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1

Phyllostomid Bat Occurrence in Successional Stages of Neotropical Dry Forests  

PubMed Central

Tropical dry forests (TDFs) are highly endangered tropical ecosystems being replaced by a complex mosaic of patches of different successional stages, agricultural fields and pasturelands. In this context, it is urgent to understand how taxa playing critical ecosystem roles respond to habitat modification. Because Phyllostomid bats provide important ecosystem services (e.g. facilitate gene flow among plant populations and promote forest regeneration), in this study we aimed to identify potential patterns on their response to TDF transformation in sites representing four different successional stages (initial, early, intermediate and late) in three Neotropical regions: México, Venezuela and Brazil. We evaluated bat occurrence at the species, ensemble (abundance) and assemblage level (species richness and composition, guild composition). We also evaluated how bat occurrence was modulated by the marked seasonality of TDFs. In general, we found high seasonal and regional specificities in phyllostomid occurrence, driven by specificities at species and guild levels. For example, highest frugivore abundance occurred in the early stage of the moistest TDF, while highest nectarivore abundance occurred in the same stage of the driest TDF. The high regional specificity of phyllostomid responses could arise from: (1) the distinctive environmental conditions of each region, (2) the specific behavior and ecological requirements of the regional bat species, (3) the composition, structure and phenological patterns of plant assemblages in the different stages, and (4) the regional landscape composition and configuration. We conclude that, in tropical seasonal environments, it is imperative to perform long-term studies considering seasonal variations in environmental conditions and plant phenology, as well as the role of landscape attributes. This approach will allow us to identify potential patterns in bat responses to habitat modification, which constitute an invaluable tool for not only bat biodiversity conservation but also for the conservation of the key ecological processes they provide. PMID:24404175

Avila-Cabadilla, Luis Daniel; Stoner, Kathryn Elizabeth; Nassar, Jafet M.; Espírito-Santo, Mario M.; Alvarez-Añorve, Mariana Yolotl; Aranguren, Carla I.; Henry, Mickael; González-Carcacía, José A.; Dolabela Falcão, Luiz A.; Sanchez-Azofeifa, Gerardo Arturo

2014-01-01

2

Phyllostomid bat occurrence in successional stages of neotropical dry forests.  

PubMed

Tropical dry forests (TDFs) are highly endangered tropical ecosystems being replaced by a complex mosaic of patches of different successional stages, agricultural fields and pasturelands. In this context, it is urgent to understand how taxa playing critical ecosystem roles respond to habitat modification. Because Phyllostomid bats provide important ecosystem services (e.g. facilitate gene flow among plant populations and promote forest regeneration), in this study we aimed to identify potential patterns on their response to TDF transformation in sites representing four different successional stages (initial, early, intermediate and late) in three Neotropical regions: México, Venezuela and Brazil. We evaluated bat occurrence at the species, ensemble (abundance) and assemblage level (species richness and composition, guild composition). We also evaluated how bat occurrence was modulated by the marked seasonality of TDFs. In general, we found high seasonal and regional specificities in phyllostomid occurrence, driven by specificities at species and guild levels. For example, highest frugivore abundance occurred in the early stage of the moistest TDF, while highest nectarivore abundance occurred in the same stage of the driest TDF. The high regional specificity of phyllostomid responses could arise from: (1) the distinctive environmental conditions of each region, (2) the specific behavior and ecological requirements of the regional bat species, (3) the composition, structure and phenological patterns of plant assemblages in the different stages, and (4) the regional landscape composition and configuration. We conclude that, in tropical seasonal environments, it is imperative to perform long-term studies considering seasonal variations in environmental conditions and plant phenology, as well as the role of landscape attributes. This approach will allow us to identify potential patterns in bat responses to habitat modification, which constitute an invaluable tool for not only bat biodiversity conservation but also for the conservation of the key ecological processes they provide. PMID:24404175

Avila-Cabadilla, Luis Daniel; Stoner, Kathryn Elizabeth; Nassar, Jafet M; Espírito-Santo, Mario M; Alvarez-Añorve, Mariana Yolotl; Aranguren, Carla I; Henry, Mickael; González-Carcacía, José A; Dolabela Falcão, Luiz A; Sanchez-Azofeifa, Gerardo Arturo

2014-01-01

3

Changes in Forest Soil Properties in Different Successional Stages in Lower Tropical China  

PubMed Central

Background Natural forest succession often affects soil physical and chemical properties. Selected physical and chemical soil properties were studied in an old-growth forest across a forest successional series in Dinghushan Nature Reserve, Southern China. Methodology/Principal Findings The aim was to assess the effects of forest succession change on soil properties. Soil samples (0–20 cm depth) were collected from three forest types at different succession stages, namely pine (Pinus massoniana) forest (PMF), mixed pine and broadleaf forest (PBMF) and monsoon evergreen broadleaf forest (MEBF), representing early, middle and advanced successional stages respectively. The soil samples were analyzed for soil water storage (SWS), soil organic matter (SOM), soil microbial biomass carbon (SMBC), pH, NH4+-N, available potassium (K), available phosphorus (P) and microelements (available copper (Cu), available zinc (Zn), available iron (Fe) and available boron (B)) between 1999 and 2009. The results showed that SWS, SOM, SMBC, Cu, Zn, Fe and B concentrations were higher in the advanced successional stage (MEBF stage). Conversely, P and pH were lower in the MEBF but higher in the PMF (early successional stage). pH, NH4+-N, P and K declined while SOM, Zn, Cu, Fe and B increased with increasing forest age. Soil pH was lower than 4.5 in the three forest types, indicating that the surface soil was acidic, a stable trend in Dinghushan. Conclusion/Significance These findings demonstrated significant impacts of natural succession in an old-growth forest on the surface soil nutrient properties and organic matter. Changes in soil properties along the forest succession gradient may be a useful index for evaluating the successional stages of the subtropical forests. We caution that our inferences are drawn from a pseudo-replicated chronosequence, as true replicates were difficult to find. Further studies are needed to draw rigorous conclusions regarding on nutrient dynamics in different successional stages of forest. PMID:24244738

Li, Yuelin; Yang, Fangfang; Ou, Yangxu; Zhang, Deqiang; Liu, Juxiu; Chu, Guowei; Zhang, Yaru; Otieno, Dennis; Zhou, Guoyi

2013-01-01

4

The seed bank in an estonian calcareous grassland: Comparison of different successional stages  

Microsoft Academic Search

Seed bank species-composition and seed-density were determined in a successional calcareous (alvar) grassland in western Estonia.\\u000a Three similar study areas were chosen to compare two different successional stages: open alvar grassland and overgrown areas\\u000a with young pine forest 30 to 40 years old. In both successional stages, the centre and the edge of a relatively uniform stand\\u000a were examined. Fifteen

Rein Kalamees; Martin Zobel

1997-01-01

5

The effect of forest successional stage on seed removal of tropical rain forest tree species  

Microsoft Academic Search

Seed removal was evaluated at the macro- and micro-habitat level in areas differing in successional stage in the Bolivian Amazon. The successional stages consisted of secondary forests of 2, 10 and 20 years old and primary forest. Seeds of nine tree species were artificially dispersed and the number of seeds removed was evaluated over 7 weeks. Several stand characteristics were

Marielos Peña-Claros; Henneleen De Boo

2002-01-01

6

Phenotypic Plasticity of Early and Late Successional Forbs in Response to Shifts in Resources  

PubMed Central

We compared the phenotypic plasticity of two early successional forbs of nutrient-poor mobile dunes (Agriophyllum squarrosum and Corispermum macrocarpum) and two later successional forbs (weeds) of stabilized, higher nutrient dunes and cropland (Chenopodium acuminatum and Salsola collina) to variations in environmental factors. A controlled (including soil nutrients, water, and population density) greenhouse experiment was conducted in Horqin sandy land, China. Late successional species had high plasticity in growth response to nutrients and water or high performance in high soil nutrients and water, reflecting their higher nutrient habitat. In contrast, the early successional species have low plasticity, reflecting their adaptation to resource-poor early successional soil. Late successional species did not always have higher reproductive effort than early successional species. Plants did not have a uniform strategy of increasing reproductive effort with any environmental stressors. Reproductive effort increased with increasing water availability and decreasing nutrient levels, while density had no effect. Patterns of plasticity traits for late successional species exhibited a complex of Master-of-some and Jack-of-all-trades. Late successional species had higher performance or higher plasticity than early successional species. PMID:23185600

Huang, Yingxin; Zhao, Xueyong; Zhou, Daowei; Zhang, Hongxiang; Zheng, Wei

2012-01-01

7

Influence of biological soil crusts at different successional stages in the implantation of biogeochemical cycles in arid and semiarid zones  

NASA Astrophysics Data System (ADS)

Influence of biological soil crusts at different successional stages in the implantation of biogeochemical cycles in arid and semiarid zones I. Miralles1, F. Gil-Sotres2, Y. Cantón-Castilla3, F. Domingo1, M.C. Leirós2, C. Trasar-Cepeda4 1 Experimental Estation of Arid Zones (CSIC), E-04230 La Cañada de San Urbano, Almería, Spain. 2 Departamento Edafología y Química Agrícola, Grupo de Evaluación de la Calidad del Suelo, Unidad Asociada CSIC, Facultad de Farmacia, Universidad de Santiago de Compostela, E-15782 Santiago de Compostela, Spain. 3 University of Almería, Departamento de Edafología y Química Agrícola, E-04230-La Cañada de San Urbano, Almería, Spain. 4 Departamento Bioquímica del Suelo, IIAG-CSIC, Apartado 122, E-15708 Santiago de Compostela, Spain. Crusts (BSCs) are formed by a close association between soil particles and cyanobacteria, algae, lichens, bryophytes and microfungi in varying proportions. Their habitat is within or immediately on top of the uppermost millimetres of the soil and are the predominant surface cover in arid and semiarid zones. Among the diverse functions developed by BSCs in the ecosystem (hydrology, erosion, soil properties, etc.), one of the most important is its role in nutrient cycling. Within arid and semiarid environments, BSCs have been termed 'mantles of fertility' being considered hotspots of biogeochemical inputs, fixing C, N and P above- and below-ground. However, there are differences in N and C fixation rates between BSCs types. Early successional BSCs, dominated by cyanobacterial species, fix lower quantities of C and N than mature BSCs dominated by lichens. Although the positive effects of BSCs on biogeochemical soil cycles are widely accepted, no previous studies have evaluated the activities of the enzymes involved in C, N and P cycles of BSCs and how they are affected by the successional stage of the BSC. In this work, performed in the Tabernas desert (SE Spain), we studied the hydrolase enzymes involved in C (invertase, CM-cellulase, ?-glucosidase), N (urease, BAA-protease, casein-protease) and P (phosphomonoesterase) cycles in BSCs at different successional stages (cyanobacteria represents the first successional stage, lichen Diploschistes diacapsis in an intermediate state and lichen Lepraria crassissima, with the greatest successional state). Our results show that BSCs at lower successional stage enriched the surface geological substrate in hydrolase enzymes to a lesser extent than mature BSCs (Lepraria crassissima), which show the highest values in all enzymatic activities. In contrast, the specific enzyme activities (activity values expressed per unit of carbon) were higher in the BSCs at lower successional stage, decreasing in the direction: cyanobacteria > Diploschistes diacapsis-lichen > Lepraria crassissima-lichen. These results suggest a different role of BSCs depending on their successional stage with regard to the implantation of biogeochemical cycles during the surface substrate colonization. Our conclusions are highly relevant to improve the knowledge of biogeochemical cycles in arid and semiarid areas. Keywords: Biological Soil Crusts, arid ecosystems, hydrolytic enzymes, biochemical activity

Gil-Sotres, F.; Miralles, I.; Canton-Castilla, Y.; Domingo, F.; Leiros, M. C.; Trasar-Cepeda, C.

2012-04-01

8

Abundance, distribution, trends, and ownership patterns of early-successional forests in the northeastern United States  

Microsoft Academic Search

Early-successional forests are ephemeral and distinct forest communities, maintained by disturbance and dominated by small-sized trees and shrubs. These structural and compositional conditions form a unique habitat that is preferred by many wildlife species. Various sources have indicated that there have been declines in early-successional forest area and in the populations of many wildlife species associated with these habitats across

Robert T. Brooks

2003-01-01

9

Predicting forest successional stages using multitemporal Landsat imagery with forest inventory and analysis data  

Microsoft Academic Search

Forest succession is an important ecological process that has profound biophysical, biological and biogeochemical implications in terrestrial ecosystems. Therefore, information on forest successional stages over an extensive forested landscape is crucial for us to understand ecosystem processes, such as carbon assimilation and energy interception. This study explored the potential of using Forest Inventory and Analysis (FIA) plot data to extract

W. Liu; C. Song; T. A. Schroeder; W. B. Cohen

2008-01-01

10

Predicting temperate conifer forest successional stage distributions with multitemporal Landsat Thematic Mapper imagery  

Microsoft Academic Search

Forest succession is a fundamental ecological process which can impact the functioning of many terrestrial processes, such as water and nutrient cycling and carbon sequestration. Therefore, knowing the distribution of forest successional stages over a landscape facilitates a greater understanding of terrestrial ecosystems. One way of characterizing forest succession over the landscape is to use satellite imagery to map forest

Conghe Song; Todd A. Schroeder; Warren B. Cohen

2007-01-01

11

Spatial analysis of early successional, temperate forest community structure  

NASA Astrophysics Data System (ADS)

The global importance of sequestration of carbon by temperate forests makes characterizing the regrowth of these forests post-disturbance both ecologically and economically important. High intensity disturbances, such as logging, result in substantial alteration of community composition post-disturbance, creating the potential for alterations to the cycling of carbon, water, and nutrients in the ecosystem. Because logging pressure in New England continues to increase, understanding how forest ecosystems in this region respond to disturbance is crucial. This study aims to characterize interspecies interactions within New England forests by identifying synchronous and asynchronous colocation of species following a disturbance. To accomplish this, line-intercept surveys of vegetation were conducted in a clearcut forest stand located within the Harvard Forest LTER site. Survey data collected two (2010) and five (2013) years post-clearcut were analyzed using a one-dimensional Ripley's K. From 2010 to 2013, an increase in the number of interspecies relationships was observed, indicating the development of community structure. Additionally, the analysis found an increase in total vegetative cover from 2010 to 2013, and also found the majority of observed interspecies relationships to be asynchronous relationships. Together, these results imply an increase in resource competition that had the potential to drive the increase in community structure. Specifically, an increase in community structure led to the development of three distinct sub-communities: homogenous fern, tree seedling canopy over ground cover, and shrub dominated. This creates a patchy landscape in the early successional forest that allows for high species diversity (Shannon's H = 2.455). Based on the results of the Ripley's K analyses, species demonstrated definite patterns of synchronicity and asynchronicity based on both specific species interactions as well as functional group interactions. These analyses have important application for species conservation and for predicting the regeneration of tree seedlings, and provide unique information about the interspecies interactions of New England forest communities during one of the most rich and dynamic phases of succession, allowing for more informed decisions to be made regarding the regrowth of forests following a high-intensity disturbance.

Walker, R. H.; Williams, C. A.; MacLean, R. G.; Epstein, H. E.; Vanderhoof, M. K.

2013-12-01

12

Importance of early successional habitat to ruffed grouse and American woodcock  

USGS Publications Warehouse

Ruffed grouse (Bonasa umbellus) and American woodcock (Scolopax minor) provide millions of days of recreation each year for people in the eastern United States (U.S). These popular game birds depend on early successional forest habitats throughout much of the year. Ruffed grouse and woodcock populations are declining in the eastern United States as an abundance of shrub-dominated and young forest habitats decrease in most of the region. Continued decreases in early successional forest habitats are likely on nonindustrial private forest lands as ownership fragmentation increases and tract size decreases and on public forest lands due to societal attitudes toward proactive forest management, especially even-age treatments.

Dessecker, D.R.; McAuley, D.G.

2001-01-01

13

Forest Successional Stage Affects the Cortical Secondary Chemistry of Three Old Forest Lichens  

Microsoft Academic Search

Three epiphytic old forest lichens (Usnea longissima, Pseudocyphellaria crocata, and Lobaria pulmonaria) were transplanted along a natural shade–sun gradient comprising three successional stages in boreal spruce forests (dense\\u000a young forest, open old forest, and clear-cut) for one summer. After harvest, extractable secondary compounds were analyzed\\u000a by high-performance liquid chromatography, and the brown pigmentation in melanic species was quantified by reflectance

Line Nybakken; Johan Asplund; Knut Asbjørn Solhaug; Yngvar Gauslaa

2007-01-01

14

Spectral identification of successional stages following deforestation in the Amazon  

Microsoft Academic Search

Land use and land cover features of a 3,000 sq. km. area west of Altamira, State of Para, Brazil, along the Transamazon Highway was assessed using three dates of Landsat TM data acquired for late July\\/early August 1985, 2988, and 1991. These data, supplemented by field observations and interviews with land users conducted in 1992, permitted classification of nine features,

Paul Mausel; You Wu; Yinghong Li; Emilio F. Moran; Eduardo S. Brondizio

1993-01-01

15

Arbuscular Mycorrhizal Fungal Networks Vary throughout the Growing Season and between Successional Stages  

PubMed Central

To date, few analyses of mutualistic networks have investigated successional or seasonal dynamics. Combining interaction data from multiple time points likely creates an inaccurate picture of the structure of networks (because these networks are aggregated across time), which may negatively influence their application in ecosystem assessments and conservation. Using a replicated bipartite mutualistic network of arbuscular mycorrhizal (AM) fungal-plant associations, detected using large sample numbers of plants and AM fungi identified through molecular techniques, we test whether the properties of the network are temporally dynamic either between different successional stages or within the growing season. These questions have never been directly tested in the AM fungal-plant mutualism or the vast majority of other mutualisms. We demonstrate the following results: First, our examination of two different successional stages (young and old forest) demonstrated that succession increases the proportion of specialists within the community and decreases the number of interactions. Second, AM fungal-plant mutualism structure changed throughout the growing season as the number of links between partners increased. Third, we observed shifts in associations between AM fungal and plant species throughout the growing season, potentially reflecting changes in biotic and abiotic conditions. Thus, this analysis opens up two entirely new areas of research: 1) identifying what influences changes in plant-AM fungal associations in these networks, and 2) what aspects of temporal variation and succession are of general importance in structuring bipartite networks and plant-AM fungal communities. PMID:24358265

Bennett, Alison Elizabeth; Daniell, Tim John; Öpik, Maarja; Davison, John; Moora, Mari; Zobel, Martin; Selosse, Marc-André; Evans, Darren

2013-01-01

16

Altered soil organic carbon stability in eastern deciduous forest: interplay between forest successional Stage and invasive earthworm activity  

NASA Astrophysics Data System (ADS)

Detritivore -mediated decomposition and incorporation of aboveground litter is an important processes in soil carbon cycle of forest ecosystems that can be a major control on the proportion of stable and unstable soil carbon pools. We investigated how earthworm activity interacts with litter type to alter the stability of soil organic carbon (SOC) in an eastern deciduous successional forest within at the Smithsonian Environmental Research Center (SERC). Soil C and N content and chemistry (lignin and fatty acids) among particulate and mineral-bound fractions was shifted after 5 years of litter (wood and leaf) addition but with significant differences among the forest successional stages and with earthworm activity. Results from a 6 month laboratory incubation (25°C and 15°C) of bulk soil samples taken from the treatments and incubated at 25°C and 15°C demonstrate that litter addition type and earthworm activity interacted to control the proportion of labile and stable carbon. Specifically, the labile C pools in double wood and control treatments were highest in young successional forest with higher earthworm activity. However, in the double leaf treatment, the labile C pool was higher in old successional forests with less worm activity. In general, the stable C pool, released after one month, was higher in old successional forests for all three treatments. The difference of the stable pool between young and old successional forest was the largest with double wood treatment, followed by control treatment and the lowest with double leaf treatment. In summary, wood treatment shifted SOC pool to relatively more stable pool in old successional forests decreasing labile C pool but not the young sites. While double leaf treatment increased the labile pool in old forests but in young successional forests, SOC shifted to relatively more stable pool by decreasing the labile pool and increasing the stable pool. This result indicates that the type of aboveground litter input interact with earthworm activity will largely influence SOC stability and soil C cycling in deciduous forests at different successional stages.

