical and mechanical transformations defining the early fabric of rocks. This interval is intensively prospected for its energy/mining resources (hydrocarbons, metal deposits, geothermal energy. In most basins worldwide it is composed of very fine-grained sediments and it is supposed to play the role of a seal for fluids migration. However, it is affected by polygonal faulting due to a volume loss during burial by contraction of clay sediments with a high smectite content. This process is of high interest for fractured reservoirs and/or cover integrity but it is not well constrained giving an uncertainty as this interval can either promote the migration of deeper fluids and the mineralized fluids intensifies diagenesis in the fracture planes, rendering this interval all the more impermeable. The next challenge will be to define where, when and how does this polygonal fault interval occur and this can only be done by understanding the behavior of clay grains and fluids during early burial.

  17. Comparative Analysis of Dynamic Cell Viability, Migration and Invasion Assessments by Novel Real-Time Technology and Classic Endpoint Assays

    Science.gov (United States)

    Limame, Ridha; Wouters, An; Pauwels, Bea; Fransen, Erik; Peeters, Marc; Lardon, Filip; De Wever, Olivier; Pauwels, Patrick

    2012-01-01

    Background Cell viability and motility comprise ubiquitous mechanisms involved in a variety of (patho)biological processes including cancer. We report a technical comparative analysis of the novel impedance-based xCELLigence Real-Time Cell Analysis detection platform, with conventional label-based endpoint methods, hereby indicating performance characteristics and correlating dynamic observations of cell proliferation, cytotoxicity, migration and invasion on cancer cells in highly standardized experimental conditions. Methodology/Principal Findings Dynamic high-resolution assessments of proliferation, cytotoxicity and migration were performed using xCELLigence technology on the MDA-MB-231 (breast cancer) and A549 (lung cancer) cell lines. Proliferation kinetics were compared with the Sulforhodamine B (SRB) assay in a series of four cell concentrations, yielding fair to good correlations (Spearman's Rho 0.688 to 0.964). Cytotoxic action by paclitaxel (0–100 nM) correlated well with SRB (Rho>0.95) with similar IC50 values. Reference cell migration experiments were performed using Transwell plates and correlated by pixel area calculation of crystal violet-stained membranes (Rho 0.90) and optical density (OD) measurement of extracted dye (Rho>0.95). Invasion was observed on MDA-MB-231 cells alone using Matrigel-coated Transwells as standard reference method and correlated by OD reading for two Matrigel densities (Rho>0.95). Variance component analysis revealed increased variances associated with impedance-based detection of migration and invasion, potentially caused by the sensitive nature of this method. Conclusions/Significance The xCELLigence RTCA technology provides an accurate platform for non-invasive detection of cell viability and motility. The strong correlations with conventional methods imply a similar observation of cell behavior and interchangeability with other systems, illustrated by the highly correlating kinetic invasion profiles on different

  18. Long-Term Trends in Marriage Timing and the Impact of Migration, the Netherlands (1650-1899

    Directory of Open Access Journals (Sweden)

    Charlotte Störmer

    2017-12-01

    Full Text Available The features of historical marriage patterns have been linked to debates in social and economic history about economic growth and female agency. However, there is a lack of empirical evidence on the demographics of marriage prior to the nineteenth century. Here, we study trends in sex-specific ages at first marriage, regional variation and the impact of migration on marital timing in the Netherlands in the period 1650-1900. We make use of two new large historical datasets, namely an aggregation of Dutch genealogies and the transcribed marriage banns of Amsterdam. This allows us to understand the features and developments of marriage ages from a long-term perspective in what is known as one of the core-areas of the so-called European Marriage Pattern. Our results show high marriage ages for both sexes from the beginning of our study period, increasing until the mid-19th century. A closer look at regional variation reveals clear differences between the provinces and between urban and rural settings with those in the western part of the country and in urban centers marrying earlier. Migrating individuals married on average later than non-migrating individuals both compared to men and women in the receiving community, as to the ‘stayers’ in the location of origin. As later marriage implies a reduction of the window of fertility, especially for women, our results suggest that migration and increasing regional mobility might have been an important driver of the demographic shift toward higher marriage ages and lower fertility in Europe between the 17th and 19th centuries.

  19. Comparative analysis of dynamic cell viability, migration and invasion assessments by novel real-time technology and classic endpoint assays.

    Directory of Open Access Journals (Sweden)

    Ridha Limame

    Full Text Available BACKGROUND: Cell viability and motility comprise ubiquitous mechanisms involved in a variety of (pathobiological processes including cancer. We report a technical comparative analysis of the novel impedance-based xCELLigence Real-Time Cell Analysis detection platform, with conventional label-based endpoint methods, hereby indicating performance characteristics and correlating dynamic observations of cell proliferation, cytotoxicity, migration and invasion on cancer cells in highly standardized experimental conditions. METHODOLOGY/PRINCIPAL FINDINGS: Dynamic high-resolution assessments of proliferation, cytotoxicity and migration were performed using xCELLigence technology on the MDA-MB-231 (breast cancer and A549 (lung cancer cell lines. Proliferation kinetics were compared with the Sulforhodamine B (SRB assay in a series of four cell concentrations, yielding fair to good correlations (Spearman's Rho 0.688 to 0.964. Cytotoxic action by paclitaxel (0-100 nM correlated well with SRB (Rho>0.95 with similar IC(50 values. Reference cell migration experiments were performed using Transwell plates and correlated by pixel area calculation of crystal violet-stained membranes (Rho 0.90 and optical density (OD measurement of extracted dye (Rho>0.95. Invasion was observed on MDA-MB-231 cells alone using Matrigel-coated Transwells as standard reference method and correlated by OD reading for two Matrigel densities (Rho>0.95. Variance component analysis revealed increased variances associated with impedance-based detection of migration and invasion, potentially caused by the sensitive nature of this method. CONCLUSIONS/SIGNIFICANCE: The xCELLigence RTCA technology provides an accurate platform for non-invasive detection of cell viability and motility. The strong correlations with conventional methods imply a similar observation of cell behavior and interchangeability with other systems, illustrated by the highly correlating kinetic invasion profiles on

  20. Collisional activation by MALDI tandem time-of-flight mass spectrometry induces intramolecular migration of amide hydrogens in protonated peptides

    DEFF Research Database (Denmark)

    Jørgensen, Thomas J D; Bache, Nicolai; Roepstorff, Peter

    2005-01-01

    of doubly protonated peptides that the original regioselective deuterium pattern of these peptides is completely erased (Jørgensen, T. J. D., Gårdsvoll, H., Ploug, M., and Roepstorff, P. (2005) Intramolecular migration of amide hydrogens in protonated peptides upon collisional activation. J. Am. Chem. Soc...... randomization among all exchangeable sites (i.e. all N- and O-linked hydrogens) also occurs upon high energy collisional activation of singly protonated peptides. This intense proton/deuteron traffic precludes the use of MALDI tandem time-of-flight mass spectrometry to obtain reliable information...

  1. Single and combined effects of microplastics and mercury on juveniles of the European seabass (Dicentrarchus labrax): Changes in behavioural responses and reduction of swimming velocity and resistance time.

    Science.gov (United States)

    Barboza, Luís Gabriel Antão; Vieira, Luís Russo; Guilhermino, Lúcia

    2018-05-01

    Microplastics and mercury are environmental pollutants of great concern. The main goal of the present study was to investigate the effects of these pollutants, both individually and in binary mixtures, on the swimming performance of juvenile European seabass, Dicentrarchus labrax. Microplastics alone, mercury alone and all the mixtures caused significant reduction of the swimming velocity and resistance time of fish. Moreover, changes in behavioural responses including lethargic and erratic swimming behaviour were observed. These results highlight that fish behavioural responses can be used as sensitive endpoint to establish the effects of contamination by microplastics and also emphasizes the need to assess the combined effects of microplastics and other environmental contaminants, with special attention to the effects on behavioural responses in fish and other aquatic species. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Expression of S1P metabolizing enzymes and receptors correlate with survival time and regulate cell migration in glioblastoma multiforme.

    Science.gov (United States)

    Bien-Möller, Sandra; Lange, Sandra; Holm, Tobias; Böhm, Andreas; Paland, Heiko; Küpper, Johannes; Herzog, Susann; Weitmann, Kerstin; Havemann, Christoph; Vogelgesang, Silke; Marx, Sascha; Hoffmann, Wolfgang; Schroeder, Henry W S; Rauch, Bernhard H

    2016-03-15

    A signaling molecule which is involved in proliferation and migration of malignant cells is the lipid mediator sphingosine-1-phosphate (S1P). There are hints for a potential role of S1P signaling in malignant brain tumors such as glioblastoma multiforme (GBM) which is characterized by a poor prognosis. Therefore, a comprehensive expression analysis of S1P receptors (S1P1-S1P5) and S1P metabolizing enzymes in human GBM (n = 117) compared to healthy brain (n = 10) was performed to evaluate their role for patient´s survival. Furthermore, influence of S1P receptor inhibition on proliferation and migration were studied in LN18 GBM cells. Compared to control brain, mRNA levels of S1P1, S1P2, S1P3 and S1P generating sphingosine kinase-1 were elevated in GBM. Kaplan-Meier analyses demonstrated an association between S1P1 and S1P2 with patient´s survival times. In vitro, an inhibitory effect of the SphK inhibitor SKI-II on viability of LN18 cells was shown. S1P itself had no effect on viability but stimulated LN18 migration which was blocked by inhibition of S1P1 and S1P2. The participation of S1P1 and S1P2 in LN18 migration was further supported by siRNA-mediated silencing of these receptors. Immunoblots and inhibition experiments suggest an involvement of the PI3-kinase/AKT1 pathway in the chemotactic effect of S1P in LN18 cells.In summary, our data argue for a role of S1P signaling in proliferation and migration of GBM cells. Individual components of the S1P pathway represent prognostic factors for patients with GBM. Perspectively, a selective modulation of S1P receptor subtypes could represent a therapeutic approach for GBM patients and requires further evaluation.

  3. The influence of time in captivity, food intake and acute trauma on blood analytes of juvenile Steller sea lions, Eumetopias jubatus

    Science.gov (United States)

    Skinner, John P.; Tuomi, Pam A.; Mellish, Jo-Ann E.

    2015-01-01

    The Steller sea lion, Eumetopias jubatus, has experienced regionally divergent population trends over recent decades. One potential mechanism for this disparity is that local factors cause reduced health and, therefore, reduced survival of individuals. The use of blood parameters to assess sea lion health may help to identify whether malnutrition, disease and stress are important drivers of current trends, but such assessments require species-specific knowledge of how parameters respond to various health challenges. We used principal components analysis to identify which key blood parameters (principal analytes) best described changes in health for temporarily captive juvenile Steller sea lions in known conditions. Generalized additive mixed models were used to estimate the changes in principal analytes with food intake, time in captivity and acute trauma associated with hot-iron branding and transmitter implant surgery. Of the 17 blood parameters examined, physiological changes for juvenile sea lions were best described using the following six principal analytes: red blood cell counts, white blood cell counts, globulin, platelets, glucose and total bilirubin. The white blood cell counts and total bilirubin declined over time in captivity, whereas globulin increased. Elevated red blood cell counts, white blood cell counts and total bilirubin and reduced globulin values were associated with lower food intake. After branding, white blood cell counts were elevated for the first 30 days, while globulin and platelets were elevated for the first 15 days only. After implant surgery, red blood cell counts and globulin remained elevated for 30 days, while white blood cell counts remained elevated during the first 15 days only. Glucose was unassociated with the factors we studied. These results were used to provide expected ranges for principal analytes at different levels of food intake and in response to the physical challenges of branding and implant surgery

  4. An empirical test of combined theory of juvenile delinquency

    Directory of Open Access Journals (Sweden)

    Moshkani Z

    1998-06-01

    Full Text Available Juvenile delinquency is a social problem disturbing families, social institutions and government agencies. Delinquent juveniles lose valuable opportunities concerning their education and occupation. This paper, has undertaken a field research on the causes of delinquency among juveniles arrested in the greater Tehran. The theoretical framework was established by combining the social control theory of Hirschi and the differential association theory of Sutherland and Cressy. The resultant theory made it possible to take account of both internal and external forces leading to delinquency. From 140 boys and 15 girls of under 18 arrested in 1992 in the greater Tehran, ninety boys and all girls were randomly chosen for interview. Four variables showing delinqueint acts and 81 independent variables concerning their personal characteristics, living environment and migrations, family support, beliefs and practices, association with criminals and pass-time activities and hobbies were measured. A factor analysis were applied to reduce the size of data matrix. Thus, one factor was found as a response variable representing the intensity of youth's delinquency. The independent variables were reduced to 28 factors. A multiple regression analysis showed that only 3 factors were enough to explain the intensity of delinquency. Those factors are the "attachment", "beliefs and attitudes" and "association with criminals"

  5. Two Trees: Migrating Fault Trees to Decision Trees for Real Time Fault Detection on International Space Station

    Science.gov (United States)

    Lee, Charles; Alena, Richard L.; Robinson, Peter

    2004-01-01

    We started from ISS fault trees example to migrate to decision trees, presented a method to convert fault trees to decision trees. The method shows that the visualizations of root cause of fault are easier and the tree manipulating becomes more programmatic via available decision tree programs. The visualization of decision trees for the diagnostic shows a format of straight forward and easy understands. For ISS real time fault diagnostic, the status of the systems could be shown by mining the signals through the trees and see where it stops at. The other advantage to use decision trees is that the trees can learn the fault patterns and predict the future fault from the historic data. The learning is not only on the static data sets but also can be online, through accumulating the real time data sets, the decision trees can gain and store faults patterns in the trees and recognize them when they come.

  6. Parenting and juvenile delinquency

    NARCIS (Netherlands)

    Hoeve, M.

    2008-01-01

    Juvenile delinquency is a noteworthy problem. This thesis addressed the association between parenting and juvenile delinquency by analyzing the concepts of parenting adopted in family research in relation to criminological concepts and measures of delinquent behavior. Four studies were conducted.

  7. Evaluation of Juvenile Salmonid Outmigration and Survival in the Lower Umatilla River Basin, Annual Report 2003-2006.

    Energy Technology Data Exchange (ETDEWEB)

    White, Tara

    2007-02-01

    This report summarizes activities conducted by the Oregon Department of Fish and Wildlife's Juvenile Outmigration and Survival M&E project in the Umatilla River subbasin between 2004-2006. Information is used to make informed decisions on hatchery effectiveness, natural production success, passage improvement and flow enhancement strategies. Data collected includes annual estimates of smolt abundance, migration timing, and survival, life history characteristics and productivity status and trends for spring and fall Chinook salmon, coho salmon and summer steelhead. Productivity data provided is the key subbasin scale measure of the effectiveness of salmon and steelhead restoration actions in the Umatilla River. Information is also used for regional planning and recovery efforts of Mid-Columbia River (MCR) ESA-listed summer steelhead. Monitoring is conducted via smolt trapping and PIT-tag interrogation at Three Mile Falls Dam. The Umatilla Juvenile Outmigration and Survival Project was established in 1994 to evaluate the success of management actions and fisheries restoration efforts in the Umatilla River Basin. Project objectives for the 2004-2006 period were to: (1) operate the PIT tag detection system at Three Mile Falls Dam (TMFD), (2) enhance provisional PIT-tag interrogation equipment at the east bank adult fish ladder, (3) monitor the migration timing, abundance and survival of naturally-produced juvenile salmonids and trends in natural production, (4) determine migration parameters and survival of hatchery-produced fish representing various rearing, acclimation and release strategies, (5) evaluate the relative survival between transported and non-transported fish, (6) monitor juvenile life history characteristics and evaluate trends over time, (7) investigate the effects of river, canal, fishway operations and environmental conditions on smolt migration and survival, (8) document the temporal distribution and diversity of resident fish species, and (9

  8. Multi-component pre-stack time-imaging and migration-based velocity analysis in transversely isotropic media; Imagerie sismique multicomposante et analyse de vitesse de migration en milieu transverse isotrope

    Energy Technology Data Exchange (ETDEWEB)

    Gerea, C.V.

    2001-06-01

    Complementary to the recording of compressional (P-) waves, the observation of P-S converted waves has recently been receiving specific attention. This is mainly due to their tremendous potential as a tool for fracture and lithology characterization, imaging sediments in gas saturated rocks, and imaging shallow sediments with higher resolution than conventional P-P data. In a conventional marine seismic survey, we cannot record P-to-S converted-wave energy since the fluids cannot support shear-wave strain. Thus, to capture the converted-wave energy, we need to record it at the water-bottom casing an ocean-bottom cable (OBC). The S-waves recorded at the seabed are mainly converted from P to S (i.e., PS-waves or C-waves) at the subsurface reflectors. The most accurate way to image seismic data is pre-stack depth migration. In this thesis, I develop a numerically efficient 2.5-D true-amplitude elastic Kirchhoff pre-stack migration algorithm designed to handle OBC data gathered along a single line. All the kinematic and dynamic elastic Green's functions required in the computation of true-amplitude weight term of Kirchhoff summation, are based on the non-hyperbolic explicit approximations of P- and SV-wave travel-times in layered transversely isotropic (VTI) media. Hence, this elastic imaging algorithm is very well-suited for migration-based velocity analysis techniques, for which fast, robust and iterative pre-stack migration is desired. In this thesis, I approach also the topic of anisotropic velocity model building for elastic pre-stack time-imaging. and propose an original methodology for joint PP-PS migration-based velocity analysis (MVA) in layered VTI anisotropic media. Tests on elastic synthetic and real OBC seismic data ascertain the validity of the pre-stack migration algorithm and velocity analysis methodology. (author)

  9. Juvenile Court Statistics - 1972.

    Science.gov (United States)

    Office of Youth Development (DHEW), Washington, DC.

    This report is a statistical study of juvenile court cases in 1972. The data demonstrates how the court is frequently utilized in dealing with juvenile delinquency by the police as well as by other community agencies and parents. Excluded from this report are the ordinary traffic cases handled by juvenile court. The data indicate that: (1) in…

  10. Juvenile Court Statistics, 1974.

    Science.gov (United States)

    Corbett, Jacqueline; Vereb, Thomas S.

    This report presents information on juvenile court processing of youth in the U.S. during 1974. It is based on data gathered under the National Juvenile Court Statistical Reporting System. Findings can be summarized as follows: (1) 1,252,700 juvenile delinquency cases, excluding traffic offenses, were handled by courts in the U.S. in 1974; (2) the…

  11. Evolution of Juvenile Ankylosing Spondylitis

    Directory of Open Access Journals (Sweden)

    Ye.V. Prohorov

    2013-02-01

    Full Text Available Evolution of juvenile ankylosing spondylitis tend to follow a more frequent involvement in the pathological process of elbow and ankle joints, development of enthesiopathies, changes of intraarticular meniscal horns, forming of Baker’s cysts, cartilage flaps and systemic osteoporosis, and total value of all these signs 13 times exceeds thereof in patients with with the debut of disease in adulthood, but for juvenile ankylosing spondylitis vertebral lesion is less common. Age dimorphism of the use of certain groups of drugs and physiotherapy facilities is observed.

  12. 3D seismic modeling and reverse‐time migration with the parallel Fourier method using non‐blocking collective communications

    KAUST Repository

    Chu, Chunlei

    2009-01-01

    The major performance bottleneck of the parallel Fourier method on distributed memory systems is the network communication cost. In this study, we investigate the potential of using non‐blocking all‐to‐all communications to solve this problem by overlapping computation and communication. We present the runtime comparison of a 3D seismic modeling problem with the Fourier method using non‐blocking and blocking calls, respectively, on a Linux cluster. The data demonstrate that a performance improvement of up to 40% can be achieved by simply changing blocking all‐to‐all communication calls to non‐blocking ones to introduce the overlapping capability. A 3D reverse‐time migration result is also presented as an extension to the modeling work based on non‐blocking collective communications.

  13. Rapid expansion method (REM) for time‐stepping in reverse time migration (RTM)

    KAUST Repository

    Pestana, Reynam C.; Stoffa, Paul L.

    2009-01-01

    an analytical approximation for the Bessel function where we assume that the time step is sufficiently small. From this derivation we find that if we consider only the first two Chebyshev polynomials terms in the rapid expansion method we can obtain the second

  14. On the Mutual Dynamics of Interregional Gross Migration Flows in Space and Time

    DEFF Research Database (Denmark)

    Mitze, Timo

    2016-01-01

    This paper applies spatial dynamic panel data models to analyse the labor market dimension of interregional population flows among German federal states in the period 1993–2009. Making use of recent improvements in the estimation of space-time dynamic panel data models and the computation of mean...

  15. A topological approach to migration and visualization of time-varying volume data

    International Nuclear Information System (INIS)

    Fujishiro, Issei; Otsuka, Rieko; Hamaoka, Aya; Takeshima, Yuriko; Takahashi, Shigeo

    2004-01-01

    Rapid advance in high performance computing and measurement technologies has recently made it possible to produce a stupendous amount of time-varying volume datasets in various disciplines. However, there exist a few known visual exploration tools which allow us to investigate the core of their complex behavior effectively. In this article, our previous approach to topological volume skeletonization is extended to capture the topological skeleton of a 4D volumetric field in terms of critical timing. A cyclic information drilldown scheme, termed T-map, is presented, where a wide choice of information visualization techniques are deployed so that the users are allowed to repeatedly squeeze partial spatiotemporal domains of interest until the size gets fitted into an available computing storage space, prior to topologically-accentuated visualization of the pinpointed volumetric domains. A case study with datasets from atomic collision research is performed to illustrate the feasibility of the present method. (author)

  16. 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.

  17. Population, migration and urbanization.

    Science.gov (United States)

    1982-06-01

    Despite recent estimates that natural increase is becoming a more important component of urban growth than rural urban transfer (excess of inmigrants over outmigrants), the share of migration in the total population growth has been consistently increasing in both developed and developing countries. From a demographic perspective, the migration process involves 3 elements: an area of origin which the mover leaves and where he or she is considered an outmigrant; the destination or place of inmigration; and the period over which migration is measured. The 2 basic types of migration are internal and international. Internal migration consists of rural to urban migration, urban to urban migration, rural to rural migration, and urban to rural migration. Among these 4 types of migration various patterns or processes are followed. Migration may be direct when the migrant moves directly from the village to the city and stays there permanently. It can be circular migration, meaning that the migrant moves to the city when it is not planting season and returns to the village when he is needed on the farm. In stage migration the migrant makes a series of moves, each to a city closer to the largest or fastest growing city. Temporary migration may be 1 time or cyclical. The most dominant pattern of internal migration is rural urban. The contribution of migration to urbanization is evident. For example, the rapid urbanization and increase in urban growth from 1960-70 in the Republic of Korea can be attributed to net migration. In Asia the largest component of the population movement consists of individuals and groups moving from 1 rural location to another. Recently, because urban centers could no longer absorb the growing number of migrants from other places, there has been increased interest in the urban to rural population redistribution. This reverse migration also has come about due to slower rates of employment growth in the urban centers and improved economic opportunities

  18. Time Reversal Migration for Passive Sources Using a Maximum Variance Imaging Condition

    KAUST Repository

    Wang, H.; Alkhalifah, Tariq Ali

    2017-01-01

    The conventional time-reversal imaging approach for micro-seismic or passive source location is based on focusing the back-propagated wavefields from each recorded trace in a source image. It suffers from strong background noise and limited acquisition aperture, which may create unexpected artifacts and cause error in the source location. To overcome such a problem, we propose a new imaging condition for microseismic imaging, which is based on comparing the amplitude variance in certain windows, and use it to suppress the artifacts as well as find the right location for passive sources. Instead of simply searching for the maximum energy point in the back-propagated wavefield, we calculate the amplitude variances over a window moving in both space and time axis to create a highly resolved passive event image. The variance operation has negligible cost compared with the forward/backward modeling operations, which reveals that the maximum variance imaging condition is efficient and effective. We test our approach numerically on a simple three-layer model and on a piece of the Marmousi model as well, both of which have shown reasonably good results.

  19. An ‘infiltration’ of time? Hindu Chauvinism and Bangladeshi migration in/to Kolkata, India

    Directory of Open Access Journals (Sweden)

    Gautam Ghosh

    2015-06-01

    Full Text Available In the context of the growth of Hindu chauvinism (Hindutva in India, this article explores the ways Bengali middle-class caste-Hindus have become increasingly anti-Bangladeshi and, in particular, increasingly hostile to immigrants into India from Bangladesh. The aim is two-fold. First, to show that a main reason for the increasingly anti-Bangladeshi sentiment is these Bengali Hindus’ particular experience of or, more precisely, their particular interpretation of, their own location in Indian history. This group, at times referred to as the bhadralok, had once seen itself, not without reason, as India’s national elite and has sought to re-establish that status. Second, it is suggested that the Bangladeshi immigrants represent an “infiltration” or “interruption” of time as much as territory, providing the temporal backdrop for anti-Bangladeshi resentment. In this case the temporality at issue is the postcolonial imperative of progress. The paper suggests that attention to issues of temporality can shed light on key aspects of nationalism — postcolonial nationalism and perhaps more broadly liberal nationalism — in relation to, among other matters, the legitimation of leadership.

  20. Time Reversal Migration for Passive Sources Using a Maximum Variance Imaging Condition

    KAUST Repository

    Wang, H.

    2017-05-26

    The conventional time-reversal imaging approach for micro-seismic or passive source location is based on focusing the back-propagated wavefields from each recorded trace in a source image. It suffers from strong background noise and limited acquisition aperture, which may create unexpected artifacts and cause error in the source location. To overcome such a problem, we propose a new imaging condition for microseismic imaging, which is based on comparing the amplitude variance in certain windows, and use it to suppress the artifacts as well as find the right location for passive sources. Instead of simply searching for the maximum energy point in the back-propagated wavefield, we calculate the amplitude variances over a window moving in both space and time axis to create a highly resolved passive event image. The variance operation has negligible cost compared with the forward/backward modeling operations, which reveals that the maximum variance imaging condition is efficient and effective. We test our approach numerically on a simple three-layer model and on a piece of the Marmousi model as well, both of which have shown reasonably good results.

  1. Effect of environmental conditions on the migration of DI (2-Ethylhexyl) Phthalate from PET bottles into yogurt drinks: Influence of time, temperature and food simulant

    International Nuclear Information System (INIS)

    Farhoodi, M.; Emam-Djomeh, Z.; Ehsani, Mohammad Reza; Oromiehie, A.

    2008-01-01

    Polyethylene terephthalate (PET) is one of the materials that are widely used for packaging of beverages and edible oils. In this study, the migration of di (2-ethylhexyl) phthalate (DEHP) from PET bottles into the Iranian yogurt drink was investigated. According to European Commission regulations, acetic acid (3% w/v) was chosen as stimulant. The acetic acid samples were stored at 4C, 25C and 45Cfor four months and analyzed periodically by gas chromatography. Differential Scanning Calorimetry (DSC) was used to investigate if contact with the food stimulant could affect the PET material. It was concluded that the storage temperature had a large effect on the migration of DEHP. Also, increasing storage time resulted in higher concentrations of migrating DEHP. The concentrations of migrating substance did not exceed its specific migration limit (Economic European Community (EEC) regulations). Determination of glass transition (Tg) and crystallinity percent of PET bottles using DSC method showed that the variations in the amount of migration at different storage condition did not induce any change in the PET material in contact with 3% acetic acid. (author)

  2. Effect of environmental conditions on the migration of di(2-ethylhexyl)phthalate from pet bottles into yogurt drinks: influence of time, temperature, and food simulant

    International Nuclear Information System (INIS)

    Farhoodi, Mehdi; Djomeh, Zahra Emam; Ehsani, Mohammad Reza; Oromiehie, Abdolrasul

    2008-01-01

    Polyethylene terephthalate (PET) is one of the materials that are widely used for packaging of beverages and edible oils. In this study, the migration of di(2-ethylhexyl)phthalate (DEHP) from PET bottles into the Iranian yogurt drink was investigated. According to European Commission regulations, acetic acid (3% w/v) was chosen as simulant. The acetic acid samples were stored at 4 degree C, 25 degree C, and 45 degree C for four months and analyzed periodically by gas chromatography. Differential Scanning Calorimetry (DSC) was used to investigate if contact with the food simulant could affect the PET material. It was concluded that the storage temperature had a large effect on the migration of DEHP. Also, increasing storage time resulted in higher concentrations of migrating DEHP. The concentrations of migrating substance did not exceed its specific migration limit (Economic European Community (EEC) regulations). Determination of glass transition (Tg) and crystallinity percent of PET bottles using DSC method showed that the variations in the amount of migration at different storage condition did not induce any change in the PET material in contact with 3% acetic acid. (author)

  3. Migration Timing and Parenting Practices: Contributions to Social Development in Preschoolers with Foreign-Born and Native-Born Mothers

    Science.gov (United States)

    Glick, Jennifer E.; Hanish, Laura D.; Yabiku, Scott T.; Bradley, Robert H.

    2012-01-01

    Little is known about how key aspects of parental migration or childrearing history affect social development across children from immigrant families. Relying on data on approximately 6,400 children from the Early Childhood Longitudinal Study-Birth Cohort, analyses assessed the role of mother's age at migration on children's social development in…

  4. Network Dependency in Migration Flows – A Space-time Analysis for Germany since Re-unification

    DEFF Research Database (Denmark)

    Mitze, Timo

    The contribution of this paper is to analyse the role of network interdependencies in a dynamic panel data model for German internal migration fl ows since re-unification. So far, a capacious account of spatial patterns in German migration data is still missing in the empirical literature. In the...

  5. Testing three common stocking methods: Differences in smolt size, migration rate and timing of two strains of stocked Atlantic salmon ( Salmo salar )

    DEFF Research Database (Denmark)

    Birnie-Gauvin, Kim; Larsen, Martin Hage; Thomassen, Søren T.

    2018-01-01

    The influence of three common stocking practices for two strains (Ätran and Burrishoole) of hatchery-reared Atlantic salmon, Salmo salar, on smolt size, migration probability and migration timing were investigated in situ. Using a common garden experiment, fish from these populations were release...... to inherited factors, and emphasize the importance of considering age of fish and time spent in the hatchery when stocking populations in the wild to maximize smolt output......The influence of three common stocking practices for two strains (Ätran and Burrishoole) of hatchery-reared Atlantic salmon, Salmo salar, on smolt size, migration probability and migration timing were investigated in situ. Using a common garden experiment, fish from these populations were released...... as fry, half-year olds and oneyear olds. Our results indicate that fish released at the fry and half-year stage produce smaller smolts, and migrate later in the year than their counterparts released at one-year of age, for both the Ätran and the Burrishoole populations. While fry had the lowest...

  6. Timing magma migration through the Icelandic Crust: from the Moho to the surface

    Science.gov (United States)

    Mutch, E. J. F.; Maclennan, J.; Edmonds, M.

    2017-12-01

    The rate of magma transfer throughout the crust, particularly the amount of time it takes for melt to travel from the upper mantle to the surface, is largely unknown. Only one previous study has investigated the timescales of transport of crystals that were in equilibrium with mantle melts [1]. Despite estimating timescales on the order of months to years, the depths from which these crystals were entrained is poorly constrained. Borgarhraun is an exceptionally well-characterised picrite lava flow in the Theistareykir Volcanic System of Northern Iceland. The crystal-cargo of this lava includes macrocrysts of olivine (Fo86-90), plagioclase (An84-90), clinopyroxene and spinel with much rarer wehrlitic nodules. Crystallisation has been estimated to have taken place in deep sub-Moho magma chambers ( 24 km). Melt inclusions in primitive olivine macrocrysts (Fo88-90) are the result of mixing a suite of geochemically distinct mantle melts that were CO2 undersaturated [2-3]. Zoning in the macrocrysts holds a record of concurrent crystallisation and mixing of these variable mantle melts, as well as ascent through the crust prior to eruption [4]. We have conducted a multi-phase, multi-element approach by applying finite-element diffusion models to wehrlite olivines and plagioclase macrocrysts to constrain the timescales of crystal residence and magma ascent prior to eruption. Model results suggest that at 1250 °C the timescale of final ascent was on the order of 20-50 days, whilst longer-term crystal residence times can exceed 700 years. This analysis shows that magma can ascend from the base of the crust to the surface in under a couple of months, suggesting picrites such as Borgarhraun are the result of high speed conduits to sub-Moho magma chambers. These rapid ascent timescales have important implications for the physical modelling of primitive magmas as well as for understanding the architecture of magma-plumbing systems in the temporal domain. References [1] Ruprecht

  7. Modeling caprock fracture, CO2 migration and time dependent fault healing: A numerical study.

    Science.gov (United States)

    MacFarlane, J.; Mukerji, T.; Vanorio, T.

    2017-12-01

    The Campi Flegrei caldera, located near Naples, Italy, is one of the highest risk volcanoes on Earth due to its recent unrest and urban setting. A unique history of surface uplift within the caldera is characterized by long duration uplift and subsidence cycles which are periodically interrupted by rapid, short period uplift events. Several models have been proposed to explain this history; in this study we will present a hydro-mechanical model that takes into account the caprock that seismic studies show to exist at 1-2 km depth. Specifically, we develop a finite element model of the caldera and use a modified version of fault-valve theory to represent fracture within the caprock. The model accounts for fault healing using a simplified, time-dependent fault sealing model. Multiple fracture events are incorporated by using previous solutions to test prescribed conditions and determine changes in rock properties, such as porosity and permeability. Although fault-valve theory has been used to model single fractures and recharge, this model is unique in its ability to model multiple fracture events. By incorporating multiple fracture events we can assess changes in both long and short-term reservoir behavior at Campi Flegrei. By varying the model inputs, we model the poro-elastic response to CO2 injection at depth and the resulting surface deformation. The goal is to enable geophysicists to better interpret surface observations and predict outcomes from observed changes in reservoir conditions.

  8. Migratory Behavior and Survival of Juvenile Salmonids in the Lower Columbia River and Estuary in 2009

    Energy Technology Data Exchange (ETDEWEB)

    McMichael, Geoffrey A.; Harnish, Ryan A.; Bellgraph, Brian J.; Carter, Jessica A.; Ham, Kenneth D.; Titzler, P. Scott; Hughes, Michael S.

    2010-08-01

    The study reported herein was funded as part of the Anadromous Fish Evaluation Program, which is managed by the U.S. Army Corps of Engineers (USACE). The Anadromous Fish Evaluation Program study code is EST P 02 01: A Study of Salmonid Survival and Behavior through the Columbia River Estuary Using Acoustic Tags. The study was conducted by the Pacific Northwest National Laboratory (PNNL) and National Oceanic and Atmospheric Administration (NOAA) Fisheries for the USACE Portland District. Estimated survival of acoustic-tagged juvenile Chinook salmon and steelhead through the lower Columbia River and estuary in 2009 was lowest in the final 50 km of the estuary. Probability of survival was relatively high (>0.90) for yearling and subyearling Chinook salmon from the Bonneville Dam forebay (rkm 236) to Three-tree Point (rkm 49.6). Survival of juvenile Chinook salmon declined sharply through the lower 50 km of the estuary. Acoustic-tagged steelhead smolts did not survive as well as juvenile Chinook salmon between Bonneville Dam and the mouth of the Columbia River. Steelhead survival began to decline farther upstream (at rkm 86) relative to that of the Chinook salmon stocks. Subyearling Chinook salmon survival decreased markedly as the season progressed. It remains to be determined whether later migrating subyearling Chinook salmon are suffering increasing mortality as the season progresses or whether some portion of the apparent loss is due to fish extending their freshwater residence. This study provided the first glimpse into what promises to be a very informative way to learn more about how juvenile salmonid passage experiences through the FCRPS may influence their subsequent survival after passing Bonneville Dam. New information regarding the influence of migration pathway through the lower 50 km of the Columbia River estuary on probability of survival of juvenile salmonids, combined with increased understanding regarding the foraging distances and time periods of

  9. Aurelia labiata jellyfish in Roscoe Bay on the West Coast of Canada: Seasonal changes in adult bell diameter and mingling of juvenile and adult populations

    Science.gov (United States)

    Albert, David J.; Walsh, Michael L.

    2014-01-01

    The bell diameter of adult Aurelia labiata in Roscoe Bay increased from spring (April) to early summer (May/June) and decreased over the rest of the year (2009/2010). The increase in bell diameter in the spring would have been supported by the increase in zooplankton that occurs in the northeast Pacific at this time. Over the summer, bell diameter may have decreased because the food available/medusa would have been decreased by the arrival of a large number of juveniles and may have decreased further over the fall and winter when zooplankton levels are known to be low. Adults and juveniles were intermingled during 2010, 2011, and 2012. Correlations between the number of adults and number of juveniles obtained in individual net lifts across the entire bay and in different parts of the bay were all positive and most were statistically significant. In 2012, salinity in the entire water column of the west side of the bay dropped below 20 ppt in July and most medusae migrated to higher salinity in the east side of the bay, a distance of about 0.5 km. The mingling of adults and juveniles supports other evidence that adult Aurelia sp. medusae do not prey upon juveniles. The ability to withstand months with insufficient food and to inhibit preying on juveniles would contribute greatly to the survival of Aurelia sp. jellyfish.

  10. Juvenile Arthritis

    Science.gov (United States)

    ... OII) Timed Up & Go (TUG) Western Ontario & McMaster Universities Osteoarthritis Index (WOMAC) Young Investigators Resources for Doctoral Students/Post-Doctoral Fellows Evidence-Based Practice for Academic Researchers Responsible Data Management in Research Career Planning Treatments Patient ...

  11. Dermatomyositis (Juvenile)

    Science.gov (United States)

    ... OII) Timed Up & Go (TUG) Western Ontario & McMaster Universities Osteoarthritis Index (WOMAC) Young Investigators Resources for Doctoral Students/Post-Doctoral Fellows Evidence-Based Practice for Academic Researchers Responsible Data Management in Research Career Planning Treatments Patient ...