Ma, Y.; Filley, T. R.; McCormick, M.; Szlavecz, K. A.

2012-12-01

17

Colonization of experimentally created gaps along an alpine successional gradient  

Microsoft Academic Search

The colonization of artificially created gaps was analyzed along an alpine successional gradient from pioneer to early, late,\\u000a and old successional stages. The presence\\/absence of species and the abundances of seedlings and adults in the gaps were recorded\\u000a and compared with those of the surrounding areas. We hypothesized that in the older successional stages, the gaps were likely\\u000a to be

Kay Cichini; Erich Schwienbacher; Silvia Marcante; Gilg U. H. Seeber; Brigitta Erschbamer

18

Landscape genetics of an early successional specialist in a disturbance-prone environment.  

PubMed

Species that specialize in disturbed habitats may have considerably different dispersal strategies than those adapted to more stable environments. However, little is known of the dispersal patterns and population structure of such species. This information is important for conservation because many postfire specialists are at risk from anthropogenic changes to natural disturbance regimes. We used microsatellite markers to assess the effect of landscape variation and recent disturbance history on dispersal by a small mammal species that occupies the early seral stage of vegetation regeneration in burnt environments. We predicted that a postfire specialist would be able to disperse over multiple habitat types (generalist) and not exhibit sex-biased dispersal, as such strategies should enable effective colonization of spatially and temporally variable habitat. We found significant differentiation between sites that fitted an isolation-by-distance pattern and spatial autocorrelation of multilocus genotypes to a distance of 2-3 km. There was no consistent genetic evidence for sex-biased dispersal. We tested the influence of different habitat- and fire-specific landscape resistance scenarios on genetic distance between individuals and found a significant effect of fire. Our genetic data supported recently burned vegetation having greater conductance for gene flow than unburnt habitat, but variation in habitat quality between vegetation types and occupied patches had no effect on gene flow. Postfire specialists must evolve an effective dispersal ability to move over distances that would ensure access to early successional stage vegetation. Natural disturbance and natural heterogeneity may therefore not influence population genetic structure as negatively as expected. PMID:23379886

Pereoglou, F; Lindenmayer, D B; MacGregor, C; Ford, F; Wood, J; Banks, S C

2013-03-01

19

Successional stage, fragmentation and exposure to extraction influence the population structure of Euterpe precatoria (Arecaeae).  

PubMed

The neotropical palm Euterpeprecatoria is subject to extraction for its valuable palm heart. The development of management and conservation practices for this species requires understanding of its population structure, dynamics, and traditional use across the range of environments it inhabits, from different successional stages in continuous forest to forest fragments. Here, we analyzed how the population structure of E. precatoria varies with successional stage, fragmentation, and exposure to extraction, Since E. precatoria recruitment increases with disturbance, we expected seedling density to be higher in secondary forests and fragments relative to primary forests. The study was conducted from 2007-2008 in the Caribbean Slope of Costa Rica at Braulio Carrillo National Park (BCNP), La Selva Biological Station (LSBS), Manú Center, and Finca El Progreso (FEP). The first two sites had continuous primary and secondary forests (BCNP had one extracted primary forest); the last two consisted of primary forest fragments. Population structure was variable, with greater densities in the extracted primary forest, and in the secondary forests, as compared to primary forests and fragments. Palms < 5 m across all sites represented 50-90% of the total number of individuals. In sites that suffered historical over-extraction, local communities have lost the tradition of consuming this species. Understanding how population dynamics is affected by extraction and succession is essential to the design of sustainable management programs rooted in community participation. PMID:24027932

Avalos, Gerardo; Otárola, Mauricio Fernández; Engeln, James Theodore

2013-09-01

20

Bats and Gaps: The Role of Early Successional Patches in the Roosting and Foraging Ecology of Bats  

Microsoft Academic Search

\\u000a Early successional habitats are important foraging and commuting sites for the 14 species of bats that inhabit the Central\\u000a Hardwood Region, especially larger open-adapted species such as hoary bats (Lasiurus cinereus), red bats (L. borealis), silver-haired bats (Lasionycteris noctivagans), and big brown bats (Eptesicus fuscus). Forest gaps, small openings, and the edges between early successional patches and mature forest are

Susan C. Loeb; Joy M. O’Keefe

21

Invasive Earthworms and Forest Successional Stage Interact to Impact Plant Litter Inputs and Particulate Organic Matter Chemistry  

Technology Transfer Automated Retrieval System (TEKTRAN)

The landscapes colonized by invasive earthworms in the eastern U.S. are often patchworks of forest stands in various stages of successional development. We established six field sites in tulip poplar dominated forests in the Smithsonian Environmental Research Center Forest (SERC), MD, that span you...

22

Genetic, morphological and spatial characterization of two populations of Mabea fistulifera Mart. (Euphorbiaceae), in different successional stages  

Microsoft Academic Search

Two popu lations of Mabea fistulifera (Euphorbiaceae) located a t Rio Doce State Park (Minas Gerais, Brazil) in places characterized as in d ifferent successional stages, were investigated through genetic and ecological traits. Twenty randomly chosen individuals from each population had its genetic data assessed by 43 RAPD markers and were also evaluated through five morphologic traits and its spatial

Maíra Figueiredo Goulart; Sérvio Pontes Ribeiro; Maria Bernadete Lovato

2005-01-01

23

Sensitivity of understorey bird species in two different successional stages of the lowland Atlantic Forest, Brazil.  

PubMed

The Atlantic Forest has a high destruction rate and there is little information available on some aspects of the neotropical bird biology. Changes in environment are important factors that affect the resources available to birds. We compared the species sensitivity level of understorey birds in two areas in distinct successional stages (primary and secondary sections). Two 100 ha plots of lowland Atlantic Forest were analysed between August and December 2006. Among 25 bird species recorded, thirteen had lower abundance in secondary forest, two in primary forest, and ten had not clear tendency. According to the criteria used, the percentages for species with low, and medium and high sensitivity to habitat change were 44% and 56%, respectively. The number of species was not associated with the endemism level or foraging strata. Results show the importance of knowing bird species' sensitivity level with regard to habitat modification, and not only forest fragmentation. PMID:21969964

Loures-Ribeiro, Alan; Manhães, Marco A; Dias, Manoel M

2011-09-01

24

Demographic variation across successional stages and their effects on the population dynamics of the neotropical palm Euterpe precatoria.  

PubMed

• Premise of the study: Environmental heterogeneity is a strong selective force shaping adaptation and population dynamics across temporal and spatial scales. Natural and anthropogenic gradients influence the variation of environmental and biotic factors, which determine population demography and dynamics. Successional gradients are expected to influence demographic parameters, but the relationship between these gradients and the species life history, habitat requirements, and degree of variation in demographic traits remains elusive.• Methods: We used the palm Euterpe precatoria to test the effect of successional stage on plant demography within a continuous population. We calculated demographic parameters for size stages and performed matrix analyses to investigate the demographic variation within primary and secondary forests of La Selva, Costa Rica.• Key results: We observed differences in mortality and recruitment of small juveniles between primary and secondary forests. Matrix models described satisfactorily the chronosequence of population changes, which were characterized by high population growth rate in disturbed areas, and decreased growth rate in old successional forests until reaching stability.• Conclusions: Different demographic parameters can be expressed in contiguous subpopulations along a gradient of successional stages with important consequences for population dynamics. Demographic variation superimposed on these gradients contributes to generate subpopulations with different demographic composition, density, and ecological properties. Therefore, the effects of spatial variation must be reconsidered in the design of demographic analyses of tropical palms, which are prime examples of subtle local adaptation. These considerations are crucial in the implementation of management plans for palm species within spatially complex and heterogeneous tropical landscapes. PMID:24907255

Otárola, Mauricio Fernández; Avalos, Gerardo

2014-06-01

25

Facilitative and inhibitory effect of litter on seedling emergence and early growth of six herbaceous species in an early successional old field ecosystem.  

PubMed

In the current study, a field experiment was conducted to examine effects of litter on seedling emergence and early growth of four dominant weed species from the early successional stages of old field ecosystem and two perennial grassland species in late successional stages. Our results showed that increased litter cover decreased soil temperature and temperature variability over time and improved soil moisture status. Surface soil electrical conductivity increased as litter increased. The increased litter delayed seedling emergence time and rate. The emergence percentage of seedlings and establishment success rate firstly increased then decreased as litter cover increased. When litter biomass was below 600 g m(-2), litter increased seedlings emergence and establishment success in all species. With litter increasing, the basal diameter of seedling decreased, but seedling height increased. Increasing amounts of litter tended to increase seedling dry weight and stem leaf ratio. Different species responded differently to the increase of litter. Puccinellia tenuiflora and Chloris virgata will acquire more emergence benefits under high litter amount. It is predicted that Chloris virgata will dominate further in this natural succession old field ecosystem with litter accumulation. Artificial P. tenuiflora seeds addition may be required to accelerate old field succession toward matured grassland. PMID:25110722

Li, Qiang; Yu, Pujia; Chen, Xiaoying; Li, Guangdi; Zhou, Daowei; Zheng, Wei

2014-01-01

26

Projected Effects of CO2 Enrichment on Community Dynamics and Carbon Cycling in an Early-successional Forest  

NASA Astrophysics Data System (ADS)

Early-successional forests are strong carbon (C) sinks that play an important role in the global C cycle. Elevated CO2 may alter C cycling in regenerating forests both directly through ecophysiological mechanisms and indirectly through altered community dynamics, which may be particularly important in early successional forests with high community turnover. Thus, to discriminate impacts of CO2 enrichment on C cycles in regenerating forests it is necessary to characterize how the physiological and successional mechanisms that regulate the C cycle are altered by climate change. Because species are known to display differential growth stimulus under CO2 enrichment, and these species-specific effects are grouped by classic plant functional type, we hypothesize that successional trajectories will be altered in high CO2 forests, compared to forests regenerating under historic climatic conditions. To test this hypothesis, we use the Ecosystem Demography model (ED2), a height- and successional-structured terrestrial biosphere model to predict possible effects of elevated CO2 on forest succession. Using data from the Duke Free Air CO2 Enrichment (FACE) experiment and a nearby chronosequence of pine forests to parameterize and evaluate the model, we use ED2 to project how plant demography and competition will react to elevated CO2 over a 50-100 year time frame. We evaluate the sensitivity of model results to a variety of model configurations, and demonstrate that the outcomes are largely robust to structural uncertainty regarding assumptions about nitrogen limitation and water availability. The model predicts that elevated CO2 will alter C cycling directly through ecophysiological effect and indirectly through altered community dynamics, which in turn affect C cycling. For instance, late-successional hardwood species will receive more benefit on average from elevated CO2, than early-successional hardwoods. After 50 years of 550 ppm CO2, late-successional hardwoods experience a significant increase in maximum summer NPP, while early successional species experience decreases in summer NPP, due to increased resource competition with late-successional functional types. These results illustrate that differential responses to elevated CO2 across functional groups alter community dynamics and thereby ecosystem-level C cycling.

Miller, A. D.; Dietze, M.; DeLucia, E. H.; Anderson-Teixeira, K. J.

2013-12-01

27

Hyperspectral reflectance of leaves and flowers of an outbreak species discriminates season and successional stage of vegetation  

NASA Astrophysics Data System (ADS)

Spectral reflectance can be used to assess large-scale performances of plants in the field based on plant nutrient balance as well as composition of defence compounds. However, plant chemical composition is known to vary with season - due to its phenology - and it may even depend on the succession stage of its habitat. Here we investigate (i) how spectral reflectance could be used to discriminate successional and phenological stages of Jacobaea vulgaris in both leaf and flower organs and (ii) if chemical content estimation by reflectance is flower or leaf dependent. We used J. vulgaris, which is a natural outbreak plant species on abandoned arable fields in north-western Europe and studied this species in a chronosequence representing successional development during time since abandonment. The chemical content and reflectance between 400 and 2500 nm wavelengths of flowers and leaves were measured throughout the season in fields of different successional ages. The data were analyzed with multivariate statistics for temporal discrimination and estimation of chemical contents in both leaf and flower organs. Two main effects were revealed by spectral reflectance measurements: (i) both flower and leaf spectra show successional and seasonal changes, but the pattern is complex and organ specific (ii) flower head pyrrolizidine alkaloids, which are involved in plant defence against herbivores, can be detected through hyperspectral reflectance.We conclude that spectral reflectance of both leaves and flowers can provide information on plant performance during season and successional stages. As a result, remote sensing studies of plant performance in complex field situations will benefit from considering hyperspectral reflectance of different plant organs. This approach may enable more detailed studies on the link between spectral information and plant defence dynamics both aboveground and belowground.

Carvalho, Sabrina; Schlerf, Martin; van der Putten, Wim H.; Skidmore, Andrew K.

2013-10-01

28

Overwinter survival of neotropical migratory birds in early successional and mature tropical forests  

USGS Publications Warehouse

Many Neotropical migratory species inhabit both mature and early successional forest on their wintering grounds, yet comparisons of survival rates between habitats are lacking. Consequently, the factors affecting habitat suitability for Neotropical migrants and the potential effects of tropical deforestation on migrants are not well understood. We estimated over-winter survival and capture probabilities of Wood Thrush (Hylocichla mustelina), Ovenbird (Seiurus aurocapillus), Hooded Warbler (Wilsonia citrina), and Kentucky Warbler (Oporomis formosus) inhabiting two common tropical habitat types, mature and early-successional forest. Our results suggest that large differences (for example, ratio of survival rates (gamma) < 0.85) in overwinter survival between these habitats do not exist for any of these species. Age ratios did not differ between habitats, but males were more common in forest habitats and females more common in successional habitats for Hooded Warblers and Kentucky Warblers. Future research on overwinter survival should address the need for age- and sex-specific survival estimates before we can draw strong conclusions regarding winter habitat suitability. Our estimates of over-winter survival extrapolated to annual survival rates that were generally lower than previous estimates of annual survival of migratory birds. Capture probability differed between habitats for Kentucky Warblers, but our results provide strong evidence against large differences in capture probability between habitats for Wood Thrush, Hooded Warblers, and Ovenbirds. We found no temporal or among site differences in survival or capture probability for any of the four species. Additional research is needed to examine the effects of winter habitat use on survival during migration and between-winter survival.

Conway, C.J.; Powell, G.V.N.; Nichols, J.D.

1995-01-01

29

Early stage colon cancer  

PubMed Central

Evidence has now accumulated that colonoscopy and removal of polyps, especially during screening and surveillance programs, is effective in overall risk reduction for colon cancer. After resection of malignant pedunculated colon polyps or early stage colon cancers, long-term repeated surveillance programs can also lead to detection and removal of asymptomatic high risk advanced adenomas and new early stage metachronous cancers. Early stage colon cancer can be defined as disease that appears to have been completely resected with no subsequent evidence of involvement of adjacent organs, lymph nodes or distant sites. This differs from the clinical setting of an apparent “curative” resection later pathologically upstaged following detection of malignant cells extending into adjacent organs, peritoneum, lymph nodes or other distant sites, including liver. This highly selected early stage colon cancer group remains at high risk for subsequent colon polyps and metachronous colon cancer. Precise staging is important, not only for assessing the need for adjuvant chemotherapy, but also for patient selection for continued surveillance. With advanced stages of colon cancer and a more guarded outlook, repeated surveillance should be limited. In future, novel imaging technologies (e.g., confocal endomicroscopy), coupled with increased pathological recognition of high risk markers for lymph node involvement (e.g., “tumor budding”) should lead to improved staging and clinical care. PMID:24379564

Freeman, Hugh James

2013-01-01

30

Effects of Vegetation, Corridor Width and Regional Land Use on Early Successional Birds on Powerline Corridors  

PubMed Central

Powerline rights-of-way (ROWs) often provide habitat for early successional bird species that have suffered long-term population declines in eastern North America. To determine how the abundance of shrubland birds varies with habitat within ROW corridors and with land use patterns surrounding corridors, we ran Poisson regression models on data from 93 plots on ROWs and compared regression coefficients. We also determined nest success rates on a 1-km stretch of ROW. Seven species of shrubland birds were common in powerline corridors. However, the nest success rates for prairie warbler (Dendroica discolor) and field sparrow (Spizella pusilla) were <21%, which is too low to compensate for estimated annual mortality. Some shrubland bird species were more abundant on narrower ROWs or at sites with lower vegetation or particular types of vegetation, indicating that vegetation management could be refined to favor species of high conservation priority. Also, several species were more abundant in ROWs traversing unfragmented forest than those near residential areas or farmland, indicating that corridors in heavily forested regions may provide better habitat for these species. In the area where we monitored nests, brood parasitism by brown-headed cowbirds (Molothrus ater) occurred more frequently close to a residential area. Although ROWs support dense populations of shrubland birds, those in more heavily developed landscapes may constitute sink habitat. ROWs in extensive forests may contribute more to sustaining populations of early successional birds, and thus may be the best targets for habitat management. PMID:22363660

Askins, Robert A.; Folsom-O'Keefe, Corrine M.; Hardy, Margaret C.

2012-01-01

31

Nitrogen concentration within Saxifraga oppositifolia in different successional stages on a glacier foreland in the high Arctic  

Microsoft Academic Search

We measured and compared the ?13C values and nitrogen concentrations within the photosynthetic parts (Np) of phototrophs growing in different successional stages and different soil conditions at Ny-Ålesund, Svalbard, Norway. At all study sites, the Np value of vascular plants ranged from 1.0 to 2.2%. The Np value for most moss species was less than 1.0%; values for lichens were

Atsushi Kume; Yukiko S. Bekku; Yuko T. Hanba; Takashi Nakano; Hiroshi Kanda

2008-01-01

32

Soil uptake of carbonyl sulfide in subtropical forests with different successional stages in south China  

NASA Astrophysics Data System (ADS)

The uptake rates of carbonyl sulfide (COS) by soils in subtropical forests with different successional stages were measured using static chambers in Dinghushan Biosphere Reserve (DBR) in south China from July 2004 to March 2005. The three typical tropical forests studied included monsoon evergreen broad-leaf forest (BF), pine and broad-leaf mixed forest (MF) and pine forest (PF), representing forests with different succession stages in the region. COS exchange rates were also compared between the plots with litter-fall remaining (plots L) and those with litter-fall removed (plots S) in each forest. Results showed that these forest soils all acted as sinks for COS with exchange rates of -1.22 to -11.82 pmol m-2 s-1. The MF in the midsuccessional stage had significantly higher uptake rates, and the mean exchange rates in the BF, MF, and PF were -3.90, -4.77, and -3.65 pmol m-2 s-1, respectively. COS uptake rates at plots L were higher than those at plots S. Mean COS fluxes were significantly higher in March (-6.06 pmol m-2 s-1) than those in July (-3.60 pmol m-2 s-1), August (-3.82 pmol m-2 s-1), September (-3.45 pmol m-2 s-1), and October (-3.54 pmol m-2 s-1). Significant correlation was observed between the COS uptake rates and soil respiration rates or microbial biomass, indicating that microbial activity was an important factor controlling the soil uptake of COS. Significant correlations between COS fluxes and initial COS mixing ratios were only observed in the BF and MF. COS fluxes showed no correlation with soil temperature or water content alone in any of the three forests, but do correlate well with soil temperature and water content together in polynomial forms with an order of 2.

Yi, Zhigang; Wang, Xinming; Sheng, Guoying; Zhang, Deqiang; Zhou, Guoyi; Fu, Jiamo

2007-04-01

33

Forest successional stage affects the cortical secondary chemistry of three old forest lichens.  

PubMed

Three epiphytic old forest lichens (Usnea longissima, Pseudocyphellaria crocata, and Lobaria pulmonaria) were transplanted along a natural shade-sun gradient comprising three successional stages in boreal spruce forests (dense young forest, open old forest, and clear-cut) for one summer. After harvest, extractable secondary compounds were analyzed by high-performance liquid chromatography, and the brown pigmentation in melanic species was quantified by reflectance measurements. Cortical compounds in all species increased from shady young forests to exposed clear-cuts. Usnic acid, the major cortical, secondary compound in U. longissima, showed consistently higher concentration in the clear-cut than in the two forested stands. Pseudocyphellaria crocata and L. pulmonaria, lacking extractable secondary compounds in the cortex, significantly increased their amounts of cortical melanins in well-lit stands. The medullary compounds showed more complex responses. Many were not influenced by environmental conditions during the transplantation, whereas the majority of those that responded showed the lowest concentration in clear-cut transplants. Only a few medullary compounds showed the highest concentration in the clear-cut, and at a low level of significance. The synthesis of UV-B-absorbing usnic acid and melanins seems to be part of an acclimation to increased light exposure. The medullary compounds in studied species barely function as solar screens despite their strong UV-B absorbance. PMID:17636451

Nybakken, Line; Asplund, Johan; Solhaug, Knut Asbjørn; Gauslaa, Yngvar

2007-08-01

34

USE OF GROUP-SELECTION AND SEED-TREE CUTS BY THREE EARLY-SUCCESSIONAL MIGRATORY SPECIES IN ARKANSAS  

Microsoft Academic Search

Silviculture in the Ouachita National Forest in Arkansas and Oklahoma has shifted in recent years from mostly even-aged management to a mix of even- and uneven-aged regeneration systems, including group-selection. Researchers have described presencelabsence of early-successional bird species in forest open- ings created by even- and uneven-aged silviculture, but few have examined nest success. We examined occu- pancy and nest

LYNN E. ALTERMAN; JAMES C. BEDNARZ; RONALD E. THILL

2005-01-01

35

Relative importance of early-successional forests and shrubland habitats to mammals in the northeastern United States  

Microsoft Academic Search

The majority of the 60 native terrestrial mammal species that reside in the northeastern United States (US) utilize resources from several habitats on a seasonal basis. However, as many as 20 species demonstrate some preference for early-successional forests, shrublands, or old-field habitats. A few of these (e.g. lagomorphs) can be considered obligate users of these habitats, and the specialist carnivores

Todd K. Fuller; Stephen DeStefano

2003-01-01

36

Genetic effects of rainforest fragmentation in an early successional tree (Elaeocarpus grandis).  

PubMed

Rainforests in Australia and around the world have been extensively cleared and degraded. It is essential to recognize the changes in population diversity and dynamics that follow habitat fragmentation if better conservation and management strategies are to be developed. This study is an investigation of the medium term (over 100 years) effects of rainforest fragmentation on a long-lived, early successional tree species within a habitat matrix that includes various types of fragmented and undisturbed sites. Five microsatellite loci were used to assess the level and distribution of genetic variation across the southern range of Elaeocarpus grandis (Elaeocarpaceae). In all, 21 sites were sampled to provide a direct comparison between fragmented and undisturbed populations. Overall levels of diversity (A=3.4, He=0.568, f=0.094) were higher than those of closely related endemic species, but lower than those recorded across other rainforest trees. No significant genetic structure was detected across this species, suggesting the existence of efficient dispersal and colonization mechanisms responsible for the maintenance of gene flow. Rainforest fragments, and in particular those within the extensively cleared Big Scrub, show a trend for increased inbreeding levels caused by a loss of heterozygosity within juvenile cohorts. However, the overall rate of genetic decline within fragmented rainforests appears to be more subtle in E. grandis than across other species. A combination of ecological attributes and evolutionary history is likely to have contributed to this outcome and need to be considered in future rainforest restoration projects. PMID:15367910

Rossetto, M; Jones, R; Hunter, J

2004-12-01

37

Nitrogen concentration within Saxifraga oppositifolia in different successional stages on a glacier foreland in the high Arctic  

NASA Astrophysics Data System (ADS)

We measured and compared the ?13C values and nitrogen concentrations within the photosynthetic parts (Np) of phototrophs growing in different successional stages and different soil conditions at Ny-Ålesund, Svalbard, Norway. At all study sites, the Np value of vascular plants ranged from 1.0 to 2.2%. The Np value for most moss species was less than 1.0%; values for lichens were about 0.5%. No significant correlation was detected between Np and ?13C; however, different plant species occupied distinct fields on a ?13C-Np plot, with minimal overlap between species. The Np value of Saxifraga oppositifolia, which grew at all of the study sites, ranged from 1.1 to 1.5%. Differences in growth form had no effect on Np. The Np and ?13C values obtained for S. oppositifolia were confined to within a narrow range regardless of site conditions.

Kume, Atsushi; Bekku, Yukiko S.; Hanba, Yuko T.; Nakano, Takashi; Kanda, Hiroshi

38

Viscosity and dissipation - early stages  

E-print Network

A very early start up time of the hydrodynamic evolution is needed in order to reproduce observations from relativistic heavy-ion collisions experiments. At such early times the systems is still not locally equilibrated. Another source of deviations from local equilibrium is the viscosity of the fluid. We study these effects at very early times to obtain a dynamical prescription for the transition from an early 2-dimensional expansion to a nearly equilibrated 3-dimensional expansion at latter stages. The role of viscosity at latter stages of the evolution is also illustrated.

P. Bozek

2009-01-15

39

Species-driven phases and increasing structure in early-successional plant communities.  

PubMed

Successional phases describe changes in ecological communities that proceed in steps rather than continuously. Despite their importance for the understanding of ecosystem development, there still exists no reliable definition of phases and no quantitative measure of phase transitions. In order to obtain these data, we investigated primary succession in an artificial catchment (6 ha) in eastern Germany over a period of 6 years. The data set consists of records of plant species and their cover values, and initial substrate properties, both from plots in a regular grid (20 m × 20 m) suitable for spatial data analysis. Community assembly was studied by analyses of species co-occurrence and nestedness. Additionally, we correlated lognormal and log series distributions of species abundance to each community. We here introduce a new general method for detection of successional phases based on the degree of transient spatial homogeneity in the study system. Spatially coherent vegetation patterns revealed nonoverlapping partitions within this sequence of primary succession and were characterized as two distinct ecological phases. Patterns of species co-occurrence were increasingly less random, and hence the importance of demographic stochasticity and neutral community assembly decreased during the study period. Our findings highlight the spatial dimension of successional phases and quantify the degree of change between these steps. They are an element for advancing a more reliable terminology of ecological successions. PMID:23234854

Zaplata, Markus K; Winter, Susanne; Fischer, Anton; Kollmann, Johannes; Ulrich, Werner

2013-01-01

40

Community Assembly of Biological Soil Crusts of Different Successional Stages in a Temperate Sand Ecosystem, as Assessed by Direct Determination and Enrichment Techniques  

Microsoft Academic Search

In temperate regions, biological soil crusts (BSCs: complex communities of cyanobacteria, eukaryotic algae, bryophytes, and\\u000a lichens) are not well investigated regarding community structure and diversity. Furthermore, studies on succession are rare.\\u000a For that reason, the community assembly of crusts representing two successional stages (initial, 5 years old; and stable,\\u000a >20 years old) were analyzed in an inland sand ecosystem in Germany in

Tanja Margrit Langhans; Christian Storm; Angelika Schwabe

2009-01-01

41

Remote sensing-based predictors improve distribution models of rare, early successional and broadleaf tree species in Utah  

USGS Publications Warehouse

1. Compared to bioclimatic variables, remote sensing predictors are rarely used for predictive species modelling. When used, the predictors represent typically habitat classifications or filters rather than gradual spectral, surface or biophysical properties. Consequently, the full potential of remotely sensed predictors for modelling the spatial distribution of species remains unexplored. Here we analysed the partial contributions of remotely sensed and climatic predictor sets to explain and predict the distribution of 19 tree species in Utah. We also tested how these partial contributions were related to characteristics such as successional types or species traits. 2. We developed two spatial predictor sets of remotely sensed and topo-climatic variables to explain the distribution of tree species. We used variation partitioning techniques applied to generalized linear models to explore the combined and partial predictive powers of the two predictor sets. Non-parametric tests were used to explore the relationships between the partial model contributions of both predictor sets and species characteristics. 3. More than 60% of the variation explained by the models represented contributions by one of the two partial predictor sets alone, with topo-climatic variables outperforming the remotely sensed predictors. However, the partial models derived from only remotely sensed predictors still provided high model accuracies, indicating a significant correlation between climate and remote sensing variables. The overall accuracy of the models was high, but small sample sizes had a strong effect on cross-validated accuracies for rare species. 4. Models of early successional and broadleaf species benefited significantly more from adding remotely sensed predictors than did late seral and needleleaf species. The core-satellite species types differed significantly with respect to overall model accuracies. Models of satellite and urban species, both with low prevalence, benefited more from use of remotely sensed predictors than did the more frequent core species. 5. Synthesis and applications. If carefully prepared, remotely sensed variables are useful additional predictors for the spatial distribution of trees. Major improvements resulted for deciduous, early successional, satellite and rare species. The ability to improve model accuracy for species having markedly different life history strategies is a crucial step for assessing effects of global change. ?? 2007 The Authors.

Zimmermann, N.E.; Edwards, T.C., Jr.; Moisen, G.G.; Frescino, T.S.; Blackard, J.A.

2007-01-01

42

Remote sensing-based predictors improve distribution models of rare, early successional and broadleaf tree species in Utah  

PubMed Central

Compared to bioclimatic variables, remote sensing predictors are rarely used for predictive species modelling. When used, the predictors represent typically habitat classifications or filters rather than gradual spectral, surface or biophysical properties. Consequently, the full potential of remotely sensed predictors for modelling the spatial distribution of species remains unexplored. Here we analysed the partial contributions of remotely sensed and climatic predictor sets to explain and predict the distribution of 19 tree species in Utah. We also tested how these partial contributions were related to characteristics such as successional types or species traits. We developed two spatial predictor sets of remotely sensed and topo-climatic variables to explain the distribution of tree species. We used variation partitioning techniques applied to generalized linear models to explore the combined and partial predictive powers of the two predictor sets. Non-parametric tests were used to explore the relationships between the partial model contributions of both predictor sets and species characteristics. More than 60% of the variation explained by the models represented contributions by one of the two partial predictor sets alone, with topo-climatic variables outperforming the remotely sensed predictors. However, the partial models derived from only remotely sensed predictors still provided high model accuracies, indicating a significant correlation between climate and remote sensing variables. The overall accuracy of the models was high, but small sample sizes had a strong effect on cross-validated accuracies for rare species. Models of early successional and broadleaf species benefited significantly more from adding remotely sensed predictors than did late seral and needleleaf species. The core-satellite species types differed significantly with respect to overall model accuracies. Models of satellite and urban species, both with low prevalence, benefited more from use of remotely sensed predictors than did the more frequent core species. Synthesis and applications. If carefully prepared, remotely sensed variables are useful additional predictors for the spatial distribution of trees. Major improvements resulted for deciduous, early successional, satellite and rare species. The ability to improve model accuracy for species having markedly different life history strategies is a crucial step for assessing effects of global change. PMID:18642470

ZIMMERMANN, N E; EDWARDS, T C; MOISEN, G G; FRESCINO, T S; BLACKARD, J A

2007-01-01

43

Early stage thermalization via instabilities  

E-print Network

Due to anisotropic momentum distributions the parton system produced at the early stage of relativistic heavy-ion collisions is unstable with respect to the magnetic plasma modes. The instabilities isotropize the system and thus speed up the process of its equilibration. The whole scenario of the instabilities driven isotropization is reviewed.

Stanislaw Mrowczynski

2006-11-06

44

Structure and diversity of Erica ciliaris and Erica tetralix heathlands at different successional stages after cutting.  

PubMed

In NW Europe, it is known that cutting is a useful tool for managers with regard to decisions about the conservation and management of wet heathlands. Nevertheless it is rarely described quantitatively in the international literature. In Spain, knowledge about this is scarce or lacking. In this study, twenty communities were selected in Galicia (NW Spain) that would represent from one to four stages of vegetation development after cutting. Two 5 × 5 m plots were established for each stage to characterise the vegetation on the basis of its species composition, frequency values, vertical structure and linear cover features. The Diversity Shannon index was calculated and multivariate analyses were performed. As succession advanced, notable changes were produced in the cover of dominant species, Erica ciliaris and Ulex gallii in the first stages and Erica tetralix and Genista berberidea in mature ones. Also, the species richness decreased because of the reduced number of herbs species in the mature stages and, finally, the cover values are indicators of the degree of vegetation development, together with the other parameters of height, overlayering or diversity. Cutting is a useful tool for management of heathlands because the existence of vegetation units belonging to different succession stages increases the internal diversity of communities. On the other hand, the vertical and horizontal structure reflects the formidable resilience of the vegetation community to this practice. This study offers a global vision of the dynamics of wet heathlands after cutting, with very useful ecological information that can be used by the people responsible for their management. PMID:21943685

Muñoz, A; García-Duro, J; Alvarez, R; Pesqueira, X M; Reyes, O; Casal, M

2012-02-01

45

Identifying genomic and metabolic features that can underlie early successional and opportunistic lifestyles of human gut symbionts  

PubMed Central

We lack a deep understanding of genetic and metabolic attributes specializing in microbial consortia for initial and subsequent waves of colonization of our body habitats. Here we show that phylogenetically interspersed bacteria in Clostridium cluster XIVa, an abundant group of bacteria in the adult human gut also known as the Clostridium coccoides or Eubacterium rectale group, contains species that have evolved distribution patterns consistent with either early successional or stable gut communities. The species that specialize to the infant gut are more likely to associate with systemic infections and can reach high abundances in individuals with Inflammatory Bowel Disease (IBD), indicating that a subset of the microbiota that have adapted to pioneer/opportunistic lifestyles may do well in both early development and with disease. We identified genes likely selected during adaptation to pioneer/opportunistic lifestyles as those for which early succession association and not phylogenetic relationships explain genomic abundance. These genes reveal potential mechanisms by which opportunistic gut bacteria tolerate osmotic and oxidative stress and potentially important aspects of their metabolism. These genes may not only be biomarkers of properties associated with adaptation to early succession and disturbance, but also leads for developing therapies aimed at promoting reestablishment of stable gut communities following physiologic or pathologic disturbances. PMID:22665442

Lozupone, Catherine; Faust, Karoline; Raes, Jeroen; Faith, Jeremiah J.; Frank, Daniel N.; Zaneveld, Jesse; Gordon, Jeffrey I.; Knight, Rob

2012-01-01

46

Response of Tridens flavus (L.) A. S. Hitchc. to soil nutrients and disturbance in an early successional old field  

USGS Publications Warehouse

Soil nutrients and disturbance are two of the main abiotic factors that influence plant dominance (canopy cover), density, and fecundity in early successional old field plant communities. The manner in which the dominant species in old field successional systems respond to the interaction of nutrients and disturbance is poorly known. We examined the dominance, density of flowering tillers, and reproductive output of Tridens flavus, a perennial, warm-season bunchgrass that is important in old field succession, to varying soil nutrient and disturbance regimes. We tested the hypothesis that the interaction between nutrients and disturbance would influence the performance (cover, density, fecundity) of T. flavus. To test this hypothesis, we subjected 25 m2 experimental plots to various combinations of fertilizer and mowing treatments for eight years after initially plowing the field. The performance of T. flavus was measured by estimating percent cover for 8 years (1996-2003) and both density of flowering tillers and reproductive output (panicle length and number of branches per panicle) for three years (2001-2003). The pattern of canopy cover of T. flavus over the first eight years of succession varied over time depending on mowing regime. Dominance was significantly higher in plots that were fertilized only in years one and five than in annually fertilized and unfertilized control plots. The length of panicles and density of flowering tillers were both significantly greater in annually mowed plots than in unmowed plots. In the absence of mowing in particular, T. flavus became overtopped by woody species and declined in this old field community. Therefore, disturbances such as mowing and fertilization may be important in maintaining grasses such as Tridens flavus in old fields.

Honu, Y.A.K.; Gibson, D.J.; Middleton, B.A.

2006-01-01

47

Early Stage of Galaxy Formation  

E-print Network

We discuss on the early stage of galaxy formation based on recent deep surveys for very high-redshift galaxies, mostly beyond redshift of 6. These galaxies are observed to be strong Lyman$\\alpha$ emitters, indicating bursts of massive star formation in them. The fraction of such star-forming system appears to increase with increasing redshift. On the other hand, the star formation rate density derived from Lyman$\\alpha$ emitters tends to decrease with increasing redshift. It is thus suggested that the major epoch of initial starbursts may occur around $z \\sim$ 6 -- 7. In order to understand the early stage of galaxy formation, new surveys for galaxies beyond redshift of 7 will be important in near future.

Y. Taniguchi; T. Nagao; M. Ajiki; Y. Shioya; S. S. Sasaki; T. Murayama

2005-10-20

48

Early stage of nanocrystal growth  

SciTech Connect

Berkeley Lab researchers at the Molecular Foundry have elucidated important mechanisms behind oriented attachment, the phenomenon that drives biomineralization and the growth of nanocrystals. This electron microscopy movie shows the early stage of nanocrystal growth. Nanoparticles make transient contact at many points and orientations until their lattices are perfectly matched. The particles then make a sudden jump-to-contact to form attached aggregates. (Movie courtesy of Jim DeYoreo)

None

2012-01-01

49

Population structure and inbreeding vary with successional stage in created Spartina alterniflora marshes  

USGS Publications Warehouse

Recruitment patterns in clonal plant populations are predicted to vary with seed dispersal capability and disturbance regime, such that species with small, widely dispersed seeds will become increasingly dominated by vegetative recruitment on disturbed areas following early colonization. Subsequent mortality due to competitive or stochastic effects is then predicted to cause a gradual decline in both clonal diversity and the ability of surviving clones to avoid geitonogamous mating and possible inbreeding depression. We tested predictions of these hypotheses by comparing four adjacent populations of the salt marsh plant, Spartina alterniflora, ranging in age from 2 to ???50 yr, by measuring fine-scale genetic structure at the level of both ramets and genets, and the rate of inbreeding. For this purpose, we sampled maternal tissue and seeds from discrete patches in the field and then genotyped both maternal and seedling tissue (germinated in a growth chamber) using standard molecular protocols. As predicted, we observed an increase in clonal diversity (measured as the complement of the Simpson Index corrected for finite sample sizes, 1-D) up to a maximum of 0.71 within 3-m2 patches at 16 yr, declining to 0.55 by ???50 yr. Local recruitment of seedlings was evident as genetic structure occurring at the level of patches, as measured by the fixation index, ??, which was inversely correlated with diversity (R2 > 0.90 at all patch scales). Outcrossing rates were positively associated with clonal diversity, with the highest level (89%) at an intermediate level of 1-D. The greatest selfing (32%) occurred in young (2-yr-old) patches with low diversity. Biparental inbreeding was minimal in all populations, never exceeding 1%. Inbreeding depression was inferred to be severe, as evidenced by near-zero adult inbreeding coefficients. These results suggest a possible fitness trade-off between clonal growth and the opportunity for outcrossing. We recommend that restoration plantings of clonal species with limited sexual recruitment capabilities should be designed to ensure adequate clonal diversity for the avoidance of inbreeding and the ability to adapt to subsequent environmental disturbances.

Travis, S.E.; Proffitt, C.E.; Ritland, K.

2004-01-01

50

Morphological and reproductive responses of dominant plant species to local conditions in herbaceous successional stages of a calcareous hillside  

Microsoft Academic Search

Secondary succession on calcareous hillsides, initiated following the abandonment of agro-pastoral practices, is characterized by the transformation of initial short sward into tall herbaceous vegetation and finally woody formations. These structural changes are accompanied by modifications in ecological conditions but some species are able to persist and flower along the successional gradient. In this study, we compare reproductive and morphological

Gaylord Dujardin; Fabrice Bureau; Thibaud Decaëns; Estelle Langlois

51

Expression analysis of candidate genes regulating successional tooth formation in the human embryo  

PubMed Central

Human dental development is characterized by formation of primary teeth, which are subsequently replaced by the secondary dentition. The secondary dentition consists of incisors, canines, and premolars, which are derived from the successional dental lamina of the corresponding primary tooth germs; and molar teeth, which develop as a continuation of the dental lamina. Currently, very little is known about the molecular regulation of human successional tooth formation. Here, we have investigated expression of three candidate regulators for human successional tooth formation; the Fibroblast Growth Factor-antagonist SPROUTY2, the Hedgehog co-receptor GAS1 and the RUNT-related transcription factor RUNX2. At around 8 weeks of development, only SPROUTY2 showed strong expression in both epithelium and mesenchyme of the early bud. During the cap stage between 12–14 weeks, SPROUTY2 predominated in the dental papilla and inner enamel epithelium of the developing tooth. No specific expression was seen in the successional dental lamina. GAS1 was expressed in dental papilla and follicle, and associated with mesenchyme adjacent to the primary dental lamina during the late cap stage. In addition, GAS1 was identifiable in mesenchyme adjacent to the successional lamina, particularly in the developing primary first molar. For RUNX2, expression predominated in the dental papilla and follicle. Localized expression was seen in mesenchyme adjacent to the primary dental lamina at the late cap stage; but surprisingly, not in the early successional lamina at these stages. These findings confirm that SPROUTY2, GAS1, and RUNX2 are all expressed during early human tooth development. The domains of GAS1 and RUNX2 are consistent with a role influencing function of the primary dental lamina but only GAS1 transcripts were identifiable in the successional lamina at these early stages of development. PMID:25484868

Olley, Ryan; Xavier, Guilherme M.; Seppala, Maisa; Volponi, Ana A.; Geoghegan, Fin; Sharpe, Paul T.; Cobourne, Martyn T.