  12. Temporal patterns of migration and spawning of river herring in coastal Massachusetts

    Science.gov (United States)

    Rosset, Julianne; Roy, Allison; Gahagan, Benjamin I.; Whiteley, Andrew R.; Armstrong, Michael P.; Sheppard, John J.; Jordaan, Adrian

    2017-01-01

    Migrations of springtime Alewife Alosa pseudoharengus and Blueback Herring A. aestivalis, collectively referred to as river herring, are monitored in many rivers along the Atlantic coast to estimate population sizes. While these estimates give an indication of annual differences in the number of returning adults, links to the subsequent timing and duration of spawning and freshwater juvenile productivity remain equivocal. In this study, we captured juvenile river herring at night in 20 coastal Massachusetts lakes using a purse seine and extracted otoliths to derive daily fish ages and back-calculate spawn dates. Estimates of spawning dates were compared with fishway counts of migrating adults to assess differences in migration timing and the timing and duration of spawning. We observed a distinct delay between the beginning of the adult migration run and the start of spawning, ranging from 7 to 28 d across the 20 lakes. Spawning continued 13–48 d after adults stopped migrating into freshwater, further demonstrating a pronounced delay in spawning following migration. Across the study sites the duration of spawning (43–76 d) was longer but not related to the duration of migration (29–66 d). The extended spawning period is consistent with recent studies suggesting that Alewives are indeterminate spawners. The long duration in freshwater provides the opportunity for top-down (i.e., predation on zooplankton) and bottom-up (i.e., food for avian, fish, and other predators) effects, with implications for freshwater food webs and nutrient cycling. General patterns of spawn timing and duration can be incorporated into population models and used to estimate temporal changes in productivity associated with variable timing and density of spawning river herring in lakes.

  13. Unraveling the Timing of Fluid Migration and Trap Formation in the Brooks Range Foothills: A Key to Discovering Hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Catherine L. Hanks

    2008-12-31

    Naturally occurring fractures can play a key role in the evolution and producibility of a hydrocarbon accumulation. Understanding the evolution of fractures in the Brooks Range/Colville basin system of northern Alaska is critical to developing a better working model of the hydrocarbon potential of the region. This study addressed this problem by collecting detailed and regional data on fracture distribution and character, structural geometry, temperature, the timing of deformation along the Brooks Range rangefront and adjacent parts of the Colville basin, and the in situ stress distribution within the Colville basin. This new and existing data then were used to develop a model of how fractures evolved in northern Alaska, both spatially and temporally. The results of the study indicate that fractures formed episodically throughout the evolution of northern Alaska, due to a variety of mechanisms. Four distinct fracture sets were observed. The earliest fractures formed in deep parts of the Colville basin and in the underlying Ellesmerian sequence rocks as these rocks experienced compression associated with the growing Brooks Range fold-and-thrust belt. The orientation of these deep basin fractures was controlled by the maximum in situ horizontal stress in the basin at the time of their formation, which was perpendicular to the active Brooks Range thrust front. This orientation stayed consistently NS-striking for most of the early history of the Brooks Range and Colville basin, but changed to NW-striking with the development of the northeastern Brooks Range during the early Tertiary. Subsequent incorporation of these rocks into the fold-and-thrust belt resulted in overprinting of these deep basin fractures by fractures caused by thrusting and related folding. The youngest fractures developed as rocks were uplifted and exposed. While this general order of fracturing remains consistent across the Brooks Range and adjacent Colville basin, the absolute age at any one

  14. Motorized Migrations: the Future or Mere Fantasy?

    Science.gov (United States)

    Ellis, D.H.; Sladen, William J. L.; Lishman, W.A.; Clegg, K.R.; Duff, J.W.; Gee, G.F.; Lewis, J.C.

    2003-01-01

    In 15 experiments from 1993-2002, we led cranes, geese, or swans on their first southward migration with either ultralight aircraft or vehicles on the ground. These experiments reveal that large birds can be readily trained to follow and most will return north (and south) in subsequent migrations unassisted. These techniques can now be used to teach birds new (or forgotten) migration paths. Although we are constantly improving our training techniques, we now have an operational program that can be broadly applied to those species where juveniles learn migration routes from their parents.

  15. AFSC/ABL: Juvenile chum salmon allozyme stock identification, Bering Sea 2002

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Genetic stock identification techniques were used to identify the origin and provide stock-specific migration and distribution patterns of juvenile chum...

  16. A semelparous fish continues upstream migration when exposed to alarm cue, but adjusts movement speed and timing

    Science.gov (United States)

    Luhring, Thomas M; Meckley, Trevor D.; Johnson, Nicholas S.; Siefkes, Michael J.; Hume, John B.; Wagner, C. Michael

    2016-01-01

    Animals make trade-offs between predation risk and pursuit of opportunities such as foraging and reproduction. Trade-offs between antipredator behaviours and foraging are well suited to manipulation in laboratory and field settings and have generated a vast compendium of knowledge. However, much less is known about how animals manage trade-offs between predation risk and pursuit of reproductive opportunities in the absence of the confounding effects of foraging. In the present study, we investigated how the nonfeeding migratory life stage of sea lamprey, Petromyzon marinus, responds to odour from dead conspecifics (a cue that induces avoidance behaviours in laboratory and field studies). We released groups of PIT-tagged sea lamprey 65 m from the shore of Lake Michigan or 287 m upstream in Carp Lake River and used antennas to detect their movements in the river. As the breeding season progressed, sea lamprey initiated upstream movement earlier and were more likely to enter the river. Sea lamprey that began the night in Lake Michigan entered Carp Lake River at higher rates and accelerated upstream when exposed to high concentrations of alarm cue, consistent with animals attempting to minimize time spent in risky areas. Sea lampreys that began the night in the river delayed upstream movement when exposed to alarm cue, consistent with animals sheltering and gathering information about a source of risk. We attribute this context-specific reaction to alarm cue to differences in perceived vulnerability to predation in sheltered positions in the river versus exposed positions in the lake. Once in the river, the vast majority of sea lamprey moved upstream independent of alarm cue or Julian date. Although life-history-induced time and energy budgets place rigid constraints on the direction of migration, sea lamprey attend to predation risk by modifying movement timing and speed.

  17. 3D Seismic Imaging through Reverse-Time Migration on Homogeneous and Heterogeneous Multi-Core Processors

    Directory of Open Access Journals (Sweden)

    Mauricio Araya-Polo

    2009-01-01

    Full Text Available Reverse-Time Migration (RTM is a state-of-the-art technique in seismic acoustic imaging, because of the quality and integrity of the images it provides. Oil and gas companies trust RTM with crucial decisions on multi-million-dollar drilling investments. But RTM requires vastly more computational power than its predecessor techniques, and this has somewhat hindered its practical success. On the other hand, despite multi-core architectures promise to deliver unprecedented computational power, little attention has been devoted to mapping efficiently RTM to multi-cores. In this paper, we present a mapping of the RTM computational kernel to the IBM Cell/B.E. processor that reaches close-to-optimal performance. The kernel proves to be memory-bound and it achieves a 98% utilization of the peak memory bandwidth. Our Cell/B.E. implementation outperforms a traditional processor (PowerPC 970MP in terms of performance (with an 15.0× speedup and energy-efficiency (with a 10.0× increase in the GFlops/W delivered. Also, it is the fastest RTM implementation available to the best of our knowledge. These results increase the practical usability of RTM. Also, the RTM-Cell/B.E. combination proves to be a strong competitor in the seismic arena.

  18. Determining when a fracture occurred: Does the method matter? Analysis of the similarity of three different methods for estimating time since fracture of juvenile long bones.

    Science.gov (United States)

    Drury, Anne; Cunningham, Craig

    2018-01-01

    Radiographic fracture date estimation is a critical component of skeletal trauma analysis in the living. Several timetables have been proposed for how the appearance of radiographic features can be interpreted to provide a likely time frame for fracture occurrence. This study compares three such timetables for pediatric fractures, by Islam et al. (2000), Malone et al. (2011), and Prosser et al. (2012), in order to determine whether the fracture date ranges produced by using these methods are in agreement with one another. Fracture date ranges were estimated for 112 long bone fractures in 96 children aged 1-17 years, using the three different timetables. The extent of similarity of the intervals was tested by statistically comparing the overlap between the ranges. Results showed that none of the methods were in perfect agreement with one another. Differences seen included the size of the estimated date range for when a fracture occurred, and the specific dates given for both the upper and lower ends of the fracture date range. There was greater similarity between the ranges produced by Malone et al. (2011) and both the other two studies than there was between Islam et al. (2000) and Prosser et al. (2012). The greatest similarity existed between Malone et al. (2011) and Islam et al. (2000). The extent of differences between methods can vary widely, depending on the fracture analysed. Using one timetable gives an average earliest possible fracture date of less than 2 days before another, but the range was extreme, with one method estimating minimum time since fracture as 25 days before another method for a given fracture. In most cases, one method gave maximum time since fracture as a week less than the other two methods, but range was extreme and some estimates were nearly two months different. The variability in fracture date estimates given by these timetables indicates that caution should be exercised when estimating the timing of a juvenile fracture if relying

  19. Survival estimates for the passage of juvenile salmonids through Snake River dams and reservoirs, 1996. Annual report

    International Nuclear Information System (INIS)

    Smith, S.G.; Muir, W.D.; Hockersmith, E.E.; Achord, S.; Eppard, M.B.; Ruehle, T.E.; Williams, J.G.

    1998-02-01

    In 1996, the National Marine Fisheries Service and the University of Washington completed the fourth year of a multi-year study to estimate survival of juvenile salmonids (Oncorhynchus spp.) passing through dams and reservoirs on the Snake River. Actively migrating smolts were collected near the head of Lower Granite Reservoir and at Lower Granite Dam, tagged with passive integrated transponder (PIT) tags, and released to continue their downstream migration. Individual smolts were subsequently detected at PIT-tag detection facilities at Lower Granite, Little Goose, Lower Monumental, McNary, John Day and Bonneville Dams. Survival estimates were calculated using the Single-Release (SR) and Paired-Release (PR) Models. Timing of releases of tagged hatchery steelhead (O. mykiss) from the head of Lower Granite Reservoir and yearling chinook salmon (O. tshawytscha) from Lower Granite Dam in 1996 spanned the major portion of their juvenile migrations. Specific research objectives in 1996 were to (1) estimate reach and project survival in the Snake River using the Single-Release and Paired-Release Models throughout the yearling chinook salmon and steelhead migrations, (2) evaluate the performance of the survival-estimation models under prevailing operational and environmental conditions in the Snake River, and (3) synthesize results from the 4 years of the study to investigate relationships between survival probabilities, travel times, and environmental factors such as flow levels and water temperature

  20. Survival Estimates for the Passage of Juvenile Salmonids through Snake River Dams and Reservoirs, 1996 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Steven G.

    1998-02-01

    In 1996, the National Marine Fisheries Service and the University of Washington completed the fourth year of a multi-year study to estimate survival of juvenile salmonids (Oncorhynchus spp.) passing through dams and reservoirs on the Snake River. Actively migrating smolts were collected near the head of Lower Granite Reservoir and at Lower Granite Dam, tagged with passive integrated transponder (PIT) tags, and released to continue their downstream migration. Individual smolts were subsequently detected at PIT-tag detection facilities at Lower Granite, Little Goose, Lower Monumental, McNary, John Day and Bonneville Dams. Survival estimates were calculated using the Single-Release (SR) and Paired-Release (PR) Models. Timing of releases of tagged hatchery steelhead (O. mykiss) from the head of Lower Granite Reservoir and yearling chinook salmon (O. tshawytscha) from Lower Granite Dam in 1996 spanned the major portion of their juvenile migrations. Specific research objectives in 1996 were to (1) estimate reach and project survival in the Snake River using the Single-Release and Paired-Release Models throughout the yearling chinook salmon and steelhead migrations, (2) evaluate the performance of the survival-estimation models under prevailing operational and environmental conditions in the Snake River, and (3) synthesize results from the 4 years of the study to investigate relationships between survival probabilities, travel times, and environmental factors such as flow levels and water temperature.

  1. Migratory Behavior and Survival of Juvenile Salmonids in the Lower Columbia River, Estuary, and Plume in 2010

    Energy Technology Data Exchange (ETDEWEB)

    McMichael, Geoffrey A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Harnish, Ryan A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Skalski, John R. [Univ. of Washington, Seattle, WA (United States); Deters, Katherine A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ham, Kenneth D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Townsend, Richard L. [Univ. of Washington, Seattle, WA (United States); Titzler, P. Scott [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hughes, Michael S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kim, Jin A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Trott, Donna M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2011-09-01

    of the river at higher rates, with estimated survival probabilities of 84% and 86%, respectively. The influence of route of passage at the lower three dams in the FCRPS on juvenile salmonid survival appeared to be relatively direct and immediate. Significant differences in estimated survival probabilities of juvenile salmonid smolts among groups with different dam passage experiences were often detected between the dams and rkm 153. In contrast, the influence of route of passage on survival to the mouth of the Columbia River was not apparent among the groups of tagged juvenile salmonids with different FCRPS passage experiences after they had already survived to a point about 80 km downstream of Bonneville Dam. Yearling Chinook salmon and steelhead smolts that migrated through the lower estuary in off-channel habitats took two to three times longer to travel through these lower reaches and their estimated survival probabilities were not significantly different from that of their cohorts which migrated in or near the navigation channel. A large proportion of the tagged juvenile salmonids migrating in or near the navigation channel in the lower estuary crossed from the south side of the estuary near Astoria, Oregon and passed through relatively shallow expansive sand flats (Taylor Sands) to the North Channel along the Washington shore of the estuary. This migratory behavior may contribute to the avian predation losses observed on for fish (2 to 12% of fish in this study).

  2. Inhibition of cell migration by focal adhesion kinase: Time-dependent difference in integrin-induced signaling between endothelial and hepatoblastoma cells.

    Science.gov (United States)

    Yu, Hongchi; Gao, Min; Ma, Yunlong; Wang, Lijuan; Shen, Yang; Liu, Xiaoheng

    2018-05-01

    angiogenesis plays an important role in the development and progression of tumors, and it involves a series of signaling pathways contributing to the migration of endothelial cells for vascularization and to the invasion of cancer cells for secondary tumor formation. Among these pathways, the focal adhesion kinase (FAK) signaling cascade has been implicated in a variety of human cancers in connection with cell adhesion and migration events leading to tumor angiogenesis, metastasis and invasion. Therefore, the inhibition of FAK in endothelial and/or cancer cells is a potential target for anti‑angiogenic therapy. In the present study, a small‑molecule FAK inhibitor, 1,2,4,5-benzenetetramine tetrahydrochloride (Y15), was used to study the effects of FAK inhibition on the adhesion and migration behaviors of vascular endothelial cells (VECs) and human hepatoblastoma cells. Furthermore, the time-dependent differences in proteins associated with the integrin-mediated FAK/Rho GTPases signaling pathway within 2 h were examined. The results indicated that the inhibition of FAK significantly decreased the migration ability of VECs and human hepatoblastoma cells in a dose-dependent manner. Inhibition of FAK promoted cell detachment by decreasing the expression of focal adhesion components, and blocked cell motility by reducing the level of Rho GTPases. However, the expression of crucial proteins involved in integrin-induced signaling in two cell lines exhibited a time-dependent difference with increased duration of FAK inhibitor treatment, suggesting different mechanisms of FAK-mediated cell migration behavior. These results suggest that the mechanism underlying FAK-mediated adhesion and migration behavior differs among various cells, which is expected to provide evidence for future FAK therapy targeted against tumor angiogenesis.

  3. Effective modeling and reverse-time migration for novel pure acoustic wave in arbitrary orthorhombic anisotropic media

    Science.gov (United States)

    Xu, Shigang; Liu, Yang

    2018-03-01

    The conventional pseudo-acoustic wave equations (PWEs) in arbitrary orthorhombic anisotropic (OA) media usually have coupled P- and SV-wave modes. These coupled equations may introduce strong SV-wave artifacts and numerical instabilities in P-wave simulation results and reverse-time migration (RTM) profiles. However, pure acoustic wave equations (PAWEs) completely decouple the P-wave component from the full elastic wavefield and naturally solve all the aforementioned problems. In this article, we present a novel PAWE in arbitrary OA media and compare it with the conventional coupled PWEs. Through decomposing the solution of the corresponding eigenvalue equation for the original PWE into an ellipsoidal differential operator (EDO) and an ellipsoidal scalar operator (ESO), the new PAWE in time-space domain is constructed by applying the combination of these two solvable operators and can effectively describe P-wave features in arbitrary OA media. Furthermore, we adopt the optimal finite-difference method (FDM) to solve the newly derived PAWE. In addition, the three-dimensional (3D) hybrid absorbing boundary condition (HABC) with some reasonable modifications is developed for reducing artificial edge reflections in anisotropic media. To improve computational efficiency in 3D case, we adopt graphic processing unit (GPU) with Compute Unified Device Architecture (CUDA) instead of traditional central processing unit (CPU) architecture. Several numerical experiments for arbitrary OA models confirm that the proposed schemes can produce pure, stable and accurate P-wave modeling results and RTM images with higher computational efficiency. Moreover, the 3D numerical simulations can provide us with a comprehensive and real description of wave propagation.

  4. Time trends in cardiovascular disease mortality in Russia and Germany from 1980 to 2007 - are there migration effects?

    Directory of Open Access Journals (Sweden)

    Deckert Andreas

    2010-08-01

    Full Text Available Abstract Background Cardiovascular disease (CVD is the leading cause of death in the industrialized world. Large variations in CVD mortality between countries and also between population subgroups within countries have been observed. Previous studies showed significantly lower risks in German repatriates and Jews emigrating from Russia than in the general Russian population. We examined to what degree the migration of large subgroups influenced national CVD mortality rates. Methods We used WHO data to map the CVD mortality distribution in Europe in 2005. Supplemented by data of the Statistisches Bundesamt, the mortality trends in three major CVD groups between 1980 and 2007 in Russia and Germany are displayed, as well as demographic information. The effects of migration on demography were estimated and percentage changes in CVD mortality trends were calculated under the assumption that migration had not occurred. Results Cardiovascular disease mortality patterns within Europe showed a strong west-east gradient with ratios up to sixfold. In Germany, the CVD mortality levels were low and steadily decreasing, whereas in Russia they fluctuated at high levels with substantial differences between the sexes and strong correlations with political changes and health campaigns. The trends in both Russia and Germany were affected by the migration that occurred in both countries over recent decades. However, our restricted focus in only adjusting for the migration of German repatriates and Jews had moderate effects on the national CVD mortality statistics in Germany (+1.0% and Russia (-0.6%. Conclusions The effects on CVD mortality rates due to migration in Germany and Russia were smaller than those due to secular economical changes. However, migration should still be considered as a factor influencing national mortality trends.

  5. Time trends in cardiovascular disease mortality in Russia and Germany from 1980 to 2007 - are there migration effects?

    Science.gov (United States)

    Deckert, Andreas; Winkler, Volker; Paltiel, Ari; Razum, Oliver; Becher, Heiko

    2010-08-17

    Cardiovascular disease (CVD) is the leading cause of death in the industrialized world. Large variations in CVD mortality between countries and also between population subgroups within countries have been observed. Previous studies showed significantly lower risks in German repatriates and Jews emigrating from Russia than in the general Russian population. We examined to what degree the migration of large subgroups influenced national CVD mortality rates. We used WHO data to map the CVD mortality distribution in Europe in 2005. Supplemented by data of the Statistisches Bundesamt, the mortality trends in three major CVD groups between 1980 and 2007 in Russia and Germany are displayed, as well as demographic information. The effects of migration on demography were estimated and percentage changes in CVD mortality trends were calculated under the assumption that migration had not occurred. Cardiovascular disease mortality patterns within Europe showed a strong west-east gradient with ratios up to sixfold. In Germany, the CVD mortality levels were low and steadily decreasing, whereas in Russia they fluctuated at high levels with substantial differences between the sexes and strong correlations with political changes and health campaigns. The trends in both Russia and Germany were affected by the migration that occurred in both countries over recent decades. However, our restricted focus in only adjusting for the migration of German repatriates and Jews had moderate effects on the national CVD mortality statistics in Germany (+1.0%) and Russia (-0.6%). The effects on CVD mortality rates due to migration in Germany and Russia were smaller than those due to secular economical changes. However, migration should still be considered as a factor influencing national mortality trends.

  6. Migration depth and residence time of juvenile salmonids in the forebays of hydropower dams prior to passage through turbines or juvenile bypass systems: implications for turbine-passage survival

    OpenAIRE

    Li, Xinya; Deng, Zhiqun D.; Brown, Richard S.; Fu, Tao; Martinez, Jayson J.; McMichael, Geoffrey A.; Skalski, John R.; Townsend, Richard L.; Trumbo, Bradly A.; Ahmann, Martin L.; Renholds, Jon F.

    2015-01-01

    Little is known about the three-dimensional depth distributions in rivers of individually marked fish that are in close proximity to hydropower facilities. Knowledge of the depth distributions of fish approaching dams can be used to understand how vulnerable fish are to injuries such as barotrauma as they pass through dams. To predict the possibility of barotrauma injury caused by pressure changes during turbine passage, it is necessary to understand fish behaviour relative to acclimation dep...

  7. Juvenile Confinement in Context

    Science.gov (United States)

    Mendel, Richard A.

    2012-01-01

    For more than a century, the predominant strategy for the treatment and punishment of serious and sometimes not-so-serious juvenile offenders in the United States has been placement into large juvenile corrections institutions, alternatively known as training schools, reformatories, or youth corrections centers. America's heavy reliance on…

  8. Juvenile giant fibroadenoma

    Directory of Open Access Journals (Sweden)

    Vipul Yagnik

    2011-07-01

    Full Text Available Fibroadenomas are benign solid tumor associated with aberration of normal lobular development. Juvenile giant fibroadenoma is usually single and >5 cm in size /or >500 gms in weight. Important differential diagnoses are: phyllodes tumor and juvenile gigantomastia. Simple excision is the treatment of choice.

  9. Juvenile mammary papillomatosis; Papilomatosis juvenil mamaria

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, M.; Jimenez, A. V. [Hospital Reina Sofia. Cordoba (Spain)

    2001-07-01

    Juvenile mammary papillomatosis is a benign proliferative disease of young patients, generally under 30 years of age. The most frequent clinical presentation is the existence of an elastic and mobile lymph node of the breast. Anatomopathologically, it is characterized because it presents ductal epithelial hyperplasia, sometimes with marked atypia, and there are numerous cysts having different sizes among the findings. It has been associated with an increase in the incidence of breast cancer, both in the patient herself as well as her family. We review the literature on the subject and present the mammographic and ultrasonographic findings of a 22 year old woman diagnosed of juvenile mammary papillomatosis. (Author) 12 refs.

  10. Apparent dissociation of photoperiodic time measurement between vernal migration and breeding under dim green light conditions in Gambel's white-crowned sparrow Zonotrichia leucophrys gambelii

    Directory of Open Access Journals (Sweden)

    Gang WANG, Marilyn RAMENOFSKY, John C. WINGFIELD

    2013-06-01

    Full Text Available In seasonally breeding birds, the annual cycle of photoperiod is a principal environmental cue for temporal arrangement of different life-history stages, such as migration and breeding. In the past, most research has focused on the mechanisms of photoperiodic control of breeding with less attention paid to migration. In Gambel’s white-crowned sparrow Zonotrichia leucophrys gambelii (GWCS, photoreceptors for induction of breeding are known to reside in the basal hypothalamus. However, it is unknown whether the sites of photoperiodic reception for vernal migration are the same as those for breeding. Therefore, we hypothesized that they may be controlled separately. In this study, we exposed photosensitive GWCSs to low-penetration green light (wavelength at 510 nm under a regime of 1 lux during the day and <0.1 lux at night, and switched the photoperiodic conditions from short day (10 h daytime to long day (18 h daytime. The results showed that the experimental birds developed traits associated with vernal migration including mass increase, fat deposition and migratory restlessness behavior when transferred from short day to long day green light cycles, while control birds maintained continuously on short day green light conditions did not express any migration related characteristics. Neither experimental nor control groups showed gonadal recrudescence under either green light cycles. In support of our hypothesis, we were able to apparently dissociate the photoperiodic responses regulating vernal migration and breeding, which suggests separate mechanisms of photoperiodic time measurement. Such distinct photoperiodic mechanisms may drive the fine-tuned temporal arrangement of the two life history stages [Current Zoology 59 (3: 349–359, 2013].

  11. The timing of normal puberty and the age limits of sexual precocity: variations around the world, secular trends, and changes after migration.

    Science.gov (United States)

    Parent, Anne-Simone; Teilmann, Grete; Juul, Anders; Skakkebaek, Niels E; Toppari, Jorma; Bourguignon, Jean-Pierre

    2003-10-01

    During the past decade, possible advancement in timing of puberty has been reported in the United States. In addition, early pubertal development and an increased incidence of sexual precocity have been noticed in children, primarily girls, migrating for foreign adoption in several Western European countries. These observations are raising the issues of current differences and secular trends in timing of puberty in relation to ethnic, geographical, and socioeconomic background. None of these factors provide an unequivocal explanation for the earlier onset of puberty seen in the United States. In the formerly deprived migrating children, refeeding and catch-up growth may prime maturation. However, precocious puberty is seen also in some nondeprived migrating children. Attention has been paid to the changing milieu after migration, and recently, the possible role of endocrine- disrupting chemicals from the environment has been considered. These observations urge further study of the onset of puberty as a possible sensitive and early marker of the interactions between environmental conditions and genetic susceptibility that can influence physiological and pathological processes.

  12. Novel migrating mouse neural crest cell assay system utilizing P0-Cre/EGFP fluorescent time-lapse imaging

    Directory of Open Access Journals (Sweden)

    Kawakami Minoru

    2011-11-01

    Full Text Available Abstract Background Neural crest cells (NCCs are embryonic, multipotent stem cells. Their long-range and precision-guided migration is one of their most striking characteristics. We previously reported that P0-Cre/CAG-CAT-lacZ double-transgenic mice showed significant lacZ expression in tissues derived from NCCs. Results In this study, by embedding a P0-Cre/CAG-CAT-EGFP embryo at E9.5 in collagen gel inside a culture glass slide, we were able to keep the embryo developing ex vivo for more than 24 hours; this development was with enough NCC fluorescent signal intensity to enable single-cell resolution analysis, with the accompanying NCC migration potential intact and with the appropriate NCC response to the extracellular signal maintained. By implantation of beads with absorbed platelet-derived growth factor-AA (PDGF-AA, we demonstrated that PDGF-AA acts as an NCC-attractant in embryos. We also performed assays with NCCs isolated from P0-Cre/CAG-CAT-EGFP embryos on culture plates. The neuromediator 5-hydroxytryptamine (5-HT has been known to regulate NCC migration. We newly demonstrated that dopamine, in addition to 5-HT, stimulated NCC migration in vitro. Two NCC populations, with different axial levels of origins, showed unique distribution patterns regarding migration velocity and different dose-response patterns to both 5-HT and dopamine. Conclusions Although avian species predominated over the other species in the NCC study, our novel system should enable us to use mice to assay many different aspects of NCCs in embryos or on culture plates, such as migration, division, differentiation, and apoptosis.

  13. College Student Migration.

    Science.gov (United States)

    Fenske, Robert H.; And Others

    This study examines the background characteristics of two large national samples of first-time enrolled freshmen who (a) attended college within their state of residence but away from their home community, (b) migrated to a college in an adjacent state, (c) migrated to a college in a distant state, and (d) attended college in their home community.…

  14. Effects of Changes in Food Supply at the Time of Sex Differentiation on the Gonadal Transcriptome of Juvenile Fish. Implications for Natural and Farmed Populations

    OpenAIRE

    Díaz, Noelia; Ribas, Laia; Piferrer, Francesc

    2014-01-01

    Background: Food supply is a major factor influencing growth rates in animals. This has important implications for both natural and farmed fish populations, since food restriction may difficult reproduction. However, a study on the effects of food supply on the development of juvenile gonads has never been transcriptionally described in fish. Methods and Findings: This study investigated the consequences of growth on gonadal transcriptome of European sea bass in: 1) 4-month-old sexually undif...

  15. Juvenile-specific cathepsin proteases in Fasciola spp.: their characteristics and vaccine efficacies.

    Science.gov (United States)

    Meemon, Krai; Sobhon, Prasert

    2015-08-01

    Fasciolosis, caused by Fasciola hepatica and Fasciola gigantica, is one of the most neglected tropical zoonotic diseases. One sustainable control strategy against these infections is the employment of vaccines that target proteins essential for parasites' invasion and nutrition acquiring processes. Cathepsin proteases are the most abundantly expressed proteins in Fasciola spp. that have been tested successfully as vaccines against fasciolosis in experimental as well as large animals because of their important roles in digestion of nutrients, invasion, and migration. Specifically, juvenile-specific cathepsin proteases are the more effective vaccines because they could block the invasion and migration of juvenile parasites whose immune evasion mechanism has not yet been fully developed. Moreover, because of high sequence similarity and identity of cathepsins from juveniles with those of adults, the vaccines can attack both the juvenile and adult stages. In this article, the characteristics and vaccine potentials of juvenile-specific cathepsins, i.e., cathepsins L and B, of Fasciola spp. were reviewed.

  16. Juvenil idiopatisk arthritis

    DEFF Research Database (Denmark)

    Herlin, Troels

    2002-01-01

    The new classification of juvenile idiopathic arthritis (JIA) is described in this review. Clinical characteristics divide JIA in to subtypes: systemic, oligoarticular (persistent and extended type), RF-positive and--negative polyarticular, enthesitis-related arthritis and psoriatic arthritis...

  17. Juvenile Rockfish Recruitment Cruise

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In 1983, the groundfish analysis project began a series of yearly cruises designed to assess the annual abundance of juvenile rockfish along the central California...

  18. Juvenile Justice in Mexico

    Directory of Open Access Journals (Sweden)

    Martha Frías Armenta

    2014-08-01

    Full Text Available The first tribunal in Mexico was established in the central state of San Luis Potosi in 1926. The Law Regarding Social Prevention and Juvenile Delinquency for the Federal District and Mexican territories was promulgated in 1928. In 2005, Article 18 of the Mexican Constitution was modified to establish a comprehensive system (“Sistema Integral de justicia” in Spanish of justice for juveniles between 12 and 18 years old who had committed a crime punishable under criminal law. Its objective was to guarantee juveniles all the due process rights established for adults, in addition to the special ones recognized for minors. The constitutional reform also provides a framework that includes special tribunals as well as alternative justice options for juveniles. With these reforms, institutionalization of minors was to be considered an extreme measure applicable only to felonies and to juveniles older than 14. In 2006, all states within the Mexican federation enacted the “Law of justice for adolescents”. This system, at both the federal and state levels, formalizes a new global paradigm with regard to the triangular relationship between children, the State and the Law. It recognizes that children are also bearers of the inherent human rights recognized for all individuals, instead of simply objects in need of protection. However, despite formally aligning Mexican juvenile justice law with the Convention on the Rights of the Child (CRC, issues of actual substantive rights remained and new ones have appeared. For example, juveniles younger than 14 who have not committed a felony are released from institutions without any rehabilitation or treatment options, and alternative forms of justice were included without evaluating their possibilities of application or their conditions for success. In addition, the economic status of most juvenile detainees continues to be one of the most important determining factors in the administration of justice

  19. Juvenile polyposis syndrome

    OpenAIRE

    Hsiao, Yi-Han; Wei, Chin-Hung; Chang, Szu-Wen; Chang, Lung; Fu, Yu-Wei; Lee, Hung-Chang; Liu, Hsuan-Liang; Yeung, Chun-Yan

    2016-01-01

    Abstract Background: Juvenile polyposis syndrome, a rare disorder in children, is characterized with multiple hamartomatous polyps in alimentary tract. A variety of manifestations include bleeding, intussusception, or polyp prolapse. In this study, we present an 8-month-old male infant of juvenile polyposis syndrome initially presenting with chronic anemia. To the best of our knowledge, this is the youngest case reported in the literature. Methods: We report a rare case of an 8-month-old male...

  20. Parenting and juvenile delinquency

    OpenAIRE

    Hoeve, M.

    2008-01-01

    Juvenile delinquency is a noteworthy problem. This thesis addressed the association between parenting and juvenile delinquency by analyzing the concepts of parenting adopted in family research in relation to criminological concepts and measures of delinquent behavior. Four studies were conducted. The first study addressed a meta-analysis on parenting characteristics and styles in relation to delinquency. In this meta-analysis, previous manuscripts were systematically analyzed, computing mean ...

  1. Registration accuracy and possible migration of internal fiducial gold marker implanted in prostate and liver treated with real-time tumor-tracking radiation therapy (RTRT)

    International Nuclear Information System (INIS)

    Kitamura, Kei; Shirato, Hiroki; Shimizu, Shinichi; Shinohara, Nobuo; Harabayashi, Toru; Shimizu, Tadashi; Kodama, Yoshihisa; Endo, Hideho; Onimaru, Rikiya; Nishioka, Seiko; Aoyama, Hidefumi; Tsuchiya, Kazuhiko; Miyasaka, Kazuo

    2002-01-01

    Background and purpose: We have developed a linear accelerator synchronized with a fluoroscopic real-time tumor-tracking system to reduce errors due to setup and organ motion. In the real-time tumor-tracking radiation therapy (RTRT) system, the accuracy of tumor tracking depends on the registration of the marker's coordinates. The registration accuracy and possible migration of the internal fiducial gold marker implanted into prostate and liver was investigated. Materials and methods: Internal fiducial gold markers were implanted in 14 patients with prostate cancer and four patients with liver tumors. Computed tomography (CT) was carried out as a part of treatment planning in the 18 patients. A total of 72 follow-up CT scans were taken. We calculated the relative relationship between the coordinates of the center of mass (CM) of the organs and those of the marker. The discrepancy in the CM coordinates during a follow-up CT compared to those recorded during the planning CT was used to study possible marker migration. Results: The standard deviation (SD) of interobserver variations in the CM coordinates was within 2.0 and 0.4 mm for the organ and the marker, respectively, in seven observers. Assuming that organs do not shrink, grow, or rotate, the maximum SD of migration error in each direction was estimated to be less than 2.5 and 2.0 mm for liver and prostate, respectively. There was no correlation between the marker position and the time after implantation. Conclusion: The degree of possible migration of the internal fiducial marker was within the limits of accuracy of the CT measurement. Most of the marker movement can be attributed to the measurement uncertainty, which also influences registration in actual treatment planning. Thus, even with the gold marker and RTRT system, a planning target volume margin should be used to account for registration uncertainty

  2. Candidate genes have sex-specific effects on timing of spring migration and moult speed in a long-distance migratory bird.

    Science.gov (United States)

    Bazzi, Gaia; Podofillini, Stefano; Gatti, Emanuele; Gianfranceschi, Luca; Cecere, Jacopo G; Spina, Fernando; Saino, Nicola; Rubolini, Diego

    2017-10-01

    The timing of major life-history events, such as migration and moult, is set by endogenous circadian and circannual clocks, that have been well characterized at the molecular level. Conversely, the genetic sources of variation in phenology and in other behavioral traits have been sparsely addressed. It has been proposed that inter-individual variability in the timing of seasonal events may arise from allelic polymorphism at phenological candidate genes involved in the signaling cascade of the endogenous clocks. In this study of a long-distance migratory passerine bird, the willow warbler Phylloscopus trochilus , we investigated whether allelic variation at 5 polymorphic loci of 4 candidate genes ( Adcyap1 , Clock , Creb1 , and Npas2 ), predicted 2 major components of the annual schedule, namely timing of spring migration across the central Mediterranean sea and moult speed, the latter gauged from ptilochronological analyses of tail feathers moulted in the African winter quarters. We identified a novel Clock gene locus ( Clock region 3) showing polyQ polymorphism, which was however not significantly associated with any phenotypic trait. Npas2 allele size predicted male (but not female) spring migration date, with males bearing longer alleles migrating significantly earlier than those bearing shorter alleles. Creb1 allele size significantly predicted male (but not female) moult speed, longer alleles being associated with faster moult. All other genotype-phenotype associations were statistically non-significant. These findings provide new evidence for a role of candidate genes in modulating the phenology of different circannual activities in long-distance migratory birds, and for the occurrence of sex-specific candidate gene effects.

  3. Effects of changes in food supply at the time of sex differentiation on the gonadal transcriptome of juvenile fish. Implications for natural and farmed populations.

    Directory of Open Access Journals (Sweden)

    Noelia Díaz

    Full Text Available Food supply is a major factor influencing growth rates in animals. This has important implications for both natural and farmed fish populations, since food restriction may difficult reproduction. However, a study on the effects of food supply on the development of juvenile gonads has never been transcriptionally described in fish.This study investigated the consequences of growth on gonadal transcriptome of European sea bass in: 1 4-month-old sexually undifferentiated fish, comparing the gonads of fish with the highest vs. the lowest growth, to explore a possible link between transcriptome and future sex, and 2 testis from 11-month-old juveniles where growth had been manipulated through changes in food supply. The four groups used were: i sustained fast growth, ii sustained slow growth, iii accelerated growth, iv decelerated growth. The transcriptome of undifferentiated gonads was not drastically affected by initial natural differences in growth. Further, changes in the expression of genes associated with protein turnover were seen, favoring catabolism in slow-growing fish and anabolism in fast-growing fish. Moreover, while fast-growing fish took energy from glucose, as deduced from the pathways affected and the analysis of protein-protein interactions examined, in slow-growing fish lipid metabolism and gluconeogenesis was favored. Interestingly, the highest transcriptomic differences were found when forcing initially fast-growing fish to decelerate their growth, while accelerating growth of initially slow-growing fish resulted in full transcriptomic convergence with sustained fast-growing fish.Food availability during sex differentiation shapes the juvenile testis transcriptome, as evidenced by adaptations to different energy balances. Remarkably, this occurs in absence of major histological changes in the testis. Thus, fish are able to recover transcriptionally their testes if they are provided with enough food supply during sex

  4. Effects of changes in food supply at the time of sex differentiation on the gonadal transcriptome of juvenile fish. Implications for natural and farmed populations.

    Science.gov (United States)

    Díaz, Noelia; Ribas, Laia; Piferrer, Francesc

    2014-01-01

    Food supply is a major factor influencing growth rates in animals. This has important implications for both natural and farmed fish populations, since food restriction may difficult reproduction. However, a study on the effects of food supply on the development of juvenile gonads has never been transcriptionally described in fish. This study investigated the consequences of growth on gonadal transcriptome of European sea bass in: 1) 4-month-old sexually undifferentiated fish, comparing the gonads of fish with the highest vs. the lowest growth, to explore a possible link between transcriptome and future sex, and 2) testis from 11-month-old juveniles where growth had been manipulated through changes in food supply. The four groups used were: i) sustained fast growth, ii) sustained slow growth, iii) accelerated growth, iv) decelerated growth. The transcriptome of undifferentiated gonads was not drastically affected by initial natural differences in growth. Further, changes in the expression of genes associated with protein turnover were seen, favoring catabolism in slow-growing fish and anabolism in fast-growing fish. Moreover, while fast-growing fish took energy from glucose, as deduced from the pathways affected and the analysis of protein-protein interactions examined, in slow-growing fish lipid metabolism and gluconeogenesis was favored. Interestingly, the highest transcriptomic differences were found when forcing initially fast-growing fish to decelerate their growth, while accelerating growth of initially slow-growing fish resulted in full transcriptomic convergence with sustained fast-growing fish. Food availability during sex differentiation shapes the juvenile testis transcriptome, as evidenced by adaptations to different energy balances. Remarkably, this occurs in absence of major histological changes in the testis. Thus, fish are able to recover transcriptionally their testes if they are provided with enough food supply during sex differentiation; however

  5. Oxidative stress and partial migration in brown trout (Salmo trutta)

    DEFF Research Database (Denmark)

    Birnie-Gauvin, Kim; Peiman, K. S.; Larsen, Martin Hage

    2017-01-01

    of oxidative status in migration biology, particularly in fish. Semi-anadromous brown trout (Salmo trutta, Linnaeus 1758) exhibit partial migration, where some individuals smoltify and migrate to sea, and others become stream residents, providing us with an excellent model to investigate the link between...... oxidative stress and migration. Using the brown trout, we obtained blood samples from juveniles from a coastal stream in Denmark in the fall prior to peak seaward migration which occurs in the spring, and assayed for antioxidant capacity (oxygen radical absorbance capacity) and oxidative stress levels...

  6. Fetal and juvenile radiotoxicity

    International Nuclear Information System (INIS)

    Sikov, M.R.

    1982-01-01

    This project is directed at obtaining detailed comparative information on the deposition, distribution, retention, and toxicity of radionuclides in the prenatal and juvenile mammal. Because quantitative data cannot necessarily be extrapolated to man, our emphasis is directed toward establishing patterns, phenomenologic interactions, and relationships which will be useful in determining appropriate exposure levels for the rapidly growing infant or child, and for pregnant women. Recent results demonstrated that injection of pregnant rats with 23 Pu had the greatest effect on longevity and bone-tumor incidence of the offspring when exposure occurred at 19 days of gestation (dg); less effect at 15 dg and the least effect at 9 dg. Ongoing distribution studies are providing data which confirm our tentative explanation that marked variations in the anatomic distributions of bone tumors, with age at the time of injection, were attributable to age-related differences in 239 Pu microdosimetry and concentrations among skeletal components. Other studies, using a placental perfusion technique, have demonstrated that intravenous injection of 239 Pu in pregnant guinea pigs leads to a marked decrease in maternal blood flow to the placenta

  7. The anchor of the frameless intrauterine device does not migrate over time: an analysis in over 300 women

    Directory of Open Access Journals (Sweden)

    Wildemeersch D

    2014-12-01

    Full Text Available Dirk Wildemeersch,1 Ansgar Pett,2 Sohela Jandi,2 Kilian Nolte,3 Wolfgang Albrecht4 1Gynecological Outpatient Clinic and IUD Training Centre, Ghent, Belgium; 2Gynecological Outpatient Clinic, Berlin, Germany; 3Gynecological Outpatient Clinic, Uetze, Germany; 4Gynecological Outpatient Clinic, Feldkirchen, Austria Objective: To evaluate the correct position of the anchor at insertion and follow-up and assess if migration of the anchor occurs over time. Materials and methods: This was an insertion-related, prospective, postmarketing study in 309 women. Following insertion, women were followed up at 4–6 weeks, 6 months, and yearly thereafter. The position of the visualized anchor in the fundus of the uterus was evaluated using ultrasound by measuring its distance from the serosal surface of the uterus (SA-distance. Results: A total of 309 parous (n=115 and nulliparous (n=194 women were fitted with the frameless GyneFix 200 or the GyneFix 330 intrauterine device for contraception. The mean SA-distance in 306 parous and nulliparous women was 6.0 mm (range 2.0–24.0 mm at insertion in the parous group and 5.4 mm (range 1.3–11.0 mm in the nulliparous group. At the first follow-up in 281 women, the SA-distance was 6.0 mm (range 2.0–12.0 mm in the parous group and 5.5 mm (range 1.1–11.0 mm in the nulliparous group. The SA-distance was not significantly different. One patient had an exceptionally large SA-distance of 24 mm, probably due to insertion in the posterior wall. No follow-up could be done in this patient. In 77 women, the SA-distance was measured up to 42 months. The mean SA-distance at insertion in the parous group was 5.2 mm (range 3.0–8.5 mm and 4.8 mm (range 1.3–7.0 mm in the nulliparous group. At the last follow-up up to 36 months or longer, the SA-distance was 5.1 mm (range 3.0–8.5 mm in the parous group and 4.9 mm (range 1.3–7.0 mm in the nulliparous group. The SA-distance was not significantly different. The visualized

  8. Temporal migration patterns between natal locations of ruby-throated hummingbirds (Archilochus colubris) and their Gulf Coast stopover site.

    Science.gov (United States)

    Zenzal, Theodore J; Contina, Andrea J; Kelly, Jeffrey F; Moore, Frank R

    2018-01-01

    Autumn latitudinal migrations generally exhibit one of two different temporal migration patterns: type 1 where southern populations migrate south before northern populations, or type 2 where northern populations overtake southern populations en route . The ruby-throated hummingbird ( Archilochus colubris ) is a species with an expansive breeding range, which allows opportunities to examine variation in the timing of migration. Our objective was to determine a relationship between natal origin of ruby-throated hummingbirds and arrival at a Gulf coast stopover site; and if so, what factors, such as differences in body size across the range as well as the cost of migration, might drive such a pattern. To carry out our objectives, we captured hummingbirds at a coastal stopover site during autumn migration, at which time we collected feathers from juveniles for analysis of hydrogen stable isotopes. Using the hydrogen stable isotope gradient of precipitation across North America and published hydrogen isotope values of feathers from populations of breeding ruby-throated hummingbirds, we assigned migrants to probable natal latitudes. Our results confirm that individuals from across the range (30-50° N) stopover along the Gulf of Mexico and there is a positive relationship between arrival day and latitude, suggesting a type 1 migration pattern. We also found no relationship between fuel load (proxy for migration cost) or fat-free body mass (proxy for body size) and natal latitude. Our results, coupled with previous work on the spatial migration patterns of hummingbirds, show a type 1 chain migration pattern. While the mechanisms we tested do not seem to influence the evolution of migratory patterns, other factors such as resource availability may play a prominent role in the evolution of this migration system.

  9. Imaging subsurface migration of dissolved CO2 in a shallow aquifer using 3-D time-lapse electrical resistivity tomography

    DEFF Research Database (Denmark)

    Auken, Esben; Doetsch, Joseph; Fiandaca, Gianluca

    2014-01-01

    Contamination of groundwater by leaking CO2 is a potential risk of carbon sequestration. With the help of a field experiment in western Denmark, we investigate to what extent surface electrical resistivity tomography (ERT) can detect and image dissolved CO2 in a shallow aquifer. For this purpose...... the injection start. During these 120days, the CO2 migrates about 25m in the expected groundwater flow direction. Water electrical conductivity (EC) sampling using small screens in 29 wells allows for very good verification of the ERT results. Water EC and ERT results generally agree very well, with the water...

  10. Delinquency Cases in Juvenile Court, 2002. OJJDP Fact Sheet #02

    Science.gov (United States)

    Stahl, Anne L.

    2006-01-01

    This fact sheet presents statistics on delinquency cases processed by juvenile courts in 2002. The number of delinquency cases handled by juvenile courts decreased 11 percent between 1997 and 2002. During this time, the number of person offense cases decreased 2 percent, property offense cases decreased 27 percent, drug law violation cases…

  11. Gas bubble disease monitoring and research of juvenile salmonids

    International Nuclear Information System (INIS)

    Maule, A.G.; Beeman, J.; Hans, K.M.; Mesa, M.G.; Haner, P.; Warren, J.J.

    1997-10-01

    This document describes the project activities 1996--1997 contract year. This report is composed of three chapters which contain data and analyses of the three main elements of the project: field research to determine the vertical distribution of migrating juvenile salmonids, monitoring of juvenile migrants at dams on the Snake and Columbia rivers, and laboratory experiments to describe the progression of gas bubble disease signs leading to mortality. The major findings described in this report are: A miniature pressure-sensitive radio transmitter was found to be accurate and precise and, after compensation for water temperature, can be used to determine the depth of tagged-fish to within 0.32 m of the true depth (Chapter 1). Preliminary data from very few fish suggest that depth protects migrating juvenile steelhead from total dissolved gas supersaturation (Chapter 1). As in 1995, few fish had any signs of gas bubble disease, but it appeared that prevalence and severity increased as fish migrated downstream and in response to changing gas supersaturation (Chapter 2). It appeared to gas bubble disease was not a threat to migrating juvenile salmonids when total dissolved gas supersaturation was < 120% (Chapter 2). Laboratory studies suggest that external examinations are appropriate for determining the severity of gas bubble disease in juvenile salmonids (Chapter 3). The authors developed a new method for examining gill arches for intravascular bubbles by clamping the ventral aorta to reduce bleeding when arches were removed (Chapter 3). Despite an outbreak of bacterial kidney disease in the experimental fish, the data indicate that gas bubble disease is a progressive trauma that can be monitored (Chapter 3)

  12. Stress and food deprivation: linking physiological state to migration success in a teleost fish.

    Science.gov (United States)

    Midwood, Jonathan D; Larsen, Martin H; Aarestrup, Kim; Cooke, Steven J

    2016-12-01

    Food deprivation is a naturally occurring stressor that is thought to influence the ultimate life-history strategy of individuals. Little is known about how food deprivation interacts with other stressors to influence migration success. European populations of brown trout (Salmo trutta) exhibit partial migration, whereby a portion of the population smoltifies and migrates to the ocean, and the rest remain in their natal stream. This distinct, natural dichotomy of life-history strategies provides an excellent opportunity to explore the roles of energetic state (as affected by food deprivation) and activation of the glucocorticoid stress response in determining life-history strategy and survival of a migratory species. Using an experimental approach, the relative influences of short-term food deprivation and experimental cortisol elevation (i.e. intra-coelomic injection of cortisol suspended in cocoa butter) on migratory status, survival and growth of juvenile brown trout relative to a control were evaluated. Fewer fish migrated in both the food deprivation and cortisol treatments; however, migration of fish in cortisol and control treatments occurred at the same time while that of fish in the food deprivation treatment was delayed for approximately 1 week. A significantly greater proportion of trout in the food deprivation treatment remained in their natal stream, but unlike the cortisol treatment, there were no long-term negative effects of food deprivation on growth, relative to the control. Overall survival rates were comparable between the food deprivation and control treatments, but significantly lower for fish in the cortisol treatment. Food availability and individual energetic state appear to dictate the future life-history strategy (migrate or remain resident) of juvenile salmonids while experimental elevation of the stress hormone cortisol causes impaired growth and reduced survival of both resident and migratory individuals. © 2016. Published by The

  13. Estudio de la migración y de la actividad metabólica de los polimofonucleares neutrófilos en pacientes con periodontitis juvenil localizada Migration and metabolic activity of polymorphonuclear neutrophils in patients with localized juvenile periodontitis

    Directory of Open Access Journals (Sweden)

    Pablo Javier Patiño Grajales

    1993-03-01

    Full Text Available La periodontitis juvenil localizada (PJL se caracteriza por presentar una pérdida rápida de la inserción del tejido conectivo y el hueso alveolar alrededor de los primeros molares e incisivos de la dentición permanente. Esta Investigación se realizó para establecer una relación entre el comportamiento In vitro de los polimorfonucleares neutrófilos (PMN y los diferentes tipos clínicos de la enfermedad. Se estudiaron 21 pacientes con PJL clasificados en tres grupos: incipiente, moderada y avanzada. Antes de que los pacientes recibieran algún tipo de tratamiento odontológico, se les aislaron los neutrófilos y se estudió, In vitro, la quimiotaxis bajo agarosa y la actividad metabólica mediante la quimioluminiscencia dependiente de luminol (QLDL. Las mismas pruebas fueron practicadas en forma paralela a un grupo de individuos sanos como controles. Los pacientes con PJL avanzada tuvieron una disrninución significativa de la quimiotaxis (p=0.023. Su índice quimiotáctico fue de 9.4 :t 1.01 mientras el de los controles fue 11.9 :t 0.33. De otro lado, la QLDL de los PMN estimulados con forbol miristato acetato (PMA fue normal en todos los grupos, comparados con los controles; en contraste la estimulación de los PMN con zymosan opsonizado, evidenció una actividad metabólica significativamente disminuida en los pacientes con PJL incipiente y avanzada: el promedio de producción de energía lumínica en cpm para el grupo con PJL avanzada fue 703376:!: 74510 y para el de PJL incipiente fue 737000:!: 168610; en contraste en el grupo control fue 916597:!: 47418 (p=0.012. Estos hallazgos revelan que los pacientes con PJL conforman un grupo heterogéneo en cuanto a la función de los PMN. Para esclarecer la respuesta de los PMN en cada tipo de PJL, se hace necesario estudiar la vinculación entre los componentes genéticos, el medio ambiente y los fenotipos clínicos de la enfermedad.

    Corporal and capital punishment of juveniles.

    Science.gov (United States)

    Frazier, H C

    1990-01-01

    There is a previously unobserved connection between corporal punishment of public school children and capital punishment of juveniles. Both are barometers of acceptable levels of violent punishment and their elimination is a hallmark of a maturing and decent society. Within a majority of the eighteen states where school authorities most frequently strike children are housed 25 of the nation's 28 juvenile death row inmates. On average, the homicide rates of these jurisdictions are two and a half times greater than those that have abolished both state-sanctioned corporal and capital punishment or limit death sentences to those age eighteen and older at the time of their crime(s). Most of the eighteen state abolitions of corporal punishment occurred in the 1980's. The US Supreme Court has ruled both corporal and capital punishment of juveniles constitutional. Additional state legislative abolition of both is anticipated in the 1990s.

  14. Extending juvenility in grasses

    Energy Technology Data Exchange (ETDEWEB)

    Kaeppler, Shawn; de Leon Gatti, Natalia; Foerster, Jillian

    2017-04-11

    The present invention relates to compositions and methods for modulating the juvenile to adult developmental growth transition in plants, such as grasses (e.g. maize). In particular, the invention provides methods for enhancing agronomic properties in plants by modulating expression of GRMZM2G362718, GRMZM2G096016, or homologs thereof. Modulation of expression of one or more additional genes which affect juvenile to adult developmental growth transition such as Glossy15 or Cg1, in conjunction with such modulation of expression is also contemplated. Nucleic acid constructs for down-regulation of GRMZM2G362718 and/or GRMZM2G096016 are also contemplated, as are transgenic plants and products produced there from, that demonstrate altered, such as extended juvenile growth, and display associated phenotypes such as enhanced yield, improved digestibility, and increased disease resistance. Plants described herein may be used, for example, as improved forage or feed crops or in biofuel production.

  15. Miastenia gravis juvenil Juvenile myasthenia gravis

    OpenAIRE

    Oscar Papazian; Israel Alfonso; Nayle Araguez

    2009-01-01

    La miastenia gravis juvenil (MGJ) es un trastorno crónico auto inmune en el cual existen anticuerpos séricos que al unirse a los receptores de acetilcolin nicotínicos de la membrana muscular de la placa motora alteran la transmisión neuromuscular. El resultado es fatiga muscular precoz con progresión a la parálisis durante estados de contracción muscular iterativos (movimientos) o sostenidos (posturas) y más raramente parálisis permanente durante el reposo. Los músculos inervados por los nerv...

  16. Criminal history and future offending of juveniles convicted of the possession of child pornography.

    Science.gov (United States)

    Aebi, Marcel; Plattner, Belinda; Ernest, Melanie; Kaszynski, Katie; Bessler, Cornelia

    2014-08-01

    Most child pornography is distributed online. It is estimated that 3% to 15% of child pornography consumers are juveniles. The present study analyzed a consecutive sample of 54 male juveniles convicted of the possession of child pornography. Demographic characteristics, criminal history, and subsequent offending were assessed from criminal files and official reports. Juvenile possessors of child pornography were compared to three different groups of juveniles: Juvenile possessors of other illegal pornography (n = 42), juveniles who committed a sexual contact offense against a child (n = 64), and juveniles who committed a sexual contact offense against a peer or adult (n = 104). Juvenile possessors of child pornography were found to have downloaded the illegal material more frequently and over a longer time period than juvenile possessors of other illegal pornography. Furthermore, juvenile possessors of child pornography differed from juveniles who had committed a sexual contact offense in terms of demographics and showed fewer previous and subsequent offending than juveniles who sexually offended against a peer or adult. We conclude that juvenile possessors of child pornography need a specific target intervention focusing on dysfunctional Internet use and sexually deviant arousal. © The Author(s) 2013.

  17. DERMATOMIOSITIS JUVENIL Y EMBARAZO

    OpenAIRE

    Evans M,Gregorio; Poulsen R,Ronald; Blanco R,Romiely; Luna V,Viviana

    2002-01-01

    La dermatomiositis juvenil es un desorden inflamatorio crónico multisistémico del tejido conectivo. Tiene una incidencia de 2-3/100.000/año. Con la disminución en la mortalidad experimentada en los últimos decenios, la atención está cifrada en la morbilidad a largo plazo y en las alteraciones funcionales. Con un tratamiento agresivo los niños con dermatomiositis juvenil generalmente tienen un futuro promisorio, sin incapacidad o con incapacidad mínima. La mortalidad actualmente se estima cerc...

  18. Monitoring the evolution and migration of a methane gas plume in an unconfined sandy aquifer using time-lapse GPR and ERT.

    Science.gov (United States)

    Steelman, Colby M; Klazinga, Dylan R; Cahill, Aaron G; Endres, Anthony L; Parker, Beth L

    2017-10-01

    Fugitive methane (CH 4 ) leakage associated with conventional and unconventional petroleum development (e.g., shale gas) may pose significant risks to shallow groundwater. While the potential threat of stray (CH 4 ) gas in aquifers has been acknowledged, few studies have examined the nature of its migration and fate in a shallow groundwater flow system. This study examines the geophysical responses observed from surface during a 72day field-scale simulated CH 4 leak in an unconfined sandy aquifer at Canadian Forces Base Borden, Canada, to better understand the transient behaviour of fugitive CH 4 gas in the subsurface. Time-lapse ground-penetrating radar (GPR) and electrical resistivity tomography (ERT) were used to monitor the distribution and migration of the gas-phase and assess any impacts to groundwater hydrochemistry. Geophysical measurements captured the transient formation of a CH 4 gas plume emanating from the injector, which was accompanied by an increase in total dissolved gas pressure (P TDG ). Subsequent reductions in P TDG were accompanied by reduced bulk resistivity around the injector along with an increase in the GPR reflectivity along horizontal bedding reflectors farther downgradient. Repeat temporal GPR reflection profiling identified three events with major peaks in reflectivity, interpreted to represent episodic lateral CH 4 gas release events into the aquifer. Here, a gradual increase in P TDG near the injector caused a sudden lateral breakthrough of gas in the direction of groundwater flow, causing free-phase CH 4 to migrate much farther than anticipated based on groundwater advection. CH 4 accumulated along subtle permeability boundaries demarcated by grain-scale bedding within the aquifer characteristic of numerous Borden-aquifer multi-phase flow experiments. Diminishing reflectivity over a period of days to weeks suggests buoyancy-driven migration to the vadose zone and/or CH 4 dissolution into groundwater. Lateral and vertical CH 4

  19. Differential heritability of adult and juvenile antisocial traits.

    Science.gov (United States)

    Lyons, M J; True, W R; Eisen, S A; Goldberg, J; Meyer, J M; Faraone, S V; Eaves, L J; Tsuang, M T

    1995-11-01

    Studies of adult antisocial behavior or criminality usually find genetic factors to be more important than the family environment, whereas studies of delinquency find the family environment to be more important. We compared DSM-III-R antisocial personality disorder symptoms before vs after the age of 15 years within a sample of twins, rather than comparing across studies. We administered the Diagnostic Interview Schedule Version III-revised by telephone to 3226 pairs of male twins from the Vietnam Era Twin Registry. Biometrical modeling was applied to each symptom of antisocial personality disorder and summary measures of juvenile and adult symptoms. Five juvenile symptoms were significantly heritable, and five were significantly influenced by the shared environment. Eight adult symptoms were significantly heritable, and one was significantly influenced by the shared environment. The shared environment explained about six times more variance in juvenile anti-social traits than in adult traits. Shared environmental influences on adult antisocial traits overlapped entirely with those on juvenile traits. Additive genetic factors explained about six times more variance in adult vs juvenile traits. The juvenile genetic determinants overlapped completely with genetic influences on adult traits. The unique environment (plus measurement error) explained the largest proportion of variance in both juvenile and adult antisocial traits. Characteristics of the shared or family environment that promote antisocial behavior during childhood and early adolescence also promote later antisocial behavior, but to a much lesser extent. Genetic causal factors are much more prominent for adult than for juvenile antisocial traits.

  1. Family transitions and juvenile delinquency.

    Science.gov (United States)

    Schroeder, Ryan D; Osgood, Aurea K; Oghia, Michael J

    2010-01-01

    There is a large body of research that shows children from non-intact homes show higher rates of juvenile delinquency than children from intact homes, partially due to weaker parental control and supervision in non-intact homes. What has not been adequately addressed in the research is the influence of changes in family structure among individual adolescents over time on delinquent offending. Using the first and third waves of the National Youth Study, we assess the effect of family structure changes on changes in delinquent offending between waves through the intermediate process of changes in family time and parental attachment. Although prior research has documented adolescents in broken homes are more delinquent than youth in intact homes, the process of family dissolution is not associated with concurrent increases in offending. In contrast, family formation through marriage or cohabitation is associated with simultaneous increases in offending. Changes in family time and parental attachment account for a portion of the family formation effect on delinquency, and prior parental attachment and juvenile offending significantly condition the effect of family formation on offending.

  2. A dynamic real time in vivo and static ex vivo analysis of granulomonocytic cell migration in the collagen-induced arthritis model.

    Directory of Open Access Journals (Sweden)

    Ruth Byrne

    Full Text Available Neutrophilic granulocytes and monocytes (granulomonocytic cells; GMC drive the inflammatory process at the earliest stages of rheumatoid arthritis (RA. The migratory behavior and functional properties of GMC within the synovial tissue are, however, only incompletely characterized. Here we have analyzed GMC in the murine collagen-induced arthritis (CIA model of RA using multi-photon real time in vivo microscopy together with ex vivo analysis of GMC in tissue sections.GMC were abundant as soon as clinical arthritis was apparent. GMC were motile and migrated randomly through the synovial tissue. In addition, we observed the frequent formation of cell clusters consisting of both neutrophilic granulocytes and monocytes that actively contributed to the inflammatory process of arthritis. Treatment of animals with a single dose of prednisolone reduced the mean velocity of cell migration and diminished the overall immigration of GMC.In summary, our study shows that the combined application of real time in vivo microscopy together with elaborate static post-mortem analysis of GMC enables the description of dynamic migratory characteristics of GMC together with their precise location in a complex anatomical environment. Moreover, this approach is sensitive enough to detect subtle therapeutic effects within a very short period of time.

  3. Juvenile polyposis syndrome

    Science.gov (United States)

    Hsiao, Yi-Han; Wei, Chin-Hung; Chang, Szu-Wen; Chang, Lung; Fu, Yu-Wei; Lee, Hung-Chang; Liu, Hsuan-Liang; Yeung, Chun-Yan

    2016-01-01

    Abstract Background: Juvenile polyposis syndrome, a rare disorder in children, is characterized with multiple hamartomatous polyps in alimentary tract. A variety of manifestations include bleeding, intussusception, or polyp prolapse. In this study, we present an 8-month-old male infant of juvenile polyposis syndrome initially presenting with chronic anemia. To the best of our knowledge, this is the youngest case reported in the literature. Methods: We report a rare case of an 8-month-old male infant who presented with chronic anemia and gastrointestinal bleeding initially. Panendoscopy and abdominal computed tomography showed multiple polyposis throughout the entire alimentary tract leading to intussusception. Technetium-99m-labeled red blood cell (RBC) bleeding scan revealed the possibility of gastrointestinal tract bleeding in the jejunum. Histopathological examination on biopsy samples showed Peutz-Jeghers syndrome was excluded, whereas the diagnosis of juvenile polyposis syndrome was established. Results: Enteroscopic polypectomy is the mainstay of the treatment. However, polyps recurred and occupied the majority of the gastrointestinal tract in 6 months. Supportive management was given. The patient expired for severe sepsis at the age of 18 months. Conclusion: Juvenile polyposis syndrome is an inherited disease, so it is not possible to prevent it. Concerning of its poor outcome and high mortality rate, it is important that we should increase awareness and education of the parents at its earliest stages. PMID:27631205

  4. [ABOUT JUVENILE NASOPHARYNGEAL ANGIOFIBROMA].

    Science.gov (United States)

    Urbain, V; Meunier, P; Otto, B

    2015-09-01

    We report the case of a young man with a juvenile nasopharyngeal angiofibroma. In this paper, we will first remind the clinical signs of this pathology and its radiological appearance (localisation and extensions). Then we will explain how radioembolisation techniques were used to facilitate the surgical intervention. Finally we will discuss the histology of this tumor.

  5. Naevoxanthoendothelioma (Synonym: Juvenile Xanthogranuloma

    Directory of Open Access Journals (Sweden)

    F Handa

    1978-01-01

    Full Text Available A case of naevoxanthoendothelioma juvenile xanthogranuloma is reported with rare features like late onset of the disease, involvement of liver and diffuse cutaneous lesions including cafe au lait spots and pigmented naevus. Final diagnosis could be achieved only on histopathology report.

  6. Early migration and estuary stopover of introduced chinook salmon population in the Lapataia River Basin, southern Tierra del Fuego Island

    Science.gov (United States)

    Chalde, T.; Fernández, D. A.

    2017-12-01

    Established populations of chinook salmon (Oncorhynchus tshawytscha) have recently been reported in South America, at both Atlantic and Pacific basins. Several studies have evaluated different aspects of their life histories; however, little is known about the use of the estuaries by the juveniles of these populations. We examined spawning time, seaward migration timing, growth rate, scale patterns, diet, and geometric morphometric, contrasting the early life history during freshwater and estuary residence of a chinook population established in Lapataia Basin. Fall run spawning took place in March-April and the parr emerged in September. Two distinct seaward migration patterns were identified from sein net fishing records: one population segment migrating earlier to the estuary in October and a second group migrating later in February. The growth rate of fish captured at the estuary was significantly higher than the fish captured in freshwater. In addition, higher scale intercirculi distances were observed in estuary fish showing differences in growth rate. The feeding habitat in fish captured in both environments changed through time from bottom feeding to surface feeding and from significant diet overlap to no overlap. The morphology of the fish captured at the estuary was associated with the elongation of the caudal peduncle and a decrease in the condition factor index, both changes related to smolt transformation. The earlier migration and the higher growth rate of juveniles in the estuary together with fish of 1 + yo captured in this environment reveal that the estuary of Lapataia Basin is not only a stopover for the chinook salmon, but also a key habitat to reside and feed previous to the final seaward migration.

  7. Real time macrophage migration analysis and associated pro-inflammatory cytokine release on transparent carbon nanotube/polymer composite nano-film

    International Nuclear Information System (INIS)

    Khang, Dongwoo

    2015-01-01

    Surface chemistry and nanoscale surface morphology are both influential factors for cell adhesion, growth, and differentiation. In particular, cell migration is one of the major markers of initial immune response activation to implanted biomaterials. Despite their indication, it has been difficult to directly examine macrophages on nanoscale materials, because most nanomaterials possess greater thicknesses than nanoscale. This study developed transparent films comprising a carbon nanotube and polymer composite with controlled surface stiffness and nanoscale roughness. As nanoscale surface topography can incite immune cell activation, analysis of the real-time cell migration (including velocity) of macrophages due to changes in nanoscale surface topography of a biopolymer can support the direct relationship between initial macrophage dynamics and corresponding pro-inflammatory responses. Through real-time analysis, we have identified that surface chemistry and surface nanoscale topography are both independent factors mediating macrophage interactions, and, thus, immune cell behavior can be further controlled by the systematic variation of nanoscale surface topography for a given surface chemistry. Considering that the initial immune response can determine the fate and lifetime of implanted biomaterials, this study presents the direct relationship between initial macrophage dynamics and subsequent inflammatory cytokine release on transparent carbon nanotube polymer composites. (paper)

  8. Variabilities of Low-Latitude Migrating and Nonmigrating Tides in GPS-TEC and TIMED-SABER Temperature During the Sudden Stratospheric Warming Event of 2013

    Science.gov (United States)

    Sridharan, S.

    2017-10-01

    The Global Positioning System deduced total electron content (TEC) data at 15°N (geomagnetic), which is the crest region of equatorial ionization anomaly, are used to study tidal variabilities during the 2013 sudden stratospheric warming (SSW) event. The results from space-time spectral analysis reveal that the amplitudes of migrating diurnal (DW1) and semidiurnal (SW2) tides are larger than those of nonmigrating tides. After the SSW onset, the amplitudes of DW1, SW2, SW1, and DS0 increase. Moreover, they show 16 day variations similar to the periodicity of the high-latitude stratospheric planetary wave (PW), suggesting that the nonmigrating tides (SW1 and DS0) are possibly generated due to nonlinear interaction of migrating tides with PW. Similar spectral analysis on temperature at 10°N obtained from the Sounding of Atmosphere by Broadband Emission Radiometry (SABER) shows that the SW2 enhances at stratospheric heights and the SW2 is more dominant at 80-90 km, but its amplitude decreases around 100 km. The amplitudes of nonmigrating tides become comparable to those of SW2 around 100 km, and their contribution becomes increasingly important at higher heights. This suggests that the nonlinear interaction between migrating tides and PW occurs at low-latitude upper mesospheric heights, as SW2 exhibits 16 day periodicity in SABER temperature at 100 km as observed in TEC. Besides, it is observed that the eastward propagating tides are less dominant than westward propagating tides in both TEC and SABER temperatures.

  9. Fish Species in a Changing World: The Route and Timing of Species Migration between Tropical and Temperate Ecosystems in Eastern Atlantic.

    Directory of Open Access Journals (Sweden)

    Awaluddin Halirin Kaimuddin

    2016-09-01

    Full Text Available The presence of tropical species has been reported in Atlantic-European waters with increasing frequency in recent years. Unfortunately, the history of their migrations is not well understood. In this study, we examined the routes and timing of fish migrations in several ecosystems of the East Atlantic Ocean, combining several publicly available and unpublicized datasets on species occurrences. The species studied were those noted as exotic or rare outside their previous known area of distribution. We used sea surface temperature (SST data obtained from 30 years of satellite observation to define three distinct time periods. Within these periods, temperature trends were studied in six ecosystems: the North Sea, the Celtic Sea, the South European Atlantic Waters, the Mediterranean Sea, the Canary Current and the Guinea Current. We also incorporated bathymetry data to describe the distribution of species. Measurement across a relatively large spatial extent was made possible by incorporating the capabilities of GIS.While SST increased consistently over time in all of the ecosystems observed, the change in number of species differed among ecosystems. The number of species in the middle regions, such as the South European Atlantic Shelf and the Western Mediterranean Sea, tended to increase over time. These regions received numbers of species from the lower or the upper latitudes according to season. Of all of the species observed in the recent period, 7 species from the Canary Current tended to be found in the Western Mediterranean Sea, and 6 species from these two regions extended their distributions to the South European Atlantic Shelf. Twelve species from the Canary Current moved seasonally to the Guinea Current. In the northern regions, 13 species moved seasonally in the North Sea and the Celtic Seas, and 12 of these species reached the South European Atlantic Shelf.This study presents a picture of routes and timing of species migration at the

  10. Timing of changes from a primitive reflex to a voluntary behavior in infancy as a potential predictor of socio-psychological and physical development during juvenile stages among common marmosets

    Directory of Open Access Journals (Sweden)

    Genta Karino

    2015-07-01

    Consequently, we found that both subjects expressed climbing-up behavior in the initial early period, but only the female who developed typically later, switched to jumping-down behavior with pre-facing to ‘down’ direction. Meanwhile, the male who would have developmental delay later, clearly did not show the switching pattern. The results suggest that the switch timing from involuntary to voluntary movement may be a possible predictor of juvenile and adolescent physiological and psychological retardation. The results also suggest that the primate model allows more methods to be developed for early detection of developmental disabilities that could be utilized in humans to pave the way for interventions and possible psychological or psychiatric treatment.

  11. Shear waves in near surface 3D media-SH-wavefield separation, refraction time migration and tomography

    Science.gov (United States)

    Woelz, Susanne; Rabbel, Wolfgang; Mueller, Christof

    2009-05-01

    When investigating topographically irregular layers in the near surface with shear waves, it is of particular importance to consider the 3D-nature of wave propagation. Depending on the layer geometry and on the spatial arrangement of source- and receiver-points significant lateral ray bending can occur causing side-swipe traveltime effects and complicated polarisation patterns. As an example we present a study where 3D-shear wave refraction measurements were applied in order to reconstruct the geometry of a silted ancient harbour basin at the archaeological site of Miletus (West Turkey). Seismic signals were generated with a three-component vector force and recorded with three-component geophones arranged in 2D-arrays of 1 m grid spacing. Since a correct identification of refracted S-wave arrivals is a precondition to traveltime interpretation we investigated a method to decompose these wavefields with respect to their polarisation and azimuth of propagation. Taking advantage of the 2D-geophone arrangement we applied the following processing approach: In case of general lateral heterogeneity a decomposition can be performed by applying the curl and divergence operations to the vector wavefields recorded in 2D-arrays. The separated tangential and normal components to the wavefront in a plane are finally enhanced by combining the different force components in order to eliminate the radiation characteristics of the source. The decomposed wavefield was then the basis for 3D-refractor imaging through a newly formulated map migration of the refracted traveltime field. This technique was developed to map coherent basement structure on the meter-scale. Supplemental tomographic inversion using the refractor topography model as input provided a plausible velocity model, exhibiting characteristic anomalies such as a prominent low velocity zone overlain by a high velocity layer in the refractor. The seismic velocity structure suggests that the harbour basin was locally filled

  12. Processes of the excitation energy migration and transfer in Ce3+-doped alkali gadolinium phosphates studied with time-resolved photoluminescence spectroscopy technique

    International Nuclear Information System (INIS)

    Stryganyuk, G.; Shalapska, T.; Voloshinovskii, A.; Gektin, A.; Krasnikov, A.; Zazubovich, S.

    2011-01-01

    Spectral-kinetic characteristics of Gd 3+ and Ce 3+ luminescence from a series of Ce 3+ -doped alkali gadolinium phosphates of MGdP 4 O 12 type (M=Li, Na, Cs) have been studied within 4.2-300 K temperature range using time-resolved luminescence spectroscopy techniques. The processes of energy migration along the Gd 3+ sub-lattice and energy transfer between the Gd 3+ and Ce 3+ ions have been investigated. Peculiarities of these processes have been compared for MGdP 4 O 12 phosphate hosts with different alkali metal ions. A contribution of different levels from the 6 P j multiplet of the lowest Gd 3+ excited state into the energy migration and transfer processes has been clarified. The phonon-assisted occupation of high-energy 6 P 5/2,3/2 levels by Gd 3+ in the excited 6 P j state has been revealed as a shift of Gd 3+6 P j → 8 S 7/2 emission into the short-wavelength spectral range upon the temperature increase. The relaxation of excited Gd 3+ via phonon-assisted population of Gd 3+6 P 5/2 level (next higher one to the lowest excited 6 P 7/2 ) is supposed to be responsible for the rise in probability of energy migration within the Gd 3+ sub-lattice initiating the Gd 3+ →Ce 3+ energy transfer at T 3+ →Ce 3+ energy transfer at T>150 K is explained by the increase in probability of Gd 3+ relaxation into the highest 6 P 3/2 level of the 6 P j multiplet. An efficient reversed Ce 3+ →Gd 3+ energy transfer has been revealed for the studied phosphates at 4.2 K. - Highlights: →We investigate the Gd 3+ -Ce 3+ energy transfer in alkali gadolinium phosphates. → Thermal population of Gd 3+6 P 5/2 level improves migration along the Gd sub-lattice. → Increasing overlap of Gd 3+ and Ce 3+ states enhances the Gd 3+ -Ce 3+ energy transfer. → In LiGdP 4 O 12 :Ce and NaGdP 4 O 12 :Ce an efficient Ce 3+ -Gd 3+ transfer occurs at 4-300 K. → An effective reverse Gd 3+ -Ce 3+ energy transfer becomes possible at T>150 K.

  13. Migrating Worker

    DEFF Research Database (Denmark)

    Hansen, Hans

    This is the preliminary report on the results obtained in the Migrating Worker-project. This project was initiated by the Danish Ministry of Finance with the aim of illustrating the effects of the 1408/71 agreement and the bilateral double taxation agreements Denmark has with the countries included...

  14. Dateline Migration.

    Science.gov (United States)

    Tomasi, Lydio E., Ed.

    1995-01-01

    Presents data on international migration and its effects in and between various countries in North America, Europe, and Africa. Discussions include refugee, immigrant, and migrant worker flows; the legal, political, and social problems surrounding immigrants; alien terrorism and law enforcement problems; and migrant effects on education, social…

  15. Diversity in destinations, routes and timing of small adult and sub-adult striped bass Morone saxatilis on their southward autumn migration

    Science.gov (United States)

    Mather, Martha E.; Finn, John T.; Pautzke, Sarah M.; Fox, Dewayne A.; Savoy, Tom; Brundage, Harold M.; Deegan, Linda A.; Muth, Robert M.

    2010-01-01

    Almost three-quarters of the 46 young adult and sub-adult striped bass Morone saxatilis that were acoustically tagged in Plum Island Estuary, Massachusetts, U.S.A., in the summer of 2006 were detected in one or more southern coastal arrays during their autumn migration. On the basis of the trajectories along which these M. saxatilis moved from feeding to overwintering areas, three migratory groups emerged. After leaving Plum Island Estuary, about half of the fish were detected only in a mid-latitude array, Long Island Sound. The other half of the tagged fish were detected during autumn and winter in a more southern array, the Delaware Estuary. This latter group of fish may have used two routes. Some travelled to the Delaware Estuary through Long Island Sound while other fish may have taken a second, more direct, coastal route that did not include Long Island Sound. Consequently, a seemingly homogeneous group of fish tagged at the same time in the same non-natal feeding location exhibited a diversity of southward movement patterns that could affect population-level processes. These three groups that differed in overwintering location and migration route could be movement contingents with migratory connectivity.