2014-01-01

52

The Effect of Local and Landscape-Level Characteristics on the Abundance of Forest Birds in Early-Successional Habitats during the Post-Fledging Season in Western Massachusetts  

PubMed Central

Many species of mature forest-nesting birds (“forest birds”) undergo a pronounced shift in habitat use during the post-fledging period and move from their forest nesting sites into areas of early-successional vegetation. Mortality is high during this period, thus understanding the resource requirements of post-fledging birds has implications for conservation. Efforts to identify predictors of abundance of forest birds in patches of early-successional habitats have so far been equivocal, yet these previous studies have primarily focused on contiguously forested landscapes and the potential for landscape-scale influences in more fragmented and modified landscapes is largely unknown. Landscape composition can have a strong influence on the abundance and productivity of forest birds during the nesting period, and could therefore affect the number of forest birds in the landscape available to colonize early-successional habitats during the post-fledging period. Therefore, the inclusion of landscape characteristics should increase the explanatory power of models of forest bird abundance in early-successional habitat patches during the post-fledging period. We examined forest bird abundance and body condition in relation to landscape and habitat characteristics of 15 early-successional sites during the post-fledging season in Massachusetts. The abundance of forest birds was influenced by within-patch habitat characteristics, however the explanatory power of these models was significantly increased by the inclusion of landscape fragmentation and the abundance of forest birds in adjacent forest during the nesting period for some species and age groups. Our findings show that including factors beyond the patch scale can explain additional variation in the abundance of forest birds in early-successional habitats during the post-fledging period. We conclude that landscape composition should be considered when siting early-successional habitat to maximize its benefit to forest birds during the post-fledging period, and should also be included in future investigations of post-fledging habitat use by forest birds. PMID:25170610

Labbe, Michelle A.; King, David I.

2014-01-01

53

Endoscopic options for early stage esophageal cancer  

PubMed Central

Surgery has traditionally been the preferred treatment for early stage esophageal cancer. Recent advances in endoscopic treatments have been shown to be effective and safe. Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) allow endoscopists to remove small, superficial lesions, providing tumor specimen that can be examined for accurate pathologic tumor staging and assessment of adequacy of resection. Endoscopic ablation procedures, including photodynamic therapy (PDT) and radio frequency ablation (RFA), have also been shown to safely and effectively treat esophageal dysplasia and early stage neoplasia, with excellent long-term disease control. Both approaches are becoming more widely available around the world, and provide an alternative, safe, low risk strategy for treating early stage disease, making combined endoscopic therapy the recommended treatment of choice for early stage esophageal cancers. PMID:25642334

Shah, Pari M.

2015-01-01

54

Presence and Expression of Microbial Genes Regulating Soil Nitrogen Dynamics Along the Tanana River Successional Sequence  

NASA Astrophysics Data System (ADS)

We report on work to assess the functional gene sequences for soil microbiota that control nitrogen cycle pathways along the successional sequence (willow, alder, poplar, white spruce, black spruce) on the Tanana River floodplain, Interior Alaska. Microbial DNA and mRNA were extracted from soils (0-10 cm depth) for amoA (ammonium monooxygenase), nifH (nitrogenase reductase), napA (nitrate reductase), and nirS and nirK (nitrite reductase) genes. Gene presence was determined by amplification of a conserved sequence of each gene employing sequence specific oligonucleotide primers and Polymerase Chain Reaction (PCR). Expression of the genes was measured via nested reverse transcriptase PCR amplification of the extracted mRNA. Amplified PCR products were visualized on agarose electrophoresis gels. All five successional stages show evidence for the presence and expression of microbial genes that regulate N fixation (free-living), nitrification, and nitrate reduction. We detected (1) nifH, napA, and nirK presence and amoA expression (mRNA production) for all five successional stages and (2) nirS and amoA presence and nifH, nirK, and napA expression for early successional stages (willow, alder, poplar). The results highlight that the existing body of previous process-level work has not sufficiently considered the microbial potential for a nitrate economy and free-living N fixation along the complete floodplain successional sequence.

Boone, R. D.; Rogers, S. L.

2004-12-01

55

Structural and functional changes in early successional stages of a semiarid ecosystem  

SciTech Connect

The objective of our research was to study structural and functional changes that occur within and between ecosystem compartments during secondary succession in disturbed semiarid environments. First year data clearly showed an increase in resource abundance after disturbance which produced not only alteration of the soil surface but a decrease in available organic matter. In addition, marked increases in NO3 and soil water potentials were evident at all depths in the disturbed sites as compared to the undisturbed community. Soil disturbance as well as manipulation of the microflora compartment by fumigation had a significant impact on microflora structure and function. The mycorrhizal population was also drastically reduced by disturbance and fumigation. The floristic composition of the primary producers on the disturbed site was highly correlated with the propagule supply, with composition of the seed bank being the main driving force. Competition studies between bluebunch wheatgrass (Agropyron inerme), western wheatgrass, big sagebrush (Artemisia tridentata), and winterfat (Ceratoides lanata) showed that these four species were able to coexist under a wide range of water availability conditions. The final phase of an experiment designed to determine the effects of retorted shale recarbonation on plant uptake of toxic trace elements was completed. These initial studies indicate that both plant community characteristics and the presence of a functioning belowground community will be important in secondary succession processes which occur in disturbed semiarid environments. 36 figs., 41 tabs.

Redente, E.F.; Cook, C.W. (eds.)

1986-02-01

56

Acer negundo invasion along a successional gradient: early direct facilitation by native pioneers and late indirect facilitation by conspecifics.  

PubMed

*Here, we analysed the role of direct and indirect plant interactions in the invasion process of Acer negundo along a natural successional gradient in the Middle Rhone floodplain (France). We addressed two questions: What are the responses of the invasive Acer seedlings to native communities' effects along the successional gradient? What are the effects of the invasive Acer adult trees on the native communities? *In the three communities (Salix, Acer and Fraxinus stands) we transplanted juveniles of the invasive and juveniles of the natives within the forest and in experimental gaps, and with and without the herb layer. We also quantified changes in understory functional composition, light, nitrogen and moisture among treatments. *Acer seedlings were directly facilitated for survival in the Salix and Acer communities and indirectly facilitated for growth by adult Acer through the reduction of the abundance of highly competitive herbaceous competitors. *We conclude that direct facilitation by the tree canopy of the native pioneer Salix is very likely the main biotic process that induced colonization of the invasive Acer in the floodplain and that indirect facilitation by adult conspecifics contributed to population establishment. PMID:20487316

Saccone, Patrick; Pagès, Jean-Philippe; Girel, Jacky; Brun, Jean-Jacques; Michalet, Richard

2010-08-01

57

Ectomycorrhizas in vitro between Tricholoma matsutake, a basidiomycete that associates with Pinaceae, and Betula platyphylla var. japonica, an early-successional birch species, in cool-temperate forests.  

PubMed

Tricholoma matsutake is an ectomycorrhizal basidiomycete that associates with Pinaceae in the Northern Hemisphere and produces prized "matsutake" mushrooms. We questioned whether the symbiont could associate with a birch that is an early-successional species in boreal, cool-temperate, or subalpine forests. In the present study, we demonstrated that T. matsutake can form typical ectomycorrhizas with Betula platyphylla var. japonica; the associations included a Hartig net and a thin but distinct fungal sheath, as well as the rhizospheric mycelial aggregate "shiro" that is required for fruiting in nature. The in vitro shiro also emitted a characteristic aroma. This is the first report of an ectomycorrhizal formation between T. matsutake and a deciduous broad-leaved tree in the boreal or cool-temperate zones that T. matsutake naturally inhabits. PMID:25236465

Murata, Hitoshi; Yamada, Akiyoshi; Maruyama, Tsuyoshi; Neda, Hitoshi

2014-09-20

58

Treatment of early stage vocal cord carcinoma  

SciTech Connect

The cure rates for early stage vocal cord cancer are excellent with primary radiotherapy. Voice quality remains as good or becomes better than prior to treatment. For the local failures that do occur, surgical salvage will yield ultimate cure rates of about 95% for T1 and 90% for T2 tumors.

Ayers, G.

1989-03-01

59

Do natural disturbances or the forestry practices that follow them convert forests to early-successional communities?  

PubMed

Stand-replacing natural disturbances in mature forests are traditionally seen as events that cause forests to revert to early stages of succession and maintain species diversity. In some cases, however, such transitions could be an artifact of salvage logging and may increase biotic homogenization. We present initial (two-year) results of a study of the effects of tornado damage and the combined effects of tornado damage and salvage logging on environmental conditions and ground cover plant communities in mixed oak-pine forests in north central Mississippi. Plots were established in salvage-logged areas, adjacent to plots established before the storm in unlogged areas, spanning a gradient of storm damage intensity. Vegetation change directly attributable to tornado damage was driven primarily by a reduction in canopy cover but was not consistent with a transition to an early stage of succession. Although we observed post-storm increases of several disturbance indicators (ruderals), we also observed significant increases in the abundance of a few species indicative of upland forests. Increases in flowering were just as likely to occur in species indicative of forests as in species indicative of open woodlands. Few species declined as a result of the tornado, resulting in a net increase in species richness. Ruderals were very abundant in salvage-logged areas, which contained significantly higher amounts of bare ground and greater variance in soil penetrability than did damaged areas that were not logged. In contrast to unlogged areas severely damaged by the tornado, most upland forest indicators were not abundant in logged areas. Several of the forest and open-woodland indicators that showed increased flowering in damaged areas were absent or sparse in logged areas. Species richness was lower in salvage-logged areas than in adjacent damaged areas but similar to that in undamaged areas. These results suggest that salvage logging prevented positive responses of several forest and open-woodland species to tornado damage. Anthropogenic disturbances such as salvage logging appear to differ fundamentally from stand-level canopy-reducing disturbances in their effects on ground cover vegetation in the forests studied here and are perhaps more appropriately viewed as contributing to biotic homogenization than as events that maintain diversity. PMID:22611846

Brewer, J Stephen; Bertz, Christine A; Cannon, Jeffery B; Chesser, Jason D; Maynard, Erynn E

2012-03-01

60

Understanding changes in forest cover and carbon storage in early successional forests of the Pacific Northwest using USDA Forest Service FIA and multi-temporal Landsat data  

NASA Astrophysics Data System (ADS)

To effectively study dynamic processes like forest succession over long time periods one must effectively integrate data collected at many different times, locations and spatial scales. The purpose of this research is to integrate forest inventory data collected by the USDA Forest Service's Forest Inventory and Analysis (FIA) Program with multi-temporal satellite data to better understand early successional forest regrowth patterns and carbon storage in western Oregon forests. To detect and characterize continuous changes in early forest succession however, optical satellite images must first be transformed to a common radiometric scale to minimize sun, sensor, view-angle and atmospheric differences among images. We present a comparison of five atmospheric correction methods used to calibrate a nearly continuous, 20-year Landsat TM/ETM+ image data set (19-images) over western Oregon (path 46 row 29). We found that an automated ordination algorithm called multivariate alteration detection (MAD) (Canty et al., 2004), which statistically locates invariant pixels between a subject and a reference image yielded the most consistent common scale among images. Using the cross-normalized image-series we modeled percent tree cover measurements derived by ground survey and airphoto interpretation to the greater landscape. Developing a series of forest regrowth classes we identified a wide range of successional regrowth pathways 18 years after clearcut harvesting. We observed the propensity for faster regrowth on north facing aspects, shallow slopes and at low elevations. Finally, we utilized two sets of forest inventory data to evaluate a Landsat based curve-fitting model for predicting live forest carbon. At the pixel level, the model tended to over-predict carbon and performed better (i.e., higher correlation, lower RMSE) in the Coast Range ecoregion, likely the result of faster, less variable growth patterns. At the landscape scale, we found that the flux of forest carbon predicted by the curve-fit model was in absolute terms, well within the standard error of the inventory estimates. In the process of evaluating the curve-fit model, we discovered a new method for detecting subtle (i.e., forest to non-forest) land-use shifts with Landsat data. Identifying these types of land-use shifts is critically important to developing a more accurate comprehensive carbon budget from forests. We were also able to identify several potential improvements to estimating live forest carbon with the curve-fitting approach.

Schroeder, Todd A.

61

Dependence of soil respiration on soil temperature and soil moisture in successional forests in Southern China  

USGS Publications Warehouse

The spatial and temporal variations in soil respiration and its relationship with biophysical factors in forests near the Tropic of Cancer remain highly uncertain. To contribute towards an improvement of actual estimates, soil respiration rates, soil temperature, and soil moisture were measured in three successional subtropical forests at the Dinghushan Nature Reserve (DNR) in southern China from March 2003 to February 2005. The overall objective of the present study was to analyze the temporal variations of soil respiration and its biophysical dependence in these forests. The relationships between biophysical factors and soil respiration rates were compared in successional forests to test the hypothesis that these forests responded similarly to biophysical factors. The seasonality of soil respiration coincided with the seasonal climate pattern, with high respiration rates in the hot humid season (April-September) and with low rates in the cool dry season (October-March). Soil respiration measured at these forests showed a clear increasing trend with the progressive succession. Annual mean (?? SD) soil respiration rate in the DNR forests was (9.0 ?? 4.6) Mg CO2-C/hm2per year, ranging from (6.1 ?? 3.2) Mg CO2-C/hm2per year in early successional forests to (10.7 ?? 4.9) Mg CO2-C/hm2 per year in advanced successional forests. Soil respiration was correlated with both soil temperature and moisture. The T/M model, where the two biophysical variables are driving factors, accounted for 74%-82% of soil respiration variation in DNR forests. Temperature sensitivity decreased along progressive succession stages, suggesting that advanced-successional forests have a good ability to adjust to temperature. In contrast, moisture increased with progressive succession processes. This increase is caused, in part, by abundant respirators in advanced-successional forest, where more soil moisture is needed to maintain their activities. ?? 2006 Institute of Botany, Chinese Academy of Sciences.

Tang, X.-L.; Zhou, G.-Y.; Liu, S.-G.; Zhang, D.-Q.; Liu, S.-Z.; Li, J.; Zhou, C.-Y.

2006-01-01

62

Open architecture framework for improved early stage submarine design  

E-print Network

Could transparency between current disparate methods improve efficiency in early stage submarine design? Does the lack of transparency between current design methods hinder the effectiveness of early stage submarine design? ...

Sewell, Eli A. (Eli Anthony)

2010-01-01

63

15.391 Early Stage Capital, Fall 2003  

E-print Network

15.391 examines the elements of raising early stage capital, focusing on start-up ventures and the early stages of company development. This course also prepares entrepreneurs to make the best use of outside advisors, and ...

Loessberg, Shari

64

Towards the identification of early stage osteoarthritis  

PubMed Central

Summary A variety of genetic and environmental factors contribute to the progressive develop of OA. It is necessary to identify people who are developing initial changes in cartilage and/or subchondral bone before onset of classical radiological features in order to detect early phase of OA. Recent quantitative MRI techniques can evaluate the structural, mechanical and biochemical characteristics of cartilage. T2 mapping is able to assess cartilage volume and defects measurement, delayed gadolinium enhanced MRI (dGEMRIC) and Contrast Enhanced Computed Tomography (CECT) can reveal Cartilage GAG content. Accurate and reliable serum, urine and synovial fluid biomarkers are also requested. Several biomarkers have been studied and proposed, but there are many critical issues to consider for inferring useful data from studies on biomarkers in early OA such as phase of disease, specific joint sites, systemic concentrations, circadian rhythm, their clearance from the joint, etc. Recently proteomics has produced great expectations to improve the early diagnosis of OA. These discoveries may open opportunities for the identification of early stage of OA leading to manage the symptoms and ultimately slow the progression of OA. PMID:25285138

Migliore, Alberto; Massafra, Umberto

2014-01-01

65

13 CFR 107.320 - Evaluation of Early Stage SBICs.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Evaluation of Early Stage SBICs. 107.320 Section 107.320 Business...Sbic License § 107.320 Evaluation of Early Stage SBICs. SBA will evaluate an Early Stage SBIC license applicant based on the...

2013-01-01

66

13 CFR 107.320 - Evaluation of Early Stage SBICs.  

... 2014-01-01 false Evaluation of Early Stage SBICs. 107.320 Section 107.320 Business...Sbic License § 107.320 Evaluation of Early Stage SBICs. SBA will evaluate an Early Stage SBIC license applicant based on the...

2014-01-01

67

Business Model Change in Early-Stage Entrepreneurial Firms Facing High Uncertainty BUSINESS MODEL CHANGE IN EARLY-STAGE ENTREPRENEURIAL  

E-print Network

Business Model Change in Early-Stage Entrepreneurial Firms Facing High Uncertainty 1 BUSINESS MODEL Business School, U.K. Changing business models is inevitable for early-stage entrepreneurial firms striving in elements of business models in a set of eight early-stage university spin-offs. Findings suggest

Mottram, Nigel

68

Effects of above-ground browsing by mammals on mycorrhizal infection in an early successional taiga ecosystem  

Microsoft Academic Search

Using an exclosure experiment in the willow stage of primary succession on the floodplain of the Tanana River, we tested\\u000a the hypothesis that browsing can reduce mycorrhizal infection. We measured the effects winter browsing by moose (Alcesalces) and snowshoe hare (Lepusamericanus) had on mycorrhizal infection and fine root biomass of willow (Salix spp.) and balsam poplar (Populusbalsamifera). We found that

Loni J. Rossow; John P. Bryant; Knut Kielland

1997-01-01

69

Early Stages of the Natriuretic Hormone Story  

PubMed Central

The paper reviews the early stages of the research on natriuretic hormone. The described experimental work was designed and accomplished in several internationally recognized laboratories where the author was invited to extend his projects. The cross-circulation experiments in animals with acutely increased extracellular fluid volume documented, that in the mechanism of natriuresis – besides a series of the physical natriuretic factors – there is still room for an active humoral natriuretic substance. This substance inhibited the sodium transporting enzyme, Na,K-ATPase, in the frog skin. Analogous inhibition of the renal Na,K-ATPase may be partly responsible for the increased sodium excretion. It was further shown that the extent of natriuresis is positively modulated by the concentration of sodium in the cerebrospinal fluid detected in the anterior-third ventricle region (AV3V) in the brain. PMID:25426100

Lichardus, Branislav

2014-01-01

70

GENOMIC RESOURCES FOR STUDYING EARLY LIFE STAGE SALMONID HEALTH  

Technology Transfer Automated Retrieval System (TEKTRAN)

Genomic approaches are being used to study pathological and normal processes in early life stage salmonids. Early Mortality Syndrome (EMS), a disease associated with low egg thiamine levels, causes early life stage mortality and low recruitment of Great Lakes salmonids including lake trout. We use...

71

76 FR 81430 - Small Business Investment Companies-Early Stage SBICs; Public Webinars  

Federal Register 2010, 2011, 2012, 2013

...Small Business Investment Companies--Early Stage SBICs; Public Webinars AGENCY: U.S. Small...public Webinars regarding its proposed Early Stage Small Business Investment Companies (Early Stage SBIC) rule. The proposed Early Stage...

2011-12-28

72

Interactive sketching for the early stages of user interface design  

Microsoft Academic Search

Current interactive user interface construction tools are often more of a hindrance than a benefit during the early stages of user interface design. These tools take too much time to use and force designers to specify more of the design details than they wish at this early stage. Most interface designers, especially those who have a background in graphic design,

James A. Landay; Brad A. Myers

1995-01-01

73

Household Epidemics: Modelling Effects of Early Stage Vaccination  

E-print Network

Household Epidemics: Modelling Effects of Early Stage Vaccination Nyimvua ShabanÃ?,1,2 Mikael into households. A vaccination strategy, which is implemented during the early stages of the disease following is infectious and other susceptible household members are vaccinated without further delay. Expressions

Britton, Tom

74

SENSITIVITY OF RAINBOW TROUT EARLY LIFE STAGES TO NICKEL CHLORIDE  

EPA Science Inventory

Four acute tests (96-h) with juvenile fish and four early life stage tests with embryos and larvae were completed with rainbow trout (Salmo gairdneri). Ninety-six-hour flow-through LC50 values for juveniles ranged from 8.1 to 10.9 mg/l nickel. Two early life stage tests were star...

75

Growth Stages 1: Infancy and Early Childhood  

NSDL National Science Digital Library

This Science NetLinks lesson is the first of a two-part series aimed at introducing students to the different stages of physical growth and development in human beings from birth to 18 years of age. Through the use of student interactives, this lesson helps students become better aware of all the natural physical stages of growth children experience in the first five years of life.

Science Netlinks;

2003-03-29

76

Is the degree of clonality of forest herbs dependent on gap age? Using fingerprinting approaches to assess optimum successional stages for montane forest herbs  

PubMed Central

Using molecular fingerprinting (amplified fragment length polymorphism [AFLP] method), we explored the potential of small-scale population analysis for understanding colonization patterns of herb layer species in forests after canopy disturbance. We investigated three common forest understorey species with different life forms (Trientalis europaea, Calamagrostis villosa, and Vaccinium myrtillus) in the Harz Mountains in Germany in three different gap age classes and undisturbed forest. For two of them (T. europaea and C. villosa), we analyzed clone sizes and clonal structure. We hypothesized that clone sizes depend on age since gap formation and are affected by light availability. Mean patch sizes of V. myrtillus, T. europaea, and C. villosa formed were 3.7 m2, 27.9 m2, and 40.6 m2, respectively. Trientalis europaea and C. villosa patches consisted mostly of more than one genet. Largest clone sizes of T. europaea were encountered in gaps of intermediate successional age (15–60 years, averaged minimum estimation of clone sizes: 6.56 m2) whereas clone size of C. villosa was found to be independent from gap age and had a mean minimum clone size of 0.49 m2. In both species, clone size was positively related to light availability. Additionally, there was a positive relationship between clone size and ramet density for T. europaea and C. villosa. Genetic variation was higher within populations of T. europaea and C. villosa than among populations. Trientalis europaea was the only species with a clear genetic isolation by distance, pointing at an equilibrium between gene flow and genetic drift. In conclusion, we showed that forest canopy gap dynamics clearly affect the small-scale structure of populations of understorey plants. Species with high lateral growth rates, such as T. europaea offer the possibility to serve as “ecological clock” for dating ecological processes. PMID:22393501

Patsias, Kathrin; Bruelheide, Helge

2011-01-01

77

Soil nematode communities are ecologically more mature beneath late-than early-successional stage biological soil crusts  

E-print Network

genera in deserts soils and their functional role in a crust-associated food web. # 2006 Elsevier B Plateau, Utah (cool, winter rain desert) and Chihuahuan Desert, New Mexico (hot, summer rain desert) at 0­belowground link between biological soil crusts and nematode community composition is likely the increased food

Neher, Deborah A.

78

Structural dynamics of riparian forests along a black cottonwood successional gradient  

Microsoft Academic Search

Black cottonwood Populus balsamifera L. subsp. trichocarpa (Brayshaw) dominated riparian forests are important habitats for organisms in both terrestrial and aquatic ecosystems in the Pacific Northwest. Using a chronosequence approach and fixed area plots, successional processes were quantified in 28 stands along 145km of the Willamette River in Western Oregon. Cluster analysis yielded five successional stages; stand initiation, stem exclusion,

Melissa K. Fierke; J. Boone Kauffman

2005-01-01

79

Thalidomide as initial therapy for early-stage myeloma  

Microsoft Academic Search

Patients with early-stage myeloma are typically observed without therapy until symptomatic disease occurs. However, they are at high risk of progression to symptomatic myeloma, with a median time to progression of approximately 1–2 years. We report the final results of a phase II trial of thalidomide as initial therapy for early-stage multiple myeloma in an attempt to delay progression to

S V Rajkumar; M A Gertz; M Q Lacy; A Dispenzieri; R Fonseca; S M Geyer; N Iturria; S Kumar; J A Lust; R A Kyle; P R Greipp; T E Witzig

2003-01-01

80

Surgical treatment for apparent early stage endometrial cancer  

PubMed Central

Most experts would agree that the standard surgical treatment for endometrial cancer includes a hysterectomy and bilateral salpingo-oophorectomy; however, the benefit of full surgical staging with lymph node dissection in patients with apparent early stage disease remains a topic of debate. Recent prospective data and advances in laparoscopic techniques have transformed this disease into one that can be successfully managed with minimally invasive surgery. This review will discuss the current surgical management of apparent early stage endometrial cancer and some of the new techniques that are being incorporated. PMID:24596812

2014-01-01

81

Discovering colorons at the early stage LHC  

SciTech Connect

Prospects are investigated for the discovery of massive hypergluons using data from the early runs of the Large Hadron Collider. A center of mass energy of 7 TeV and an integrated luminosity of 1 fb{sup -1} or 5 fb{sup -1} are assumed. A phenomenological Lagrangian is adopted to evaluate the cross section of a pair of colored vector bosons (colorons, {rho}-tilde) decaying into four colored scalar resonances (hyperpions, {pi}-tilde), which then decay into eight gluons. The dominant eight-jet background from the production of 8g, 7g1q, 6g2q, and 5g3q is included. We find an abundance of signal events and that realistic cuts reduce the background enough to establish a 5{sigma} signal for the coloron mass of up to 733 GeV with 1 fb{sup -1} or 833 GeV with 5 fb{sup -1}.

Dicus, Duane A. [Center for Particles and Fields and Texas Cosmology Center, University of Texas, Austin, Texas 78712 (United States); Kao, Chung; Sayre, Joshua [Homer L. Dodge Department of Physics and Astronomy and Oklahoma Center for High Energy Physics, University of Oklahoma, Norman, Oklahoma 73019 (United States); Nandi, S. [Department of Physics and Oklahoma Center for High Energy Physics, Oklahoma State University, Stillwater, Oklahoma 74078 (United States)

2011-05-01

82

13 CFR 107.1182 - Valuation requirements for Early Stage SBICs based on Capital Impairment Percentage.  

Code of Federal Regulations, 2013 CFR

...false Valuation requirements for Early Stage SBICs based on Capital Impairment Percentage...Special Rules for Leverage Issued by An Early Stage Sbic § 107.1182 Valuation requirements for Early Stage SBICs based on Capital Impairment...

2013-01-01

83

13 CFR 107.1845 - Determination of Capital Impairment Percentage for Early Stage SBICs.  

...Determination of Capital Impairment Percentage for Early Stage SBICs. 107.1845 Section 107.1845 ...Determination of Capital Impairment Percentage for Early Stage SBICs. This section applies to Early Stage SBICs only. Except as modified by this...

2014-01-01

84

13 CFR 107.1180 - Required distributions to SBA by Early Stage SBICs.  

... Required distributions to SBA by Early Stage SBICs. 107.1180 Section 107.1180...Special Rules for Leverage Issued by An Early Stage Sbic § 107.1180 Required distributions to SBA by Early Stage SBICs. (a) Distribution...

2014-01-01

85

13 CFR 107.1845 - Determination of Capital Impairment Percentage for Early Stage SBICs.  

Code of Federal Regulations, 2013 CFR

...Determination of Capital Impairment Percentage for Early Stage SBICs. 107.1845 Section 107.1845 ...Determination of Capital Impairment Percentage for Early Stage SBICs. This section applies to Early Stage SBICs only. Except as modified by this...

2013-01-01

86

13 CFR 107.1181 - Interest reserve requirements for Early Stage SBICs.  

Code of Federal Regulations, 2013 CFR

...Interest reserve requirements for Early Stage SBICs. 107.1181 Section 107.1181...Special Rules for Leverage Issued by An Early Stage Sbic § 107.1181 Interest reserve requirements for Early Stage SBICs. (a) Reserve requirement....

2013-01-01

87

13 CFR 107.1180 - Required distributions to SBA by Early Stage SBICs.  

Code of Federal Regulations, 2013 CFR

... Required distributions to SBA by Early Stage SBICs. 107.1180 Section 107.1180...Special Rules for Leverage Issued by An Early Stage Sbic § 107.1180 Required distributions to SBA by Early Stage SBICs. (a) Distribution...

2013-01-01

88

13 CFR 107.1182 - Valuation requirements for Early Stage SBICs based on Capital Impairment Percentage.  

...false Valuation requirements for Early Stage SBICs based on Capital Impairment Percentage...Special Rules for Leverage Issued by An Early Stage Sbic § 107.1182 Valuation requirements for Early Stage SBICs based on Capital Impairment...

2014-01-01

89

13 CFR 107.1181 - Interest reserve requirements for Early Stage SBICs.  

...Interest reserve requirements for Early Stage SBICs. 107.1181 Section 107.1181...Special Rules for Leverage Issued by An Early Stage Sbic § 107.1181 Interest reserve requirements for Early Stage SBICs. (a) Reserve requirement....

2014-01-01

90

Definitive radiotherapy for early-stage hypopharyngeal squamous cell carcinoma.  

PubMed

The present study analyzed the outcomes of patients with early-stage hypopharyngeal squamous cell carcinoma (HPSCC) treated with radical radiotherapy (RT) or concurrent chemoradiotherapy (CCRT). We retrospectively reviewed the clinical records of 33 patients with early-stage HPSCC who underwent RT or CCRT between January 1999 and December 2011. Of the 33 patients who were treated, 12 had Stage I and 21 had Stage II disease. Patients with Stage I were typically treated with RT, while patients with Stage II were treated with CCRT (concurrent chemotherapy: 5FU, cisplatin or TS-1). The median follow-up period was 81 months, ranging from 15 to 155 months. The 5-year overall survival rates, cause specific survival rates, locoregional control rates, and progression-free survival rates were 58, 75, 56, and 49 %, respectively. Of the 33 patients, 51 % experienced second primary malignancies. Esophageal carcinoma occurred in several cases, and was diagnosed either during screening after treatment for the second primary malignancy or simultaneously with the second primary malignancy. Advanced-stage second malignancies significantly influenced the survival of the patients and the control rate for HPSCC. Treatment emphasizing the quality of life after treatment is needed, if a poor prognosis is expected because of advanced-stage second primary malignancy. PMID:24939176

Sato, Kaname; Kubota, Akira; Furukawa, Madoka; Kitani, Yousuke; Nakayama, Yuko; Nonaka, Tetsuo; Mizoguchi, Nobutaka; Shiomi, Miho

2014-06-18

91

Scaling relationships among twig size, leaf size and leafing intensity in a successional series of subtropical forests.  

PubMed

Scaling relationships among twig size, leaf size and leafing intensity fundamentally influence the twig-leaf deployment pattern, a property that affects the architecture and functioning of plants. However, our understanding of how these relationships change within a species or between species as a function of forest succession is unclear. We determined log-log scaling relationships between twig cross-sectional area (twig size) and each of total and individual leaf area, and leafing intensity (the number of leaves per twig volume) for 78 woody species along a successional series in subtropical evergreen forests in eastern China. The series included four stages: secondary shrub (S1), young (S2), sub-climax (S3) and climax evergreen broadleaved forests (S4). The scaling slopes in each of the three relationships did not differ among the four stages. The y-intercept did not shift among the successional stages in the relationship between twig cross-sectional area and total leaf area; however, the y-intercept was greatest in S4, intermediate in S3 and lowest in S2 and S1 for the relationship between twig size and individual leaf area, while the opposite pattern was found for the twig size-leafing intensity relationship. This indicates that late successional trees have few but large leaves while early successional trees have more small leaves per unit twig size. For the relationship between twig cross-sectional area and total leaf area, there was no difference in the regression slope between recurrent (appear in more than one stages) and non-recurrent species (appear in only one stage) for each of the S1-S2, S2-S3 and S3-S4 pairs. A significant difference in the y-intercept was found in the S2-S3 pair only. In the relationship between twig cross-sectional area and individual leaf area, the regression slope between recurrent and non-recurrent species was homogeneous in the S1-S2 and S3-S4 pairs, but heterogeneous in the S2-S3 pair. We conclude that forest succession caused the shift in the intercept, but did not affect scaling slopes for relationships among twig size, leaf size and leaf intensity. For recurrent species, the invariant scaling slope in the twig-leaf size relationship between adjacent pairs of successional stages may be related to their phenotypic plasticity by adjusting their twig and leaf deployment strategy to similar to what the non-recurrent species display. PMID:23824241

Yan, En-Rong; Wang, Xi-Hua; Chang, Scott X; He, Fangliang

2013-06-01

92

Impacts of a native root-rotting pathogen on successional development of old-growth Douglas fir forests  

Microsoft Academic Search

Because Pseudotsuga menziesii (Douglas fir), an early seral dominant in western Oregon forests, is particularly susceptible to the pathogenic root rot\\u000a caused by the fungus Phellinus weirii, it was hypothesized that successional development in affected forests would be accelerated. The basal area of late successional\\u000a tree species and common shrubs were compared inside and outside Phellinus weirii“infection centers”. Future successional

Jenny C. Holah; Mark V. Wilson; Everett M. Hansen

1997-01-01

93

Segmenting Gene Expression Patterns of Early-stage Drosophila Embryos  

E-print Network

Segmenting Gene Expression Patterns of Early-stage Drosophila Embryos Min-Yu Huang1,6 , Oliver R Laboratory, 1 Cyclotron Road, Berkeley CA 94720, USA MDBiggin@lbl.gov 6 Berkeley Drosophila Transcription Drosophila Transcription Network Project (BDTNP) has developed a suite of methods that support quantitative

94

Detecting Internet Worms at Early Stage Shigang Chen Sanjay Ranka  

E-print Network

1 Detecting Internet Worms at Early Stage Shigang Chen Sanjay Ranka Department of Computer of Internet economy. Arising as a leading threat, worms repetitively caused enormous damage to the Internet community during the past years. A new security service that monitors the ongoing worm activities

Chen, Shigang

95

Early developmental patterning sets the stage for brain evolution  

E-print Network

Early developmental patterning sets the stage for brain evolution Hans A. Hofmann1 Section of Texas, Austin, TX 78712 T he evolution of brain structure and function has long fascinated biologists of the brain--or brain region--and body size across a wide range of vertebrates (1). Besides random drift, two

Hofmann, Hans A.

96

Comparing Radiation Therapy Regimens for Early-Stage Breast Cancer  

Cancer.gov

In this phase III clinical trial, women with early-stage breast cancer will be randomly assigned to undergo a standard 5-week course of whole-breast irradiation (WBI) followed by a sequential boost course or 3 weeks of hypofractionated WBI with a concurrent boost.

97

TOXICITY OF AHR AGONISTS TO FISH EARLY LIFE STAGES  

EPA Science Inventory

Fish early life stages are exceptionally sensitive to the lethal toxicity of chemicals that act as arylhydrocarbon receptor (AhR) agonists. Toxicity characterizations based on 2,3,7,8-tetrachlorodibenzo-p-dioxin, generally the most potent AhR agonist, support the toxicity equiva...

98

DIAMOND CHEMICAL VAPOR DEPOSITION Nucleation and Early Growth Stages  

E-print Network

DIAMOND CHEMICAL VAPOR DEPOSITION Nucleation and Early Growth Stages by Huimin Liu David S. Dandy of high-quality diamond coatings on preshaped parts and synthesis of free-standing shapes of diamond a reality. Epi- taxial diamond has been grown on diamond and cubic-BN. Polycrystalline diamond films have

Dandy, David

99

Refining Treatment for High-risk Early Stage Endometrial Cancer  

Cancer.gov

In this clinical trial, women with high-risk early stage endometrial cancer will be randomly assigned following surgery to receive one of two types of adjuvant therapy: brachytherapy targeted to the vaginal cuff in combination with chemotherapy or standard pelvic external-beam radiotherapy.

100

Effects of ENSO and Temporal Rainfall Variation on the Dynamics of Successional Communities in Old-Field Succession of a Tropical Dry Forest  

PubMed Central

The effects of temporal variation of rainfall on secondary succession of tropical dry ecosystems are poorly understood. We studied effects of inter-seasonal and inter-year rainfall variation on the dynamics of regenerative successional communities of a tropical dry forest in Mexico. We emphasized the effects caused by the severe El Niño Southern Oscillation (ENSO) occurred in 2005. We established permanent plots in sites representing a chronosequence of Pasture (abandoned pastures, 0–1 years fallow age), Early (3–5), Intermediate (8–12), and Old-Growth Forest categories (n?=?3 per category). In total, 8210 shrubs and trees 10 to 100-cm height were identified, measured, and monitored over four years. Rates of plant recruitment, growth and mortality, and gain and loss of species were quantified per season (dry vs. rainy), year, and successional category, considering whole communities and separating seedlings from sprouts and shrubs from trees. Community rates changed with rainfall variation without almost any effect of successional stage. Mortality and species loss rates peaked during the ENSO year and the following year; however, after two rainy years mortality peaked in the rainy season. Such changes could result from the severe drought in the ENSO year, and of the outbreak of biotic agents during the following rainy years. Growth, recruitment and species gain rates were higher in the rainy season but they were significantly reduced after the ENSO year. Seedlings exhibited higher recruitment and mortality rate than sprouts, and shrubs showed higher recruitment than trees. ENSO strongly impacted both the dynamics and trajectory of succession, creating transient fluctuations in the abundance and species richness of the communities. Overall, there was a net decline in plant and species density in most successional stages along the years. Therefore, strong drought events have critical consequences for regeneration dynamics, delaying the successional process and modifying the resilience of these systems. PMID:24349179

Maza-Villalobos, Susana; Poorter, Lourens; Martínez-Ramos, Miguel

2013-01-01

101

Successional events following simazine application  

Microsoft Academic Search

Successional events of aquatic vegetation in a farm pond were studied, after application of simazine. After decay of the higher plants, phytoplankton did not dominate, instead herbicide-resistant seeds and subsurface structures of Potamogeton foliosus developed. Benthic algae covered and stabilized the bottom. Following stabilization, the water cleared and Chara vulgaris growth resumed wherever the substrate was firm.

Shirley A. Crawford

1981-01-01

102

Maternal warming affects early life stages of an invasive thistle.  

PubMed

Maternal environment can influence plant offspring performance. Understanding maternal environmental effects will help to bridge a key gap in the knowledge of plant life cycles, and provide important insights for species' responses under climate change. Here we show that maternal warming significantly affected the early life stages of an invasive thistle, Carduus nutans. Seeds produced by plants grown in warmed conditions had higher germination percentages and shorter mean germination times than those produced by plants under ambient conditions; this difference was most evident at suboptimal germination temperatures. Subsequent seedling emergence was also faster with maternal warming, with no cost to seedling emergence percentage and seedling growth. Our results suggest that maternal warming may accelerate the life cycle of this species via enhanced early life-history stages. These maternal effects on offspring performance, together with the positive responses of the maternal generation, may exacerbate invasions of this species under climate change. PMID:22404764

Zhang, R; Gallagher, R S; Shea, K

2012-03-01

103

Early-stage thymic carcinoma: is adjuvant therapy required?  