  16. Modelling population effects of juvenile offshore fish displacement towards adult habitat

    DEFF Research Database (Denmark)

    van de Wolfshaar, K.E.; Tulp, I.; Wennhage, H.

    2015-01-01

    consequences on population dynamics through changes in resource use and competition. To explore this, a conceptual stage-structured model was developed with 3 stages and 2 resources and allowing a move of large juveniles from the shallow to the deep habitat. Large juveniles compete with small juveniles...... in shallow waters and with adults in deeper waters. Alternative stable states occur, with one state dominated by small juvenile biomass and the other dominated by adult biomass. The model results show for both states that while large juvenile biomass responds to a change in time spent in the deep habitat...

  17. Switched Memory B Cells Are Increased in Oligoarticular and Polyarticular Juvenile Idiopathic Arthritis and Their Change Over Time Is Related to Response to Tumor Necrosis Factor Inhibitors.

    Science.gov (United States)

    Marasco, Emiliano; Aquilani, Angela; Cascioli, Simona; Moneta, Gian Marco; Caiello, Ivan; Farroni, Chiara; Giorda, Ezio; D'Oria, Valentina; Marafon, Denise Pires; Magni-Manzoni, Silvia; Carsetti, Rita; De Benedetti, Fabrizio

    2018-04-01

    To investigate whether abnormalities in B cell subsets in patients with juvenile idiopathic arthritis (JIA) correlate with clinical features and response to treatment. A total of 109 patients diagnosed as having oligoarticular JIA or polyarticular JIA were enrolled in the study. B cell subsets in peripheral blood and synovial fluid were analyzed by flow cytometry. Switched memory B cells were significantly increased in patients compared to age-matched healthy controls (P < 0.0001). When patients were divided according to age at onset of JIA, in patients with early-onset disease (presenting before age 6 years) the expansion in switched memory B cells was more pronounced than that in patients with late-onset disease and persisted throughout the disease course. In longitudinal studies, during methotrexate (MTX) treatment, regardless of the presence or absence of active disease, the number of switched memory B cells increased significantly (median change from baseline 36% [interquartile range {IQR} 15, 66]). During treatment with MTX plus tumor necrosis factor inhibitors (TNFi), in patients maintaining disease remission, the increase in switched memory B cells was significantly lower than that in patients who experienced active disease (median change from baseline 4% [IQR -6, 32] versus 41% [IQR 11, 73]; P = 0.004). The yearly rate of increases in switched memory B cells was 1.5% in healthy controls, 1.2% in patients who maintained remission during treatment with MTX plus TNFi, 4.7% in patients who experienced active disease during treatment with MTX plus TNFi, and ~4% in patients treated with MTX alone. Switched memory B cells expand during the disease course at a faster rate in JIA patients than in healthy children. This increase is more evident in patients with early-onset JIA. TNFi treatment inhibits this increase in patients who achieve and maintain remission, but not in those with active disease. © 2018, American College of Rheumatology.

  18. Preventing Juvenile Delinquency

    Directory of Open Access Journals (Sweden)

    Carolina dos Reis

    2016-04-01

    Full Text Available This article aims to problematize discourses about protection and care that have surrounded compulsory hospitalization by evidencing its use as a control and punishment mechanism that increases the social vulnerability of young drug users. For such, we analyze lawsuits involving juveniles who were consigned to psychiatric institutions for drug addiction treatment as a protection measure in the state of Rio Grande do Sul, in Brazil. The analysis of the materials has evidenced discourses that have circumscribed young drug users and constructed this population as potentially dangerous subjects as well as a population category at risk. In this sense, we point out how compulsory hospitalization has emerged out of the lawsuits as a tool for prevention of juvenile delinquency.

  19. Late Onset Juvenile Xanthogranuloma

    Directory of Open Access Journals (Sweden)

    Punithwavathy K

    1999-01-01

    Full Text Available A 19 year old female was seen with multiple skin coloured and hyperpigmented macules, discrete as well as grouped papules and nodules of varying sizes distributed over the face, neck, extensor and flexor aspects of both upper and lower extremities including joints. The trunk was spared. Some of the lesions showed features of spontaneous regression. Investigations confirmed the diagnosis of juvenile xanthogranuloma. Lesions regressed satisfactorily with liquid nitrogen cryotherapy.

  20. Migration of a Real-Time Optimal-Control Algorithm: From MATLAB (Trademark) to Field Programmable Gate Array (FPGA)

    National Research Council Canada - National Science Library

    Moon, II, Ron L

    2005-01-01

    ...) development environment into an FPGA-based embedded-platform development board. Research at the Naval Postgraduate School has produced a revolutionary time-optimal spacecraft control algorithm based upon the Legendre Pseudospectral method...

  1. Impacts of an underwater high voltage DC power cable on fish migration movements in the San Francisco Bay.

    Science.gov (United States)

    Wyman, M. T.; Kavet, R.; Klimley, A. P.

    2016-02-01

    There is an increasingly strong interest on a global scale in offshore renewable energy production and transportation. However, there is concern that the electromagnetic fields (EMF) produced by these underwater cables may alter the behavior and physiology of marine species. Despite this concern, few studies have investigated these effects in free-living species. In 2009, a 85 km long high-voltage DC (HVDC) power cable was placed within the San Francisco Bay, running parallel, then perpendicular to, the migration route of anadromous species moving from the inland river system to the oceans. In this study, we assess the impacts of this HVDC cable on the migration behaviors of EMF-sensitive fish, including juvenile salmonids (Chinook salmon, Oncorhynchus tshawytscha, and steelhead trout, Oncorhynchus mykiss) and adult green sturgeon, Acipenser medirostris. Acoustic telemetry techniques were used to track fish migration movements through the San Francisco Bay both before and after the cable was activated; individuals implanted with acoustic transmitters were detected on cross-channel hydrophone arrays at key locations in the system. Magnetic fields were surveyed and mapped at these locations using a transverse gradiometer, and models of the cable's magnetic field were developed that closely matched the empirically measured values. Here, we present our analyses on the relationships between migration-related behavioral metrics (e.g., percent of successful migrations, duration of migration, time spent near vs. far from cable location, etc.) and environmental parameters, such as cable activation and load level, local magnetic field levels, depth, and currents.

  2. Radium rentention and dosimetry in juvenile beagles

    International Nuclear Information System (INIS)

    Lloyd, R.D.; Jones, C.W.; Bruenger, F.W.; Atherton, D.R.; Mays, C.W.

    1983-01-01

    Retention of administered 226 Ra was substantially greater in beagles injected as 3-month-old juveniles than as 1.4-year-old adults, but the measured 222 Rn/ 226 Ra ratio in bone was significantly less in juveniles for about the first 600 days after injection. An equation that describes the total-body biological retention R in beagles injected with 226 Ra at 3 months of age at any time t (in days) after injection during the first 6.6 years is R = 0.331e/sup -0.206t/ + 0.245e/sup -0.00374t/ + 0.424e/sup -0.000114t/. The rate constant of the final term in the equation for juveniles is similar to that for young adults, suggesting that this component reflects the net turnover rate in the slowly remodeling component of adult bone. Compared to young adult beagles, animals injected as juveniles had a greater fraction of their retained 226 Ra in parts of the skeleton containing much cortical bone, such as paws, and a smaller fraction in those parts containing much trabecular bone

  3. Departure fuel loads in time-minimizing migrating birds can be explained by the energy costs of being heavy

    NARCIS (Netherlands)

    Klaassen, M.R.J.; Lindstrom, A.

    1996-01-01

    Lindstrom & Alerstam (1992 Am. Nat. 140, 477-491) presented a model that predicts optimal departure fuel loads as a function of the rate of fuel deposition in time-minimizing migrants. The basis of the model is that the coverable distance per unit of fuel deposited, diminishes with increasing fuel

  4. A preference for migration

    OpenAIRE

    Stark, Oded

    2007-01-01

    At least to some extent migration behavior is the outcome of a preference for migration. The pattern of migration as an outcome of a preference for migration depends on two key factors: imitation technology and migration feasibility. We show that these factors jointly determine the outcome of a preference for migration and we provide examples that illustrate how the prevalence and transmission of a migration-forming preference yield distinct migration patterns. In particular, the imitation of...

  5. From diversity to conviviality: intra-EU mobility and international migration to Denmark in times of economic recession

    DEFF Research Database (Denmark)

    Duru, Deniz Neriman; Trenz, Hans-Jörg

    2017-01-01

    This article explores differences among EU and non-EU migrants in accommodating to the Danish flexicurity labour and welfare regime during times of economic crisis. We build our findings on a quantitative survey followed by semi-structured qualitative interviews conducted with EU and non-EU migra......This article explores differences among EU and non-EU migrants in accommodating to the Danish flexicurity labour and welfare regime during times of economic crisis. We build our findings on a quantitative survey followed by semi-structured qualitative interviews conducted with EU and non...... to conviviality that is initiated by this group remains however incomplete in light of the unequal opportunities and the differentiated scheme of rights that apply to EU and non-EU immigrants. Danish flexicurity has thus not had the desired inclusive effects but discriminates in terms of facilitating easy access...

  6. Mitigation of artifacts in rtm with migration kernel decomposition

    KAUST Repository

    Zhan, Ge; Schuster, Gerard T.

    2012-01-01

    The migration kernel for reverse-time migration (RTM) can be decomposed into four component kernels using Born scattering and migration theory. Each component kernel has a unique physical interpretation and can be interpreted differently

  7. Dual impacts of climate change: forest migration and turnover through life history

    Science.gov (United States)

    Kai Zhu; Christopher W. Woodall; Souparno Ghosh; Alan E. Gelfand; James S. Clark

    2014-01-01

    Tree species are predicted to track future climate by shifting their geographic distributions, but climate-mediated migrations are not apparent in a recent continental-scale analysis. To better understand the mechanisms of a possible migration lag, we analyzed relative recruitment patterns by comparing juvenile and adult tree abundances in climate space. One would...

  8. Miastenia gravis juvenil Juvenile myasthenia gravis

    Directory of Open Access Journals (Sweden)

    Oscar Papazian

    2009-01-01

    Full Text Available La miastenia gravis juvenil (MGJ es un trastorno crónico auto inmune en el cual existen anticuerpos séricos que al unirse a los receptores de acetilcolin nicotínicos de la membrana muscular de la placa motora alteran la transmisión neuromuscular. El resultado es fatiga muscular precoz con progresión a la parálisis durante estados de contracción muscular iterativos (movimientos o sostenidos (posturas y más raramente parálisis permanente durante el reposo. Los músculos inervados por los nervios craneales, especialmente los extraoculares y elevadores de los párpados, tienen más tendencia a la debilidad muscular persistente que los inervados por otros pares craneales y las extremidades. Las formas clínicas de presentación son generalizadas, oculares y respiratorias. El diagnóstico se sospecha mediante la anamnesia, la fatiga anormal se comprueba mediante el examen físico y la estimulación eléctrica iterativa del nervio que inerva al músculo afectado pero no paralizado. Se corrobora mediante la administración de inhibidores de la acetilcolin esterasa (IACE que al aumentar la cantidad de acetilcolin en la hendidura sináptica, corrigen la fatiga o la debilidad muscular transitoriamente. Se hace el diagnóstico de certeza mediante la demostración sérica de anticuerpos contra los receptores de acetilcolin (ACRA. El tratamiento es a largo plazo sintomático con IACE y etiopatogénico con inmunosupresores, plasmaféresis, gamma globulina endovenosa y timectomía. El curso es crónico. La remisión espontánea o después de tratamiento sintomático o etiopatogénico ocurre entre 1-10 años respectivamente. La mortalidad es prácticamente nula aun durantes las crisis miastenias gracias a la educación de padres, pacientes y público en general sobre el tema, al desarrollo del sistema de respuesta rápida de auxilio domiciliario y las unidades de cuidados intensivos y el empleo de la ventilación asistida profiláctica, plasmaféresis y

  9. Juvenile psittacine environmental enrichment.

    Science.gov (United States)

    Simone-Freilicher, Elisabeth; Rupley, Agnes E

    2015-05-01

    Environmental enrichment is of great import to the emotional, intellectual, and physical development of the juvenile psittacine and their success in the human home environment. Five major types of enrichment include social, occupational, physical, sensory, and nutritional. Occupational enrichment includes exercise and psychological enrichment. Physical enrichment includes the cage and accessories and the external home environment. Sensory enrichment may be visual, auditory, tactile, olfactory, or taste oriented. Nutritional enrichment includes variations in appearance, type, and frequency of diet, and treats, novelty, and foraging. Two phases of the preadult period deserve special enrichment considerations: the development of autonomy and puberty. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Juvenile Dermatomyositis in Pregnancy

    Directory of Open Access Journals (Sweden)

    Anthony Emeka Madu

    2013-01-01

    Full Text Available Juvenile dermatomyositis has variable clinical presentations both in and outside of pregnancy. A literature review indicated that optimal maternal and fetal outcomes can be anticipated when the pregnancy is undertaken while the disease is in remission. Poorer outcomes are associated with flare-up of the disease in early pregnancy compared with exacerbation in the second or third trimester, when fetal prognosis is usually good. We present a case of JDM in pregnancy with disease exacerbation late in pregnancy and review of the relevant literature.

  11. Acoustic reverse-time migration using GPU card and POSIX thread based on the adaptive optimal finite-difference scheme and the hybrid absorbing boundary condition

    Science.gov (United States)

    Cai, Xiaohui; Liu, Yang; Ren, Zhiming

    2018-06-01

    Reverse-time migration (RTM) is a powerful tool for imaging geologically complex structures such as steep-dip and subsalt. However, its implementation is quite computationally expensive. Recently, as a low-cost solution, the graphic processing unit (GPU) was introduced to improve the efficiency of RTM. In the paper, we develop three ameliorative strategies to implement RTM on GPU card. First, given the high accuracy and efficiency of the adaptive optimal finite-difference (FD) method based on least squares (LS) on central processing unit (CPU), we study the optimal LS-based FD method on GPU. Second, we develop the CPU-based hybrid absorbing boundary condition (ABC) to the GPU-based one by addressing two issues of the former when introduced to GPU card: time-consuming and chaotic threads. Third, for large-scale data, the combinatorial strategy for optimal checkpointing and efficient boundary storage is introduced for the trade-off between memory and recomputation. To save the time of communication between host and disk, the portable operating system interface (POSIX) thread is utilized to create the other CPU core at the checkpoints. Applications of the three strategies on GPU with the compute unified device architecture (CUDA) programming language in RTM demonstrate their efficiency and validity.

  12. Flexibility of continental navigation and migration in European mallards

    DEFF Research Database (Denmark)

    van Toor, Mariëlle L.; Hedenström, Anders; Waldenström, Jonas

    2013-01-01

    The ontogeny of continent-wide navigation mechanisms of the individual organism, despite being crucial for the understanding of animal movement and migration, is still poorly understood. Several previous studies, mainly conducted on passerines, indicate that inexperienced, juvenile birds may...... abilities. Here we tested whether immature mallard ducks correct for latitudinal displacement during fall migration within Europe. During two consecutive fall migration periods, we caught immature females on a stopover site in southeast Sweden, and translocated a group of them ca. 1,000 km to southern...... Germany. We followed the movements of the ducks via satellite GPS-tracking and observed their migration decisions during the fall and consecutive spring migration. The control animals released in Ottenby behaved as expected from banding recoveries: they continued migration during the winter and in spring...

  13. Mechanisms influencing the timing and success of reproductive migration in a capital breeding semelparous fish species, the sockeye salmon.

    Science.gov (United States)

    Crossin, Glenn T; Hinch, Scott G; Cooke, Steven J; Cooperman, Michael S; Patterson, David A; Welch, David W; Hanson, Kyle C; Olsson, Ivan; English, Karl K; Farrell, Anthony P

    2009-01-01

    Two populations of homing sockeye salmon (Oncorhynchus nerka; Adams and Chilko) were intercepted in the marine approaches around the northern and southern ends of Vancouver Island (British Columbia, Canada) en route to a natal river. More than 500 salmon were nonlethally biopsied for blood plasma, gill filament tips, and gross somatic energy (GSE) and were released with either acoustic or radio transmitters. At the time of capture, GSE, body length, and circulating testosterone ([T]) differed between populations, differences that reflected known life-history variations. Within-population analyses showed that in Adams sockeye salmon, plasma glucose ([glu]), lactate ([lactate]), and ion concentrations were higher in the northern approach than in the southern approach, suggesting that the former was more stressful. GSE, [T], and gill Na(+),K(+)-ATPase activities also differed between the two locales, and each varied significantly with Julian date, suggesting seasonality. Despite these relative geographic differences, the timing of river entry and the ability to reach spawning areas were strongly correlated with energetic, reproductive, and osmoregulatory state. Salmon that delayed river entry and reached spawning areas had relatively high GSE and low [T] and gill ATPase. In contrast, salmon that entered the river directly but that ultimately failed to reach spawning areas had lower GSE and higher [T] and gill ATPase, and they also swam at significantly faster rates (failed fish approximately 20.0 km d(-1) vs. successful fish approximately 15.5 km d(-1)). Physiologically, salmon that did not enter the river at all but that presumably died in the marine environment exhibited high stress (plasma [glu] and [lactate]) and ionoregulatory measures (plasma [Na(+)], [Cl(-)], osmolality).

  14. Environmental conditions and prey-switching by a seabird predator impact juvenile salmon survival

    Science.gov (United States)

    Wells, Brian K.; Santora, Jarrod A.; Henderson, Mark J.; Warzybok, Pete; Jahncke, Jaime; Bradley, Russell W.; Huff, David D.; Schroeder, Isaac D.; Nelson, Peter; Field, John C.; Ainley, David G.

    2017-01-01

    Due to spatio-temporal variability of lower trophic-level productivity along the California Current Ecosystem (CCE), predators must be capable of switching prey or foraging areas in response to changes in environmental conditions and available forage. The Gulf of the Farallones in central California represents a biodiversity hotspot and contains the largest common murre (Uria aalge) colonies along the CCE. During spring, one of the West Coast's most important Chinook salmon (Oncorhynchus tshawytscha) populations out-migrates into the Gulf of the Farallones. We quantify the effect of predation on juvenile Chinook salmon associated with ecosystem-level variability by integrating long-term time series of environmental conditions (upwelling, river discharge), forage species abundance within central CCE, and population size, at-sea distribution, and diet of the common murre. Our results demonstrate common murres typically forage in the vicinity of their offshore breeding sites, but in years in which their primary prey, pelagic young-of-year rockfish (Sebastesspp.), are less available they forage for adult northern anchovies (Engraulis mordax) nearshore. Incidentally, while foraging inshore, common murre consumption of out-migrating juvenile Chinook salmon, which are collocated with northern anchovy, increases and population survival of the salmon is significantly reduced. Results support earlier findings that show timing and strength of upwelling, and the resultant forage fish assemblage, is related to Chinook salmon recruitment variability in the CCE, but we extend those results by demonstrating the significance of top-down impacts associated with these bottom-up dynamics. Our results demonstrate the complexity of ecosystem interactions and impacts between higher trophic-level predators and their prey, complexities necessary to quantify in order to parameterize ecosystem models and evaluate likely outcomes of ecosystem management options.

  15. Environmental conditions and prey-switching by a seabird predator impact juvenile salmon survival

    Science.gov (United States)

    Wells, Brian K.; Santora, Jarrod A.; Henderson, Mark J.; Warzybok, Pete; Jahncke, Jaime; Bradley, Russell W.; Huff, David D.; Schroeder, Isaac D.; Nelson, Peter; Field, John C.; Ainley, David G.

    2017-10-01

    Due to spatio-temporal variability of lower trophic-level productivity along the California Current Ecosystem (CCE), predators must be capable of switching prey or foraging areas in response to changes in environmental conditions and available forage. The Gulf of the Farallones in central California represents a biodiversity hotspot and contains the largest common murre (Uria aalge) colonies along the CCE. During spring, one of the West Coast's most important Chinook salmon (Oncorhynchus tshawytscha) populations out-migrates into the Gulf of the Farallones. We quantify the effect of predation on juvenile Chinook salmon associated with ecosystem-level variability by integrating long-term time series of environmental conditions (upwelling, river discharge), forage species abundance within central CCE, and population size, at-sea distribution, and diet of the common murre. Our results demonstrate common murres typically forage in the vicinity of their offshore breeding sites, but in years in which their primary prey, pelagic young-of-year rockfish (Sebastes spp.), are less available they forage for adult northern anchovies (Engraulis mordax) nearshore. Incidentally, while foraging inshore, common murre consumption of out-migrating juvenile Chinook salmon, which are collocated with northern anchovy, increases and population survival of the salmon is significantly reduced. Results support earlier findings that show timing and strength of upwelling, and the resultant forage fish assemblage, is related to Chinook salmon recruitment variability in the CCE, but we extend those results by demonstrating the significance of top-down impacts associated with these bottom-up dynamics. Our results demonstrate the complexity of ecosystem interactions and impacts between higher trophic-level predators and their prey, complexities necessary to quantify in order to parameterize ecosystem models and evaluate likely outcomes of ecosystem management options.

  16. Dispersal and migration

    Directory of Open Access Journals (Sweden)

    Schwarz, C.

    2004-06-01

    philopatric movement of geese using a classic multi–state design. Previous studies of philopaty often rely upon simple return rates —however, good mark–recapture studies do not need to assume equal detection probabilities in space and time. This is likely the most important contribution of multi–state modelling to the study of movement. As with many of these studies, the most pressing problem in the analysis is the explosion in the number of parameters and the need to choose parsimonious modelss to get good precision. Drake and Alisauska demonstrate that model choice still remains an art with a great deal of biological insight being very helpful in the task. There is still plenty of scope for novel methods to study migration. Traditionally, there has been a clear cut distinction between birds being labelled as “migrant” or “resident” on the basis of field observations and qualitative interpretations of patterns of ring–recoveries. However, there are intermediate species where only part of the population migrates (partial migrants or where different components of the population migrate to different extents (differential migrants. Siriwardena, Wernham and Baillie (Siriwardena et al., 2004 develop a novel method that produces a quantitative index of migratory tendency. The method uses distributions of ringing–to–recovery distances to classify individual species’ patterns of movement relative to those of other species. The areas between species’ cumulative distance distributions are used with multi–dimensional scaling to produce a similarity map among species. This map can be used to investigate the factors that affect the migratory strategies that species adopt, such as body size, territoriality and distribution, and in studies of their consequences for demographic parameters such as annual survival and the timing of breeding. The key assumption of the method is the similar recovery effort of species over space and time. It would be interesting to

  17. Dispersal and survival of stocked juvenile hatchery-reared Atlantic sturgeon (Acipenser oxyrinchus

    Directory of Open Access Journals (Sweden)

    Kapusta Andrzej

    2016-12-01

    Full Text Available The post-stocking dispersal of juvenile Atlantic sturgeon (Acipenser oxyrinchus Mitchill in the Wis3oka River (southern Poland was investigated using biotelemetry. Thirty-five hatchery-reared juvenile A. oxyrinchus were tagged with radio or acoustic transmitters and tracked using mobile surveys and fixed receivers. Daily movement patterns were similar in 2009 and 2010. The sturgeon migrated with a mean speed of 1.42 km h-1 in 2009 and of 2.06 km h-1 in 2010. Migration rate was not regarded as being dependent on juvenile sturgeon size. The confirmed survival of individuals from the two field seasons differed slightly over the course of this study. Short-term survival of A. oxyrinchus was 86.7 and 90% in 2009 and 2010, respectively.

  18. Juvenile hyperthyroidism: an experience.

    Science.gov (United States)

    Bhadada, S; Bhansali, A; Velayutham, P; Masoodi, S R

    2006-04-01

    To analyze the clinical profile of juvenile hyperthyroidism at presentation, their treatment outcome; predictors of remission and relapse. Retrospective analysis of medical records of 56 patients with juvenile hyperthyroidism seen over a period of 16 years. A cohort of 38 females and 18 males with mean (+/-SD) age of 14.9 +/- 3.4 years (range 3 to 18 years) was analyzed. Majority of patients was in the age group of 12-16 years. Common symptoms observed at presentation were weight loss (82.1%), excessive sweating (78.6%), heat intolerance (76.8%), increased appetite (73.2%) and diarrhea in 48.2%. In addition, accelerated linear growth was observed in 7.1% of patients. Goiter was present in 98.2% of children; 94.5% of which was diffuse and 4.8% was multinodular. The mean ((+/-SD) T3 was 4.8 +/- 3.4 ng/mL (N, 0.6-1.6), T4 was 218 +/- 98 ng/mL (N, 60-155) and TSH was 0.44 +/- 0.36 (N, 0.5-5.5 microIU/mL). TMA positivity seen in 36.9% of patients. All patients were treated with carbimazole; subsequently 4 patients required thyroidectomy and one required radioactive iodine ablation. Mean (+/-SD) duration of follow-up in our patients was 4.9 +/- 3 years, ranging between 1.6 to 16 years and mean (+/-SD) duration of treatment was 34.4 +/- 22.6 months (range 12 to 120 months). Mean (+/-SD) duration to achieve euthyroidism was 5.2 +/- 4.7 months, ranging between 1-33 months. On intention to treat analysis, remission with carbimazole was achieved in 47.6%, remaining patients failed to achieve remission with drug treatment. Graves disease is the commonest cause of juvenile hyperthyroidism. Carbimazole is safe, effective, cheap, and easily available form of therapy. It is occasionally associated with serious side effects but requires prolonged follow up.

  19. Measurements and Calculations of the Slowing-Down and Migration Time; Mesures et Calcul du Temps de Ralentissement et de Migration; Izmereniya i raschety vremeni zamedleniya i migratsii; Medicion y Calculo del Tiempo de Moderacion y de Migracion

    Energy Technology Data Exchange (ETDEWEB)

    Profio, A. E.; Koppel, J. U. [General Atomic Division of General Dynamics Corporation, John Jay Hopkins Laboratory for Pure and Applied Science, San Diego, CA (United States); Adamantiades, A. [Massachusetts Institute of Technology, Cambridge, MA (United States)

    1965-08-15

    The mean time and variance in time for neutrons from an impulse source to slow down and migrate to the energy, angle and position of observation are important quantities in many experiments. The mean time is a correction in time-of-flight measurements of neutron spectra in bulk media, and the variance limits the ultimate resolution of such experiments. These parameters are equally significant in detectors which depend on moderation, in time-of-flight experiments where low energy neutrons are provided by a moderator placed near the pulsed source, and in slowing-down-time spectrometry. Various analytical and numerical methods have been developed to calculate the space-energy-angle-time . dependence, or integrals thereof. It is shown that the time moments, Empty-Set {sup (n)} (r, {Omega}, v, t) = {integral}{sub 0}{sup {infinity}}t{sup n} Empty-Set (r, {Omega}, v, t)dt, can be calculated by repeated application of a steady state transport code. The source term for the calculation of the n{sup -tb} moment is equal to nv{sup -1} Empty-Set {sup (n-1)}. Results are presented for multiplying and non-multiplying mockups of the TRIGA reactor. Another powerful calculational method is the time-dependent Monte Carlo code. Results of a calculation of leakage flux from a thin lead slab are presented. Measurements have been made of the slowing-down time to the cadmium edge and to the 1.46-eV resonance of indium in water and in toluene. Capture gamma rays are detected by a scintillation counter. The technique requires a fairly intense source and efficient detector because of the low duty cycle (short burst width for resolution of the slowing-down time, large interpulse period for thermal neutron die-away) and the small probability for capture. (author) [French] Dans le phenomene de ralentissement et de migration des neutrons puises, amenes a l'enetgie, a l'angle et S la position d'observation, le temps moyen et la variance en temps sont des grandeurs importantes pour beaucoup d

  20. Bacteriological study of juvenile periodontitis in China.

    Science.gov (United States)

    Han, N M; Xiao, X R; Zhang, L S; Ri, X Q; Zhang, J Z; Tong, Y H; Yang, M R; Xiao, Z R

    1991-09-01

    The predominant cultivable bacteria associated with juvenile periodontitis (JP) in China were studied for the first time. Subgingival plaque samples were taken on paper points from 23 diseased sites in 15 JP patients and from 7 healthy sites in 7 control subjects. Serially diluted plaque samples were plated on nonselective blood agar and on MGB agar, a selective medium for the isolation of Actinobacillus actinomycetemcomitans. Fifteen or more isolated colonies from each sample (in sequence without selection) were purified for identification. The results indicated that the microflora in healthy sulci of the 7 control subjects was significantly different from that in diseased sites of JP patients. The predominant species in healthy sulci were Streptococcus spp. and Capnocytophaga gingivalis. In JP patients, Eubacterium sp. was found in significantly higher frequency and proportion. Actinobacillus actinomycetemcomitans was not detected in any samples. It appears that this species is not associated with juvenile periodontitis in China.

  1. Recurrent giant juvenile fibroadenoma

    Directory of Open Access Journals (Sweden)

    Kathryn S. King

    2017-11-01

    Full Text Available Breast masses in children, though rare, present a difficult clinical challenge as they can represent a wide variety of entities from benign fibroadenomas to phyllodes tumors. Rapidly growing or recurrent masses can be particularly concerning to patients, families and physicians alike. Clinical examination and conventional imaging modalities are not efficacious in distinguishing between different tumor types and surgical excision is often recommended for both final diagnosis and for treatment of large or rapidly growing masses. While surgical excision can result in significant long-term deformity of the breast there are some surgical techniques that can be used to limit deformity and/or aid in future reconstruction. Here we present a case of recurrent giant juvenile fibroadenoma with a review of the clinical presentation, diagnostic tools and treatment options.

  2. Fetal and juvenile radiotoxicity

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    A number of studies conducted under this project have demonstrated that many of the biological parameters used to calculate permissible levels of exposure of adults to radioactive materials are inappropriate for the rapidly growing infant or child or for the pregnant female. These include age-related differences in radionuclide deposition, distribution, and retention and associated differences in microdosimetry, as well as the greater intrinsic radiosensitivity of the immature organism. These findings emphasize the need for more detailed information on the metabolism and toxicity of radionuclides in the prenatal and juvenile mammal. The continuing objective of this project is to obtain such information, which is needed to establish appropriate exposure limits for radionuclides of greatest potential hazard to these age groups

  3. Mitigation of artifacts in rtm with migration kernel decomposition

    KAUST Repository

    Zhan, Ge

    2012-01-01

    The migration kernel for reverse-time migration (RTM) can be decomposed into four component kernels using Born scattering and migration theory. Each component kernel has a unique physical interpretation and can be interpreted differently. In this paper, we present a generalized diffraction-stack migration approach for reducing RTM artifacts via decomposition of migration kernel. The decomposition leads to an improved understanding of migration artifacts and, therefore, presents us with opportunities for improving the quality of RTM images.

  4. Juvenile delinquency and correctional treatment in Britain

    OpenAIRE

    堀尾, 良弘; ホリオ, ヨシヒロ; Yoshihiro, Horio

    2006-01-01

    Japanese modernistic culture is influenced not a little from Britain. In looking at the Juvenile Law and the history of correctional treatment in Britain, understanding of today's juvenile delinquency and treatment deepen. Moreover, the background and issue of juvenile delinquency in Britain are also discussed. As a feature of the juvenile delinquency in Britain, the common field with Japan and the field peculiar to Britain became clear in each. It is common to the world that the juvenile del...

  5. The effect of pressurized magma chamber growth on melt migration and pre-caldera vent locations through time at Mount Mazama, Crater Lake, Oregon

    Science.gov (United States)

    Karlstrom, Leif; Wright, Heather M.; Bacon, Charles R.

    2015-01-01

    The pattern of eruptions at long-lived volcanic centers provides a window into the co-evolution of crustal magma transport, tectonic stresses, and unsteady magma generation at depth. Mount Mazama in the Oregon Cascades has seen variable activity over the last 400 ky, including the 50 km3 climactic eruption at ca. 7.7 ka that produced Crater Lake caldera. The physical mechanisms responsible for the assembly of silicic magma reservoirs that are the precursors to caldera-forming eruptions are poorly understood. Here we argue that the spatial and temporal distribution of geographically clustered volcanic vents near Mazama reflects the development of a centralized magma chamber that fed the climactic eruption. Time-averaged eruption rates at Mount Mazama imply an order of magnitude increase in deep magma influx prior to the caldera-forming event, suggesting that unsteady mantle melting triggered a chamber growth episode that culminated in caldera formation. We model magma chamber–dike interactions over ∼50 ky preceding the climactic eruption to fit the observed distribution of surface eruptive vents in space and time, as well as petrologically estimated deep influx rates. Best fitting models predict an expanding zone of dike capture caused by a growing, oblate spheroidal magma chamber with 10–30 MPa of overpressure. This growing zone of chamber influence causes closest approaching regional mafic vent locations as well as more compositionally evolved Mazama eruptions to migrate away from the climactic eruptive center, returning as observed to the center after the chamber drains during the caldera-forming eruption.

  6. Group Work with Juvenile Delinquents.

    Science.gov (United States)

    Zimpfer, David G.

    1992-01-01

    Reviews group work literature on juvenile delinquents. Presents overview of interventions, including positive peer culture, cognitive-behavioral treatment, psychoeducational treatment, treatment of learned behavior, action-oriented treatment, milieu therapy, parental involvement, assertiveness training, and music therapy. Discusses outcome…

  7. Juvenile Angiofibroma: Evolution of Management

    Science.gov (United States)

    Nicolai, Piero; Schreiber, Alberto; Bolzoni Villaret, Andrea

    2012-01-01

    Juvenile angiofibroma is a rare benign lesion originating from the pterygopalatine fossa with distinctive epidemiologic features and growth patterns. The typical patient is an adolescent male with a clinical history of recurrent epistaxis and nasal obstruction. Although the use of nonsurgical therapies is described in the literature, surgery is currently considered the ideal treatment for juvenile angiofibroma. Refinement in preoperative embolization has provided significant reduction of complications and intraoperative bleeding with minimal risk of residual disease. During the last decade, an endoscopic technique has been extensively adopted as a valid alternative to external approaches in the management of small-intermediate size juvenile angiofibromas. Herein, we review the evolution in the management of juvenile angiofibroma with particular reference to recent advances in diagnosis and treatment. PMID:22164185

  8. Juvenile Angiofibroma: Evolution of Management

    Directory of Open Access Journals (Sweden)

    Piero Nicolai

    2012-01-01

    Full Text Available Juvenile angiofibroma is a rare benign lesion originating from the pterygopalatine fossa with distinctive epidemiologic features and growth patterns. The typical patient is an adolescent male with a clinical history of recurrent epistaxis and nasal obstruction. Although the use of nonsurgical therapies is described in the literature, surgery is currently considered the ideal treatment for juvenile angiofibroma. Refinement in preoperative embolization has provided significant reduction of complications and intraoperative bleeding with minimal risk of residual disease. During the last decade, an endoscopic technique has been extensively adopted as a valid alternative to external approaches in the management of small-intermediate size juvenile angiofibromas. Herein, we review the evolution in the management of juvenile angiofibroma with particular reference to recent advances in diagnosis and treatment.

  9. Bilateral, independent juvenile nasopharyngeal angiofibroma

    DEFF Research Database (Denmark)

    Mørkenborg, Marie-Louise; Frendø, M; Stavngaard, T

    2015-01-01

    BACKGROUND: Juvenile nasopharyngeal angiofibroma is a benign, vascular tumour that primarily occurs in adolescent males. Despite its benign nature, aggressive growth patterns can cause potential life-threatening complications. Juvenile nasopharyngeal angiofibroma is normally unilateral, originating...... from the sphenopalatine artery, but bilateral symptoms can occur if a large tumour extends to the contralateral side of the nasopharynx. This paper presents the first reported case of true bilateral extensive juvenile nasopharyngeal angiofibroma involving clinically challenging pre-surgical planning...... embolisation. Radical removal performed as one-step, computer-assisted functional endoscopic sinus surgery was performed. The follow-up period was uncomplicated. CONCLUSION: This case illustrates the importance of suspecting bilateral juvenile nasopharyngeal angiofibroma in patients presenting with bilateral...

  10. A Giant Juvenile Nasopharyngeal Angiofibroma

    Science.gov (United States)

    Yüce, Salim; Uysal, İsmail Önder; Doğan, Mansur; Polat, Kerem; Şalk, İsmail; Müderris, Suphi

    2012-01-01

    Juvenile nasopharyngeal angiofibroma (JNA) are locally growing highly vascular tumours. They are treated primarily by surgical excision ranging from open approach to endoscopic approach. We presented a 20-year-old male with a giant nasopharyngeal juvenile angiofibroma obliterating the pterygopalatine fossa bilaterally, invasing the sphenoid bone and extending to the left nasal passage. His complaints were epistaxis and nasal obstruction. After embolization, the patient was treated surgically with endoscopic approach and discharged as cured without any complication. PMID:23714961

  11. The Globalisation of migration

    OpenAIRE

    Milan Mesić

    2002-01-01

    The paper demonstrates that contemporary international migration is a constitutive part of the globalisation process. After defining the concepts of globalisation and the globalisation of migration, the author discusses six key themes, linking globalisation and international migration (“global cities”, the scale of migration; diversification of migration flows; globalisation of science and education; international migration and citizenship; emigrant communities and new identities). First, in ...

  12. Estimated loss of juvenile salmonids to predation by northern squawfish, walleyes, and smallmouth bass in John Day Reservoir, Columbia River

    International Nuclear Information System (INIS)

    Rieman, B.E.; Beamesderfer, R.C.; Vigg, S.; Poe, T.P.

    1991-01-01

    The authors estimated the loss of juvenile salmonids Oncorhynchus spp. to predation by northern squawfish Ptychocheilus oregonensis, walleyes Stizostedion vitreum, and smallmouth bass Micropterus dolomieu in John Day Reservoir during 1983-1986. Their estimates were based on measures of daily prey consumption, predator numbers, and numbers of juvenile salmonids entering the reservoir during the April-August period of migration. They estimated the mean annual loss was 2.7 million juvenile salmonids. Northern squawfish were responsible for 78% of the total loss; walleyes accounted for 13% and smallmouth bass for 9%. Twenty-one percent of the loss occurred in a small area immediately below McNary Dam at the head of John Day Reservoir. The authors estimated that the three predator species consumed 14% of all juvenile salmonids that entered the reservoir. Mortality changed by month and increased late in the migration season. Monthly mortality estimates ranged from 7% in June and 61% in August. Mortality from predation was highest for chinook salmon O. tshawytscha, which migrated in July and August. Despite uncertainties in the estimates, it is clear that predation by resident fish predators can easily account for previously explained mortality of out-migrating juvenile salmonids. Alteration of the Columbia River by dams and a decline in the number of salmonids could have increased the fraction of mortality caused by predation over what is was in the past

  13. Radioangiography in diagnosis of juvenile angiofibroma

    International Nuclear Information System (INIS)

    Kalantarov, K.D.; Anyutin, R.G.; Ashikhmina, I.G.