PubMed Central

Although the prognosis of advanced thymic carconoma remains poor, previous reports have shown survival rates of 70% to 100% in patients with Masaoka stage I or stage II of the disease who were treated with surgery followed by adjuvant therapy. However, the role of adjuvant therapy in these stages is controversial. We retrospectively evaluated the outcome of 4 patients with Masaoka stage II thymic carcinoma who were treated with surgery alone between 1992 and 2008. No patient had stage I of the disease. Primary tumors were preoperatively evaluated by chest X-ray and computed tomography. Needle biopsy was not performed because the tumors were clinically diagnosed as noninvasive thymomas. The largest diameter of the primary tumor was 65 mm. Mediastinal lymphadenopathy was not detected by computed tomography. All patients underwent transsternal thymectomy. Mediastinal lymph node dissection was not performed. None of the patients received adjuvant chemotherapy and/or irradiation. Histopathologic examination revealed squamous cell carcinoma in 3 patients and undifferentiated carcinoma in one. Pathologic invasion to the adjacent organs or lymph node metastasis was not detected. All patients were alive and free from relapse at a follow-up of 72 months (range, 12-167 months). Radical resection without adjuvant therapy could be a treatment option for early Masaoka stage thymic carcinoma with low-grade histology. PMID:23585943

Onuki, Takuya; Inagaki, Masaharu; Yamaoka, Masatoshi; Kitazawa, Shinsuke; Kobayashi, Keisuke; Iguchi, Kesato; Kikuchi, Shinji; Goto, Yukinobu; Onizuka, Masataka; Sato, Yukio

2013-01-01

104

Early-stage thymic carcinoma: is adjuvant therapy required?  

PubMed

Although the prognosis of advanced thymic carconoma remains poor, previous reports have shown survival rates of 70% to 100% in patients with Masaoka stage I or stage II of the disease who were treated with surgery followed by adjuvant therapy. However, the role of adjuvant therapy in these stages is controversial. We retrospectively evaluated the outcome of 4 patients with Masaoka stage II thymic carcinoma who were treated with surgery alone between 1992 and 2008. No patient had stage I of the disease. Primary tumors were preoperatively evaluated by chest X-ray and computed tomography. Needle biopsy was not performed because the tumors were clinically diagnosed as noninvasive thymomas. The largest diameter of the primary tumor was 65 mm. Mediastinal lymphadenopathy was not detected by computed tomography. All patients underwent transsternal thymectomy. Mediastinal lymph node dissection was not performed. None of the patients received adjuvant chemotherapy and/or irradiation. Histopathologic examination revealed squamous cell carcinoma in 3 patients and undifferentiated carcinoma in one. Pathologic invasion to the adjacent organs or lymph node metastasis was not detected. All patients were alive and free from relapse at a follow-up of 72 months (range, 12-167 months). Radical resection without adjuvant therapy could be a treatment option for early Masaoka stage thymic carcinoma with low-grade histology. PMID:23585943

Sakai, Mitsuaki; Onuki, Takuya; Inagaki, Masaharu; Yamaoka, Masatoshi; Kitazawa, Shinsuke; Kobayashi, Keisuke; Iguchi, Kesato; Kikuchi, Shinji; Goto, Yukinobu; Onizuka, Masataka; Sato, Yukio

2013-04-01

105

Effects of genistein on early-stage cutaneous wound healing  

SciTech Connect

Highlights: {yields} We examine the effect of genistein on cutaneous wound healing. {yields} Genistein enhanced wound closure during the early stage of wound healing. {yields} These genistein effects on wound closure were induced by reduction of oxidative stress through increasing antioxidant capacity and modulation of pro-inflammatory cytokine expression. -- Abstract: Wound healing occurs in three sequential phases: hemostasis and inflammation, proliferation, and remodeling. Inflammation, the earliest phase, is considered a critical period for wound healing because immune cells remove damaged tissues, foreign debris, and remaining dead tissue. Wound healing would be delayed without inflammation, and this phase is affected by antioxidation capacity. Therefore, we hypothesized that genistein, which has an antioxidant effect, might modulate the wound healing process by altering the inflammatory response. After three days of acclimation, mice were divided into three groups: control, 0.025% genistein, and 0.1% genistein. After two weeks of an experimental diet, skin wounds were induced. Wounded skin areas were imaged, and the healing rate calculated. To measure lipid peroxidation, antioxidant enzyme expression and activity, and pro-inflammatory cytokine expression, skin and liver tissues were harvested at 12, 24, 48, and 72 h. Genistein did not affect body weight. The rate of wound closure in mice fed genistein was significantly faster than in the control group during the early stage of wound healing, especially in first three days. Cu, Zn-SOD and Mn-SOD expression in wound skin tissue in the 0.1% genistein group was lower than in the control group. However, CAT expression did not differ among groups. We also found that genistein modulated NF-{kappa}B and TNF-{alpha} expression during the early stage of wound healing. The genistein group had significantly lower hepatic lipid peroxidation and higher SOD, CAT, and GPx activities than the control group. These results suggest that genistein supplementation reduces oxidative stress by increasing antioxidant capacity and modulating proinflammatory cytokine expression during the early stage of wound healing.

Park, Eunkyo [Department of Home Economics Education, Chung-Ang University, Seoul 156-756 (Korea, Republic of)] [Department of Home Economics Education, Chung-Ang University, Seoul 156-756 (Korea, Republic of); Lee, Seung Min [Research Institute of Health Sciences, Korea University, Seoul 136-701 (Korea, Republic of)] [Research Institute of Health Sciences, Korea University, Seoul 136-701 (Korea, Republic of); Jung, In-Kyung [Department of Home Economics Education, Chung-Ang University, Seoul 156-756 (Korea, Republic of)] [Department of Home Economics Education, Chung-Ang University, Seoul 156-756 (Korea, Republic of); Lim, Yunsook [Department of Foods and Nutrition, Kyung Hee University, Seoul 130-701 (Korea, Republic of)] [Department of Foods and Nutrition, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Kim, Jung-Hyun, E-mail: jjhkim@cau.ac.kr [Department of Home Economics Education, Chung-Ang University, Seoul 156-756 (Korea, Republic of)] [Department of Home Economics Education, Chung-Ang University, Seoul 156-756 (Korea, Republic of)

2011-07-08

106

Awareness of Memory Deficits in Early Stage Huntington's Disease  

PubMed Central

Patients with Huntington's disease (HD) are often described as unaware of their motor symptoms, their behavioral disorders or their cognitive deficits, including memory. Nevertheless, because patients with Parkinson's disease (PD) remain aware of their memory deficits despite striatal dysfunction, we hypothesize that early stage HD patients in whom degeneration predominates in the striatum can accurately judge their own memory disorders whereas more advanced patients cannot. In order to test our hypothesis, we compared subjective questionnaires of memory deficits (in HD patients and in their proxies) and objective measures of memory dysfunction in patients. Forty-six patients with manifest HD attending the out-patient department of the French National Reference Center for HD and thirty-three proxies were enrolled. We found that HD patients at an early stage of the disease (Stage 1) were more accurate than their proxies at evaluating their own memory deficits, independently from their depression level. The proxies were more influenced by patients' functional decline rather than by patients' memory deficits. Patients with moderate disease (Stage 2) misestimated their memory deficits compared to their proxies, whose judgment was nonetheless influenced by the severity of both functional decline and depression. Contrasting subjective memory ratings from the patients and their objective memory performance, we demonstrate that although HD patients are often reported to be unaware of their neurological, cognitive and behavioral symptoms, it is not the case for memory deficits at an early stage. Loss of awareness of memory deficits in HD is associated with the severity of the disease in terms of CAG repeats, functional decline, motor dysfunction and cognitive impairment, including memory deficits and executive dysfunction. PMID:23620779

Cleret de Langavant, Laurent; Fénelon, Gilles; Benisty, Sarah; Boissé, Marie-Françoise; Jacquemot, Charlotte; Bachoud-Lévi, Anne-Catherine

2013-01-01

107

Growth Stages 2: Middle Childhood and Early Adolescence  

NSDL National Science Digital Library

These lesson plans from Science NetLinks form a two-part series designed to introduce students (grades 3-5) to human growth and development from infancy through puberty. Each lesson contains detailed background information, discussion questions, and other resources that help students learn about the "key physical stages or milestones, which are research and science-supported indicators that help to track the progress of a child's physical development at different stages of life." Using these lesson plans in the classroom could prove a popular choice, as "research shows that children are fascinated by films and stories about early stages of human development and they are particularly intrigued by comparisons of themselves now and earlier." Each lesson plans comes with a comprehensive teaching guide.

108

Fertility sparing surgery in early stage epithelial ovarian cancer  

PubMed Central

Objective Fertility sparing surgery (FSS) is a strategy often considered in young patients with early epithelial ovarian cancer. We investigated the role and the outcomes of FSS in eEOC patients who underwent comprehensive surgery. Methods From January 2003 to January 2011, 24 patients underwent fertility sparing surgery. Eighteen were one-to-one matched and balanced for stage, histologic type and grading with a group of patients who underwent radical comprehensive staging (n=18). Demographics, surgical procedures, morbidities, pathologic findings, recurrence-rate, pregnancy-rate and correlations with disease-free survival were assessed. Results A total of 36 patients had a complete surgical staging including lymphadenectomy and were therefore analyzed. Seven patients experienced a recurrence: four (22%) in the fertility sparing surgery group and three (16%) in the control group (p=not significant). Sites of recurrence were: residual ovary (two), abdominal wall and peritoneal carcinomatosis in the fertility sparing surgery group; pelvic (two) and abdominal wall in the control group. Recurrences in the fertility sparing surgery group appeared earlier (mean, 10.3 months) than in radical comprehensive staging group (mean, 53.3 months) p<0.001. Disease-free survival were comparable between the two groups (p=0.422). No deaths were reported. All the patients in fertility sparing surgery group recovered a regular period. Thirteen out of 18 (72.2%) attempted to have a pregnancy. Five (38%) achieved a spontaneous pregnancy with a full term delivery. Conclusion Fertility sparing surgery in early epithelial ovarian cancer submitted to a comprehensive surgical staging could be considered safe with oncological results comparable to radical surgery group. PMID:25142621

Martinelli, Fabio; Lorusso, Domenica; Haeusler, Edward; Carcangiu, Marialuisa; Raspagliesi, Francesco

2014-01-01

109

Hypertension in Early-Stage Kidney Disease: An Update From the Kidney Early Evaluation Program (KEEP)  

Microsoft Academic Search

Background: Chronic kidney disease (CKD) is a worldwide public health problem. Systolic blood pressure as an associated feature of CKD has not been fully explored in community volunteer and nationally representative samples of the US population. Methods: This cross-sectional analysis evaluated hypertension and early-stage CKD in participants in the Kidney Early Evaluation Program (KEEP), a voluntary community-based health screening program

Rigas Kalaitzidis; Suying Li; Changchun Wang; Shu-Cheng Chen; Peter A. McCullough; George L. Bakris

2009-01-01

110

Linking forest structure and composition: avian diversity in successional forests of Chiloé Island, Chile  

Microsoft Academic Search

We show how Chilean forest bird species richness, abundance and guild structure changes as a function of structural properties of forest stands. We surveyed bird assemblages in two old-growth (>200 years), two mid-successional (30–60 years), and two early-successional forest stands (4–20 years), from November 1999 to September 2000, on Chiloé Island, southern Chile (42°S). Birds were grouped into four habitat-use

Iván A. Díaz; Juan J. Armesto; Sharon Reid; Kathryn E. Sieving; Mary F. Willson

2005-01-01

111

Point pressure sensitivity in early stage Parkinson's disease.  

PubMed

A number of sensory changes occur in the earliest stages of Parkinson's disease (PD), some of which precede the expression of the classic motor phenotype by years (e.g., olfactory dysfunction). Whether point pressure sensitivity (PPS), a cutaneous measure of light touch mediated by myelinated A? fibers, is altered in early PD is not clear. Prior studies on this point are contradictory and are based on non-forced-choice threshold tests that confound the sensitivity measure with the response criterion. While ?-synuclein pathology, a defining feature of PD, is present in the skin of PD patients, it is restricted to unmyelinated nerve fibers, suggesting PPS may be spared in this disease. We determined PPS thresholds using a state-of-the-art forced-choice staircase threshold test paradigm in 29 early stage PD patients and 29 matched controls at 11 body sites: the center of the forehead and the left and right forearms, index fingers, palms, medial soles of the feet, and plantar halluces. The patients were tested, in counterbalanced sessions, both on and off dopamine-related medications (DRMs). PPS was not influenced by PD and did not correlate with DRM l-DOPA equivalents, scores on the Unified Parkinson's Disease Rating Scale, side of the major motor disturbances, or SPECT imaging of the striatal dopamine transporter, as measured by technetium-99m TRODAT. However, PPS thresholds were lower on the left than on the right side of the body (p=0.008) and on the upper extremities relative to the toes and feet (ps<0.0001). Positive correlations were evident among the thresholds obtained across all body sectors, even though disparate regions of the body differed in terms of absolute sensitivity. This study indicates that PPS is not influenced in early stage PD regardless of whether patients are on or off DRMs. PMID:25447476

Doty, Richard L; Gandhi, Shifa S; Osman, Allen; Hurtig, Howard I; Pawasarat, Ian; Beals, Evan; Chung, Inna; Dubroff, Jacob; Newberg, Andrew; Ying, Gui-Shang; Leon-Sarmiento, Fidias E

2015-01-01

112

Cognition in the Early Stage of Type 2 Diabetes  

PubMed Central

OBJECTIVE Type 2 diabetes is known to be associated with decrements in memory and executive functions and information-processing speed. It is less clear, however, at which stage of diabetes these cognitive decrements develop and how they progress over time. In this study, we investigated cognitive functioning of patients with recent screen-detected type 2 diabetes, thus providing insight into the nature and severity of cognitive decrements in the early stage of the disease. Possible risk factors were also addressed. RESEARCH DESIGN AND METHODS Included in this study were 183 diabetic patients from a previously established study cohort and 69 control subjects. A full neuropsychological assessment, addressing six cognitive domains, was made for each participant. Raw test scores were standardized into z scores per domain and compared between the groups. Possible risk factors for cognitive decrements were examined with multivariate linear regression. RESULTS Relative to scores for the control group, mean z scores were between 0.01 and 0.2 lower in the diabetic group across all domains, but after adjustment for differences in IQ between patients and control subjects, only memory performance was significantly reduced (mean difference ?0.15 [95% CI ?0.28 to ?0.03]). A history of macrovascular disease and current smoking were significant determinants of slower information-processing speed in patients with diabetes. CONCLUSIONS This study shows that modest cognitive decrements are already present at the early stage of type 2 diabetes. A history of macrovascular disease and smoking are significant risk factors for some early decrements. PMID:19366968

Ruis, Carla; Biessels, Geert Jan; Gorter, Kees J.; van den Donk, Maureen; Kappelle, L. Jaap; Rutten, Guy E.H.M.

2009-01-01

113

Reproductive and early life stages pathology - Histopathology workshop report  

USGS Publications Warehouse

Pathology occurring during reproduction and larval development represents an important part of the life cycle of fish, and the diseases that affect eggs and larvae often result in significant losses. However, mortality during this period is frequently ignored or poorly researched as the temptation is to replace the losses rather than investigate the causes. A histopathology workshop organised at the newly refurnished laboratory within the Danish Veterinary School was an opportunity to discuss the pathology of selected diseases associated with Reproductive and Early Life Stages Pathology. Several people also kindly provided reference slides.

Bruno, D.W.; Nowak, B.; Elliott, D.G.

2006-01-01

114

Early intensification treatment approach in advanced-stage Hodgkin lymphoma.  

PubMed

The key question in advanced-stage Hodgkin lymphoma for many years now has been, should intensified chemotherapy be applied upfront or be reserved for relapsing patients. The early intensification approach with BEACOPP(escalated) (bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, prednisone) aims at curing patients with first-line chemotherapy definitely. The added toxicity of this approach as compared to less intensive regimens as ABDV (doxorubicin, bleomycin, dacarbazine, vinblastine) is mainly restricted to acute haematotoxicity and gonadal damage. However, regarding efficacy, there is a meaningful survival-benefit over ABVD (10% at 5years) and the intensified first-line treatment strategy is thus rightly regarded as standard of care. PMID:24287068

Borchmann, Peter

2014-02-01

115

Changes in microbial heterotrophic diversity along five plant successional sequences  

Microsoft Academic Search

Little is known about the changes in microbial diversity associated with ecosystem development. We measured microbial heterotrophic evenness (a component of diversity) and other soil\\/humus properties (including basal respiration, substrate-induced respiration, pH, total C, N and P) at different stages in the development of five different ecosystems, with plant assemblages being used to define the phase in the successional sequence.

L. A Schipper; B. P Degens; G. P Sparling; L. C Duncan

2001-01-01

116

13 CFR 107.565 - Restrictions on third-party debt of Early Stage SBICs.  

...false Restrictions on third-party debt of Early Stage SBICs. 107.565 Section 107.565 Business...565 Restrictions on third-party debt of Early Stage SBICs. If you are an Early Stage SBIC and you have outstanding Leverage or...

2014-01-01

117

13 CFR 107.565 - Restrictions on third-party debt of Early Stage SBICs.  

Code of Federal Regulations, 2013 CFR

...false Restrictions on third-party debt of Early Stage SBICs. 107.565 Section 107.565 Business...565 Restrictions on third-party debt of Early Stage SBICs. If you are an Early Stage SBIC and you have outstanding Leverage or...

2013-01-01

118

Contribution of defect on early stage of LIPSS formation.  

PubMed

We investigated an early stage of laser-induced periodic surface structure (LIPSS) formation to elucidate the contribution of defects on the formation. 4H-SiC crystals were irradiated by multiple pulses of femtosecond laser with different laser spot sizes. We observed the decrease in formation thresholds of high-spatial-frequency LIPSS (HSFL) and low-spatial-frequency LIPSS (LSFL) with the increased irradiated laser spot size. For smaller laser spot size, HSFL was only formed at the periphery of LSFL formation area, whereas for larger spot size, HSFL was randomly distributed within the laser spot. Our results are coincident with the hypothesis that the existence of defects in crystal contributes to the early stage on the formation of LIPSS, in which the electron excitation via one or two photon absorption in a defect site cause local nanoablation at a laser fluence under the intrinsic ablation threshold, followed by the formation of a nanovoid, which act as a scatterer, and interference of scattered wave and laser pulses lead to HSFL formation. PMID:25089418

Shimizu, Hisashi; Yada, Shuhei; Obara, Go; Terakawa, Mitsuhiro

2014-07-28

119

Effects of hydroelectric turbine passage on fish early life stages  

SciTech Connect

Turbine-passage mortality has been studied extensively for juveniles and adults of migratory fish species, but few studies have directly quantified mortality of fish eggs and larvae. An analysis of literature relating to component stresses of turbine passage (i.e., pressure changes, blade contact, and shear) indicates that mortality of early life stages of fish would be relatively low at low-head, bulb turbine installations. The shear forces and pressure regimes normally experienced are insufficient to cause high mortality rates. The probability of contact with turbine blades is related to the size of the fish; less than 5% of entrained ichthyoplankton would be killed by the blades in a bulb turbine. Other sources of mortality (e.g., cavitation and entrainment of fish acclimated to deep water) are controlled by operation of the facility and thus are mitigable. Because turbine-passage mortality among fish early life stages can be very difficult to estimate directly, it may be more fruitful to base the need for mitigation at any given site on detailed knowledge of turbine characteristics and the susceptibility of the fish community to entrainment. 7 refs., 1 fig.

Cada, G.F.

1991-01-01

120

Experimental Study of the Early Stages of Dendritic Growth  

NASA Astrophysics Data System (ADS)

Recent theoretical and computational advances(Nikolas Provatas, Nigel Goldenfeld, and Jonathan Dantzig, Phys Rev. Lett.), 80, 3308 (1998); Alain Karma and Wouter-Jan Rappel, Phys. Rev. E, 60, 3614 (1999). have allowed more careful study of the early stages of dendritic crystal growth that go beyond steady state approximations and include time-dependent growth and sidebranching in a realistic way. Recent experiments(J.C. LaCombe, M.B. Koss, and M.E. Glicksman, Phys. Rev. Lett.), 83, 2997 (1999) also suggest a re-examination of the steady-state approach may be in order. I will describe experiments designed to study the very early stages of dendritic crystal growth. Starting with an initially spherical seed, we slowly lower the temperature and record the development of the initial dendrite tips, the initial development of sidebranches, and the approach towards steady state. Further details are available online at http://www.lafayette.edu/ doughera/talks/aps2000/.