    1979-01-01

    To study the blood supply of juvenile angiofibroma of the nasopharynx 10 patients were examined (2 of them were examined twice). Four patients with the deseases of the nose and the nasopharynx of a nonvascular nature were in the control group. The authors used sup(99m)Tc for radioangiography. The investigations were made on the gamma-chamber ''Nuclear-Chicago'' connected to the computer ''Cina-200''. Ten patients with juvenile angiofibroma of the nasopharynx showed rapid accumulation of the radioactive substance at the site of the tumour exceeding its concentration in the carotic arteries by 4-10 times. In unilateral localization of angiofibroma, its blood supply was provided mainly through the external carotic artery at the affection site or evenly through the both external carotic arteries. The data on dynamic distribution of the radioactive substance, scintiphotograms and clinical observations allow a distinct differentiation between juvenile angiofibroma of the nasopharynx the adenoid tissue or any other tumour to determine the angiofibroma size as well as to follow the results of surgical and radiation treatment

  14. Computed tomography of juvenile nasopharyngeal angiofibroma

    Energy Technology Data Exchange (ETDEWEB)

    Park, Cheong Hee; Yoo, Shi Joon; Lee, Yul; Chang, Kee Hyun; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1985-02-15

    It is well known that computed tomography (CT) is useful in detecting accurately the location, extent, erosion and relationship of angiofibroma to surrounding structures such as pterygopalation fossa. It is well known that computed tomography (CT) is useful in detecting accurately the location, sphenoid sinus, and etc. CT of 20 patients with juvenile angiofibroma, which were examined for 5 yeas from February, 1979 to May, 1984 at Department of Radiology, Seoul National University Hospital, were retrospectively analyzed. The results were as follows: 1. All 20 patients of juvenile angiofibroma had tumors in nasopharynx and posterior nasal cavity showing homogeneously dense-enhancing soft tissue mass on CT. There was extension of the tumor from nasopharynx and posterior nasal cavity into paranasal sinus (60%, 12/20), pterygopalatine fossa (55%, 11/20), infratemporal fossa (30%, 6/20), posterior orbit (10%, 2/20) and cranial cavity (15%, 3/20). 2. Angiogrpahy usually adds little diagnostic information, but is still needed to identify the precise source of blood supply to the tumor, and to perform the pre-operative embolization. The use of CT has deferred angiography until just before surgery, permitting embolization at optimal time. 3. CT is almost always necessary to reveal accurately the full extent of the tumor, especially intracranial space in the axial and coronal planes with contrast enhancement. CT is useful both in diagnosis as a guide to angiography and in planning the adequate therapy of juvenile angiofibroma.

  15. The turbulent life of juvenile icebergs: Observations from an array of high-rate time-lapse cameras in LeConte Bay, Alaska

    Science.gov (United States)

    Kienholz, C.; Amundson, J. M.; Jackson, R. H.; Motyka, R. J.; Nash, J. D.; Sutherland, D.

    2017-12-01

    Tidewater glacier behavior is driven by poorly understood processes occurring at the ice-ocean interface, including sedimentation and erosion, iceberg calving, and submarine melting. These processes are inherently difficult to observe, calling for innovative field techniques and numerical models. As part of a multi-year field effort to constrain ocean-glacier heat and mass exchange, we deployed an array of high-rate time-lapse cameras (sampling intervals between 15 seconds and 2 minutes) to monitor the terminus of LeConte Glacier and its proglacial fjord. The camera array has operated continuously for more than a year. Our high sampling rates enable tracking of iceberg motion with optical flow algorithms, which have been used widely in computer vision but less so in glaciology and oceanography. Such algorithms track individual features (e.g., corners of icebergs), which is ideal for iceberg-rich fjords, where motion can vary substantially over short temporal and spatial scales (e.g., due to complex surface currents or different iceberg sizes). We process our data to quantify subdaily to seasonal patterns in surface currents and relate them to forcing from tides, wind, and glacier runoff. Flow is most variable close to the glacier terminus due to frequent calving events and turbulent plume dynamics. Farther down fjord, more consistent patterns emerge, driven by tides, wind, and runoff and altered by fjord geometry. Our tracking results compare favorably to and complement our Acoustic Doppler Current Profiler measurements from boats and moorings. Given their high spatial and temporal resolution, our observations will place important surface constraints on forthcoming hydrodynamic modeling efforts. The deployment of the cameras in a harsh environment and the corresponding image processing provided an opportunity to test hardware and software thoroughly, which will prove useful for similar systems at other glaciers.

  16. MIGRATION IMPACT ON ECONOMICAL SITUATION

    Directory of Open Access Journals (Sweden)

    Virginia COJOCARU

    2016-01-01

    Full Text Available This paper presents recent trends and flows of labor migration and its impact on economic and social life. Main aim of this research sets up the influence of the migration on the European economics and its competitiveness. Methods of research are: method of comparison, analysis method, method of deduction, method of statistics, modeling method. The economic impact of migration has been intensively studied but is still often driven by ill-informed perceptions, which, in turn, can lead to public antagonism towards migration. These negative views risk jeopardising efforts to adapt migration policies to the new economic and demographic challenges facing many countries. Migration Policy looks at the evidence for how immigrants affect the economy in three main areas: The labour market, public purse and economic growth. In Europe, the scope of labour mobility greatly increased within the EU/EFTA zones following the EU enlargements of 2004, 2007 and 2014-2015. This added to labour markets’ adjustment capacity. Recent estimates suggest that as much as a quarter of the asymmetric labour market shock – that is occurring at different times and with different intensities across countries – may have been absorbed by migration within a year.

  17. Species composition, timing, and weather correlates of autumn open-water crossings by raptors migrating along the East-Asian Oceanic Flyway

    Science.gov (United States)

    Concepcion, Camille B.; Dumandan, Patricia T.; Silvosa, Medel R.; Bildstein, Keith L.; Katzner, Todd E.

    2017-01-01

    Raptor migration rarely involves long-distance movements across open oceans. One exception occurs along the East-Asian Oceanic Flyway. We collected migration data at two terrestrial hawkwatch sites along this flyway to better understand open-ocean movements along this largely overwater corridor. At the northern end of the Philippines, at Basco on the island of Batan, we recorded 7587 migratory raptors in autumn 2014. Near the southern end of the Philippines, at Cape San Agustin on the island of Mindanao, we recorded 27,399 raptors migrating in autumn 2012. Chinese Sparrowhawks (Accipiter soloensis) were the most common raptors observed, making up approximately 89% and 92% of total records for Basco and Cape San Agustin, respectively. The Grey-faced Buzzard (Butastur indicus) was the second most common raptor migrant, accounting for 8% of the total counts at both watch sites. The migration period was about 1–2 wk earlier at Basco, the more northerly site, than at Cape San Agustin. Overwater flights at Basco peaked in both the morning and late afternoon, whereas at Cape San Agustin there was only a morning peak. In general, the rate of migration passage at both sites was highest with clear skies when winds were blowing from the northwest. However, we observed interspecific differences in migration behavior at both sites, with Accipiters more likely to be observed with tailwinds and eastward winds, and Grey-faced Buzzards more likely observed with headwinds. These results help to characterize poorly known aspects of raptor biology and to identify potential migratory bottlenecks or key sites for raptor conservation in little-studied Philippine tropical ecosystems.

  18. Fetal and juvenile radiotoxicity

    International Nuclear Information System (INIS)

    Sikov, M.R.

    1985-01-01

    This project is directed at obtaining detailed comparative information on the deposition, distribution, retention, and toxicity of radionuclides in the prenatal and juvenile mammal. Because quantitative data cannot necessarily be extrapolated to man, emphasis is also directed toward establishing patterns, phenomenologic interactions, and relationships which will be useful in determining appropriate exposure levels for rapidly growing infants or children and for pregnant women. Further dosimetry for an experiment to evaluate the effects of foster-rearing of newborn rats on the lifetime effects of 239 Pu exposure has demonstrated that most of the lifetime burden is derived from prenatal exposure and that milk contributes little in addition. Other measurements have confirmed a tentative observation that the lifetime burden in offspring is greater with near-term exposure than with exposure earlier in gestation. Additional results from a comparison of the embryotoxicity of 239 Pu and 241 Am have confirmed that, on the basis of dose administered to the dam, the former has a greater effect on the conceptus. Pilot studies indicate that 233 U is teratogenic, acting as a chemical rather than as a radiological teratogen. Studies with 239 Pu-exposed pregnant rabbits have shown that maternal distribution differs from that in rodents; concentration patterns in the placenta and membranes also differed. 4 figures, 1 table

  19. [Localized eruptive juvenile xanthogranuloma].

    Science.gov (United States)

    Vanotti, S; Chiaverini, C; Rostain, G; Cardot-Leccia, N; Lacour, J-P

    2014-03-01

    Juvenile xanthogranuloma (JXG) is a non-Langerhans histiocytosis of young children characterized by solitary or multiple yellowish cutaneous nodules. Atypical skin lesions such as lichenoid eruptions, and pedunculated, maculopapular, plaque-like or linear lesions have been described. We report a case of eruptive XGJ en plaque in the left leg in an infant. A 13-month-old child presented asymptomatic eruptive, yellowish papules of the leg measuring 5 to 10mm since the age of 2months. There was no cutaneous infiltration between the lesions. Darier's sign was negative. Histological examination confirmed the diagnosis of JXG. The course of the disease comprised a gradual decrease in the number of active lesions with slight residual pigmentation. Our case was suggestive of JXG en plaque. Only 7 cases have been reported in the literature, all appearing before the age of 5months. The lesions corresponded mostly to an asymptomatic erythematous plaque studded with small yellowish/red nodules of variable localisation. Spontaneous involvement was noted in all cases. No systemic involvement was found. Herein we present a unique case of localised multiple JXG without evident clinical infiltrating plaque progressing with self-resolving flares. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  20. JUVENILE RHEUMATOID ARTHRITIS

    Directory of Open Access Journals (Sweden)

    I N Sartika

    2012-11-01

    Full Text Available Juvenile rheumatoid arthritis (JRA is the most common rheumatic condition in children. JRA is defined as persistent arthritis in 1 or more joints for at least 6 weeks, with the onset before age 16 years. The etiology of JRA is unknown. Antigen activated CD4+ T cell stimulate monocytes, macrophages, and synovial fibroblasts to produce the cytokines Interleukin-1 (IL-1, IL-6, and tumor necrosis factor ? (TNF-? and to secrete matrix metalloproteinases, which lead to chronic inflammation due to infiltration of inflammatory cell, angiogenesis, destruction of cartilage and bone with pannus formation. The 3 major subtypes of JRA are based on the symptoms at disease onset and are designated systemic onset, pauciarticular onset, and polyarticular onset. For all patients, the goals of therapy are to decrease chronic joint pain and suppress the inflammatory process. Poor prognostic have been observed in patients with polyarticular onset, rheumatoid factor, persistent morning stiffness, tenosynovitis, involvement of the small joints, rapid appearance of erosions, active late onset childhood, subcutaneous nodules, or antinuclear antibody.

  1. Fetal and juvenile radiotoxicity

    International Nuclear Information System (INIS)

    Sikov, M.R.

    1983-01-01

    Comparative information on the deposition, distribution, retention, and toxicity of radionuclides in the prenatal and juvenile mammal is reported. Emphasis is toward establishing patterns, phenomenologic interactions, and relationships which will be useful in determining appropriate exposure levels for the rapidly growing infant or child and for pregnant women. Recent results have shown that injection of pregnant rats with 239 Pu increases the incidence and severity of adenomatous hyperplasia of the liver in the offspring; the magnitude of these effects is relatd to dose and prenatal age at exposure. Analysis of combined data from several experiments leads to the conclusion that perinatal rats are more sensitive to bone tumor induction by 239 Pu alpha-particle irradiation than are adults. Further histopathologic evaluations of material from earlier experiments have demonstrated that most of the increased incidence of thyroid tumors following 131 I exposure is attributable to follicular tumors. An analysis of the literature led to the conclusion that prenatal irradiation can lead to an increased or decreased incidence of tumors, depending on the specific details of the experimental design and system

  2. Fetal and juvenile radiotoxicity

    International Nuclear Information System (INIS)

    Sikov, M.R.

    1984-01-01

    This project is directed at obtaining detailed comparative information on the deposition, distribution, retention, and toxicity of radionuclides in the prenatal and juvenile mammal. Because quantitative data cannot necessarily be extrapolated to man, emphasis is also directed toward establishing patterns, phenomenologic interactions, and relationships which will be useful in determining appropriate exposure levels for the rapidly growing infant or child and for pregnant women. An experiment to evaluate the effects of foster-rearing of newborn rats on the lifetime effects of 239 Pu exposure has demonstrated that, while longevity is primarily dependent on radiation history, growth rate and adult body weight are related to the exposure and fitness of the foster dam. Results from an ongoing comparison of the dosimetry and embryotoxicity of 239 Pu and 241 Am confirm that the former has a greater effect on the conceptus, on the basis of dose administered to the dam. Studies in the guinea-pig perfusion system have confirmed that maternal blood flow to the placenta is decreased by intravenous doses of 30 nCi/g 239 Pu and suggest that the threshold lies at approximately 5 nCi/g body weight. A dose of 30 nCi/g of 241 Am does not affect blood flow. Clearance of the two actinides is similar when blood flow effects are not considered. 3 figures, 3 tables

  3. [Bacteriological study on juvenile periodontitis].

    Science.gov (United States)

    Han, N

    1991-02-01

    The predominant cultivable microflora of 23 pockets in 15 juvenile periodontitis (JP) patients was studied for the first time in China using the current anaerobic methodology. Samples were taken with sterile paper points and dispersed on a vortex mixer. Then the diluted samples were plated on the non-selective blood agar plates and selective MGB medium which favors the growth of Actinobacillus actimycetemcomitans (Aa) and incubated in anaerobic chamber for 5 days. From each sample 15 or more isolated colonies were picked in sequence without selection and subcultured. The isolates were identified mainly by Schrechenberger's 4 hour rapid methods for biochemical and fermentative tests and the chromatographic analysis of acid end products using ion-chromatography. The results were as follows: 1. The microflora of healthy sulci of 7 healthy young subjects was significantly different from that in the pocket of JP patients. The predominant species in healthy sulci were Streptococcus spp and Capnocytophaga gingivalis. 2. The species increased significantly in JP patients in prevalence and proportions was Eubacterium. Other species in high proportions were Bacteroides oris, B. melaninogenicus, B. gingivalis, Capnocytophaga sputigena, and Actinomyces meyeri, etc. 3. Actinobacillus actinomycetemcomitans was not detected in any of the samples.

  4. Migratory Characteristics of Juvenile Spring Chinook Salmon in the Willamette River : Completion Report 1994.

    Energy Technology Data Exchange (ETDEWEB)

    Schreck, Carl B.; Snelling, J.C.; Ewing, R.E.; Bradford, C.S.; Davis, L.E.; Slater, C.H.

    1994-01-01

    The objective of this research was to examine in detail the migration of juvenile spring chinook salmon (Oncorhynchus tshawytscha) in the Willamette River, Oregon. The authors wanted to determine characteristics of seaward migration of spring chinook smolts in relation to the oxygen supplementation practices at the Oregon Department of Fish and Wildlife (ODFW) Willamette Hatchery and use this information to strengthen the design of the oxygen supplementation project. There is little information available on the effects of oxygen supplementation at hatcheries on the migratory characteristics of juvenile salmon. Such information is required to assess the use of oxygen supplementation as a means of improving hatchery production, its effect on imprinting of juveniles, and finally the return of adults. In the event that oxygen supplementation provides for improved production and survival of juvenile chinook salmon at Willamette Hatchery, background information on the migration characteristics of these fish will be required to effectively utilize the increased production within the goals of the Willamette Fish Management Plan. Furthermore this technology may be instrumental in the goal of doubling the runs of spring Chinook salmon in the Columbia River. While evaluation of success is dependent on evaluation of the return of adults with coded wire tags, examination of the migratory characteristics of hatchery smolts may prove to be equally informative. Through this research it is possible to determine the rate at which individuals from various oxygenation treatment groups leave the Willamette River system, a factor which may be strongly related to adult return rate.

  5. Migratory characteristics of juvenile spring chinook salmon in the Willamette River. Completion report 1994

    International Nuclear Information System (INIS)

    Schreck, C.B.; Snelling, J.C.; Ewing, R.E.; Bradford, C.S.; Davis, L.E.; Slater, C.H.

    1994-01-01

    The objective of this research was to examine in detail the migration of juvenile spring chinook salmon (Oncorhynchus tshawytscha) in the Willamette River, Oregon. The authors wanted to determine characteristics of seaward migration of spring chinook smolts in relation to the oxygen supplementation practices at the Oregon Department of Fish and Wildlife (ODFW) Willamette Hatchery and use this information to strengthen the design of the oxygen supplementation project. There is little information available on the effects of oxygen supplementation at hatcheries on the migratory characteristics of juvenile salmon. Such information is required to assess the use of oxygen supplementation as a means of improving hatchery production, its effect on imprinting of juveniles, and finally the return of adults. In the event that oxygen supplementation provides for improved production and survival of juvenile chinook salmon at Willamette Hatchery, background information on the migration characteristics of these fish will be required to effectively utilize the increased production within the goals of the Willamette Fish Management Plan. Furthermore this technology may be instrumental in the goal of doubling the runs of spring Chinook salmon in the Columbia River. While evaluation of success is dependent on evaluation of the return of adults with coded wire tags, examination of the migratory characteristics of hatchery smolts may prove to be equally informative. Through this research it is possible to determine the rate at which individuals from various oxygenation treatment groups leave the Willamette River system, a factor which may be strongly related to adult return rate

  6. Variability in stream discharge and temperature: a preliminary assessment of the implications for juvenile and spawning Atlantic salmon

    Directory of Open Access Journals (Sweden)

    D. Tetzlaff

    2005-01-01

    Full Text Available This study focuses on understanding the temporal variability in hydrological and thermal conditions in a small mountain stream and its potential implication for two life stages of Atlantic salmon (Salmo salar – stream resident juveniles and returning adult spawners. Stream discharge and temperature in the Girnock Burn, NE Scotland, were characterised over ten hydrological years (1994/1995–2003/2004. Attention was focussed on assessing variations during particular ecologically 'sensitive' time periods when selected life-stages of salmon behaviour may be especially influenced by hydrological and thermal conditions. Empirical discharge data were used to derive hydraulic parameters to predict the Critical Displacement Velocity (CDV of juvenile salmon. This is the velocity above which fish may no longer be able to hold station in the water column and thus can be used as an index of time periods where feeding behaviour might be constrained. In the Girnock Burn, strong inter- and intra-annual variability in hydrological and thermal conditions may have important implications for feeding opportunities for juvenile fish; both during important growth periods in late winter and early spring, and the emergence of fry in the late spring. Time periods when foraging behaviour of juvenile salmon may be constrained by hydraulic conditions were assessed as the percentage time when CDV for 0+ and 1+ fish were exceeded by mean daily stream velocities. Clear seasonal patterns of CDV were apparent, with higher summer values driven by higher stream temperatures and fish length. Inter-annual variability in the time when mean stream velocity exceeded CDV for 0+ fish ranged between 29.3% (1997/1998 and 44.7% (2000/2001. For 1+ fish mean stream velocity exceeded CDV between 14.5% (1997/1998 and 30.7% (2000/2001 of the time. The movement of adult spawners into the Girnock Burn in preparation for autumn spawning (late October to mid-November exhibited a complex

  7. Interntional Migration with Heterogeneous Agents: Theory and Evidence

    DEFF Research Database (Denmark)

    Schröder, Philipp J.H.; Brücker, Herbert

    Two puzzling facts of international migration are that only a small share of a sending country's population emigrates and that net migration rates tend to cease over time. This paper addresses these issues in a migration model with heterogeneous agents that features temporary migration...

  8. Seasonal Juvenile Salmonid Presence and Migratory Behavior in the Lower Columbia River

    Energy Technology Data Exchange (ETDEWEB)

    Carter, Jessica A.; McMichael, Geoffrey A.; Welch, Ian D.; Harnish, Ryan A.; Bellgraph, Brian J.

    2009-04-30

    To facilitate preparing Biological Assessments of proposed channel maintenance projects, the Portland District of the U.S. Army Corps of Engineers contracted the Pacific Northwest National Laboratory to consolidate and synthesize available information about the use of the lower Columbia River and estuary by juvenile anadromous salmonids. The information to be synthesized included existing published documents as well as data from five years (2004-2008) of acoustic telemetry studies conducted in the Columbia River estuary using the Juvenile Salmon Acoustic Telemetry System. For this synthesis, the Columbia River estuary includes the section of the Columbia River from Bonneville Dam at river kilometer (Rkm) 235 downstream to the mouth where it enters the Pacific Ocean. In this report, we summarize the seasonal salmonid presence and migration patterns in the Columbia River estuary based on information from published studies as well as relevant data from acoustic telemetry studies conducted by NOAA Fisheries and the Pacific Northwest National Laboratory (PNNL) between 2004 and 2008. Recent acoustic telemetry studies, conducted using the Juvenile Salmon Acoustic Telemetry System (JSATS; developed by the Portland District of the U.S. Army Corps of Engineers), provided information on the migratory behavior of juvenile steelhead (O. mykiss) and Chinook salmon in the Columbia River from Bonneville Dam to the Pacific Ocean. In this report, Section 2 provides a summary of information from published literature on the seasonal presence and migratory behavior of juvenile salmonids in the Columbia River estuary and plume. Section 3 presents a detailed synthesis of juvenile Chinook salmon and steelhead migratory behavior based on use of the JSATS between 2004 and 2008. Section 4 provides a discussion of the information summarized in the report as well as information drawn from literature reviews on potential effects of channel maintenance activities to juvenile salmonids rearing in

  9. Disease dynamics and bird migration-linking mallards Anas platyrhynchos and subtype diversity of the influenza a virus in time and space

    NARCIS (Netherlands)

    G. Gunnarsson (Gunnar); N. Latorre-Margalef (Neus); K.A. Hobson (Keith); S.L. van Wilgenburg (Steven); J. Elmberg (Johan); B. Olsen (Björn); R.A.M. Fouchier (Ron); J. Waldenström (Jonas)

    2012-01-01

    textabstractThe mallard Anas platyrhynchos is a reservoir species for influenza A virus in the northern hemisphere, with particularly high prevalence rates prior to as well as during its prolonged autumn migration. It has been proposed that the virus is brought from the breeding grounds and

  10. Pre- and post-displacement stressors and time of migration as related to self-rated health among Iraqi immigrants and refugees in Southeast Michigan.

    Science.gov (United States)

    Jamil, Hikmet; Nassar-McMillanb, Sylvia; Lambert, Richard; Wangd, Yun; Ager, Joel; Arnetz, Bengt

    2010-01-01

    The objective of this study was to determine whether perceived health status of Iraqi immigrants and refugees residing in the United States was related to pre-migration environmental stress, current unemployment, and if they had emigrated before or after the 1991 Gulf War. A random sample of Iraqis residing in Southeast Michigan, US, was interviewed using an Arab language structured survey. The main outcome measure was self-rated health (SRH). Major predictors included socioeconomics, employment status, pre-migration environmental stress, and health disorders. Path analysis was used to look at mediating effects between predictors and SRH. We found that SRH was significantly worse among participants that had left Iraq after the 1991 Gulf War. Unemployment and environmental stress exposure were inversely related to SRH. There was a direct path between Gulf War exposure and poor health. In addition, there were indirect paths mediated through psychosomatic and psychiatric disorders to SRH. Another path went from Gulf War exposure, via environmental stress and somatic health to poor health. Unemployment had a direct path, as well as indirect paths mediated through psychiatric and psychosomatic disorders, to poor self-rated health. In conclusion, these results suggest that pre- as well as post-migration factors, and period of migration, affect health.

  11. New developments in juvenile systemic and localized scleroderma.

    Science.gov (United States)

    Foeldvari, Ivan

    2013-11-01

    Juvenile localized scleroderma (jLS) and juvenile systemic sclerosis (jSS) are both orphan diseases, with jLS around 10 times more frequent than jSS. In recent years the time gap between the appearance of symptoms and diagnosis has become significantly shorter. This review focuses on the new classifications of jSS and jLS, and on the developments and adaptations of the outcome measures for certain organ involvements whereby progress has been made regarding pediatric patients. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Many Faces of Migrations

    Directory of Open Access Journals (Sweden)

    Milica Antić Gaber

    2013-12-01

    We believe that in the present thematic issue we have succeeded in capturing an important part of the modern European research dynamic in the field of migration. In addition to well-known scholars in this field several young authors at the beginning their research careers have been shortlisted for the publication. We are glad of their success as it bodes a vibrancy of this research area in the future. At the same time, we were pleased to receive responses to the invitation from representatives of so many disciplines, and that the number of papers received significantly exceeded the maximum volume of the journal. Recognising and understanding of the many faces of migration are important steps towards the comprehensive knowledge needed to successfully meet the challenges of migration issues today and even more so in the future. It is therefore of utmost importance that researchers find ways of transferring their academic knowledge into practice – to all levels of education, the media, the wider public and, of course, the decision makers in local, national and international institutions. The call also applies to all authors in this issue of the journal.

  13. PSYCHOSOCIAL PROFILE OF JUVENILE DIABETES

    Science.gov (United States)

    Dass, Jyoti; Dhavale, H.S.; Rathi, Anup

    1999-01-01

    A study of the complex relationships between the patient characteristics, family and environmental influences, physician's behaviour and the demands of the disease with its management in Juvenile Diabetics was taken up at a general hospital. 90 subjects were selected for the study and grouped into three. Group A consisted of 30 Juvenile Diabetics, Group B of 30 Adult Diabetics and Group C of 30 Normal healthy adolescents. The impact of the illness was measured on the Diabetes Impact Measurement Scale (DIMS), the behavioural deviations and the parental attitudes towards child rearing on the Fallstrom's Questionnaire (FQ) and the family environment on the Family Climate Scale (FCS). Psychiatric morbidity was assessed using DSM-IV criteria. Group A & B were compared on the DIMS and Group A & C on FQ & FCS. Adult diabetics had a greater impact of diabetes. Juvenile diabetics had significantly higher frequency of behavioural deviations as compared to controls. Also there was a higher number of responses on questions indicating an overprotecting attitude amongst parents of juvenile diabetics. There was an increased incidence of psychiatric morbidity in juvenile diabetics as compared to normal adolescents irrespective of the family environment. The results are discussed in relation to current literature. PMID:21430802

  14. Otolith Sr concentration analyzed by PIXE in Ariake estuary-dependent sea bass juveniles

    International Nuclear Information System (INIS)

    Ohta, Taro; Arai, Nobuaki; Tanaka, Masaru; Yoshida, Koji

    1997-01-01

    Japanese sea bass (Lateolabrax japonicus) is a typical euryhaline marine fish and frequently migrates from salt to freshwater environments during early life stages. We hypothesized that strontium concentrations in the otolith could be a useful index to examine freshwater entry because of its lower concentration in freshwater. Otoliths of Japanese sea bass juveniles collected in the Chikugo river and estuary were analyzed by Particle Induced X-ray Emission (PIXE) to see relationship between strontium concentration and ambient salinity. Strontium concentrations in otoliths of sea bass juveniles are significantly lower in the river samples than in brackish water samples. (author)

  15. Juvenile rheumatoid arthritis

    International Nuclear Information System (INIS)

    Naz, S.; Mushtaq, A.; Bari, A.; Maqsud, A.; Khan, M. Z.; Ahmad, T. M.; Saira Rehman

    2013-01-01

    Objective: To determine the spectrum of clinical presentation, laboratory parameters and drug therapy in patients with Juvenile Rheumatoid Arthritis (JRA). Study Design: Case series. Place and Duration of Study: The Children's Hospital and The Institute of Child Health, Lahore, from October 2008 to October 2011. Methodology: All patients who fulfilled the American College of Rheumatology criteria for JRA were enrolled. Their clinical features, investigations done and treatment received for JRA were noted. Statistical analysis of data was done on SPSS version 16.0 for obtaining descriptive statistics. Results: Out of 185 patients, 50.3% (n = 93) were females; 54% (n = 100) were between 10 - 15 years of age. Polyarthritis was found in 71.9% (n = 133) followed by oligoarthritis (22.7%, n = 42) and systemic onset disease (5.4%, n = 10). Morning stiffness (78%) and fever (68%) were the most common clinical presentations. All patients with systemic onset disease had fever (n = 10) followed by skin rash, hepatosplenomegaly and lymphadenopathy. Uveitis was found in 2 patients, and both belonged to the oligoarticular group. Rheumatoid factor was found in 10.27% (n = 19) of all patients. All patients were given non-steroidal anti-inflammatory drugs (NSAIDs). Disease modifying agents (methotrexate) were given to 43.8% (n = 81). Steroids were used in 61% (n = 113) of patients either with NSAIDs alone or NSAIDs plus methotrexate. Conclusion: Disease profile of JRA at the study centre showed that polyarthritis is the commonest type. Recognition of subtypes will help in planning the management of these patients. (author)

  16. Coblation-assisted endonasal endoscopic resection of juvenile nasopharyngeal angiofibroma.

    Science.gov (United States)

    Ye, L; Zhou, X; Li, J; Jin, J

    2011-09-01

    Juvenile nasopharyngeal angiofibroma may be successfully resected using endoscopic techniques. However, the use of coblation technology for such resection has not been described. This study aimed to document cases of Fisch class I juvenile nasopharyngeal angiofibroma with limited nasopharyngeal and nasal cavity extension, which were completely resected using an endoscopic coblation technique. We retrospectively studied 23 patients with juvenile nasopharyngeal angiofibroma who underwent resection with either traditional endoscopic instruments (n = 12) or coblation (n = 11). Intra-operative blood loss and overall operative time were recorded. The mean tumour resection time for coblation and traditional endoscopic instruments was 87 and 136 minutes, respectively (t = 9.962, p angiofibroma (Fisch class I), with good surgical margins and minimal blood loss.

  17. The in vitro anthelmintic effects of plumbagin on newly excysted and 4-weeks-old juvenile parasites of Fasciola gigantica.

    Science.gov (United States)

    Lorsuwannarat, Natcha; Piedrafita, David; Chantree, Pathanin; Sansri, Veerawat; Songkoomkrong, Sineenart; Bantuchai, Sirasate; Sangpairot, Kant; Kueakhai, Pornanan; Changklungmoa, Narin; Chaichanasak, Pannigan; Chansela, Piyachat; Sobhon, Prasert

    2014-01-01

    The effect of plumbagin (PB, 5-hydroxy-2-methyl-1,4-naphthoquinone) against newly excysted juveniles (NEJs) and 4-weeks-old immature parasites of Fasciola gigantica were compared with triclabendazole (TCZ). The anthelmintic efficacy of 1, 10 and 100μg/ml of PB or TCZ following incubation in vitro for 1-24h was compared using a combination of relative motility (RM), survival index (SI) and larval migration inhibition (LMI) assays for parasite viability. The RM and SI values of the PB-treated group decreased at a more rapid rate than the TCZ-treated group. For NEJs, the decreased RM values were first observed at 1h incubation with 1μg/ml PB, and 90% of flukes were killed at 24h. In contrast, in TCZ-treated groups a 10-fold higher concentration of TCZ (10μg/ml) resulted in only 9% dead parasites after 24h incubation. In 4-weeks-old juvenile parasites, PB reduced the RM value at 10μg/ml with 100% of flukes dead after 3h, while TCZ decreased RM values at the concentration of 100μg/ml but with only 5% of flukes killed at 24h. NEJs treated with PB exhibited 88%, 99% and 100% of LMIs at the concentrations of 1, 10 and 100μg/ml, respectively. NEJs incubated with TCZ have an LMI of only 32% at the highest concentration of 100μg/ml. Similarly PB had a significantly greater killing of immature 4weeks juvenile stages than TCZ at all concentrations; however, 4-weeks-old juvenile parasites were more resistant to killing by PB or TCZ at all concentrations when compared to NEJs. Further studies were carried out to investigate the alterations of the parasite tegument by scanning electron microscope (SEM). PB caused similar tegumental alterations in 4-weeks-old juveniles as those observed in TCZ treatment but with greater damage at comparative time points, comprising of swelling, blebbing and rupture of the tegument, loss of spines, and eventual erosion, lesion and desquamation of the total tegument. These data indicate that PB had a greater fasciolicidal effect against

  18. REFORMATIONS IN ZIMBABWE'S JUVENILE JUSTICE SYSTEM

    African Journals Online (AJOL)

    Mugumbate

    1996-05-23

    May 23, 1996 ... The article is based on a desk review of existing literature on juvenile crime in the country. ... that Zimbabwe's juvenile justice system is transforming from being ... recommendations include expanding the Pre-trial Diversion ...

  19. Family migration and employment: the importance of migration history and gender.

    Science.gov (United States)

    Bailey, A J; Cooke, T J

    1998-01-01

    "This article uses event history data to specify a model of employment returns to initial migration, onward migration, and return migration among newly married persons in the U.S. Husbands are more likely to be full-time employed than wives, and being a parent reduces the employment odds among married women. Employment returns to repeated migration differ by gender, with more husbands full-time employed after onward migration and more wives full-time employed after return migration events. We interpret these empirical findings in the context of family migration theory, segmented labor market theory, and gender-based responsibilities." Data are from the National Longitudinal Survey of Youth from 1979 to 1991. excerpt

  20. Juvenile technologies in foreign publications

    Directory of Open Access Journals (Sweden)

    Shpagina E.M.

    2012-09-01

    Full Text Available The article provides the review of foreign publications, concerning the juvenile technologies used in France, Canada, Germany and Switzerland. The paper presents legal, social and psychotherapeutic aspects of juvenile judiciary in foreign countries. The authors paid special attention to the complexity of approaches to young children and teenagers who found themselves in complicated life circumstances or got into trouble with the law. The article gives examples of using the following techniques: cognitive-behavioral intervention, mediation, family therapy (including family background and family history, relations theory, narrative practices, utilization of «emotional intelligence» resources.

  1. Behavior and movement of formerly landlocked juvenile coho salmon after release into the free-flowing Cowlitz River, Washington

    Science.gov (United States)

    Kock, Tobias J.; Henning, Julie A.; Liedtke, Theresa L.; Royer, Ida M.; Ekstrom, Brian K.; Rondorf, Dennis W.

    2011-01-01

    Formerly landlocked Coho Salmon (Oncorhynchus kisutch) juveniles (age 2) were monitored following release into the free-flowing Cowlitz River to determine if they remained in the river or resumed seaward migration. Juvenile Coho Salmon were tagged with a radio transmitter (30 fish) or Floy tag (1050 fish) and their behavior was monitored in the lower Cowlitz River. We found that 97% of the radio-tagged fish remained in the Cowlitz River beyond the juvenile outmigration period, and the number of fish dispersing downstream decreased with increasing distance from the release site. None of the tagged fish returned as spawning adults in the 2 y following release. We suspect that fish in our study failed to migrate because they exceeded a threshold in size, age, or physiological status. Tagged fish in our study primarily remained in the Cowlitz River, thus it is possible that these fish presented challenges to juvenile salmon migrating through the system either directly by predation or indirectly by competition for food or habitat. Given these findings, returning formerly landlocked Coho Salmon juveniles to the free-flowing river apparently provided no benefit to the anadromous population. These findings have management implications in locations where landlocked salmon have the potential to interact with anadromous species of concern.

  2. Psychopathology and personality in juvenile sexual homicide offenders.

    Science.gov (United States)

    Myers, W C; Blashfield, R

    1997-01-01

    This project describes the psychopathology and personality findings in 14 juveniles who committed sexual homicide. These incarcerated youth were assessed using a structured interview, a personality assessment instrument, correctional files review, and an author-designed clinical interview. Nearly all of these youth met DSM-III-R conduct disorder criteria at the time of the crime. The presence of personality disorders and moderately high psychopathy scores at follow-up were common. Two-thirds of these youth reported the presence of violent sexual fantasies before their crimes. Weapons, most often knives, were used by these juvenile sexual murderers to kill known victims in a majority of the cases. They usually acted alone and selected a low risk victim. These findings suggest that juvenile sexual murderers are an emotionally and behaviorally disturbed population with identifiable psychopathology, personality disturbances, and criminal patterns.

  3. The sound of migration: exploring data sonification as a means of interpreting multivariate salmon movement datasets

    Directory of Open Access Journals (Sweden)

    Jens C. Hegg

    2018-02-01

    Full Text Available The migration of Pacific salmon is an important part of functioning freshwater ecosystems, but as populations have decreased and ecological conditions have changed, so have migration patterns. Understanding how the environment, and human impacts, change salmon migration behavior requires observing migration at small temporal and spatial scales across large geographic areas. Studying these detailed fish movements is particularly important for one threatened population of Chinook salmon in the Snake River of Idaho whose juvenile behavior may be rapidly evolving in response to dams and anthropogenic impacts. However, exploring movement data sets of large numbers of salmon can present challenges due to the difficulty of visualizing the multivariate, time-series datasets. Previous research indicates that sonification, representing data using sound, has the potential to enhance exploration of multivariate, time-series datasets. We developed sonifications of individual fish movements using a large dataset of salmon otolith microchemistry from Snake River Fall Chinook salmon. Otoliths, a balance and hearing organ in fish, provide a detailed chemical record of fish movements recorded in the tree-like rings they deposit each day the fish is alive. This data represents a scalable, multivariate dataset of salmon movement ideal for sonification. We tested independent listener responses to validate the effectiveness of the sonification tool and mapping methods. The sonifications were presented in a survey to untrained listeners to identify salmon movements with increasingly more fish, with and without visualizations. Our results showed that untrained listeners were most sensitive to transitions mapped to pitch and timbre. Accuracy results were non-intuitive; in aggregate, respondents clearly identified important transitions, but individual accuracy was low. This aggregate effect has potential implications for the use of sonification in the context of crowd

  4. Juvenile Courts. Creation and development

    Directory of Open Access Journals (Sweden)

    Montserrat GONZÁLEZ FERNÁNDEZ

    2013-11-01

    Full Text Available This paper studies the creation of Juvenile or Children's Courts in Spain, analysing their reasons and aims, as well as the ethical and political connotations present on their way of acting. Their history and the one of the institutions that complement them is built from the legislation, writings and ideas of their promoters.