Dougherty, Andrew

2000-03-01

121

Early stages during plasma nitriding of pure iron  

SciTech Connect

The sequence of nitride formation during the early stages of plasma nitriding of pure iron was studied by optical microscopy, SEM, TEM and x-ray diffraction. Plasma nitriding at {approximately}490 C in a 25 vol.%H{sub 2} + 75 vol.%N{sub 2} mixture starts with the formation of {gamma}{prime}-Fe{sub 4}N after 40s. Once {gamma}{prime} nucleates, it mainly spreads laterally due to diffusion shortcuts in the discontinuous surface nitride layer. Before {gamma}{prime} is continuous on the surface, {epsilon} nucleates on top of it shortly after 40S. Epsilon is then observed to grow, both inwardly and laterally along with {gamma}{prime}. A compact {gamma}{prime}/{epsilon} bilayer forms on the surface at around 100s. The kinetics of nucleation, growth and compactation of the nitrides observed in the present work was significantly more rapid than in any of the nitriding process reported in the literature, including plasma nitriding. The acceleration of the nitriding kinetics in the early stages of plasma nitriding may be attributed to enhanced diffusion resulting from a high nitrogen flux from the plasma atmosphere. The results presented are consistent with the findings of a companion work on modeling the kinetics of nitride layer growth.

Palacios, M.D.; Martinez, O.; Oseguera, J. [Inst. Tecnologico y de Estudiuos Superiores de Monterrey, Atizapan (Mexico)

1995-12-31

122

Cryoablation of Early-Stage Primary Lung Cancer  

PubMed Central

Worldwide, lung cancer is the most commonly diagnosed cancer, and lobectomy is the gold-standard treatment for early-stage non-small cell lung cancer (NSCLC). However, many patients are poor surgical candidates for various reasons. Recently, image-guided ablation is being used for lung tumors. Cryoablation has been applied for the treatment of cancer in various nonaerated organs; recently it has been adapted to the treatment of lung tumors. Since an ice ball can be detected by computed tomography (CT), cryoablation of lung tumors is performed under CT guidance. Its first clinical application was reported in 2005, and it has been reported to be feasible in a few studies. Minor complications occurred at a high frequency (up to 70.5%), but major complications were rare (up to 1%). The most common complication is pneumothorax, and most cases need no further intervention. Local efficacy depends on tumor size and presence of a thick vessel close to the tumor. Midterm survival after cryoablation is 77%–88% at 3 years in patients with early-stage NSCLC. Although surgery is the gold-standard treatment for such patients, the initial results of cryoablation are promising. In this paper, the current status of cryoablation for primary lung tumors is reviewed. PMID:24991559

Nakatsuka, Seishi; Jinzaki, Masahiro

2014-01-01

123

Metamorphic density controls on early-stage subduction dynamics  

NASA Astrophysics Data System (ADS)

Subduction is primarily driven by the densification of the downgoing oceanic slab, due to dynamic P-T-fields in subduction zones. It is crucial to unravel slab densification induced by metamorphic reactions to understand the influence on plate dynamics. By analyzing the density and metamorphic structure of subduction zones, we may gain knowledge about the driving, metamorphic processes in a subduction zone like the eclogitization (i.e., the transformation of a MORB to an eclogite), the breakdown of hydrous minerals and the release of fluid or the generation of partial melts. We have therefore developed a 2D subduction zone model down to 250 km that is based on thermodynamic equilibrium assemblage computations. Our model computes the "metamorphic density" of rocks as a function of pressure, temperature and chemical composition using the Theriak-Domino software package at different time stages. We have used this model to investigate how the hydration, dehydration, partial melting and fractionation processes of rocks all influence the metamorphic density and greatly depend on the temperature field within subduction systems. These processes are commonly neglected by other approaches (e.g., gravitational or thermomechanical in nature) reproducing the density distribution within this tectonic setting. The process of eclogitization is assumed as being important to subduction dynamics, based on the very high density (3.6 g/cm3) of eclogitic rocks. The eclogitization in a MORB-type crust is possible only if the rock reaches the garnet phase stability field. This process is primarily temperature driven. Our model demonstrates that the initiation of eclogitization of the slab is not the only significant process that makes the descending slab denser and is responsible for the slab pull force. Indeed, our results show that the densification of the downgoing lithospheric mantle (due to an increase of pressure) starts in the early subduction stage and makes a significant contribution to the slab pull, where eclogitization does not occur. Thus, the lithospheric mantle acts as additional ballast below the sinking slab shortly after the initiation of subduction. Our calculation shows that the dogma of eclogitized basaltic, oceanic crust as the driving force of slab pull is overestimated during the early stage of subduction. These results improve our understanding of the force budget for slab pull during the intial and early stage of subduction. Therefore, the complex metamorphic structure of a slab and mantle wedge has an important impact on the development and dynamics of subduction zones. Further Reading: Duesterhoeft, Oberhänsli & Bousquet (2013), submitted to Earth and Planetary Science Letters

Duesterhoeft, Erik; Oberhänsli, Roland; Bousquet, Romain

2013-04-01

124

Gene Expression Profiling for Early-stage NSCLC.  

PubMed

Lung cancer is the leading cause of cancer-related death in both developed and developing countries with unacceptably high mortality even for early-stage cancers. Present guidelines do not recommend adjuvant chemotherapy for stage I non-small cell lung carcinoma and prompts a search for a prognostic marker that would separate stage I patients into 2 groups, those who would benefit and those who would not benefit from adjuvant treatment. Studies during the last decade showed that the gene expression profiling can be the biomarker being sought. Many gene expression profiling have been found and reported from the analysis of surgical specimens of resected lung cancers during the last decade, and many of them had been shown to have an excellent predictive accuracy. These profiles used in the studies had not only different gene combinations but also different number of genes and methods of identification. Researchers have used microarray assays, RT-quantitative polymerase chain reaction, and more recently microRNA-based techniques to achieve this goal. Unfortunately, most of the profiles were not sufficiently validated and/or were not used in prospective phase III studies. This review focuses on major studies in the field, future prospects, as well as the lessons learned so far. It is shown that the gene expression profiles have a good chance of being implemented in future everyday practice. PMID:23608827

Petrosyan, Frunze; Daw, Hamed; Haddad, Abdo; Spiro, Timothy; Sood, Ruchi

2015-02-01

125

Model atmospheres for novae during the early stages  

SciTech Connect

Continuum and line blanketing models for the photospheres of novae in the early stages of their outbursts are presented. The expanding envelopes are characterized by a very slow increase of density with decreasing radius which leads to very large geometrical extensions and large temperature differences between the inner and outer parts. The spectra show a large IR excess and a small Balmer jump which may be either in absorption or in emission. For the parameters considered (T{sub eff} = 10{sup 4}, 1.5 {times} 10{sup 4}, 2 {times} 10{sup 4}K, R = 10{sup 11} cm, solar composition), most lines are in absorption. The effects of both modifications in the temperature structure (e.g. by heating from shock fronts) and changes in the abundances of the heavy elements on the emergent spectra are briefly discussed. 13 refs., 11 figs.

Wehrse, R.; Hauschildt, P.H. (Heidelberg Univ. (Germany, F.R.). Inst. fuer Theoretische Astrophysik); Shaviv, G. (Technion-Israel Inst. of Tech., Haifa (Israel). Dept. of Physics); Starrfield, S. (Los Alamos National Lab., NM (USA) Arizona State Univ., Tempe, AZ (USA). Dept. of Physics)

1989-01-01

126

Early stage differentiation of thallus cells of Porphyra haitanensis (Rhodophyta)  

NASA Astrophysics Data System (ADS)

The early stage differentiation of thallus cells of Porphyra haitanensis T. J. Chang et B. F. Zheng was studied. Protoplasts or single cells were isolated from the blades using enzyme mixture comprising 2% sea snail gut enzyme and 1% cellulase. The isolated protoplasts or single cells were incubated in the MES medium. The cell differentiations were examined under the microscope at intervals after incubation. Four types of cell differentiation, namely, normal, abnormal, carposporangial and spermatorangial, and rhizoidal types, were observed. Since normal cell differentiations occur mostly in small thalli 50 mm in length and middle portions of big thalli 200 mm in length, it is essential to select tissues from these two kinds of thalli essential for commercial production.

Wang, Sujuan; Sun, Yunlong; Lu, Anming; Wang, Guangyuan

1987-09-01

127

Frontiers in radiotherapy for early-stage invasive breast cancer.  

PubMed

The development of breast-conserving treatment for early-stage breast cancer is one of the most important success stories in radiation oncology in the latter half of the twentieth century. Lumpectomy followed by radiotherapy provides an appealing alternative to mastectomy for many women. In recent years, there has been a shift in clinical investigational focus toward refinements in the methods of delivering adjuvant radiotherapy that provide shorter, more convenient schedules of external-beam radiotherapy and interstitial treatment. Expedited courses of whole-breast treatment have been demonstrated to be equivalent to traditional lengthier courses in terms of tumor control and cosmetic outcome and to provide an opportunity for cost efficiencies. PMID:25113764

Fisher, Christine M; Rabinovitch, Rachel

2014-09-10

128

Generic Difference Between Early and Late Stages of BATSE Gamma-Ray Bursts  

NASA Technical Reports Server (NTRS)

The early and late stages of gamma-ray bursts are studied in a statistical analysis of the large sample of long BATSE events. The primary peak is used as the boundary between the early and late stages of emission. Significant differences are found between the stages: the early stage is shorter, it has harder emission, and it becomes a smaller fraction of the total burst duration for burst groups of decreasing intensity.

Mitrofanov, Igor G.; Litvak, Maxim L.; Anfimov, Dimitrij S.; Sanin, Anton B.; Briggs, Michael S.; Paciesas, William S.; Pendleton, Geoffrey N.; Preece, Robert D.; Meegan, Charles A.

2001-01-01

129

Late effects of treatment for early-stage Hodgkin's disease.  

PubMed Central

A comprehensive survey of late effects (physical, social and reproductive) following treatment at a single institution for early stage Hodgkin's disease (HD) was performed. A total of 611 patients with stage I and II HD treated between 1973 and 1984 were reviewed; 460 were alive and were mailed a self-reported questionnaire. A total of 363 (79%) replies were received. Twenty patients died of second malignancy, 14 of heart disease and nine from respiratory disease. There were 37 cases of second malignancy [relative risk (RR) 2.2, absolute excess risk (AR) 35.8]. The 15-year incidence of heart disease was 11% and there were nine myocardial infarction deaths (RR 1.55, AR 5.4). Twenty-eight (8%) respondents stated that their career had been greatly interfered with, 53 (14.5%) perceived financial loss. Sexual activity was disrupted in 25.8%. In total, 56 men had fathered 112 pregnancies. Of 171 women, 40.3% became pregnant, resulting in 92 live births. A total of 43 men and 16 women had sought medical advice with regard to infertility. PMID:9579837

Brierley, J. D.; Rathmell, A. J.; Gospodarowicz, M. K.; Sutcliffe, S. B.; Munro, A.; Tsang, R.; Pintilie, M.

1998-01-01

130

Simulations of nucleation and early growth stages of protein crystals.  

PubMed Central

Analysis of known protein crystal structures reveals that interaction energies between monomer pairs alone are not sufficient to overcome entropy loss related to fixing monomers in the crystal lattice. Interactions with several neighbors in the crystal are required for stabilization of monomers in the lattice. A microscopic model of nucleation and early growth stages of protein crystals, based on the above observations, is presented. Anisotropy of protein molecules is taken into account by assigning free energies of association (proportional to the buried surface area) to individual monomer-monomer contacts in the lattice. Lattice simulations of the tetragonal lysozyme crystal based on the model correctly reproduce structural features of the movement of dislocation on the (110) crystal face. The dislocation shifts with the speed equal to the one determined experimentally if the geometric probability of correct orientation is set to 10(-5), in agreement with previously published estimates. At this value of orientational probability, the first nuclei, the critical size of which for lysozyme is four monomers, appear in 1 ml of supersaturated solution on a time scale of microseconds. Formation of the ordered phase proceeds through the growth of nuclei (rather then their association) and requires nucleations on the surface at certain stages. Images FIGURE 2 PMID:9251778

Kierzek, A M; Wolf, W M; Zielenkiewicz, P

1997-01-01

131

Modeling TGF-? in Early Stages of Cancer Tissue Dynamics  

PubMed Central

Recent works have highlighted a double role for the Transforming Growth Factor (-): it inhibits cancer in healthy cells and potentiates tumor progression during late stage of tumorigenicity, respectively; therefore it has been termed the “Jekyll and Hyde” of cancer or, alternatively, an “excellent servant but a bad master”. It remains unclear how this molecule could have the two opposite behaviours. In this work, we propose a - multi scale mathematical model at molecular, cellular and tissue scales. The multi scalar behaviours of the - are described by three coupled models built up together which can approximatively be related to distinct microscopic, mesoscopic, and macroscopic scales, respectively. We first model the dynamics of - at the single-cell level by taking into account the intracellular and extracellular balance and the autocrine and paracrine behaviour of -. Then we use the average estimates of the - from the first model to understand its dynamics in a model of duct breast tissue. Although the cellular model and the tissue model describe phenomena at different time scales, their cumulative dynamics explain the changes in the role of - in the progression from healthy to pre-tumoral to cancer. We estimate various parameters by using available gene expression datasets. Despite the fact that our model does not describe an explicit tissue geometry, it provides quantitative inference on the stage and progression of breast cancer tissue invasion that could be compared with epidemiological data in literature. Finally in the last model, we investigated the invasion of breast cancer cells in the bone niches and the subsequent disregulation of bone remodeling processes. The bone model provides an effective description of the bone dynamics in healthy and early stages cancer conditions and offers an evolutionary ecological perspective of the dynamics of the competition between cancer and healthy cells. PMID:24586338

Ascolani, Gianluca; Liò, Pietro

2014-01-01

132

Sentinel lymph node navigation surgery for early stage gastric cancer  

PubMed Central

We attempted to evaluate the history of sentinel node navigation surgery (SNNS), technical aspects, tracers, and clinical applications of SNNS using Infrared Ray Electronic Endoscopes (IREE) combined with Indocyanine Green (ICG). The sentinel lymph node (SLN) is defined as a first lymph node (LN) which receives cancer cells from a primary tumor. Reports on clinical application of SNNS for gastric cancers started to appear since early 2000s. Two prospective multicenter trials of SNNS for gastric cancer have also been accomplished in Japan. Kitagawa et al reported that the endoscopic dual (dye and radioisotope) tracer method for SN biopsy was confirmed acceptable and effective when applied to the early-stage gastric cancer (EGC). We have previously reported the usefulness of SNNS in gastrointestinal cancer using ICG as a tracer, combined with IREE (Olympus Optical, Tokyo, Japan) to detect SLN. LN metastasis rate of EGC is low. Hence, clinical application of SNNS for EGC might lead us to avoid unnecessary LN dissection, which could preserve the patient’s quality of life after operation. The most ideal method of SNNS should allow secure and accurate detection of SLN, and real time observation of lymphatic flow during operation. PMID:24914329

Mitsumori, Norio; Nimura, Hiroshi; Takahashi, Naoto; Kawamura, Masahiko; Aoki, Hiroaki; Shida, Atsuo; Omura, Nobuo; Yanaga, Katsuhiko

2014-01-01

133

Alpha Oscillations and Early Stages of Visual Encoding  

PubMed Central

For a long time alpha oscillations have been functionally linked to the processing of visual information. Here we propose an new theory about the functional meaning of alpha. The central idea is that synchronized alpha reflects a basic processing mode that controls access to information stored in a complex long-term memory system, which we term knowledge system in order to emphasize that it comprises not only declarative memories but any kind of knowledge comprising also procedural information. Based on this theoretical background, we assume that during early stages of perception, alpha “directs the flow of information” to those neural structures which represent information that is relevant for encoding. The physiological function of alpha is interpreted in terms of inhibition. We assume that alpha enables access to stored information by inhibiting task-irrelevant neuronal structures and by timing cortical activity in task relevant neuronal structures. We discuss a variety findings showing that evoked alpha and phase locking reflect successful encoding of global stimulus features in an early post-stimulus interval of about 0–150?ms. PMID:21687470

Klimesch, Wolfgang; Fellinger, Robert; Freunberger, Roman

2011-01-01

134

[Embryo-fetal development in the early stages of pregnancy].  

PubMed

The introduction of high resolution transvaginal US in obstetrical clinical practice permits earlier and more detailed visualization of embryo-fetal structures in early pregnancy. A transvaginal US examination with a high-resolution probe (5.0-6.0 MHz) was performed in 1246 pregnant patients between 9 and 16 weeks of gestation and known gestational age. Ten embryo-fetal biometric parameters were measured (crown-rump length, biparietal diameter, head circumference, transverse cerebellar diameter, thoracic circumference, mean abdominal diameter, abdominal circumference, femur length, humerus length and foot length). Reference ranges with 5 degrees and 95 degrees percentile intervals were constructed for all biometric parameters in relation to gestational age. Only one scan per patient was considered for this study. All the parameters evaluated demonstrated a high correlation with gestational age at polynomial regression analysis. The mean coefficient of determination (r2) ranged from 97.15 for biparietal diameter to 88.17 for transverse cerebellar diameter. The data are useful as reference range for the assessment of normal embryofetal development by transvaginal US in the early stages of pregnancy. PMID:9280943

Guariglia, L; Rosati, P

1997-05-01

135

Early-stage compositional segregation in polymer-blend films * J. F. Douglas,2  

E-print Network

Early-stage compositional segregation in polymer-blend films H. Wang,1, * J. F. Douglas,2 S. K and the slow dynamics of polymers near their glass transition, we investigate this early-stage surface compositional enrichment in a phase sepa- rating polymer blend for the first time. Two stages of surface

Wang, Howard "Hao"

136

Reclassification of early stage pulmonary adenocarcinoma and its consequences  

PubMed Central

The classification of pulmonary adenocarcinoma has recently undergone several proposed changes. Among these, the most striking pertains to the discontinuation of the term “bronchioloalveolar carcinoma (BAC)” and its replacement by the terms “adenocarcinoma in situ (AIS)” or “minimally invasive adenocarcinoma (MIA)” for small solitary adenocarcinomas with either pure bronchiolalveolar growth or predominant bronchioloalveolar growth and ?5 mm invasion, respectively, in resection specimens. The recommendation for these new concepts was based on discussion and review of the literature by a panel of experts from multiple disciplines. However, the results of a recent study investigating the topic of early stage adenocarcinoma (pT1N0M0) which was based on an actual series of cases, have raised questions as to the concept, validity and justification of such new terminology and have reinforced the need to evaluate actual cases that meet the newly proposed definitions and compare them in terms of patient outcome. This is even more important when proposing terminology that implies benign behavior and that could result in a false sense of security putting patients at risk for suboptimal treatment approaches. The controversies surrounding these issues are the subject of this work. PMID:25349709

Moran, Cesar A.

2014-01-01

137

Clinical therapeutic strategies for early stage of diabetic kidney disease  

PubMed Central

Diabetic kidney disease (DKD) is the most common cause of chronic kidney disease, leading to end-stage renal disease and cardiovascular disease. The overall number of patients with DKD will continue to increase in parallel with the increasing global pandemic of type 2 diabetes. Based on landmark clinical trials, DKD has become preventable by controlling conventional factors, including hyperglycemia and hypertension, with multifactorial therapy; however, the remaining risk of DKD progression is still high. In this review, we show the importance of targeting remission/regression of microalbuminuria in type 2 diabetic patients, which may protect against the progression of DKD and cardiovascular events. To achieve remission/regression of microalbuminuria, several steps are important, including the early detection of microalbuminuria with continuous screening, targeting HbA1c < 7.0% for glucose control, the use of renin angiotensin system inhibitors to control blood pressure, the use of statins or fibrates to control dyslipidemia, and multifactorial treatment. Reducing microalbuminuria is therefore an important therapeutic goal, and the absence of microalbuminuria could be a pivotal biomarker of therapeutic success in diabetic patients. Other therapies, including vitamin D receptor activation, uric acid-lowering drugs, and incretin-related drugs, may also be promising for the prevention of DKD progression. PMID:24936255

Kitada, Munehiro; Kanasaki, Keizo; Koya, Daisuke

2014-01-01

138

Leukocyte emigration in the early stages of laminitis.  