  5. Juvenile Justice: A Bibliographic Essay.

    Science.gov (United States)

    Kondak, Ann

    1979-01-01

    Provides information on the background and legal framework of the juvenile justice system, the issues that confront it, and the pressures for change, as well as noting some sources of information on the system. Available from American Association of Law Libraries, 53 West Jackson Blvd., Suite 1201, Chicago, Illinois 60604; sc $4.00. (Author/IRT)

  6. [Sex-linked juvenile retinoschisis].

    Science.gov (United States)

    François, P; Turut, P; Soltysik, C; Hache, J C

    1976-02-01

    About 13 observations of sexe linked juvenile retinoschisis, the authors describe the ophthalmoscopic, fluorographic and functional aspects of the disease whose caracteristics are:--its sexe linked recessive heredity; --its clinical characterestics associating: a microcystic macular degeneration, peripheral retinal lesions, vitreous body alterations, --an electroretinogram of the negative type.

  7. Juvenile European anchovy otolith microstructure

    Directory of Open Access Journals (Sweden)

    Pablo Cermeño

    2006-09-01

    Full Text Available Juvenile European anchovy (Engraulis encrasicolus has a complex incremental growth pattern that was studied using scanning electron microscope (SEM and optical microscope observations. Daily increments were identified and related to rhythmic growth patterns while double-band structures were identified as one increment. The causes of these growth patterns are discussed.

  8. CT appearance of juvenile angiofibroma

    Energy Technology Data Exchange (ETDEWEB)

    Ueda, Jun; Hara, Kazuo (Sumitomo Hospital, Osaka (Japan)); Fukuzumi, Akio; Uchida, Hideo

    1983-06-01

    Three verified cases of juvenile angiofibroma were presented. All of them were young and adolescent male CT proved to be an ideal tool in evaluating the extension of this tumor. The appearance on plain CT was multilobulated with displacement of the adjacent bony structures. On enhancement, there was intense staining of the tumor.

  9. What is Justice for Juveniles?

    Science.gov (United States)

    Rothwell, Jennifer Truran

    1997-01-01

    Provides background information and related learning activities for three areas of inquiry involving youth and violence: (1) "Evolution of the Juvenile Justice System"; (2) "The Literature of Crime and Poverty"; (3) "Youth Crime and Public Policy." Includes a list of six recommended Web sites. (MJP)

  10. Statistical indicators and trends in juvenile delinquency in modern Russia

    Directory of Open Access Journals (Sweden)

    Yuzikhanova E.G.

    2014-12-01

    Full Text Available Statistics of juvenile delinquency in Russia for ten years, allowing to determine its current trends, is presented. It’s noted that earlier the proportion of juveniles among all criminals was about 11-12%. During the period from 2003 to 2013 the proportion of juveniles in the total number of identified offenders decreased to 6%. Despite the reduction in the number of crimes committed by this category of persons, for several years the largest criminal activity is maintained in the age group 16-17 years (70%. Smaller proportion is the age group 14-15 years, there’s a reduction in the number of committed crimes: from 49,300 in 2000 to 19,700 in 2013. Over the same period, the number of reported crimes committed by minors or with their complicity decreased almost three times. With all the ambiguity of attitude to the considered problem, the author defines the role of criminal law policy of the state in response to trends in juvenile crime taking into account its specificity, caused by the complex of interrelated factors related to age, social, psychological characteristics of juveniles as a special social group, the originality of their social status. The legislative novel is considered: the punishment in the form of arrest is not imposed on persons under the age of eighteen by the time of court verdict. It’s summarized that the problems of juvenile delinquency are only partly solved by the humanization of criminal law policy of the state in order to restore social justice, correct the convict and prevent new crimes commission.

  11. Terrestrial movements and habitat use of gopher frogs in longleaf pine forests: a comparative study of juveniles and adults

    Science.gov (United States)

    Elizabeth A. Roznik; Steve A. Johnson; Cathryn H. Greenberg; George W. Tanner

    2009-01-01

    Many animals exhibit changes in patterns of movement and habitat use as they age, and understanding such ontogenetic shifts is important for ensuring that habitat management is appropriate for all life stages. We used radiotelemetry to study movements and habitat use of juvenile and adult gopher frogs (Rana capito) as they migrated from the same ponds following...

  12. Assessing survival of Mid-Columbia River released juvenile salmonids at McNary Dam, Washington, 2008-09

    Science.gov (United States)

    Evans, Scott D.; Walker, Christopher E.; Brewer, Scott J.; Adams, Noah S.

    2010-01-01

    little information is available about their survival as they pass hydroelectric dams in the lower Columbia River. Collecting information on fish released in the Mid-Columbia River, as well as on fish released 8 kilometers upstream of McNary Dam, allowed us to evaluate similarities and differences in passage and survival probabilities. In general, juvenile salmonids released in the Mid-Columbia River and detected at and downstream of McNary Dam showed trends in passage and survival probabilities that were similar to fish released 8 kilometers upstream of McNary Dam. This suggests that increased migration time or length of migration had little effect on behavior and survival of Mid-Columbia River released juvenile salmonids detected at McNary Dam.

  13. Father's Labour Migration and Children's School Discontinuation in Rural Mozambique.

    Science.gov (United States)

    Yabiku, Scott T; Agadjanian, Victor

    2017-08-01

    We examine how the discontinuation of schooling among left-behind children is related to multiple dimensions of male labor migration: the accumulation of migration experience, the timing of these migration experiences in the child's life course, and the economic success of the migration. Our setting is rural southern Mozambique, an impoverished area with massive male labor out-migration. Results show that fathers' economically successful labor migration is more beneficial for children's schooling than unsuccessful migration or non-migration. There are large differences, however, by gender: compared to sons of non-migrants, sons of migrant fathers (regardless of migration success) have lower rates of school discontinuation, while daughters of migrant fathers have rates of school discontinuation no different than daughters of non-migrants. Furthermore, accumulated labor migration across the child's life course is beneficial for boys' schooling, but not girls'. Remittances sent in the past year reduce the rate of discontinuation for sons, but not daughters.

  14. MANAGING MIGRATION: TURKISH PERSPECTIVE

    Directory of Open Access Journals (Sweden)

    İhsan GÜLAY

    2018-04-01

    Full Text Available Conducting migration studies is of vital importance to Turkey, a country which has been experiencing migration throughout history due to its “open doors policy”. The objective of this study is to evaluate the strategic management of migration in Turkey in order to deal with the issue of migration. The main focus of the study is Syrian migrants who sought refuge in Turkey due to the civil war that broke out in their country in April 2011. This study demonstrates the policies and processes followed by Turkey for Syrian migration flow in terms of the social acceptance and harmonisation of the migrants within a democratic environment. The study addresses some statistical facts and issues related to Syrian migration as it has become an integral part of daily life in Turkey. The study also reviews how human rights are protected in the migration process. The study will provide insights for developing sound strategic management policies for the migration issue.

  15. Migration and revolution

    Directory of Open Access Journals (Sweden)

    Nando Sigona

    2012-06-01

    Full Text Available The Arab Spring has not radically transformed migration patterns in the Mediterranean, and the label ‘migration crisis’ does not do justice to the composite and stratified reality.

  16. Disease dynamics and bird migration--linking mallards Anas platyrhynchos and subtype diversity of the influenza A virus in time and space.

    Directory of Open Access Journals (Sweden)

    Gunnar Gunnarsson

    Full Text Available The mallard Anas platyrhynchos is a reservoir species for influenza A virus in the northern hemisphere, with particularly high prevalence rates prior to as well as during its prolonged autumn migration. It has been proposed that the virus is brought from the breeding grounds and transmitted to conspecifics during subsequent staging during migration, and so a better understanding of the natal origin of staging ducks is vital to deciphering the dynamics of viral movement pathways. Ottenby is an important stopover site in southeast Sweden almost halfway downstream in the major Northwest European flyway, and is used by millions of waterfowl each year. Here, mallards were captured and sampled for influenza A virus infection, and positive samples were subtyped in order to study possible links to the natal area, which were determined by a novel approach combining banding recovery data and isotopic measurements (δ(2H of feathers grown on breeding grounds. Geographic assignments showed that the core natal areas of studied mallards were in Estonia, southern and central Finland, and northwestern Russia. This study demonstrates a clear temporal succession of latitudes of natal origin during the course of autumn migration. We also demonstrate a corresponding and concomitant shift in virus subtypes. Acknowledging that these two different patterns were based in part upon different data, a likely interpretation worth further testing is that the early arriving birds with more proximate origins have different influenza A subtypes than the more distantly originating late autumn birds. If true, this knowledge would allow novel insight into the origins and transmission of the influenza A virus among migratory hosts previously unavailable through conventional approaches.

  17. An Enriched Environment Promotes Shelter-Seeking Behaviour and Survival of Hatchery-Produced Juvenile European Lobster (Homarus gammarus)

    Science.gov (United States)

    Aspaas, Stian; Grefsrud, Ellen Sofie; Fernö, Anders; Jensen, Knut Helge; Trengereid, Henrik; Agnalt, Ann-Lisbeth

    2016-01-01

    The high loss of newly released hatchery-reared European lobster (Homarus gammarus) juveniles for stock enhancement is believed to be the result of maladaptive anti-predator behaviour connected to deprived stimuli in the hatchery environment. Our objective was to learn if an enriched hatchery environment enhances shelter-seeking behaviour and survival. In the “naïve” treatment, the juveniles were raised in single compartments without substrate and shelter whereas juveniles in the “exposed” treatment experienced substrate, shelter and interactions with conspecifics. Three experiments with increasing complexity were conducted. Few differences in shelter-seeking behaviour were found between treatments when one naïve or one exposed juvenile were observed alone. When observing interactions between one naïve and one exposed juvenile competing for shelter, naïve juveniles more often initiated the first aggressive encounter. The third experiment was set up to simulate a release for stock enhancement. Naïve and exposed juveniles were introduced to a semi-natural environment including substrate, a limited number of shelters and interactions with conspecifics. Shelter occupancy was recorded three times during a period of 35 days. Exposed juveniles occupied more shelters, grew larger and had higher survival compared with naïve juveniles. Our results demonstrate that experience of environmental complexity and social interactions increase shelter-seeking ability and survival in hatchery reared lobster juveniles. PMID:27560932

  18. An Enriched Environment Promotes Shelter-Seeking Behaviour and Survival of Hatchery-Produced Juvenile European Lobster (Homarus gammarus).

    Science.gov (United States)

    Aspaas, Stian; Grefsrud, Ellen Sofie; Fernö, Anders; Jensen, Knut Helge; Trengereid, Henrik; Agnalt, Ann-Lisbeth

    2016-01-01

    The high loss of newly released hatchery-reared European lobster (Homarus gammarus) juveniles for stock enhancement is believed to be the result of maladaptive anti-predator behaviour connected to deprived stimuli in the hatchery environment. Our objective was to learn if an enriched hatchery environment enhances shelter-seeking behaviour and survival. In the "naïve" treatment, the juveniles were raised in single compartments without substrate and shelter whereas juveniles in the "exposed" treatment experienced substrate, shelter and interactions with conspecifics. Three experiments with increasing complexity were conducted. Few differences in shelter-seeking behaviour were found between treatments when one naïve or one exposed juvenile were observed alone. When observing interactions between one naïve and one exposed juvenile competing for shelter, naïve juveniles more often initiated the first aggressive encounter. The third experiment was set up to simulate a release for stock enhancement. Naïve and exposed juveniles were introduced to a semi-natural environment including substrate, a limited number of shelters and interactions with conspecifics. Shelter occupancy was recorded three times during a period of 35 days. Exposed juveniles occupied more shelters, grew larger and had higher survival compared with naïve juveniles. Our results demonstrate that experience of environmental complexity and social interactions increase shelter-seeking ability and survival in hatchery reared lobster juveniles.

  19. [Internal migration studies].

    Science.gov (United States)

    Stpiczynski, T

    1986-10-01

    Recent research on internal migration in Poland is reviewed. The basic sources of data, consisting of censuses or surveys, are first described. The author discusses the relationship between migration studies and other sectors of the national economy, and particularly the relationship between migration and income.

  20. Effects of Prior Experience on Shelter-Seeking Behavior of Juvenile American Lobsters.

    Science.gov (United States)

    Bayer, Skylar R; Bianchi, Katherine M; Atema, Jelle; Jacobs, Molly W

    2017-04-01

    Shelter-seeking behaviors are vital for survival for a range of juvenile benthic organisms. These behaviors may be innate or they may be affected by prior experience. After hatching, American lobsters Homarus americanus likely first come into contact with shelter during the late postlarval (decapodid) stage, known as stage IV. After the subsequent molt to the first juvenile stage (stage V), they are entirely benthic and are thought to be highly cryptic. We hypothesized that postlarval (stage IV) experience with shelter would carry over into the first juvenile stage (stage V) and reduce the time needed for juveniles to locate and enter shelters (sheltering). We found some evidence of a carryover effect, but not the one we predicted: stage V juveniles with postlarval shelter experience took significantly longer to initiate sheltering. We also hypothesized that stage V juveniles would demonstrate learning by relocating shelters more quickly with immediate prior experience. Our findings were mixed. In a maze, juveniles with immediate prior experience were faster to regain visual contact with shelter, suggesting that they had learned the location of the shelter. In contrast, there was no significant effect of immediate prior experience on time to initiate sheltering in an open arena, or in the maze after juveniles had regained visual contact. We conclude that very young (stage V) juvenile lobsters modify their shelter-seeking behavior based on prior experiences across several timescales. Ecologically relevant variation in habitat exposure among postlarval and early juvenile lobsters may influence successful recruitment in this culturally and commercially important fishery species.

  1. Seismic imaging of complex subsurface in areas with rugged topography and crooked-line geometries. 1. Time migration and dipmoveout; Rikujo nanchiiki data ni kansuru imaging shori no mondaiten. 1. Jikan ryoiki shori

    Energy Technology Data Exchange (ETDEWEB)

    Age, S; Ota, Y [Japex Jeoscience Institute, Tokyo (Japan); Matsuoka, T [Japan Petroleum Exploration Corp., Tokyo (Japan); Minegishi, M [Japan National Oil Corp., Tokyo (Japan). Technology Research Center

    1997-10-22

    Concerning the analysis of data from seismic reflection survey, time migration and DMO treatment are discussed. As a tool for dealing with irregular changes in elevation, a technique is developed that can define the local reference level working effectively in the Kirchhoff-type treatment. In this technique, for each migration or dipmovement trace outputted, processing is repeatedly performed for imaging and local reference level. In dealing with the curvature of a traverse line, a 3-dimensional DMO treatment with cross-dip correction is performed, for the development of a method for simultaneously applying projection and accumulation to stacked traverse lines. A migration projection plane is set separately from the CMP traverse line, and this enables a quasi-3-dimensional treatment approximately corresponding to the curvature of the traverse line. A technique to respond to irregular shock points is discussed, in which input traces corrected by NMO having uniform amplitude distribution are presumed, DMO treatment is conducted for each irregular shock point, and the results are used as a normalization factor usable in the process of real DMO stacking. 6 refs., 2 figs.

  2. Time-dependent migration of citations through PubMed and OvidSP subsets: a study on a series of simultaneous PubMed and OvidSP searches.

    Science.gov (United States)

    Boeker, Martin; Vach, Werner; Motschall, Edith

    2013-01-01

    To quantitatively describe (1) differences between search results derived at consecutive time points with the PubMed and OvidSP literature search interfaces over a five day interval, and (2) the migration of citations through different subsets to estimate the timeliness of OvidSP. PubMed-Identifiers (PMIDs) of the following subsets were retrieved from PubMed and OvidSP simultaneously (within 8 h) at 11 days in March and April 2010 including 5 consecutive days: as supplied by publisher, in process, PubMed not MEDLINE, and OLDMEDLINE. Search results were compared for difference and intersection sets. The migration of citations on individual level was determined by comparison of corresponding sets over several days. The "in process" set was stable with about 446,000 - 452,000 citations; a small fraction of up to 3 % of the total subsets were in PubMed only and OvidSP only subsets. About 96 % of the ca. 10,500 citations in the OvidSP only subset migrated within 2 days out of the "in process" subset. The database of OvidSP is updated within a period of two days.

  3. A Practical Approach to Juvenile Dermatomyositis and Juvenile Scleroderma.

    Science.gov (United States)

    McCann, Liza J; Pain, Clare E

    2016-02-01

    Juvenile dermatomyositis and juvenile scleroderma are rare multisystem autoimmune disorders. Although they share some pathognomonic hallmarks with adult onset myositis or scleroderma, there are significant differences in presentation, characteristics and associated features when the diseases present in childhood. In view of this, and the rarity of the conditions, it is important for care to be led by teams with expertise in pediatric rheumatology conditions. Prognosis has improved significantly in the West; likely due to early diagnosis and aggressive treatment with immunosuppressive medications. However, this trend is not replicated in the developing world. Early recognition of these diseases is crucial to achieve rapid and sustained remission and prevent disease or medication associated complications. This article aims to provide a practical overview for recognition, diagnosis and treatment of these conditions.

  4. Morphological constraints on changing avian migration phenology.

    Science.gov (United States)

    Møller, A P; Rubolini, D; Saino, N

    2017-06-01

    Many organisms at northern latitudes have responded to climate warming by advancing their spring phenology. Birds are known to show earlier timing of spring migration and reproduction in response to warmer springs. However, species show heterogeneous phenological responses to climate warming, with those that have not advanced or have delayed migration phenology experiencing population declines. Although some traits (such as migration distance) partly explain heterogeneity in phenological responses, the factors affecting interspecies differences in the responsiveness to climate warming have yet to be fully explored. In this comparative study, we investigate whether variation in wing aspect ratio (reflecting relative wing narrowness), an ecomorphological trait that is strongly associated with flight efficiency and migratory behaviour, affects the ability to advance timing of spring migration during 1960-2006 in a set of 80 European migratory bird species. Species with larger aspect ratio (longer and narrower wings) showed smaller advancement of timing of spring migration compared to species with smaller aspect ratio (shorter and wider wings) while controlling for phylogeny, migration distance and other life-history traits. In turn, migration distance positively predicted aspect ratio across species. Hence, species that are better adapted to migration appear to be more constrained in responding phenologically to rapid climate warming by advancing timing of spring migration. Our findings corroborate the idea that aspect ratio is a major evolutionary correlate of migration, and suggest that selection for energetically efficient flights, as reflected by high aspect ratio, may hinder phenotypically plastic/microevolutionary adjustments of migration phenology to ongoing climatic changes. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  5. The Psychology of Puerto Rican Migration.

    Science.gov (United States)

    Prewitt Diaz, Joseph O.

    The psychology of the Puerto Rican migrant to the United States mainland is explored. Puerto Ricans have been migrating to the U.S. mainland and returning to Puerto Rico for more than 125 years, and, in fact, approximately 57% of all Puerto Ricans have migrated at one time or another. The migrant experience, including the circular migration…

  6. Husbands' return migration and wives' occupational choices

    NARCIS (Netherlands)

    Mahe, Clotilde

    2017-01-01

    Exploiting the documented effect of migration on occupational choice upon return to their origin country with data from Egypt, we establish a link between return migration of men and their wives' time use through within-couple occupational interdependence. Seemingly Unrelated Regression model

  7. Job Migration: A Collaborative Effort

    Science.gov (United States)

    Wagoner, Cynthia L.

    2012-01-01

    Music teachers often change jobs several times during their careers. Reasons for job changes vary, but regardless, these changes bring a different set of challenges. Sharing knowledge and learning are part and parcel of collaboration. So what if, as education professionals, music teachers decided to collaborate during job migrations? For all music…

  8. Ecological carryover effects associated with partial migration in white perch (Morone americana) within the Hudson River Estuary

    Science.gov (United States)

    Gallagher, Brian K.; Piccoli, Philip M.; Secor, David H.

    2018-01-01

    Partial migration in complex life cycles allows environmental conditions experienced during one life-stage to interact with genetic thresholds and produce divergent spatial behaviors in the next stage. We evaluated partial migration over the entire life cycle of white perch, (Morone americana) within the Hudson River Estuary, combining otolith microchemistry, population demographics and environmental data analysis. Ecological carryover effects were used as a framework to test how environmental variation during the larval period influenced migration behaviors and growth characteristics in subsequent life-stages. Two annual cohorts of juveniles were classified based on whether they persisted in natal habitats (freshwater resident contingent) or dispersed into non-natal habitats (brackish water migratory contingent) as juveniles. The migratory contingent tended to hatch earlier and experience cooler temperatures as larvae, while the availability of zooplankton prey during the larval period appeared to influence growth dynamics before and after metamorphosis. Juvenile migration behaviors were reversible but usually persisted into adulthood. As juveniles, the consequences of partial migration on growth appeared to be modified by river flow, as demonstrated by the influence of a large storm event on feeding conditions in one of the study years. Migratory adults grew faster and attained larger maximum sizes, but may also experience higher rates of mortality. The interplay uncovered between life-stage transitions, conditional migration behaviors and habitat productivity throughout the life cycle shapes white perch population dynamics and will likely play an important role in responses to long-term environmental change.

  9. Depth migration and de-migration for 3-D migration velocity analysis; Migration profondeur et demigration pour l'analyse de vitesse de migration 3D

    Energy Technology Data Exchange (ETDEWEB)

    Assouline, F.

    2001-07-01

    3-D seismic imaging of complex geologic structures requires the use of pre-stack imaging techniques, the post-stack ones being unsuitable in that case. Indeed, pre-stack depth migration is a technique which allows to image accurately complex structures provided that we have at our disposal a subsurface velocity model accurate enough. The determination of this velocity model is thus a key element for seismic imaging, and to this end, migration velocity analysis methods have met considerable interest. The SMART method is a specific migration velocity analysis method: the singularity of this method is that it does not rely on any restrictive assumptions on the complexity of the velocity model to determine. The SMART method uses a detour through the pre-stack depth migrated domain for extracting multi-offset kinematic information hardly accessible in the time domain. Once achieved the interpretation of the pre-stack depth migrated seismic data, a kinematic de-migration technique of the interpreted events enables to obtain a consistent kinematic database (i.e. reflection travel-times). Then, the inversion of these travel-times, by means of reflection tomography, allows the determination of an accurate velocity model. To be able to really image geologic structures for which the 3-D feature is predominant, we have studied the implementation of migration velocity analysis in 3-D in the context of the SMART method, and more generally, we have developed techniques allowing to overcome the intrinsic difficulties in the 3-D aspects of seismic imaging. Indeed, although formally the SMART method can be directly applied to the case of 3-D complex structures, the feasibility of its implementation requires to choose well the imaging domain. Once this choice done, it is also necessary to conceive a method allowing, via the associated de-migration, to obtain the reflection travel-times. We first consider the offset domain which constitutes, still today, the strategy most usually used

  10. Chasing migration genes: a brain expressed sequence tag resource for summer and migratory monarch butterflies (Danaus plexippus.

    Directory of Open Access Journals (Sweden)

    Haisun Zhu

    2008-01-01

    Full Text Available North American monarch butterflies (Danaus plexippus undergo a spectacular fall migration. In contrast to summer butterflies, migrants are juvenile hormone (JH deficient, which leads to reproductive diapause and increased longevity. Migrants also utilize time-compensated sun compass orientation to help them navigate to their overwintering grounds. Here, we describe a brain expressed sequence tag (EST resource to identify genes involved in migratory behaviors. A brain EST library was constructed from summer and migrating butterflies. Of 9,484 unique sequences, 6068 had positive hits with the non-redundant protein database; the EST database likely represents approximately 52% of the gene-encoding potential of the monarch genome. The brain transcriptome was cataloged using Gene Ontology and compared to Drosophila. Monarch genes were well represented, including those implicated in behavior. Three genes involved in increased JH activity (allatotropin, juvenile hormone acid methyltransfersase, and takeout were upregulated in summer butterflies, compared to migrants. The locomotion-relevant turtle gene was marginally upregulated in migrants, while the foraging and single-minded genes were not differentially regulated. Many of the genes important for the monarch circadian clock mechanism (involved in sun compass orientation were in the EST resource, including the newly identified cryptochrome 2. The EST database also revealed a novel Na+/K+ ATPase allele predicted to be more resistant to the toxic effects of milkweed than that reported previously. Potential genetic markers were identified from 3,486 EST contigs and included 1599 double-hit single nucleotide polymorphisms (SNPs and 98 microsatellite polymorphisms. These data provide a template of the brain transcriptome for the monarch butterfly. Our "snap-shot" analysis of the differential regulation of candidate genes between summer and migratory butterflies suggests that unbiased, comprehensive

  11. Chasing Migration Genes: A Brain Expressed Sequence Tag Resource for Summer and Migratory Monarch Butterflies (Danaus plexippus)

    Science.gov (United States)

    Zhu, Haisun; Casselman, Amy; Reppert, Steven M.

    2008-01-01

    North American monarch butterflies (Danaus plexippus) undergo a spectacular fall migration. In contrast to summer butterflies, migrants are juvenile hormone (JH) deficient, which leads to reproductive diapause and increased longevity. Migrants also utilize time-compensated sun compass orientation to help them navigate to their overwintering grounds. Here, we describe a brain expressed sequence tag (EST) resource to identify genes involved in migratory behaviors. A brain EST library was constructed from summer and migrating butterflies. Of 9,484 unique sequences, 6068 had positive hits with the non-redundant protein database; the EST database likely represents ∼52% of the gene-encoding potential of the monarch genome. The brain transcriptome was cataloged using Gene Ontology and compared to Drosophila. Monarch genes were well represented, including those implicated in behavior. Three genes involved in increased JH activity (allatotropin, juvenile hormone acid methyltransfersase, and takeout) were upregulated in summer butterflies, compared to migrants. The locomotion-relevant turtle gene was marginally upregulated in migrants, while the foraging and single-minded genes were not differentially regulated. Many of the genes important for the monarch circadian clock mechanism (involved in sun compass orientation) were in the EST resource, including the newly identified cryptochrome 2. The EST database also revealed a novel Na+/K+ ATPase allele predicted to be more resistant to the toxic effects of milkweed than that reported previously. Potential genetic markers were identified from 3,486 EST contigs and included 1599 double-hit single nucleotide polymorphisms (SNPs) and 98 microsatellite polymorphisms. These data provide a template of the brain transcriptome for the monarch butterfly. Our “snap-shot” analysis of the differential regulation of candidate genes between summer and migratory butterflies suggests that unbiased, comprehensive transcriptional profiling

  12. Migration processes in SCO member states

    Directory of Open Access Journals (Sweden)

    Valentina Sergeevna Antonyuk

    2012-12-01

    Full Text Available The article concerns modern state and development of migration processes in SCO member states. As a main method of research statistical analysis was applied. The article shows that migration streams between SCO member states are rather intensive, and the problem of labor migration becomes more and more urgent. The countries of consuming and supplying of labour force are clearly differentiated in the region. For some countries, labor export is the key sector of economy. At the same time, interstate relations between SCO member states sometimes are rather disputed. The most urgent factors causing the development of migration processes in the region were determined. Among them, thefactor of growing outflows from China isespecially noted. It is noted that migration processes are discussed by SCO member states nowadays in terms of illegal migration and international criminality connected with it. It means that the question of labor migration is a real problem. It is indicated that the creation of a specific joint commission on migration policy affiliated with the Council of Foreign Ministers of SCO member states is the necessary condition of effective interaction in migration questions within the framework of Shanghai Cooperation Organization.

  13. Investigations of the migrating motor complex in domestic turkeys.

    Science.gov (United States)

    Mueller, L R; Duke, G E; Evanson, O A

    1990-09-01

    The motor correlate of the migrating myoelectric complex (MMC) was characterized in domestic turkeys, and feeding state, age, sex, and time of day were examined as possible factors influencing the motor activity observed. Strain gauge transducers, and in a few birds Ag-AgCl bipolar electrodes, were implanted on the caudoventral thin muscle of the muscular stomach, the duodenum, ileum, cecum, and colon. Contractility was recorded for 8-10 h per bird on alternating days for 2-3 wk, except in birds involved in four 24-h recording sessions during a 2-wk period. Intense motor activity characteristic of phase III of the MMC occurred only in the ileum; other phases could not be identified. The duration, propagation velocity, and percent of cyclic motor patterns propagating from one site to another were similar to those reported in other galliform species. The occurrence of cyclic motor activity appeared to be related to food consumption; the number of motor patterns occurring during an intense feeding session was less than the number observed 1.5-2 h after feeding. In addition, more motor patterns were recorded in fasted poults during the light period than in the dark; however, the reverse was observed in juveniles fed ad libitum. Cyclic motor activity recorded in fasted 18-wk-old birds was of longer duration than that in fasted 8-wk-old birds. No statistically significant differences were noted in the cyclic motor patterns of male vs. female poults.

  14. Juvenile morphology in baleen whale phylogeny.

    Science.gov (United States)

    Tsai, Cheng-Hsiu; Fordyce, R Ewan

    2014-09-01

    Phylogenetic reconstructions are sensitive to the influence of ontogeny on morphology. Here, we use foetal/neonatal specimens of known species of living baleen whales (Cetacea: Mysticeti) to show how juvenile morphology of extant species affects phylogenetic placement of the species. In one clade (sei whale, Balaenopteridae), the juvenile is distant from the usual phylogenetic position of adults, but in the other clade (pygmy right whale, Cetotheriidae), the juvenile is close to the adult. Different heterochronic processes at work in the studied species have different influences on juvenile morphology and on phylogenetic placement. This study helps to understand the relationship between evolutionary processes and phylogenetic patterns in baleen whale evolution and, more in general, between phylogeny and ontogeny; likewise, this study provides a proxy how to interpret the phylogeny when fossils that are immature individuals are included. Juvenile individuals in the peramorphic acceleration clades would produce misleading phylogenies, whereas juvenile individuals in the paedomorphic neoteny clades should still provide reliable phylogenetic signals.

  15. Yolo Bypass Juvenile Salmon Utilization Study 2016—Summary of acoustically tagged juvenile salmon and study fish release, Sacramento River, California

    Science.gov (United States)

    Liedtke, Theresa L.; Hurst, William R.

    2017-09-12

    The Yolo Bypass is a flood control bypass in Sacramento Valley, California. Flood plain habitats may be used for juvenile salmon rearing, however, the potential value of such habitats can be difficult to evaluate because of the intermittent nature of inundation events. The Yolo Bypass Juvenile Salmon Utilization Study (YBUS) used acoustic telemetry to evaluate the movements and survival of juvenile salmon adjacent to and within the Yolo Bypass during the winter of 2016. This report presents numbers, size data, and release data (times, dates, and locations) for the 1,197 acoustically tagged juvenile salmon released for the YBUS from February 21 to March 18, 2016. Detailed descriptions of the surgical implantation of transmitters are also presented. These data are presented to support the collaborative, interagency analysis and reporting of the study findings.

  16. An unusual presentation of juvenile lupus nephritis

    Directory of Open Access Journals (Sweden)

    Malleshwar Bottu

    2016-01-01

    Full Text Available The incidence of juvenile lupus varies widely ranging between 4 and 250 per 100,000 population. Most common organ involvement in juvenile lupus is kidney. Neurological, cutaneous and hematological involvements are also involved. Skeletal muscle involvement in the form of myositis is rare. Myositis as presenting manifestation in juvenile lupus is also unusual. Herein, we report one such case wherein myositis preceded the onset of lupus nephritis

  17. Tracking migrating birds

    DEFF Research Database (Denmark)

    Willemoes, Mikkel

    habitats with those in rural habitats. Some species have decreased the frequency of migrants and migration distance in urban environments, and others have not. The other manuscript describes the small scale movements of three different Palaearctic migrants during winter in Africa in a farmland habitat....... In another species, environmental conditions are not a good predictor of movements, and possibly effects of timing constraints or food type play a role. Two manuscripts focus on the effects of human-induced habitat alterations on migratory behaviour. One compares the movements of partial migrants in urban...... and a forest reserve. In the degraded habitat all species used more space, although the consequence on bird density is less clear. Two manuscripts relate the migratory movements of a long-distance migrant with models of navigation. One compares model predictions obtained by simulation with actual movements...

  18. Juvenile offenders: competence to stand trial.

    Science.gov (United States)

    Soulier, Matthew

    2012-12-01

    This article details the legal background and assists the reader in the preparation and practical conduct of evaluations regarding juvenile adjudicative competency. The material is presented to be useful as a guide to direct questions of competency and covers aspects of evaluation that include: legal standard for competency to stand trial, developmental immaturity, current practice in juvenile competency to stand trial, forensic evaluation of juvenile competency to stand trial, organizing the evaluation, collateral sources of information, psychiatric evaluation of juvenile adjudicative competency, assessment of mental disorder and intellectual disability, assessment of developmental status, assessment of functional abilities for adjudicative competence, and reaching the forensic opinion. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. Fish Individual-based Numerical Simulator (FINS): A particle-based model of juvenile salmonid movement and dissolved gas exposure history in the Columbia River Basin

    International Nuclear Information System (INIS)

    Scheibe, Timothy D.; Richmond, Marshall C.

    2002-01-01

    This paper describes a numerical model of juvenile salmonid migration in the Columbia and Snake Rivers. The model, called the Fish Individual-based Numerical Simulator or FINS, employs a discrete, particle-based approach to simulate the migration and history of exposure to dissolved gases of individual fish. FINS is linked to a two-dimensional (vertically-averaged) hydrodynamic simulator that quantifies local water velocity, temperature, and dissolved gas levels as a function of river flow rates and dam operations. Simulated gas exposure histories can be input to biological mortality models to predict the effects of various river configurations on fish injury and mortality due to dissolved gas supersaturation. Therefore, FINS serves as a critical linkage between hydrodynamic models of the river system and models of biological impacts. FINS was parameterized and validated based on observations of individual fish movements collected using radiotelemetry methods during 1997 and 1998 . A quasi-inverse approach was used to decouple fish swimming movements from advection with the local water velocity, allowing inference of time series of non-advective displacements of individual fish from the radiotelemetry data. Statistical analyses of these displacements are presented, and confirm that strong temporal correlation of fish swimming behavior persists in some cases over several hours. A correlated random-walk model was employed to simulate the observed migration behavior, and parameters of the model were estimated that lead to close correspondence between predictions and observations

  20. Vertical self-sorting behavior in juvenile Chinook salmon (Oncorhynchus tshawytscha): evidence for family differences and variation in growth and morphology

    Science.gov (United States)

    Unrein, Julia R.; Billman, E.J.; Cogliati, Karen M.; Chitwood, Rob S.; Noakes, David L. G.; Schreck, Carl B.

    2018-01-01

    Life history variation is fundamental to the evolution of Pacific salmon and their persistence under variable conditions. We discovered that Chinook salmon sort themselves into surface- and bottom-oriented groups in tanks within days after exogenous feeding. We hypothesised that this behaviour is correlated with subsequent differences in body morphology and growth (as measured by final length and mass) observed later in life. We found consistent morphological differences between surface and bottom phenotypes. Furthermore, we found that surface and bottom orientation within each group is maintained for at least one year after the phenotypes were separated. These surface and bottom phenotypes are expressed across genetic stocks, brood years, and laboratories and we show that the proportion of surface- and bottom-oriented offspring also differed among families. Importantly, feed delivery location did not affect morphology or growth, and the surface fish were longer than bottom fish at the end of the rearing experiment. The body shape of the former correlates with wild individuals that rear in mainstem habitats and migrate in the fall as subyearlings and the latter resemble those that remain in the upper tributaries and migrate as yearling spring migrants. Our findings suggest that early self-sorting behaviour may have a genetic basis and be correlated with other phenotypic traits that are important indicators for juvenile migration timing.

  1. Radon depth migration

    International Nuclear Information System (INIS)

    Hildebrand, S.T.; Carroll, R.J.

    1993-01-01

    A depth migration method is presented that used Radon-transformed common-source seismograms as input. It is shown that the Radon depth migration method can be extended to spatially varying velocity depth models by using asymptotic ray theory (ART) to construct wavefield continuation operators. These operators downward continue an incident receiver-array plane wave and an assumed point-source wavefield into the subsurface. The migration velocity model is constrain to have longer characteristic wavelengths than the dominant source wavelength such that the ART approximations for the continuation operators are valid. This method is used successfully to migrate two synthetic data examples: (1) a point diffractor, and (2) a dipping layer and syncline interface model. It is shown that the Radon migration method has a computational advantage over the standard Kirchhoff migration method in that fewer rays are computed in a main memory implementation

  2. Migration into art

    DEFF Research Database (Denmark)

    Petersen, Anne Ring

    This book addresses a topic of increasing importance to artists, art historians and scholars of cultural studies, migration studies and international relations: migration as a profoundly transforming force that has remodelled artistic and art institutional practices across the world. It explores...... contemporary art's critical engagement with migration and globalisation as a key source for improving our understanding of how these processes transform identities, cultures, institutions and geopolitics. The author explores three interwoven issues of enduring interest: identity and belonging, institutional...

  3. Foraging behaviour of juvenile female New Zealand sea lions (Phocarctos hookeri in contrasting environments.

    Directory of Open Access Journals (Sweden)

    Elaine S Leung

    Full Text Available Foragers can show adaptive responses to changes within their environment through morphological and behavioural plasticity. We investigated the plasticity in body size, at sea movements and diving behaviour of juvenile female New Zealand (NZ sea lions (Phocarctos hookeri in two contrasting environments. The NZ sea lion is one of the rarest pinnipeds in the world. Most of the species is based at the subantarctic Auckland Islands (AI; considered to be marginal foraging habitat, with a recolonizing population on the Otago Peninsula, NZ mainland (considered to be more optimal habitat. We investigated how juvenile NZ sea lions adjust their foraging behaviour in contrasting environments by deploying satellite-linked platform transmitting terminals (PTTs and time-depth recorders (TDRs on 2-3 year-old females at AI (2007-2010 and Otago (2009-2010. Juvenile female NZ sea lions exhibited plasticity in body size and behaviour. Otago juveniles were significantly heavier than AI juveniles. Linear mixed effects models showed that study site had the most important effect on foraging behaviour, while mass and age had little influence. AI juveniles spent more time at sea, foraged over larger areas, and dove deeper and longer than Otago juveniles. It is difficult to attribute a specific cause to the observed contrasts in foraging behaviour because these differences may be driven by disparities in habitat/prey characteristics, conspecific density levels or interseasonal variation. Nevertheless, the smaller size and increased foraging effort of AI juveniles, combined with the lower productivity in this region, support the hypothesis that AI are less optimal habitat than Otago. It is more difficult for juveniles to forage in suboptimal habitats given their restricted foraging ability and lower tolerance for food limitation compared to adults. Thus, effective management measures should consider the impacts of low resource environments, along with changes that can

  4. Regional Redistribution and Migration

    DEFF Research Database (Denmark)

    Manasse, Paolo; Schultz, Christian

    We study a model with free migration between a rich and a poor region. Since there is congestion, the rich region has an incentive to give the poor region a transfer in order to reduce immigration. Faced with free migration, the rich region voluntarily chooses a transfer, which turns out...... to be equal to that a social planner would choose. Provided migration occurs in equilibrium, this conclusion holds even in the presence of moderate mobility costs. However, large migration costs will lead to suboptimal transfers in the market solution...

  5. Impact of temperature and storage time on the migration of antimony from polyethylene terephthalate (PET) containers into bottled water in Qatar.

    Science.gov (United States)

    Al-Otoum, Fatima; Al-Ghouti, Mohammad A; Costa, Ozeas S; Khraisheh, Majeda

    2017-11-12

    Prosperity in Qatar and the consequent stresses on water resources resulted in a sustainable increase in the bottled drinking water market. Reports on health concerns and possible migration of chemicals from the plastic material into the water have driven the current investigation. This study aims to address the extent of antimony (Sb) leaching from polyethylene terephthalate (PET) water bottles subject to temperature variations (24-50 °C) due to Qatar's hot climate and improper storage conditions. A representative basket including 66 different imported and locally produced water bottles was considered. The concentrations of Sb in bottled water ranged from 0.168 to 2.263 μg/L at 24 °C and from 0.240 to 6.110 μg/L at 50 °C. Antimony concentrations in PET bottles at 24 °C was significantly lower than those at 50 °C (p = 0.0142), indicating that the temperature was a principal factor affecting the release of Sb from the plastic into the water. Although the detected Sb amounts were below the guidelines endorsed by WHO and Qatar (standard 5 μg/L) at 24 °C, the concentration measured at 50 °C was higher than the recommended WHO values (6.11 μg/L).

  6. HLA antigens in juvenile onset diabetes.

    Science.gov (United States)

    Kikuchi, T; Toyota, T; Ouchi, E

    1980-11-01

    To study association between juvenile onset diabetes (JOD) and major histocompatibility gene complex, 40 patients with childhood onset diabetes and 120 healthy subjects were typed for HLA. Bw54 was present in 33 percent of the patients with JOD, while it appeared in 8 percent of the controls. Expressed as a relative risk, the antigen Bw54 confers a susceptibility to the development of JOD which is 5.3 times that in the controls. JOD shows a little high degree of association with A9 (78%). However, the A9-antigen is common in the Japanese and appears in 58 percent. Though less striking, the decreased frequency of B12 was 3 percent of JOD, less than 15 percent of the controls (p less than 0.05). There was no association between Bw54 and JOD with family history of diabetes.

  7. The migration game in habitat network: the case of tuna

    DEFF Research Database (Denmark)

    Mariani, Patrizio; Krivan, Vlastimil; MacKenzie, Brian

    2016-01-01

    migration in direction of increasing fitness should lead to the ideal free distribution (IFD) which is the evolutionary stable strategy of the habitat selection game. We introduce a migration game which focuses on migrating dynamics leading to the IFD for age-structured populations and in time varying...

  8. A lean and mean strategy: a data migration industrial study

    NARCIS (Netherlands)

    Razavian, M.; Lago, P.

    2014-01-01

    Many companies have legacy assets to be integrated or modernized. Like today's software developments, migration projects are faced with steadily increasing demands for efficiency: migration has to be carried out faster, better, and cheaper. At the same time, migration complexity increases, and

  9. Eugenol as an anesthetic for juvenile common snook

    Directory of Open Access Journals (Sweden)

    Jurandir Joaquim Bernardes Júnior

    2013-08-01

    Full Text Available The objective of this work was to evaluate the efficacy of eugenol as an anesthetic for juvenile common snook, and to determine the minimum effective concentration for use in handling procedures. In the first trial, juvenile common snook were subjected to immersion baths at 25, 50, 75, 100, 125, and 150 mg L-1 eugenol concentrations, after which induction and recovery times were evaluated. In the second experiment, the lethal exposure time (LT50 at 75 mg L-1 was estimated. Minimum effective eugenol concentration was 50 mg L-1, andthe stage of deep anesthesia and recovery were, respectively, reached at 126.3 and 208.8 s. At 75 mg L-1, LT50 was 1,314 s, and induction time and recovery were also satisfactory; however, fish cannot tolerate over 229 s exposure.

  10. The effects of violence exposure on the development of impulse control and future orientation across adolescence and early adulthood: Time-specific and generalized effects in a sample of juvenile offenders.

    Science.gov (United States)

    Monahan, Kathryn C; King, Kevin M; Shulman, Elizabeth P; Cauffman, Elizabeth; Chassin, Laurie

    2015-11-01

    Impulse control and future orientation increase across adolescence, but little is known about how contextual factors shape the development of these capacities. The present study investigates how stress exposure, operationalized as exposure to violence, alters the developmental pattern of impulse control and future orientation across adolescence and early adulthood. In a sample of 1,354 serious juvenile offenders, higher exposure to violence was associated with lower levels of future orientation at age 15 and suppressed development of future orientation from ages 15 to 25. Increases in witnessing violence or victimization were linked to declines in impulse control 1 year later, but only during adolescence. Thus, beyond previous experiences of exposure to violence, witnessing violence and victimization during adolescence conveys unique risk for suppressed development of self-regulation.

  11. Regulators of Intestinal Epithelial Migration in Sepsis.

    Science.gov (United States)

    Meng, Mei; Klingensmith, Nathan J; Liang, Zhe; Lyons, John D; Fay, Katherine T; Chen, Ching-Wen; Ford, Mandy L; Coopersmith, Craig M

    2018-02-08

    The gut is a continuously renewing organ, with cell proliferation, migration and death occurring rapidly under basal conditions. Since the impact of critical illness on cell movement from crypt base to villus tip is poorly understood, the purpose of this study was to determine how sepsis alters enterocyte migration. Wild type, transgenic and knockout mice were injected with 5-bromo-2'deoxyuridine (BrdU) to label cells in S phase before and after the onset of cecal ligation and puncture and were sacrificed at pre-determined endpoints to determine distance proliferating cells migrated up the crypt-villus unit. Enterocyte migration rate was decreased from 24-96 hours following sepsis. BrdU was not detectable on villi 6 days after sham laparotomy, meaning all cells had migrated the length of the gut and been exfoliated into its lumen. However, BrdU positive cells were detectable on villi 10 days after sepsis. Multiple components of gut integrity altered enterocyte migration. Sepsis decreased crypt proliferation, which further slowed enterocyte transit as mice injected with BrdU after the onset of sepsis (decreased proliferation) had slower migration than mice injected with BrdU prior to the onset of sepsis (normal proliferation). Decreasing intestinal apoptosis via gut-specific overexpression of Bcl-2 prevented sepsis-induced slowing of enterocyte migration. In contrast, worsened intestinal hyperpermeability by genetic deletion of JAM-A increased enterocyte migration. Sepsis therefore significantly slows enterocyte migration, and intestinal proliferation, apoptosis and permeability all affect migration time, which can potentially be targeted both genetically and pharmacologically.

  12. Excretory nitrogen metabolism in the juvenile axolotl Ambystoma mexicanum: differences in aquatic and terrestrial environments.

    Science.gov (United States)

    Loong, Ai M; Chew, Shit F; Ip, Yuen K

    2002-01-01

    The fully grown but nonmetamorphosed (juvenile) axolotl Ambystoma mexicanum was ureogenic and primarily ureotelic in water. A complete ornithine-urea cycle (OUC) was present in the liver. Aerial exposure impeded urea (but not ammonia) excretion, leading to a decrease in the percentage of nitrogen excreted as urea in the first 24 h. However, urea and not ammonia accumulated in the muscle, liver, and plasma during aerial exposure. By 48 h, the rate of urea excretion recovered fully, probably due to the greater urea concentration gradient in the kidney. It is generally accepted that an increase in carbamoyl phosphate synthetase activity is especially critical in the developmental transition from ammonotelism to ureotelism in the amphibian. Results from this study indicate that such a transition in A. mexicanum would have occurred before migration to land. Aerial exposure for 72 h exhibited no significant effect on carbamoyl phosphate synthetase-I activity or that of other OUC enzymes (with the exception of ornithine transcarbamoylase) from the liver of the juvenile A. mexicanum. This supports our hypothesis that the capacities of OUC enzymes present in the liver of the aquatic juvenile axolotl were adequate to prepare it for its invasion of the terrestrial environment. The high OUC capacity was further supported by the capability of the juvenile A. mexicanum to survive in 10 mM NH(4)Cl without accumulating amino acids in its body. The majority of the accumulating endogenous and exogenous ammonia was detoxified to urea, which led to a greater than twofold increase in urea levels in the muscle, liver, and plasma and a significant increase in urea excretion by hour 96. Hence, it can be concluded that the juvenile axolotl acquired ureotelism while submerged in water, and its hepatic capacity of urea synthesis was more than adequate to handle the toxicity of endogenous ammonia during migration to land.

  13. Prestack exploding reflector modeling and migration in TI media

    KAUST Repository

    Wang, H.

    2014-01-01

    Prestack depth migration in anisotropic media, especially those that exhibit tilt, can be costly using reverse time migration (RTM). We present two-way spectral extrapolation of prestack exploding reflector modeling and migration (PERM) in acoustic transversely isotropic (TI) media. We construct systematic ways to evaluate phase angles and phase velocities in dip oriented TI (DTI), vertical TI (VTI) and tilted TI (TTI) media. Migration results from the Marmousi VTI model and the BP2007 TTI model show the feasibility of our approach.

  14. Migration: the trends converge.

    Science.gov (United States)

    1985-09-01

    Formerly, Australia, New Zealand, Canada, and the US have served as permanent destinations for immigrants, while Europe's migrants have moved to more northerly countries to work for a time and then returned home. From 1973-1975 Europe's recruitment of foreign workers virtually ended, although family reunion for those immigrants allowed in was encouraged. Problems resulting from this new settlement migration include low paying jobs for immigrant women, high unemployment, and inadequate education for immigrant children. Illegal migrants from Latin America and the Caribbean enter the US and Canada each year while illegal North African immigrants enter Italy, Spain, and Greece. North America, Australia, and Europe have all received political refugees from Asia and Latin America. Increasingly, these foreigners compete in the labor market rather than simply fill jobs the native workers do not want. All the receiving countries have similar policy priorities: 1) more effective ways for controlling and monitoring inflows and checking illegal immigration; 2) encouraging normal living patterns and accepting refugees; and 3) integrating permanent migrants into the host country. Europe's public immigration encouragement prior to the first oil shock, has left some countries with a labor force that is reluctant to return home. It is unlikely that Europe will welcome foreign labor again in this decade, since unemployment among young people and women is high and family reunion programs may still bring in many immigrants. Less immigration pattern change will probably occur in North America, Australia, and New Zealand since these countries' populations are still growing and wages are more flexible. Immigration, regulated by policy, and emigration, determined by market forces, now are working in the same direction and will likely reduce future migration flows.

  15. Gas bubble trauma monitoring and research of juvenile salmonids. 1995 Annual report

    International Nuclear Information System (INIS)

    Maule, A.G.; Mesa, M.G.; Hans, K.M.

    1997-07-01

    This report describes laboratory and field monitoring studies of gas bubble trauma (GBT) in migrating juvenile salmonids in the Snake and Columbia rivers. The first chapter describes laboratory studies of the progression of GBT signs leading to mortality and the use of the signs for GBT assessment. The progression and severity of GBT signs in juvenile salmonids exposed to different levels of total dissolved gas (TDG) and temperatures was assessed and quantified. Next, the prevalence, severity, and individual variation of GBT signs was evaluated to attempt to relate them to mortality. Finally, methods for gill examination in fish exposed to high TDG were developed and evaluated. Primary findings were: (1) no single sign of GBT was clearly correlated with mortality, but many GBT signs progressively worsened; (2) both prevalence and severity of GBT signs in several tissues is necessary; (3) bubbles in the lateral line were the earliest sign of GBT, showed progressive worsening, and had low individual variation but may develop poorly during chronic exposures; (4) fin bubbles had high prevalence, progressively worsened, and may be a persistent sign of GBT; and (5) gill bubbles appear to be the proximate cause of death but may only be relevant at high TDG levels and are difficult to examine. Chapter Two describes monitoring results of juvenile salmonids for signs of GBT. Emigrating fish were collected and examined for bubbles in fins and lateral lines. Preliminary findings were: (1) few fish had signs of GBT, but prevalence and severity appeared to increase as fish migrated downstream; (2) there was no apparent correlation between GBT signs in the fins, lateral line, or gills; (3) prevalence and severity of GBT was suggestive of long-term, non-lethal exposure to relatively low level gas supersaturated water; and (4) it appeared that GBT was not a threat to migrating juvenile salmonids. 24 refs., 26 figs., 3 tabs

  16. The Importance of Juvenile Root Traits for Crop Yields

    Science.gov (United States)

    White, Philip; Adu, Michael; Broadley, Martin; Brown, Lawrie; Dupuy, Lionel; George, Timothy; Graham, Neil; Hammond, John; Hayden, Rory; Neugebauer, Konrad; Nightingale, Mark; Ramsay, Gavin; Thomas, Catherine; Thompson, Jacqueline; Wishart, Jane; Wright, Gladys

    2014-05-01

    Genetic variation in root system architecture (RSA) is an under-exploited breeding resource. This is partly a consequence of difficulties in the rapid and accurate assessment of subterranean root systems. However, although the characterisation of root systems of large plants in the field are both time-consuming and labour-intensive, high-throughput (HTP) screens of root systems of juvenile plants can be performed in the field, glasshouse or laboratory. It is hypothesised that improving the root systems of juvenile plants can accelerate access to water and essential mineral elements, leading to rapid crop establishment and, consequently, greater yields. This presentation will illustrate how aspects of the juvenile root systems of potato (Solanum tuberosum L.) and oilseed rape (OSR; Brassica napus L.) correlate with crop yields and examine the reasons for such correlations. It will first describe the significant positive relationships between early root system development, phosphorus acquisition, canopy establishment and eventual yield among potato genotypes. It will report the development of a glasshouse assay for root system architecture (RSA) of juvenile potato plants, the correlations between root system architectures measured in the glasshouse and field, and the relationships between aspects of the juvenile root system and crop yields under drought conditions. It will then describe the development of HTP systems for assaying RSA of OSR seedlings, the identification of genetic loci affecting RSA in OSR, the development of mathematical models describing resource acquisition by OSR, and the correlations between root traits recorded in the HTP systems and yields of OSR in the field.

  17. Juvenile hyaline fibromatosis. Radiological diagnosis

    International Nuclear Information System (INIS)

    Fuentes, R.; Sar, V.; Cabrera, J.J.; Diaz, L.; Hernandez, B.; Valeron, P.; Baez, O.; Rodriguez, M.

    1993-01-01

    Juvenile hyaline fibromatosis (JHF) is a rare disorder of unknown etiology, very few cases of which have been reported in the literature. It presents similarities to other fibromatosys, but has its particular radiological features which differentiate it from them. The clinical findings consist of several, slow growing, subcutaneous nodules, flexion contractures of the joints which can lead to disability, gingival hypertrophy and muscular atrophy. The suspected radiological diagnosis is confirmed by electron microscopy study of the nodules, although light microscopy can also reveal suggestive images. Author (9 refs.)

  18. Juvenile eye growth, when completed?

    DEFF Research Database (Denmark)

    Fledelius, Hans C; Christensen, Anders S; Fledelius, Christian

    2014-01-01

    PURPOSE: To test Sorsby's classical statement of axial eye growth as completed at the age of 13 years, with a view also to differentiating between basic eye growth and juvenile elongation associated with eventual refractive change towards myopia. METHODS: (i) A total of 160 healthy eyes close...... about age 13 as general limit found support from the cross-sectional data, which suggested stable emmetropic eye size from about 11-12 years, with an average apparently outgrown male emmetropic value of 23.5 mm versus females' 22.9 mm. The longitudinal data, however, showed emmetropic growth also beyond...

  19. Juvenile ossifying fibroma: Psammamatoid variant

    Directory of Open Access Journals (Sweden)

    Shivani Aggarwal

    2012-01-01

    Full Text Available Juvenile ossifying fibroma is a rare fibro-osseous lesion containing variable amount of calcified masses, which resembles bone or cementum within a fibrocellular connective tissue stroma. It has variable clinical behavior, highly aggressive in nature including invasion and destruction of adjacent anatomic structures with a strong tendency to recur. We reported a 28-year-old female patient with a growth in the upper left vestibule region extending from canine to molar region with clinical, histopathological, and radiological features are presented. Surgical management was done, and regular follow-up was advised.

  20. THE STUDY OF FEATURES OF GUILT OF JUVENILE OFFENDERS IN THE CONTEXT OF JUVENILE JUSTICE

    Directory of Open Access Journals (Sweden)

    Natalija Vladimirovna Galkina

    2015-08-01

    Full Text Available The article is devoted to the results of empirical studies of the experiences of guilt of juvenile offenders in the context of juvenile justice where a minor appears as the subject of legal relations. Restorative approach of juvenile justice is based on an admission of guilt to the victim. In connection with it, the research of features of the guilt of minors who have committed an offence and the conditions for the development of the subjectivity will enhance understanding of the possibilities of restorative juvenile justice system in the prevention of juvenile delinquency.Thus, the results of empirical research presented in the article are important for determining of the psychological bases of realization of rehabilitation programs in the context of juvenile justice. In particular, the results are important for the organization and conduct of psychological work to overcome the psychological barriers in the behavior of juveniles having inherently maladaptive guilt and destructive psychological defense mechanisms.

  1. Juveniles' Motivations for Remaining in Prostitution

    Science.gov (United States)

    Hwang, Shu-Ling; Bedford, Olwen

    2004-01-01

    Qualitative data from in-depth interviews were collected in 1990-1991, 1992, and 2000 with 49 prostituted juveniles remanded to two rehabilitation centers in Taiwan. These data are analyzed to explore Taiwanese prostituted juveniles' feelings about themselves and their work, their motivations for remaining in prostitution, and their difficulties…

  2. Moral development of solo juvenile sex offenders

    NARCIS (Netherlands)

    van Vugt, E.; Stams, G.J.; Dekovic, M.; Brugman, D.; Rutten, E.; Hendriks, J.

    2008-01-01

    This study compared the moral development of solo juvenile male sex offenders (n = 20) and juvenile male non-offenders (n = 76), aged 13-19 years, from lower socioeconomic and educational backgrounds. The Moral Orientation Measure (MOM) was used to assess punishment- and victim-based moral

  3. Juvenile Obesity, Physical Activity, and Lifestyle Changes.

    Science.gov (United States)

    Bar-Or, Oded

    2000-01-01

    Because many obese children become obese adults, the recent rapid increase in juvenile obesity poses a major public health challenge. Enhanced physical activity is a cornerstone in a multidisciplinary approach to preventing and treating juvenile obesity. Giving exercise recommendations focused for obese youth is critical. Cutting down on sedentary…

  4. Using the Juvenile Justice Poster. Teaching Strategy.

    Science.gov (United States)

    Update on Law-Related Education, 2000

    2000-01-01

    Presents a lesson that can help students review and summarize what they have learned about the juvenile justice system. Explains that the students discuss how the juvenile justice system can be improved and conduct a survey on how it might be changed in the future. Provides a copy of the survey and directions. (CMK)

  5. Intelligence Score Profiles of Female Juvenile Offenders

    Science.gov (United States)

    Werner, Shelby Spare; Hart, Kathleen J.; Ficke, Susan L.

    2016-01-01

    Previous studies have found that male juvenile offenders typically obtain low scores on measures of intelligence, often with a pattern of higher scores on measures of nonverbal relative to verbal tasks. The research on the intelligence performance of female juvenile offenders is limited. This study explored the Wechsler Intelligence Scale for…

  6. Reformations in Zimbabwe's juvenile justice system | Ruparanganda ...

    African Journals Online (AJOL)

    Children in conflict with the law are often stigmatized and shunned by society as they are perceived as a threat to society. Historically, Zimbabwe's juvenile justice system has been retributive and focused on punishing the juvenile offender. As a result, it has been criticised from a number of viewpoints, including the need to ...

  7. Samtidskunst og migration

    DEFF Research Database (Denmark)

    Petersen, Anne Ring

    2010-01-01

    "Samtidskunst og migration. En oversigt over faglitteraturen" er en forskningsoversigt der gør status over hvad der hidtil er skrevet inden for det kunsthistoriske område om vor tids billedkunst og migration som politisk, socialt og kulturelt fænomen, primært i forbindelse med immigration til...

  8. The Great Migration.

    Science.gov (United States)

    Trotter, Joe William, Jr.

    2002-01-01

    Describes the migration of African Americans in the United States and the reasons why African Americans migrated from the south. Focuses on issues, such as the effect of World War I, the opportunities offered in the north, and the emergence of a black industrial working class. (CMK)

  9. Migrating Art History

    DEFF Research Database (Denmark)

    Ørum, Tania

    2012-01-01

    Review of Hiroko Ikegami, The Great Migrator. Robert Rauschenberg and the Global Rise of American Art. Cambridge Mass., The MIT Press, 2010. 277 pages. ISBN 978-0-262-01425-0.......Review of Hiroko Ikegami, The Great Migrator. Robert Rauschenberg and the Global Rise of American Art. Cambridge Mass., The MIT Press, 2010. 277 pages. ISBN 978-0-262-01425-0....

  10. Migration, klima og sundhed

    DEFF Research Database (Denmark)

    Tellier, Siri; Carballo, Manuel

    2009-01-01

    Many tentative connections have been postulated between migration and climate. This article points to rural-urban migration, particularly into low elevation urban slums prone to flooding as an issue needing urgent attention by health professionals. It also notes the no-man's land in which environ...

  11. Migration in Burkina Faso

    NARCIS (Netherlands)

    Wouterse, F.S.

    2007-01-01

    Migration plays an important role in development and as a strategy for poverty reduction. A recent World Bank investigation finds a significant positive relationship between international migration and poverty reduction at the country level (Adams and Page 2003). Burkina Faso, whose conditions for

  12. Migration, Narration, Identity

    DEFF Research Database (Denmark)

    Leese, Peter

    (co-editor with Carly McLaughlin and Wladyslaw Witalisz) This book presents articles resulting from joint research on the representations of migration conducted in connection with the Erasmus Intensive Programme entitled «Migration and Narration» taught to groups of international students over...

  13. Spatio-temporal migration patterns of Pacific salmon smolts in rivers and coastal marine waters.

    Directory of Open Access Journals (Sweden)

    Michael C Melnychuk

    Full Text Available BACKGROUND: Migrations allow animals to find food resources, rearing habitats, or mates, but often impose considerable predation risk. Several behavioural strategies may reduce this risk, including faster travel speed and taking routes with shorter total distance. Descriptions of the natural range of variation in migration strategies among individuals and populations is necessary before the ecological consequences of such variation can be established. METHODOLOGY/PRINCIPAL FINDINGS: Movements of tagged juvenile coho, steelhead, sockeye, and Chinook salmon were quantified using a large-scale acoustic tracking array in southern British Columbia, Canada. Smolts from 13 watersheds (49 watershed/species/year combinations were tagged between 2004-2008 and combined into a mixed-effects model analysis of travel speed. During the downstream migration, steelhead were slower on average than other species, possibly related to freshwater residualization. During the migration through the Strait of Georgia, coho were slower than steelhead and sockeye, likely related to some degree of inshore summer residency. Hatchery-reared smolts were slower than wild smolts during the downstream migration, but after ocean entry, average speeds were similar. In small rivers, downstream travel speed increased with body length, but in the larger Fraser River and during the coastal migration, average speed was independent of body length. Smolts leaving rivers located towards the northern end of the Strait of Georgia ecosystem migrated strictly northwards after ocean entry, but those from rivers towards the southern end displayed split-route migration patterns within populations, with some moving southward. CONCLUSIONS/SIGNIFICANCE: Our results reveal a tremendous diversity of behavioural migration strategies used by juvenile salmon, across species, rearing histories, and habitats, as well as within individual populations. During the downstream migration, factors that had strong

  14. The Globalisation of migration

    Directory of Open Access Journals (Sweden)

    Milan Mesić

    2002-04-01

    Full Text Available The paper demonstrates that contemporary international migration is a constitutive part of the globalisation process. After defining the concepts of globalisation and the globalisation of migration, the author discusses six key themes, linking globalisation and international migration (“global cities”, the scale of migration; diversification of migration flows; globalisation of science and education; international migration and citizenship; emigrant communities and new identities. First, in accordance with Saskia Sassen’s analysis, the author rejects the wide-spread notion that unqualified migrants have lost an (important role in »global cities«, i.e. in the centres of the new (global economy. Namely, the post-modern service sector cannot function without the support of a wide range of auxiliary unqualified workers. Second, a critical comparison with traditional overseas mass migration to the USA at the turn of the 19th and 20th centuries indicates that present international migration is, perhaps, less extensive – however it is important to take into consideration various limitations that previously did not exist, and thus the present migration potential is in really greater. Third, globalisation is more evident in a diversification of the forms of migration: the source area of migrants to the New World and Europe has expanded to include new regions in the world; new immigration areas have arisen (the Middle East, new industrial countries of the Far East, South Europe; intra-regional migration has intensified. Forth, globalisation is linked to an increased migration of experts and the pessimistic notion of a brain drain has been replaced by the optimistic idea of a brain gain. Fifth, contemporary international migration has been associated with a crisis of the national model of citizenship. Sixth, the interlinking of (migrant cultural communities regardless of distance and the physical proximity of cultural centres (the

  15. Multi-source least-squares migration of marine data

    KAUST Repository

    Wang, Xin

    2012-11-04

    Kirchhoff based multi-source least-squares migration (MSLSM) is applied to marine streamer data. To suppress the crosstalk noise from the excitation of multiple sources, a dynamic encoding function (including both time-shifts and polarity changes) is applied to the receiver side traces. Results show that the MSLSM images are of better quality than the standard Kirchhoff migration and reverse time migration images; moreover, the migration artifacts are reduced and image resolution is significantly improved. The computational cost of MSLSM is about the same as conventional least-squares migration, but its IO cost is significantly decreased.

  16. Malaysia and forced migration

    Directory of Open Access Journals (Sweden)

    Arzura Idris

    2012-06-01

    Full Text Available This paper analyzes the phenomenon of “forced migration” in Malaysia. It examines the nature of forced migration, the challenges faced by Malaysia, the policy responses and their impact on the country and upon the forced migrants. It considers forced migration as an event hosting multifaceted issues related and relevant to forced migrants and suggests that Malaysia has been preoccupied with the issue of forced migration movements. This is largely seen in various responses invoked from Malaysia due to “south-south forced migration movements.” These responses are, however, inadequate in terms of commitment to the international refugee regime. While Malaysia did respond to economic and migration challenges, the paper asserts that such efforts are futile if she ignores issues critical to forced migrants.

  17. Seasonal growth and mortality of juveniles of Lampsilis fasciola (Bivalvia: Unionidae) released to a fish hatchery raceway

    Science.gov (United States)

    Hanlon, Shane D.; Neves, Richard J.

    2006-01-01

    Recent efforts to restore remnant or extirpated populations of freshwater mussels have focused on artificial propagation as an effective and practical conservation strategy. Although artificially cultured juveniles have been produced and released to the wild at various times of the year, no study has investigated the best time of year to release these juveniles. Newly metamorphosed juveniles of the wavyrayed lampmussel (Lampsilis fasciola) were released into a stream-fed fish hatchery raceway during March, June, and September. Growth and survival rates were measured 32, 52, 72, and 92 days post-metamorphosis. Juveniles released in June experienced the greatest growth and survival rates. Juveniles released in September and March experienced high mortality within the first month of release and exhibited poor growth in the cool water conditions typical of those seasons. Overwinter survival exhibited a size-dependent relationship.

  18. Ecology of Juvenile Salmon in Shallow Tidal Freshwater Habitats in the Vicinity of the Sandy River Delta, Lower Columbia River, 2008 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Sather, NK; Johnson, GE; Storch, AJ [Pacific Northwest National Laboratory

    2009-07-06

    River delta. (2) Characterize the fish community and juvenile salmon migration, including species composition, length-frequency distribution, density (number/m{sup 2}), and temporal and spatial distributions in the vicinity of the Sandy River delta in the lower Columbia River and estuary (LCRE). (3) Determine the stock of origin for juvenile Chinook salmon (Oncorhynchus tshawytscha) captured at sampling sites through genetic identification. (4) Characterize the diets of juvenile Chinook and coho (O. kisutch) salmon captured within the study area. (5) Estimate run timing, residence times, and migration pathways for acoustic-tagged fish in the study area. (6) Conduct a baseline evaluation of the potential restoration to reconnect the old Sandy River channel with the delta. (7) Apply fish density data to initiate a design for a juvenile salmon monitoring program for beach habitats within the tidal freshwater segment of the LCRE (river kilometer 56-234).

  19. Do juveniles bully more than young offenders?

    Science.gov (United States)

    Ireland, Jane L

    2002-04-01

    This study compares bullying behaviour among juvenile and young offenders and incorporates two different methods to measure bullying. Ninety-five male juvenile and 196 male young offenders completed two questionnaires, one that measured bullying directly and one that measured behaviours indicative of "being bullied" or of "bullying others". Juveniles perceived a higher extent of bullying than young offenders. Juveniles reported significantly more physical, psychological or verbal and overall direct forms of bullying behaviour than young offenders. A number of differences were found between juveniles and young offenders with regard to the types of prisoners likely to become victims, who they would advise a victim to speak to and how bullying could be prevented. The results are discussed in relation to developmental theories of aggression and how bullying behaviour can be defined and measured among prisoners. Copyright 2002 The Association for Professionals in Services for Adolescents. Published by Elsevier Science Ltd. All rights reserved.

  20. Juvenile Gaucher disease simulating osteomyelitis

    International Nuclear Information System (INIS)

    Miller, J.H.; Ortega, J.A.; Heisel, M.A.

    1981-01-01

    A case in which several imaging procedures suggested juvenile Gaucher disease in a child who presented with symptomatology of osteomyelitis is discussed. The 20-month girl was given a Technetium-99m radionuclide skeletal examination which revealed intense uptake of tracer agents along the shaft of the right femur. It was also found that the liver and spleen were dramatically Ga-67 avid. The bone pain symptomatology suggested an osteomyelitis of the femur, but skeletal scintigraphy with Tc-99m-labeled bone tracer demonstrated photopenic areas involving the femur, suggesting that the bone pain may have been due to marrow packed with Gaucher cells. This overexpansion of the marrow may lead to microfractures with remodeling seen radiographically as periosteal new bone and scintigraphically as increased periosteal deposition of tracer agent. The radiogallium study was useful to exclude an underlying osteomyelitis in the involved femurs. Although juvenile Gaucher disease is unusual, it should be considered in any child who presents with the constellation of hepatosplenomegaly and bone pain simulating osteomyelitis

  1. Juvenile Gaucher disease simulating osteomyelitis

    Energy Technology Data Exchange (ETDEWEB)

    Miller, J.H.; Ortega, J.A.; Heisel, M.A.

    1981-10-01

    A case in which several imaging procedures suggested juvenile Gaucher disease in a child who presented with symptomatology of osteomyelitis is discussed. The 20-month girl was given a Technetium-99m radionuclide skeletal examination which revealed intense uptake of tracer agents along the shaft of the right femur. It was also found that the liver and spleen were dramatically Ga-67 avid. The bone pain symptomatology suggested an osteomyelitis of the femur, but skeletal scintigraphy with Tc-99m-labeled bone tracer demonstrated photopenic areas involving the femur, suggesting that the bone pain may have been due to marrow packed with Gaucher cells. This overexpansion of the marrow may lead to microfractures with remodeling seen radiographically as periosteal new bone and scintigraphically as increased periosteal deposition of tracer agent. The radiogallium study was useful to exclude an underlying osteomyelitis in the involved femurs. Although juvenile Gaucher disease is unusual, it should be considered in any child who presents with the constellation of hepatosplenomegaly and bone pain simulating osteomyelitis.

  2. Atherosclerosis in Juvenile Idiopathic Arthritis

    Directory of Open Access Journals (Sweden)

    Ewa Jednacz

    2012-01-01

    Full Text Available Atherosclerosis is a chronic inflammatory disease of the arteries. Clinical consequences of the atherosclerotic process occur in the adult population, however atherosclerotic process begins in childhood. The classic risk factors for atherosclerosis include obesity, dyslipidaemia, age, gender or family history. In recent years, attention has been drawn to the similarity between atherosclerotic inflammatory processes and inflammatory changes in the course of systemic connective tissue disease, in particular systemic lupus etythematosus (SLE or rheumatoid arthritis (RA. There is also observed the similarity of the pathogenetic background of development of atherosclerosis and juvenile idiopathic arthritis (JIA. Elevated levels of pro-inflammatory cytokines are observed in the course of juvenile idiopathic arthritis. Also homocysteine concentrations, which may play a significant role in the development of atherosclerotic lesions, are observed higher in patients with JIA. Some studies revealed higher carotid intima-media thickness (IMT index values in children with JIA. In view of the fact that atherosclerotic process begins as early as in childhood, the introduction of appropriate preventive measures in children is a matter of utmost importance.

  3. Domestic and International Climate Migration from Rural Mexico.

    Science.gov (United States)

    Nawrotzki, Raphael J; Runfola, Daniel M; Hunter, Lori M; Riosmena, Fernando

    2016-12-01

    Evidence is increasing that climate change and variability may influence human migration patterns. However, there is less agreement regarding the type of migration streams most strongly impacted. This study tests whether climate change more strongly impacted international compared to domestic migration from rural Mexico during 1986-99. We employ eight temperature and precipitation-based climate change indices linked to detailed migration histories obtained from the Mexican Migration Project. Results from multilevel discrete-time event-history models challenge the assumption that climate-related migration will be predominantly short distance and domestic, but instead show that climate change more strongly impacted international moves from rural Mexico. The stronger climate impact on international migration may be explained by the self-insurance function of international migration, the presence of strong migrant networks, and climate-related changes in wage difference. While a warming in temperature increased international outmigration, higher levels of precipitation declined the odds of an international move.

  4. Domestic and International Climate Migration from Rural Mexico

    Science.gov (United States)

    Nawrotzki, Raphael J.; Runfola, Daniel M.; Hunter, Lori M.; Riosmena, Fernando

    2016-01-01

    Evidence is increasing that climate change and variability may influence human migration patterns. However, there is less agreement regarding the type of migration streams most strongly impacted. This study tests whether climate change more strongly impacted international compared to domestic migration from rural Mexico during 1986-99. We employ eight temperature and precipitation-based climate change indices linked to detailed migration histories obtained from the Mexican Migration Project. Results from multilevel discrete-time event-history models challenge the assumption that climate-related migration will be predominantly short distance and domestic, but instead show that climate change more strongly impacted international moves from rural Mexico. The stronger climate impact on international migration may be explained by the self-insurance function of international migration, the presence of strong migrant networks, and climate-related changes in wage difference. While a warming in temperature increased international outmigration, higher levels of precipitation declined the odds of an international move. PMID:28439146

  5. Donor life stage influences juvenile American eel Anguilla rostrata attraction to conspecific chemical cues

    Science.gov (United States)

    Galbraith, Heather S.; Blakeslee, Carrie J.; Schmucker, Andrew K.; Johnson, Nicholas; Hansen, Michael J.; Li, Weiming

    2017-01-01

    The present study investigated the potential role of conspecific chemical cues in inland juvenile American eel Anguilla rostrata migrations by assessing glass eel and 1 year old elver affinities to elver washings, and elver affinity to adult yellow eel washings. In two-choice maze assays, glass eels were attracted to elver washings, but elvers were neither attracted to nor repulsed by multiple concentrations of elver washings or to yellow eel washings. These results suggest that A. rostrata responses to chemical cues may be life-stage dependent and that glass eels moving inland may use the odour of the previous year class as information to guide migration. The role of chemical cues and olfaction in eel migrations warrants further investigation as a potential restoration tool.

  6. Juvenile Nasophryngeal Angiofibroma,New Aspects in Management

    Directory of Open Access Journals (Sweden)

    Mojtaba Mohammadi Ardehali

    2011-03-01

    Full Text Available Juvenile nasopharyngeal angiofibroma (JNA is a rare, benign and locally invasive tumor. Massive bleeding because of vascularity of tumor and postoperative recurrence are potential problems of management. Endonasal approach reduces the rate of postoperative recurrence, intraoperative bleeding, and complications of surgery, time of operation and duration of hospitalization. In this article, we review the indications and contraindications of endoscopic surgery, indications of radiotherapy in treatment of JNA and our policy in postoperative follow-up and management of patients.

  7. Criteria for sustainable fisheries on juveniles illustrated for Mediterranean hake: control the juvenile harvest, and safeguard spawning refugia to rebuild population fecundity

    Directory of Open Access Journals (Sweden)

    John F. Caddy

    2015-09-01

    Full Text Available The paper provides a broad overview of issues relevant to management of fisheries for juvenile fish in contrast to the many stock assessments following Beverton and Holt’s (1957 approach for rational exploitation of mature fishes. A perspective on assessing these fisheries is illustrated for juvenile European hake, Merluccius merluccius, in the northwestern Mediterranean. Here, a constant natural mortality (M assumption is incorrect, as is the assumption that high fecundities are necessarily adequate for stock replacement. The high Ms-at-age for juveniles generated by the reciprocal model are shown to be a logical counterpart to the high fecundity of hake. Charnov’s criterion of intergenerational reproductive replacement is used to test for a sustainable population, analogous to a limit reference point warning of the dangers of overfishing beyond population replacement. Once peak mortality rates of age 2 hake exceed F(2=1.1-1.2, which is currently the case, reproductive replacement may be at risk. Adult exploitation by inshore trawls is low, and maturing hake surviving the fine-mesh trawl fishery migrate offshore with a reduced vulnerability to fine-mesh gears. Early research suggested that rough bottom near the shelf edge once formed a refugium protecting offshore spawners from trawling, and led to abundant recruitment of juveniles nearer shore. It may not do so if offshore fishing effort by reinforced bottom trawls, gill nets and longlines is uncontrolled. Restoring offshore refugia to protect spawners and controlling peak fishing mortality of juveniles would be a precautionary strategy aimed at restoring previous levels of recruitment to the small-mesh trawl fishery.

  8. Rates of consumption of juvenile salmonids and alternative prey fish by northern squawfish, walleyes, smallmouth bass, and channel catfish in John Day Reservoir, Columbia River

    International Nuclear Information System (INIS)

    Vigg, S.; Poe, T.P.; Prendergast, L.A.; Hansel, H.C.

    1991-01-01

    Adult northern squawfish Ptychocheilus oregonesis, walleyes Stizostedion vitreum, smallmouth bass Micropterus dolomieu, and channel catfish Ictalurus punctatus were sampled from four regions of John Day Reservoir from April to August 1983-1986 to quantify their consumption of 13 species of prey fish, particularly seaward-migrating juvenile Pacific salmon and steelhead (Oncorhynchus spp.). Consumption rates were estimated from field data on stomach contents and digestion rate relations determined in previous investigations. For each predator, consumption rates varied by reservoir area, month, time of day, and predator size or age. The greatest daily consumption of salmonids by northern squawfish and channel catfish occurred in the upper end of the reservoir below McNary Dam. Greatest daily predation by walleyes and smallmouth bass occurred in the middle and lower reservoir. Consumption rates of all predators were highest in July, concurrent with maximum temperature and abundance of juvenile salmonids. Feeding by the predators tended to peak after dawn and near midnight. Northern squawfish below McNary Dam exhibited this pattern, but fed mainly in the morning hours down-reservoir. The daily ration of total prey fish was highest for northern squawfish over 451 mm fork length, for walleyes 201-250 mm, for smallmouth bass 176-200 mm, and for channel catfish 401-450 mm. Averaged over all predator sizes and sampling months (April-August), the total daily ration (fish plus other prey) of smallmouth bass was about twice that of channel catfish, northern squawfish, and walleyes. However, northern squawfish was clearly the major predator on juvenile salmonids

  9. Survival and Passage of Juvenile Chinook Salmon and Steelhead Passing through Bonneville Dam, 2010

    Energy Technology Data Exchange (ETDEWEB)

    Ploskey, Gene R.; Weiland, Mark A.; Hughes, James S.; Woodley, Christa M.; Deng, Zhiqun; Carlson, Thomas J.; Kim, Jin A.; Royer, Ida M.; Batten, George W.; Cushing, Aaron W.; Carpenter, Scott M.; Etherington, D. J.; Faber, Derrek M.; Fischer, Eric S.; Fu, Tao; Hennen, Matthew J.; Mitchell, Tyler; Monter, Tyrell J.; Skalski, John R.; Townsend, Richard L.; Zimmerman, Shon A.

    2011-12-01

    Pacific Northwest National Laboratory (PNNL) and subcontractors conducted an acoustic-telemetry study of juvenile salmonid fish passage and survival at Bonneville Dam in 2010. The study was conducted to assess the readiness of the monitoring system for official compliance studies under the 2008 Biological Opinion and Fish Accords and to assess performance measures including route-specific fish passage proportions, travel times, and survival based upon a single-release model. This also was the last year of evaluation of effects of a behavioral guidance device installed in the Powerhouse 2 forebay. The study relied on releases of live Juvenile Salmon Acoustic Telemetry System tagged smolts in the Columbia River and used acoustic telemetry to evaluate the approach, passage, and survival of passing juvenile salmon. This study supports the U.S. Army Corps of Engineers continual effort to improve conditions for juvenile anadromous fish passing through Columbia River dams.

  10. Survival and Passage of Juvenile Chinook Salmon and Steelhead Passing Through Bonneville Dam, 2010

    Energy Technology Data Exchange (ETDEWEB)

    Ploskey, Gene R.; Weiland, Mark A.; Hughes, James S.; Woodley, Christa M.; Deng, Zhiqun; Carlson, Thomas J.; Kim, Jin A.; Royer, Ida M.; Batten, George W.; Cushing, Aaron W.; Carpenter, Scott M.; Etherington, D. J.; Faber, Derrek M.; Fischer, Eric S.; Fu, Tao; Hennen, Matthew J.; Mitchell, T. D.; Monter, Tyrell J.; Skalski, J. R.; Townsend, Richard L.; Zimmerman, Shon A.

    2012-09-01

    Pacific Northwest National Laboratory (PNNL) and subcontractors conducted an acoustic-telemetry study of juvenile salmonid fish passage and survival at Bonneville Dam in 2010. The study was conducted to assess the readiness of the monitoring system for official compliance studies under the 2008 Biological Opinion and Fish Accords and to assess performance measures including route-specific fish passage proportions, travel times, and survival based upon a single-release model. This also was the last year of evaluation of effects of a behavioral guidance device installed in the Powerhouse 2 forebay. The study relied on releases of live Juvenile Salmon Acoustic Telemetry System tagged smolts in the Columbia River and used acoustic telemetry to evaluate the approach, passage, and survival of passing juvenile salmon. This study supports the U.S. Army Corps of Engineers continual effort to improve conditions for juvenile anadromous fish passing through Columbia River dams.

  11. Survival and Passage of Juvenile Chinook Salmon and Steelhead Passing through Bonneville Dam, 2011

    Energy Technology Data Exchange (ETDEWEB)

    Ploskey, Gene R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Batten, G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cushing, Aaron W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kim, Jin A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Johnson, Gary E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Skalski, J. R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Townsend, Richard L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Seaburg, Adam [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Weiland, Mark A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Woodley, Christa M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hughes, James S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Carlson, Thomas J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Carpenter, Scott M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Deng, Zhiqun [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Etherington, D. J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fischer, Eric S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fu, Tao [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Greiner, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hennen, Matthew J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Martinez, Jayson J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mitchell, T. D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rayamajhi, Bishes [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zimmerman, Shon A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2013-02-15

    Pacific Northwest National Laboratory (PNNL) and subcontractors conducted an acoustic-telemetry study of juvenile salmonid fish passage and survival at Bonneville Dam in 2011. The study was conducted to assess the readiness of the monitoring system for official compliance studies under the 2008 Biological Opinion and Fish Accords and to assess performance measures including route-specific fish passage proportions, travel times, and survival based upon a virtual/paired-release model. The study relied on releases of live Juvenile Salmon Acoustic Telemetry System tagged smolts in the Columbia River and used acoustic telemetry to evaluate the approach, passage, and survival of passing juvenile salmon using a virtual release, paired reference release survival model. This study supports the U.S. Army Corps of Engineers’ continual effort to improve conditions for juvenile anadromous fish passing through Columbia River dams.

  12. Final Report: Migration Mechanisms for Large-scale Parallel Applications

    Energy Technology Data Exchange (ETDEWEB)

    Jason Nieh

    2009-10-30

    Process migration is the ability to transfer a process from one machine to another. It is a useful facility in distributed computing environments, especially as computing devices become more pervasive and Internet access becomes more ubiquitous. The potential benefits of process migration, among others, are fault resilience by migrating processes off of faulty hosts, data access locality by migrating processes closer to the data, better system response time by migrating processes closer to users, dynamic load balancing by migrating processes to less loaded hosts, and improved service availability and administration by migrating processes before host maintenance so that applications can continue to run with minimal downtime. Although process migration provides substantial potential benefits and many approaches have been considered, achieving transparent process migration functionality has been difficult in practice. To address this problem, our work has designed, implemented, and evaluated new and powerful transparent process checkpoint-restart and migration mechanisms for desktop, server, and parallel applications that operate across heterogeneous cluster and mobile computing environments. A key aspect of this work has been to introduce lightweight operating system virtualization to provide processes with private, virtual namespaces that decouple and isolate processes from dependencies on the host operating system instance. This decoupling enables processes to be transparently checkpointed and migrated without modifying, recompiling, or relinking applications or the operating system. Building on this lightweight operating system virtualization approach, we have developed novel technologies that enable (1) coordinated, consistent checkpoint-restart and migration of multiple processes, (2) fast checkpointing of process and file system state to enable restart of multiple parallel execution environments and time travel, (3) process migration across heterogeneous

  13. Migration and AIDS.

    Science.gov (United States)

    1998-01-01

    This article presents the perspectives of UNAIDS and the International Organization for Migration (IOM) on migration and HIV/AIDS. It identifies research and action priorities and policy issues, and describes the current situation in major regions of the world. Migration is a process. Movement is enhanced by air transport, rising international trade, deregulation of trade practices, and opening of borders. Movements are restricted by laws and statutes. Denial to freely circulate and obtain asylum is associated with vulnerability to HIV infections. A UNAIDS policy paper in 1997 and IOM policy guidelines in 1988 affirm that refugees and asylum seekers should not be targeted for special measures due to HIV/AIDS. There is an urgent need to provide primary health services for migrants, voluntary counseling and testing, and more favorable conditions. Research is needed on the role of migration in the spread of HIV, the extent of migration, availability of health services, and options for HIV prevention. Research must be action-oriented and focused on vulnerability to HIV and risk taking behavior. There is substantial mobility in West and Central Africa, economic migration in South Africa, and nonvoluntary migration in Angola. Sex workers in southeast Asia contribute to the spread. The breakup of the USSR led to population shifts. Migrants in Central America and Mexico move north to the US where HIV prevalence is higher.

  14. Nanoparticles migration in fractured rocks and affects on contaminant migration

    Science.gov (United States)

    Missana, Tiziana; Garcia-Gutierrez, Miguel; Alonso, Ursula

    2014-05-01

    In previous studies, the transport behavior of artificial (gold and latex) and natural (smectite clay) colloids, within a planar fracture in crystalline rock, was analyzed. In order to better understand the effects of colloid size, shape and surface charge on nanoparticle migration and especially on filtration processes on natural rock surfaces, different clay colloids and oxide nanoparticles were selected and their transport studied as a function of the residence time. In all the cases, (a fraction of) the nanoparticles travelled in the fracture as fast as or faster than water (with a retardation factor, Rf ≤ 1) and the observed Rf, was related to the Taylor dispersion coefficient, accounting for colloid size, water velocity and fracture width. However, under most of the cases, in contrast to the behavior of a conservative tracer, colloids recovery was much lower than 100 %. Differences in recovery between different nanoparticles, under similar residence times, were analyzed. In order to evaluate the possible consequences, on contaminant migration, of the presence of nanoparticles in the system, transport tests were carried out with both colloids and sorbing radionuclides. The overall capacity for colloids of enhancing radionuclide migration in crystalline rock fractures is discussed. Acknowledgments: The research leading to these results received funding from EU FP7/2007-2011 grant agreement Nº 295487 (BELBAR, Bentonite Erosion: effects on the Long term performance of the engineered Barrier and Radionuclide Transport) and by the Spanish Government under the project NANOBAG (CTM2011-2797).

  15. Angiofibroma juvenil nasofaríngeo Juvenile nasopharyngeal angiofibroma

    Directory of Open Access Journals (Sweden)

    Juan Gualberto Lescaille Torres

    2012-06-01

    Full Text Available Se presenta el caso de un angiofibroma juvenil nasofaríngeo, en un paciente del consultorio médico No. 9, que pertenece al Policlínico Integral Docente "Carlos Manuel Portuondo" de Marianao. Se reconoce la importancia de realizar una historia clínica detallada, así como un minucioso examen físico, por el médico de familia y el otorrinolaringólogo del área de salud, que incluyó la rinoscopia posterior, para poder llegar al diagnóstico de esa patología, y realizar la extirpación precoz del angiofibroma, mediante el proceder quirúrgico. Se concluyó que el diagnóstico clínico se correspondió con el histopatológico, y que la conducta quirúrgica temprana es resolutiva en la afección.It is presented a case of juvenile nasopharyngeal angiofibroma in a patient with this pathology, from the clicial practice No. 9, in Comprehensive Teaching Polyclinic "Carlos Manuel Portuondo" in Marianao. It recognizes the importance of a thorough clinical history and careful physical examination by the family physician and the otolaryngologist in this health area, including a posterior rhinoscopy, to diagnose this disease and to achieve early removal of the angiofibroma, by a surgical procedure. It was concluded that the clinical diagnosis corresponded to the histopathological diagnosis, and that early surgical treatment is resolute in this condition.

  16. Migration and risk: net migration in marginal ecosystems and hazardous areas

    International Nuclear Information System (INIS)

    De Sherbinin, Alex; Levy, Marc; Adamo, Susana; MacManus, Kytt; Yetman, Greg; Mara, Valentina; Razafindrazay, Liana; Aichele, Cody; Pistolesi, Linda; Goodrich, Benjamin; Srebotnjak, Tanja

    2012-01-01

    The potential for altered ecosystems and extreme weather events in the context of climate change has raised questions concerning the role that migration plays in either increasing or reducing risks to society. Using modeled data on net migration over three decades from 1970 to 2000, we identify sensitive ecosystems and regions at high risk of climate hazards that have seen high levels of net in-migration and out-migration over the time period. This paper provides a literature review on migration related to ecosystems, briefly describes the methodology used to develop the estimates of net migration, then uses those data to describe the patterns of net migration for various ecosystems and high risk regions. The study finds that negative net migration generally occurs over large areas, reflecting its largely rural character, whereas areas of positive net migration are typically smaller, reflecting its largely urban character. The countries with largest population such as China and India tend to drive global results for all the ecosystems found in those countries. Results suggest that from 1970 to 2000, migrants in developing countries have tended to move out of marginal dryland and mountain ecosystems and out of drought-prone areas, and have moved towards coastal ecosystems and areas that are prone to floods and cyclones. For North America results are reversed for dryland and mountain ecosystems, which saw large net influxes of population in the period of record. Uncertainties and potential sources of error in these estimates are addressed. (letter)

  17. Labor migration in Asia.

    Science.gov (United States)

    Martin, P L

    1991-01-01

    "A recent conference sponsored by the United Nations Center for Regional Development (UNCRD) in Nagoya, Japan examined the growing importance of labor migration for four major Asian labor importers (Japan, Hong Kong, Malaysia, and Singapore) and five major labor exporters (Bangladesh, Korea, Pakistan, Philippines, and Thailand).... The conference concluded that international labor migration would increase within Asia because the tight labor markets and rising wages which have stimulated Japanese investment in other Asian nations, for example, have not been sufficient to eliminate migration push and pull forces...." excerpt

  18. Improved intake design for downstream migrating fish at hydropower plants

    International Nuclear Information System (INIS)

    Mih, W.C.

    1991-01-01

    This paper reports on hydroelectric power projects on the Columbia River which provided low-cost electricity to the Pacific Northwest. However, they are detrimental to anadromous fisheries resources. Anadromous fish are migratory. They begin their life in shallow mountain streams. After several months, they migrate to the ocean, where the fish grow to maturity before their return migration. Remarkably, most anadromous fish return to spawn in their natal streams. At dams, the upstream migration of grown salmon and steelhead is accomplished through fishways. The downstream migration of juveniles remains a serious problem. Juvenile fish follow the water flow during their sea-ward migration. When passing through a turbine, fish can be severely injured due to the sudden pressure drop, high velocity shear zones, and rotating turbine blades. Stunned fish that survive the gauntlet of the turbine are easy prey for sea gulls and squawfish in the tailrace of the powerhouse. Fish mortality per turbine passage is estimated at 15 percent. With nine hydropower projected on the main steam of the Columbia River, their combined mortality is very serious. The historical Columbia River anadromous run of about 12 million fish has declined to 2.5 million in recent years. Modern high-output hydraulic turbines are designed to be placed at a lower elevation to minimize cavitation damage to turbine blades. The modern design trend of deep intake submergence has caused parallel and unsteady vortex flow patterns in the forebay, resulting in a decrease in the guiding efficiency of the screens, such as at Bonneville Second Powerhouse and at Rocky Reach Project

  19. Predation by northern squawfish on live and dead juvenile chinook salmon

    International Nuclear Information System (INIS)

    Gadomski, D.M.; Hall-Griswold, J.A.

    1992-01-01

    Northern squawfish Ptychocheilus oregonensis is a major predator of juvenile salmonids Oncorhynchus spp. migrating downstream through the Columbia River. High predation rates occur just below dams. If northern squawfish selectively consume salmonids killed or injured during dam passage, previous estimates of predation mortality may be too high. We conducted laboratory experiments that indicate northern squawfish prefer dead juvenile chinook salmon O. tshawytscha over live individuals. When equal numbers of dead and live chinook salmon were offered to northern squawfish maintained on a natural photoperiod (15 h light: 9 h darkness), significantly more (P < 0.05) dead than live fish were consumed, both in 1,400-L circular tanks and in an 11,300-L raceway (62% and 79% of prey consumed were dead, respectively). When dead and live juvenile chinook salmon were provided in proportions more similar to those below dams (20% dead, 80% live), northern squawfish still selected for dead prey (36% of fish consumed were dead). In additional experiments, northern squawfish were offered a proportion of 20% dead juvenile chinook salmon during 4-h periods of either light or darkness. The predators were much more selective for dead chinook salmon during bright light (88% of fish consumed were dead) than during darkness (31% were dead)

  20. Monitoring the Migrations of Wild Snake River Spring/Summer Chinook Salmon Smolts, 2002-2003 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Achord, Stephen; McNatt, Regan A.; Hockersmith, Eric E. (National Marine Fisheries Service, Northwest Fisheries Science Center, Fish Ecology Division, Seattle, WA)

    2004-04-01

    Prior to 1992, decisions on dam operations and use of stored water relied on recoveries of branded hatchery fish, index counts at traps and dams, and flow patterns at the dams. The advent of PIT-tag technology provided the opportunity to precisely track the smolt migrations of many wild stocks as they pass through the hydroelectric complex and other monitoring sites on their way to the ocean. With the availability of the PIT tag, a more complete approach to these decisions was undertaken starting in 1992 with the addition of PIT-tag detections of several wild spring and summer chinook salmon stocks at Lower Granite Dam. Using data from these detections, we initiated development of a database on wild fish, addressing several goals of the Columbia River Basin Fish and Wildlife Program of the Pacific Northwest Electric Power Planning Council and Conservation Act (NPPC 1980). Section 304(d) of the program states, ''The monitoring program will provide information on the migrational characteristics of the various stocks of salmon and steelhead within the Columbia Basin.'' Further, Section 201(b) urges conservation of genetic diversity, which will be possible only if wild stocks are preserved. Section 5.9A.1 of the 1994 Fish and Wildlife Program states that field monitoring of smolt movement will be used to determine the best timing for water storage releases and Section 5.8A.8 states that continued research is needed on survival of juvenile wild fish before they reach the first dam with special attention to water quantity, quality, and several other factors. The goals of this ongoing study are as follows (1) Characterize the migration timing and estimate parr-to-smolt survival of different stocks of wild Snake River spring/summer chinook salmon smolts at Lower Granite Dam. (2) Determine whether consistent migration patterns are apparent. (3) Determine what environmental factors influence these patterns. (4) Characterize the migrational behavior and

  1. Vegetative propagation of mature and juvenile northern red oak

    Science.gov (United States)

    James J. Zaczek; K. C. Steiner; C. W., Jr. Heuser

    1993-01-01

    Rooting trials were established to evaluate rooting success of cuttings from mature and juvenile, grafted and ungrafted northern red oak (NRO). Buds from 4 mature NRO ortets and juvenile seedlings were grafted onto juvenile and mature rootstock. Cuttings were collected from the grafts and from juvenile and mature shoots developed in situ and...

  2. Identification of non-volatile compounds and their migration from hot melt adhesives used in food packaging materials characterized by ultra-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry.

    Science.gov (United States)

    Vera, Paula; Canellas, Elena; Nerín, Cristina

    2013-05-01

    The identification of unknown non-volatile migrant compounds from adhesives used in food contact materials is a very challenging task because of the number of possible compounds involved, given that adhesives are complex mixtures of chemicals. The use of ultra-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC-MS/QTOF) is shown to be a successful tool for identifying non-targeted migrant compounds from two hot melt adhesives used in food packaging laminates. Out of the seven migrants identified and quantified, five were amides and one was a compound classified in Class II of the Cramer toxicity. None of the migration values exceeded the recommended Cramer exposure values.

  3. Spatial and temporal variability in the trans-Pacific migration of Pacific bluefin tuna (Thunnus orientalis) revealed by archival tags

    Science.gov (United States)

    Fujioka, Ko; Fukuda, Hiromu; Tei, Yaoki; Okamoto, Suguru; Kiyofuji, Hidetada; Furukawa, Seishiro; Takagi, Junichi; Estess, Ethan; Farwell, Charles J.; Fuller, Daniel W.; Suzuki, Nobuaki; Ohshimo, Seiji; Kitagawa, Takashi

    2018-03-01

    Archival electronic tags were internally implanted in 713 age-0 Pacific bluefin tuna (PBF) caught in their nursery waters off the southern coast of Japan and in the East China Sea over an extended study period (1995-2015) to clarify the spatial and temporal variability of their trans-Pacific migration. Two hundred twenty-five of these tagged tuna were recaptured by fisheries (31.6%), and we successfully retrieved tag data from 14 of 21 individuals recovered in the Eastern pacific. Furthermore, one archival tag recovered in the Western Pacific revealed that the individual had performed a trans-Pacific migration, so in total 21 tagged PBF were shown to have migrated to the Eastern Pacific (2.9% of the total tags released). We successfully downloaded data from 15 of these 21 archival tags, which revealed that some age-1 PBF migrate rapidly (123.9 ± 82.8 km day-1) and directly from waters offshore of Japan to the eastern Pacific (160.0°E to 130.0°W), a journey that takes an average of 2.5 months (ranging from 1.2 to 5.5 months) through relatively cool waters (14.7 ± 2.0 °C). All juvenile PBF began their trans-Pacific migration shortly after exposure to cooler water temperatures (physiological challenge for this age class. Three patterns were identified in the timing of the departure of juvenile PBF from the western Pacific: departing 12-14 months post-hatch (N = 7) in early summer (May-July), departing 17-19 months post-hatch (N = 7) in late autumn (October-December), and departing 21 months post-hatch (N = 1) in late winter (February). The PBF tagged along the southern coast of Japan (SCJ) arrived in the eastern Pacific earlier than those tagged in the East China Sea (ECS), most likely due to the shorter travel distance. Additionally, the PBF that began their trans-Pacific migration in the earlier period remained in an offshore foraging zone (the Kuroshio-Oyashio transition region) for shorter periods (2.8 months on average) and at lower latitudes (35.0

  4. Occupational change, employer change, internal migration, and earnings.

    Science.gov (United States)

    Krieg, R G

    1997-02-01

    "In this paper I use microdata from the [U.S.] Panel Study of Income Dynamics to measure the financial returns to intercounty and interstate migration for individuals in a temporal framework accounting for gains that accrue over time.... To account for the indirect effects of migration on earnings, explanatory variables are created by interacting migration status with: (1) occupational change, (2) employer change and (3) changes in both occupation and employer. These interaction terms are then included in the earnings functions. Earnings are estimated for three years subsequent to the migration decision to account for the financial returns to migration accruing over time. Results indicate that, when estimating earnings, the use of a simple migration dummy variable will mask the indirect effects of migration on earnings." excerpt

  5. Does Migration Influence Regional Growth in Romania?

    OpenAIRE

    Bunea Daniela

    2011-01-01

    In the European framework, regional convergence is crucial in ensuring European integration. “Sigma-convergence” deals with how the distribution of national output across economies evolves over time whereas “beta-convergence” deals with the mobility of this output within the same distribution. Migration is one important mechanism in generating convergence. In Romania, during the last few years, the main results point out at an income divergence trend with no migration influence. This irreleva...

  6. Multicore Considerations for Legacy Flight Software Migration

    Science.gov (United States)

    Vines, Kenneth; Day, Len

    2013-01-01

    In this paper we will discuss potential benefits and pitfalls when considering a migration from an existing single core code base to a multicore processor implementation. The results of this study present options that should be considered before migrating fault managers, device handlers and tasks with time-constrained requirements to a multicore flight software environment. Possible future multicore test bed demonstrations are also discussed.

  7. Juvenile fibromyalgia syndrome. Interdisciplinary treatment

    Directory of Open Access Journals (Sweden)

    Hanna Siuchnińska

    2014-11-01

    Full Text Available Fibromyalgia syndrome (FM belongs to soft tissue pain syndromes of unknown cause, also referred to as “soft tissue rheumatism”. It is characterized by chronic widespread pain as well as additional symptoms such as fatigue, sleep and mood disturbance and cognitive problems. There is more and more data showing that this condition may start at a young age or even in childhood, adversely affecting development processes and resulting in dysfunctional social and family relationships. Because of the multifaceted character of fibromyalgia the efficient treatment of this disorder can be difficult and requires comprehensive care. This work reviews most recommended procedures used in integrated treatment programmes for juvenile fibromyalgia syndrome (JFM.

  8. [Physiotherapy for juvenile idiopathic arthritis].

    Science.gov (United States)

    Spamer, M; Georgi, M; Häfner, R; Händel, H; König, M; Haas, J-P

    2012-07-01

    Control of disease activity and recovery of function are major issues in the treatment of children and adolescents suffering from juvenile idiopathic arthritis (JIA). Functional therapies including physiotherapy are important components in the multidisciplinary teamwork and each phase of the disease requires different strategies. While in the active phase of the disease pain alleviation is the main focus, the inactive phase requires strategies for improving motility and function. During remission the aim is to regain general fitness by sports activities. These phase adapted strategies must be individually designed and usually require a combination of different measures including physiotherapy, occupational therapy, massage as well as other physical procedures and sport therapy. There are only few controlled studies investigating the effectiveness of physical therapies in JIA and many strategies are derived from long-standing experience. New results from physiology and sport sciences have contributed to the development in recent years. This report summarizes the basics and main strategies of physical therapy in JIA.

  9. Physicists' Forced Migrations under Hitler

    Science.gov (United States)

    Beyerchen, Alan

    2011-03-01

    When the Nazis came to power in early 1933 they initiated formal and informal measures that forced Jews and political opponents from public institutions such as universities. Some physicists retired and others went into industry, but most emigrated. International communication and contact made emigration a viable option despite the desperate economic times in the Great Depression. Another wave of emigrations followed the annexation of Austria in 1938. Individual cases as well as general patterns of migration and adaptation to new environments will be examined in this presentation. One important result of the forced migrations was that many of the physicists expelled under Hitler played important roles in strengthening physics elsewhere, often on the Allied side in World War II.

  10. Neuronal Migration Disorders

    Science.gov (United States)

    ... Understanding Sleep The Life and Death of a Neuron Genes At Work In The Brain Order Publications ... birth defects caused by the abnormal migration of neurons in the developing brain and nervous system. In ...

  11. Migration og etnicitet

    DEFF Research Database (Denmark)

    Christiansen, Connie Carøe

    2004-01-01

    Migration og etnicitet er aktuelle og forbundne fænomener, idet migration øger berøringsfladerne mellem befolkningsgrupper. Etniciteter formes i takt med at grænser drages imellem disse grupper. Imod moderniserings-teoriernes forventning forsvandt etnicitet ikke som en traditionel eller oprindelig...... måde at skabe tilhørsforhold på; globalt set fremstår vor tid istedet som en "migrationens tidsalder", der tilsyneladende også er en tidsalder, hvor kulturelle særtræk, i form af etnicitet, udgør vigtige linjer, hvorefter grupper skilller sig ud fra hinanden. Både migration og etnicitet bringer fokus...... den finder sted i modtagerlandet, men nyere perspektiver på migration, som begreber om medborgerskab, transnationalisme og diaspora er eksponenter for, søger udover den nationalstatslige ramme og inddrager konsekvenserne af migrationen for afsenderlande....

  12. Law & psychiatry: punishing juveniles who kill.

    Science.gov (United States)

    Appelbaum, Paul S

    2012-10-01

    Punishment of juvenile murderers forces policy makers to weigh the developmental immaturity of adolescents against the heinousness of their crimes. The U.S. Supreme Court has progressively limited the severity of punishments that can be imposed on juveniles, holding that their impulsivity, susceptibility to peer pressure, and more fluid character render them less culpable for their actions. Having eliminated the death penalty as a punishment, the Court recently struck down mandatory life sentences without prospect of parole. The decision is interesting for its emphasis on rehabilitation, opening the door to further restrictions on punitive sentences for juveniles-and perhaps for adults too.

  13. Geochemistry and radionuclide migration

    International Nuclear Information System (INIS)

    Isherwood, D.

    1978-01-01

    Theoretically, the geochemical barrier can provide a major line of defense in protecting the biosphere from the hazards of nuclear waste. The most likely processes involved are easily identified. Preliminary investigations using computer modeling techniques suggest that retardation is an effective control on radionuclide concentrations. Ion exchange reactions slow radionuclide migration and allow more time for radioactive decay and dispersion. For some radionuclides, solubility alone may limit concentrations to less than the maximum permissible now considered acceptable by the Federal Government. The effectiveness of the geochemical barrier is ultimately related to the repository site characteristics. Theory alone tells us that geochemical controls will be most efficient in an environment that provides for maximum ion exchange and the precipitation of insoluble compounds. In site selection, consideration should be given to rock barriers with high ion exchange capacity that might also act as semi-permeable membranes. Also important in evaluating the site's potential for effective geochemical controls are the oxidation potentials, pH and salinity of the groundwater

  14. Indonesia's migration transition.

    Science.gov (United States)

    Hugo, G

    1995-01-01

    This article describes population movements in Indonesia in the context of rapid and marked social and economic change. Foreign investment in Indonesia is increasing, and global mass media is available to many households. Agriculture is being commercialized, and structural shifts are occurring in the economy. Educational levels are increasing, and women's role and status are shifting. Population migration has increased over the decades, both short and long distance, permanent and temporary, legal and illegal, and migration to and between urban areas. This article focuses specifically on rural-to-urban migration and international migration. Population settlements are dense in the agriculturally rich inner areas of Java, Bali, and Madura. Although the rate of growth of the gross domestic product was 6.8% annually during 1969-94, the World Bank ranked Indonesia as a low-income economy in 1992 because of the large population size. Income per capita is US $670. Indonesia is becoming a large exporter of labor to the Middle East, particularly women. The predominance of women as overseas contract workers is changing women's role and status in the family and is controversial due to the cases of mistreatment. Malaysia's high economic growth rate of over 8% per year means an additional 1.3 million foreign workers and technicians are needed. During the 1980s urban growth increased at a very rapid rate. Urban growth tended to occur along corridors and major transportation routes around urban areas. It is posited that most of the urban growth is due to rural-to-urban migration. Data limitations prevent an exact determination of the extent of rural-to-urban migration. More women are estimated to be involved in movements to cities during the 1980s compared to the 1970s. Recruiters and middlemen have played an important role in rural-to-urban migration and international migration.

  15. Repeat migration and disappointment.

    Science.gov (United States)

    Grant, E K; Vanderkamp, J

    1986-01-01

    This article investigates the determinants of repeat migration among the 44 regions of Canada, using information from a large micro-database which spans the period 1968 to 1971. The explanation of repeat migration probabilities is a difficult task, and this attempt is only partly successful. May of the explanatory variables are not significant, and the overall explanatory power of the equations is not high. In the area of personal characteristics, the variables related to age, sex, and marital status are generally significant and with expected signs. The distance variable has a strongly positive effect on onward move probabilities. Variables related to prior migration experience have an important impact that differs between return and onward probabilities. In particular, the occurrence of prior moves has a striking effect on the probability of onward migration. The variable representing disappointment, or relative success of the initial move, plays a significant role in explaining repeat migration probabilities. The disappointment variable represents the ratio of actural versus expected wage income in the year after the initial move, and its effect on both repeat migration probabilities is always negative and almost always highly significant. The repeat probabilities diminish after a year's stay in the destination region, but disappointment in the most recent year still has a bearing on the delayed repeat probabilities. While the quantitative impact of the disappointment variable is not large, it is difficult to draw comparisons since similar estimates are not available elsewhere.

  16. Epidemic juvenile hypothyroidism among a population of Hanford 'downwinders'

    International Nuclear Information System (INIS)

    Grossman, C.M.; Nussbaum, R.H.; Nussbaum, F.D.; Kordysh, E.; Goldsmith, J.R.

    2001-01-01

    Self-defined 'downwinders' responded to questionnaires as to their health and their potential exposures to emissions from the Hanford Nuclear Facility in the U.S. The area considered was between the Cascades and the Rocky Mountains, primarily to the East and Northeast of the facility. Of 801 questionnaires, returned, 518 were from women. Of these, 210 reported that they had been diagnosed by their physicians as having hypothyroidism. 31 of the 283 men had reported being diagnosed as hypothyroid. The condition is generally found to be frequent among adult women, but is uncommon in children. 54 of the 210 cases among females were diagnosed among those less than 20 years of age, and 5 out of 31 males were found in this age range. Peak years for diagnosis among females were from 1945 to 1965, with only three juvenile cases occurring after 1970 among 80 female hypothyroid cases overall. Among males there were five juvenile cases in 1955-1960 out of 7 overall, but no juvenile cases among 24 cases at other times. The timing of the onset of this epidemic follows closely after the massive release of I 131 from the facility in 1945, so that a causal relationship is strongly suggested. The counties of residence of cases corresponds to the counties with high cumulative dose estimates in children's thyroid glands. Validation of the diagnostic criteria was checked in a sample of cases. Other types of thyroid abnormalities were also increased. One case of juvenile thyroid cancer was reported. While thyroid cancer in adults was unusually frequent, the first cases occurred in 1955 and the highest number (8) in 1985. Our findings are consistent with the clinical finding that hypothyroidism in children frequently follows radiation of the head and neck. Similarities with the Marshall Islanders exposed to the nuclear test, 'Bravo' and to those exposed near Chernobyl are discussed. (orig.)

  17. "Investigations of salmon and steelhead trout downstream migrations in Caspar Creek and Little River, Mendocino County, March-July, 1993"

    Science.gov (United States)

    Albert Rodriguez; Weldon Jones

    1993-01-01

    Abstract - This annual study has been conducted, since 1987, on two coastal streams, in order to observe the different trend patterns of juvenile out migrations for coho salmon and steelhead-trout, figure 1. Analysis of the 1993 trapping season indicates, at Little River, a decrease of steelhead-trout yearlings but an increase in coho ""y+"". Coho...

  18. Differential toxic effects of Carbofuran and Diazinon on time of flight in pigeons (Columba livia): Potential for pesticide effects on migration

    International Nuclear Information System (INIS)

    Brasel, Jeffrey M.; Collier, Abby C.; Pritsos, Chris A.

    2007-01-01

    Cholinesterase inhibiting compounds such as carbamates and organophosphate insecticides have been widely used in agriculture since the ban on organochlorines in the 1970s. Carbofuran, a carbamate, and diazinon, an organophosphate, are among the most commonly implicated cholinesterase inhibitors in episodes of accidental avian toxicity and mortality. Despite the apparent effects of these compounds, little work has been done to study effects of low-level, environmentally relevant doses at the population level in migratory bird species. In this study, homing pigeons were used as surrogate species to assess the differences in the effect of incrementally low doses (0.0, 0.25, 0.5, and 1.0 mg/kg) of carbofuran and diazinon on time of flight and determine whether there was a threshold dose of either or both xenobiotics when orally administered at these levels. The results indicate that there is a significant dose-dependent increase in flight time in pigeons dosed with carbofuran while diazinon exposed pigeons showed little effect. More profound effects were noted with carbofuran with pigeons falling off the pace of the flock and a dose for highly significant increase in flight time elucidated between 0.5 and 1.0 mg/kg. The results of the studies validate the homing pigeon as a good subject for comparative studies of cholinesterase inhibitors in birds and the need for further research on repeated low-level exposures on populations of avian species

  19. Conceptualizing juvenile prostitution as child maltreatment: findings from the National Juvenile Prostitution Study.

    Science.gov (United States)

    Mitchell, Kimberly J; Finkelhor, David; Wolak, Janis

    2010-02-01

    Two studies were conducted to identify the incidence (Study 1) and characteristics (Study 2) of juvenile prostitution cases known to law enforcement agencies in the United States. Study 1 revealed a national estimate of 1,450 arrests or detentions (95% confidence interval [CI]: 1,287-1,614) in cases involving juvenile prostitution during a 1-year period. In Study 2, exploratory data were collected from a subsample of 138 cases from police records in 2005. The cases are broadly categorized into three main types: (a) third-party exploiters, (b) solo prostitution, and (c) conventional child sexual abuse (CSA) with payment. Cases were classified into three initial categories based on police orientation toward the juvenile: (a) juveniles as victims (53%), (b) juveniles as delinquents (31%), and (c) juvenile as both victims and delinquents (16%). When examining the status of the juveniles by case type, the authors found that all the juveniles in CSA with payment cases were treated as victims, 66% in third-party exploiters cases, and 11% in solo cases. Findings indicate law enforcement responses to juvenile prostitution are influential in determining whether such youth are viewed as victims of commercial sexual exploitation or as delinquents.

  20. Modification of meander migration by bank failures

    Science.gov (United States)

    Motta, D.; Langendoen, E. J.; Abad, J. D.; García, M. H.

    2014-05-01

    Meander migration and planform evolution depend on the resistance to erosion of the floodplain materials. To date, research to quantify meandering river adjustment has largely focused on resistance to erosion properties that vary horizontally. This paper evaluates the combined effect of horizontal and vertical floodplain material heterogeneity on meander migration by simulating fluvial erosion and cantilever and planar bank mass failure processes responsible for bank retreat. The impact of stream bank failures on meander migration is conceptualized in our RVR Meander model through a bank armoring factor associated with the dynamics of slump blocks produced by cantilever and planar failures. Simulation periods smaller than the time to cutoff are considered, such that all planform complexity is caused by bank erosion processes and floodplain heterogeneity and not by cutoff dynamics. Cantilever failure continuously affects meander migration, because it is primarily controlled by the fluvial erosion at the bank toe. Hence, it impacts migration rates and meander shapes through the horizontal and vertical distribution of erodibility of floodplain materials. Planar failures are more episodic. However, in floodplain areas characterized by less cohesive materials, they can affect meander evolution in a sustained way and produce preferential migration patterns. Model results show that besides the hydrodynamics, bed morphology and horizontal floodplain heterogeneity, floodplain stratigraphy can significantly affect meander evolution, both in terms of migration rates and planform shapes. Specifically, downstream meander migration can either increase or decrease with respect to the case of a homogeneous floodplain; lateral migration generally decreases as result of bank protection due to slump blocks; and the effect on bend skewness depends on the location and volumes of failed bank material caused by cantilever and planar failures along the bends, with possible achievement of