PubMed

The mechanisms that initiate the pathophysiologic changes in the digital laminae in equine laminitis are poorly understood. Due to the fact that (1) the horse at risk of laminitis has many similarities clinically to the human sepsis patient and (2) our recent finding of marked laminar proinflammatory cytokine expression at the developmental time point of the black walnut extract (BWE) model of laminitis, we tested the possibility that, similar to organ damage in human sepsis, leukocyte emigration is an early event in laminitis. Using immunoperoxidase methods with an anti-equine CD13 monoclonal antibody that recognizes neutrophils and monocytes, we discovered that, whereas the dermal microvasculature of the skin commonly has a marginal pool of leukocytes, the normal laminar dermal microvasculature has minimal to no perivascular leukocytes. However, increases in leukocyte numbers occurred around the dermal vasculature of both the laminae and the skin in the majority of BWE-treated horses in the developmental stage and at the onset of clinical signs of lameness in the BWE model. These findings indicate that, similar to organ failure in human sepsis, leukocyte emigration is likely to play a significant role in initiating numerous pathophysiologic mechanisms that lead to the development of laminitis. PMID:16169600

Black, Samuel J; Lunn, D Paul; Yin, Cailing; Hwang, Misako; Lenz, Stephen D; Belknap, James K

2006-01-15

139

Nutrient fluxes in litterfall of a secondary successional alluvial rain forest in Southern Brazil.  

PubMed

During forest succession, litterfall nutrient fluxes increase significantly. The higher inputs of organic matter and nutrients through litterfall affects positively soil fertility and the species composition, which are essential components in forest restoration and management programs. In the present study, the input of nutrients to the forest soil via litterfall components was estimated for two sites of different development stages, in an early successional alluvial rain forest in Brazil. Litterfall returned to the soil, in kg/ha, ca. 93 N, 79 Ca, 24 K, 15 Mg, 6 P, 1.7 Mn, 0.94 Fe, 0.18 Zn, 0.09 Cu and 11.2 Al, in the site where trees were more abundant and had higher values of basal area. In the other area, where trees where less abundant and values of basal area were comparatively low, litterfall returned < 50% of those amounts to the forest soil, except for Al. The amount of Al that returned to the soil was similar in both areas due to the high contribution of Tibouchina pulchra (82% of Al returned). Comparatively, high proportion of three dominant native tree species (Myrsine coriacea, T. pulchra and Cecropia pachystachya) explained better litter nutrient use efficiency (mainly N and P) in the site with the least advanced successional stage. Although litterfall of these species show lower nutrient concentrations than the other tree species, their nutrient fluxes were high in both sites, indicating a certain independence from soil essential nutrients. Such feature of the native species is very advantageous and should be considered in forest restoration programs. PMID:22208099

Scheer, Maurício Bergamini; Gatti, Gustavo; Wisniewski, Celina

2011-12-01

140

Use of regenerating clearcuts by late-successional bird species and their young during the post-fledging period  

Microsoft Academic Search

From 1995 to 1999, we mist-netted birds in regenerating clearcuts within a primarily forested landscape of West Virginia and Virginia to determine the extent that both resident and migrant birds and their young use this type of early-successional habitat during the post-fledging period. Our primary objective was to document whether or not birds typically considered mature or late-successional forest breeders

Matthew R. Marshall; Jennifer A. DeCecco; Alan B. Williams; George A. Gale; Robert J. Cooper

2003-01-01

141

Ameliorating Patient-Caregiver Stigma in Early-Stage Parkinson's Disease using Robot co-Mediators  

E-print Network

Ameliorating Patient-Caregiver Stigma in Early-Stage Parkinson's Disease using Robot co-Mediators Ronald C. Arkin Abstract. Facial masking in early stage Parkinson's disease leads to a well that are able to express affective state through kinesics and proxemics. 1 INTRODUCTION Parkinson's disease

142

TOXICITY OF TRIVALENT CHROMIUM TO EARLY LIFE STAGES OF STEELHEAD TROUT  

EPA Science Inventory

Acute and early life stage toxicity tests were conducted with trivalent chromium and steelhead trout (Salmo gairdneri). A 96-h LC50 of 4,400 micrograms/l chromium was obtained with two-month-old juvenile fish. Early life stage exposure from newly fertilized eggs to 30-d post-swim...

143

The Toxicity of Diquat, Endothall, and Fluridone to the Early Life Stages of Fish  

Microsoft Academic Search

While most aquatic herbicides have undergone some toxicity testing for effects on non-target aquatic organisms, little of this testing has been conducted on early life stages of gamefish found in lakes undergoing treatment. Commercial formulations of diquat, endothall, and fluridone were selected for acute toxicity testing using very early life stages of walleye (Stizostedion vitreum), largemouth bass (Micropterus salmoides), and

Eric A. Paul; Howard A. Simonin; John Symula; Robert W. Bauer

1994-01-01

144

A Four-Stage Method for Developing Early Interventions for Alcohol among Aboriginal Adolescents  

ERIC Educational Resources Information Center

This paper details a four-stage methodology for developing early alcohol interventions for at-risk Aboriginal youth. Stage 1 was an integrative approach to Aboriginal education that upholds Aboriginal traditional wisdom supporting respectful relationships to the Creator, to the land and to each other. Stage 2 used quantitative methods to…

Mushquash, Christopher J.; Comeau, M. Nancy; McLeod, Brian D.; Stewart, Sherry H.

2010-01-01

145

Stand structure and successional trends in virgin boreal forest reserves in Sweden  

Microsoft Academic Search

Fire history and stand structure was examined in twelve virgin forest stands situated within forest reserves in northern Sweden. The selected stands represented fire refuges as well as different successional stages after fire. Six of the stands were dominated by Norway spruce (Picea abies L. Karst.), three were dominated by Scots pine (Pinus sylvestris L.), and three were dominated by

Per Linder; Björn Elfving; Olle Zackrisson

1997-01-01

146

Rate of Belowground Carbon Allocation Differs with Successional Habit of Two Afromontane Trees  

PubMed Central

Background Anthropogenic disturbance of old-growth tropical forests increases the abundance of early successional tree species at the cost of late successional ones. Quantifying differences in terms of carbon allocation and the proportion of recently fixed carbon in soil CO2 efflux is crucial for addressing the carbon footprint of creeping degradation. Methodology We compared the carbon allocation pattern of the late successional gymnosperm Podocarpus falcatus (Thunb.) Mirb. and the early successional (gap filling) angiosperm Croton macrostachyus Hochst. es Del. in an Ethiopian Afromontane forest by whole tree 13CO2 pulse labeling. Over a one-year period we monitored the temporal resolution of the label in the foliage, the phloem sap, the arbuscular mycorrhiza, and in soil-derived CO2. Further, we quantified the overall losses of assimilated 13C with soil CO2 efflux. Principal Findings 13C in leaves of C. macrostachyus declined more rapidly with a larger size of a fast pool (64% vs. 50% of the assimilated carbon), having a shorter mean residence time (14 h vs. 55 h) as in leaves of P. falcatus. Phloem sap velocity was about 4 times higher for C. macrostachyus. Likewise, the label appeared earlier in the arbuscular mycorrhiza of C. macrostachyus and in the soil CO2 efflux as in case of P. falcatus (24 h vs. 72 h). Within one year soil CO2 efflux amounted to a loss of 32% of assimilated carbon for the gap filling tree and to 15% for the late successional one. Conclusions Our results showed clear differences in carbon allocation patterns between tree species, although we caution that this experiment was unreplicated. A shift in tree species composition of tropical montane forests (e.g., by degradation) accelerates carbon allocation belowground and increases respiratory carbon losses by the autotrophic community. If ongoing disturbance keeps early successional species in dominance, the larger allocation to fast cycling compartments may deplete soil organic carbon in the long run. PMID:23049813

Shibistova, Olga; Yohannes, Yonas; Boy, Jens; Richter, Andreas; Wild, Birgit; Watzka, Margarethe; Guggenberger, Georg

2012-01-01

147

Setting the Stage for Lifetime Physical Activity in Early Childhood  

ERIC Educational Resources Information Center

The purpose of this article is to provide a rationale and suggestions for emphasizing health-related physical education in preschool settings. In order to accomplish this, it will examine what is currently known about early childhood physical activity, as well as the existing professional preparation and accreditation standards for early childhood…

Schneider, Holly; Lounsbery, Monica

2008-01-01

148

Isolation of erythrocytes infected with viable early stages of Plasmodium falciparum by flow cytometry.  

PubMed

The erythrocytic life cycle of Plasmodium falciparum is highly associated with severe clinical symptoms of malaria that causes hundreds of thousands of death each year. The parasite develops within human erythrocytes leading to the disruption of the infected red blood cell (iRBC) prior to the start of a new cycle of erythrocyte infection. Emerging mechanisms of resistance against antimalarial drugs require improved knowledge about parasite's blood stages to facilitate new alternative antimalarial strategies. For the analysis of young blood stages of Plasmodium at the molecular level, the isolation of ring stages is essential. However, early stages can hardly be separated from both, late stages and non-infected red blood cells using conventional methods. Here, iRBCs were stained with the DNA-binding dyes Vybrant® DyeCycle™ Violet and SYBR® Green I. Subsequently, cells were subjected to flow-cytometric analysis. This enabled the discrimination of early stage iRBCs as well as late-stage iRBCs from non-infected erythrocytes and the properties of the used dyes were evaluated. Moreover, early stage iRBCs were isolated with high purity (>98%) by FACS. Subsequently, development of sorted early stages of the parasite was monitored over time and compared with control cultures. The described flow cytometry method, based on staining with Vybrant DyeCycle Violet, allows the isolation of viable ring stages of the malarial agent P. falciparum, and thereby provides the basis for new, broad-range molecular investigations of the parasite. PMID:23136095

Philipp, Stephan; Oberg, Hans-Heinrich; Janssen, Ottmar; Leippe, Matthias; Gelhaus, Christoph

2012-12-01

149

Radiotherapy Alone for Early-Stage Squamous Cell Carcinoma of the Larynx and Hypopharynx  

SciTech Connect

Purpose: To describe and illustrate examples of early-stage larynx and hypopharynx cancer that can be successfully treated with radiotherapy alone. Methods and Materials: Review of the NCCN and ASCO practice guidelines. Representative examples are included. Results: Early-stage larynx and hypopharynx cancer is defined by tumor extent based on physical and imaging examination. Conclusions: Radiotherapy alone is appropriate treatment for properly selected early-stage squamous cell carcinoma of the larynx and hypopharynx. The NCCN and ASCO practice guidelines can be an aid to the clinician in identifying favorable cancers that can be successfully treated with radiotherapy alone with preservation of organ function.

Foote, Robert L. [Department of Radiation Oncology, Mayo Clinic College of Medicine, Rochester, MN (United States)], E-mail: foote.robert@mayo.edu

2007-10-01

150

Using Motivational Interviewing within the Early Stages of Group Development  

ERIC Educational Resources Information Center

This article presents developmentally appropriate applications of Motivational Interviewing (MI; Miller & Rollnick, 2002) for use in preparing group members for the working stages of group. Practical strategies are offered for using MI to facilitate an atmosphere of trust, recognize member readiness for change, identify and resolve members'…

Young, Tabitha L.

2013-01-01

151

Medicines for Early Stage Chronic Kidney Disease: A Review of the Research for Adults with Kidney Disease and Diabetes ....  

MedlinePLUS

... Consumer Summary – Oct. 11, 2012 Medicines for Early Stage Chronic Kidney Disease: A Review of the Research ... a sign of kidney damage. What is early stage CKD? Your doctor may tell you that you ...

152

ERP Evidence of Visualization at Early Stages of Visual Processing  

ERIC Educational Resources Information Center

Recent neuroimaging research suggests that early visual processing circuits are activated similarly during visualization and perception but have not demonstrated that the cortical activity is similar in character. We found functional equivalency in cortical activity by recording evoked potentials while color and luminance patterns were viewed and…

Page, Jonathan W.; Duhamel, Paul; Crognale, Michael A.

2011-01-01

153

Ultrahigh resolution optical coherence tomography for the detection of early stage neoplastic pathologies  

E-print Network

Identification of changes associated with early stage disease remains a critical objective of clinical detection and treatment. Effective screening and detection is important for improving outcome because advanced disease, ...

Hsiung, Pei-Lin, 1975-

2005-01-01

154

76 FR 76907 - Small Business Investment Companies-Early Stage SBICs  

Federal Register 2010, 2011, 2012, 2013

...SMALL BUSINESS ADMINISTRATION 13 CFR...The Regulatory Impact Analysis is set forth below...Regulation The Small Business Investment Act of 1958...the Regulatory Impact Analysis under Executive Order...to early stage small businesses through the SBIC...

2011-12-09

155

RESPONSES OF EARLY LIFE HISTORY STAGES OF THE STRIPED BASS, 'MORONE SAXATILIS' TO CHLORINATION  

EPA Science Inventory

The toxicity of total residual chlorination (TRC) to early life stages of the striped bass, Morone saxatilis, was determined using percent embryo hatchability, incipient LC50 bioassays, histopathology, and avoidance responses. Beginning 8 to 9 hours after fertilization, developin...

156

Improvements to building energy usage modeling during early design stages and retrofits  

E-print Network

A variety of improvements to the MIT Design Advisor, a whole-building energy usage modeling tool intended for use during early design stages, are investigated. These include changes to the thermal mass temperature distribution ...

Mandelbaum, Andrew (Andrew Joseph)

2014-01-01

157

Personalized Unicompartmental Knee Implant Treats Early Stage Arthritis While Preserving Bone  

MedlinePLUS Videos and Cool Tools

Personalized Unicompartmental Knee Implant Treats Early Stage Arthritis while Preserving Bone (6:00pm CST) You must have Javascript enabled in your web browser. View Program Transcript Click Here to ...

158

The influence of immersion and presence in early stage engineering designing and building  

E-print Network

This paper explores the role of a designer's sense of engagement in early stage design. In the field of virtual reality, presence and immersion are standard measures of an individual's sense of engagement and involvement ...

Faas, Daniela

159

Growth Stages 2: Middle Childhood and Early Adolescence  

NSDL National Science Digital Library

This Science NetLinks lesson is the second of a two-part series aimed at introducing students to the different stages of growth and development in human beings from birth to 18 years of age. In this lesson, student interactives are used to help students focus on the kinds of physical changes that children of their age range begin to undergo during puberty.

Science Netlinks

2003-03-29

160

CMB quadrupole suppression. II. The early fast roll stage  

SciTech Connect

Within the effective field theory of inflation, an initialization of the classical dynamics of the inflaton with approximate equipartition between the kinetic and potential energy of the inflaton leads to a brief fast roll stage that precedes the slow roll regime. The fast roll stage leads to an attractive potential in the wave equations for the mode functions of curvature and tensor perturbations. The evolution of the inflationary perturbations is equivalent to the scattering by this potential and a useful dictionary between the scattering data and observables is established. Implementing methods from scattering theory we prove that this attractive potential leads to a suppression of the quadrupole moment for CMB and B-mode angular power spectra. The scale of the potential is determined by the Hubble parameter during slow roll. Within the effective field theory of inflation at the grand unification (GUT) energy scale we find that if inflation lasts a total number of e-folds N{sub tot}{approx}59, there is a 10%-20% suppression of the CMB quadrupole and about 2%-4% suppression of the tensor quadrupole. The suppression of higher multipoles is smaller, falling off as 1/l{sup 2}. The suppression is much smaller for N{sub tot}>59, therefore if the observable suppression originates in the fast roll stage, there is the upper bound N{sub tot}{approx}59.

Boyanovsky, D.; Vega, H. J. de [Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260 (United States); Observatoire de Paris, LERMA, Laboratoire Associe au CNRS UMR 8112, 61, Avenue de l'Observatoire, 75014 Paris (France); LPTHE, Universite Pierre et Marie Curie (Paris VI) et Denis Diderot (Paris VII), Laboratoire Associe au CNRS UMR 7589, Tour 24, 5eme. etage, 4, Place Jussieu, 75252 Paris, Cedex 05 (France); Sanchez, N. G. [Observatoire de Paris, LERMA, Laboratoire Associe au CNRS UMR 8112, 61, Avenue de l'Observatoire, 75014 Paris (France)

2006-12-15

161

Can some patients avoid adjuvant chemotherapy for early-stage breast cancer?  

Microsoft Academic Search

Adjuvant chemotherapy reduces the risk of relapse and mortality for women with early-stage breast cancer. However, many women diagnosed with early-stage breast cancer experience the toxic effects associated with adjuvant chemotherapy without any meaningful benefit. There are a variety of clinicopathological factors—including hormone receptor expression, histology, and proliferation markers such as Ki-67—that can be used to try to identify patients

Fatima Cardoso; Philippe L. Bedard

2011-01-01

162

Emotional expression and psychological and physical well-being among early-stage breast cancer patients  

Microsoft Academic Search

This study examined the relationships between emotional expression processes and physical and psychological well-being among early-stage breast cancer patients. Participants were 128 women (average age = 50.09, average years of education = 15.17) diagnosed with early stage breast cancer. Participants completed assessments by mail 4--8 weeks after their surgery and at 3, 6, and 12 month follow-up. Following the initial

Jenifer L. Culver

2002-01-01

163

Financing early-stage ventures: the role of uncertainty and financial markets in the investment choices of venture  

E-print Network

1 Financing early-stage ventures: the role of uncertainty and financial markets in the investment or her portfolio from later to early-stage investment. We explain why, during certain periods, there is a strong correlation between the performance of financial markets and the funds invested in early-stage

Paris-Sud XI, Université de

164

Developmental rate and behavior of early life stages of bighead carp and silver carp  

USGS Publications Warehouse

The early life stages of Asian carp are well described by Yi and others (1988), but since these descriptions are represented by line drawings based only on live individuals and lacked temperature controls, further information on developmental time and stages is of use to expand understanding of early life stages of these species. Bighead carp and silver carp were cultured under two different temperature treatments to the one-chamber gas bladder stage, and a photographic guide is provided for bighead carp and silver carp embryonic and larval development, including notes about egg morphology and larval swimming behavior. Preliminary information on developmental time and hourly thermal units for each stage is also provided. Both carp species developed faster under warmer conditions. Developmental stages and behaviors are generally consistent with earlier works with the exception that strong vertical swimming immediately after hatching was documented in this report.

Chapman, Duane C.; George, Amy E.

2011-01-01

165

Comparative toxicity of inorganic contaminants released by placer mining to early life stages of salmonids  

Microsoft Academic Search

The acute toxicities of four trace inorganics associated with placer mining were determined, individually and in environmentally relevant mixtures, to early life stages of Arctic grayling (Thymallus arcticus) from Alaska and Montana, coho salmon (Oncorhynchus kisutch) from Alaska and Washington, and rainbow trout (Oncorhynchus mykiss) from Montana. The descending rank order of toxicity to all species and life stages was

K. J. Buhl; S. J. Hamilton

1990-01-01

166

Transcriptional Signature following Inhibition of Early-Stage Cell Wall Biosynthesis in Staphylococcus aureus?  

PubMed Central

To facilitate mode of action studies on antibacterial inhibitors of early-stage cell wall biosynthesis (CWB), we determined the transcriptional response of Staphylococcus aureus to depletion/inhibition of enzymes in this pathway by DNA microarray analysis. We identified a transcriptional signature distinct from that previously observed following exposure to inhibitors of late-stage CWB. PMID:19164146

O'Neill, A. J.; Lindsay, J. A.; Gould, K.; Hinds, J.; Chopra, I.

2009-01-01

167

The Serum Glycome to Discriminate between Early-Stage Epithelial Ovarian Cancer and Benign Ovarian Diseases  

PubMed Central

Epithelial ovarian cancer (EOC) is the sixth most common cause of cancer deaths in women because the diagnosis occurs mostly when the disease is in its late-stage. Current diagnostic methods of EOC show only a moderate sensitivity, especially at an early-stage of the disease; hence, novel biomarkers are needed to improve the diagnosis. We recently reported that serum glycome modifications observed in late-stage EOC patients by MALDI-TOF-MS could be combined as a glycan score named GLYCOV that was calculated from the relative areas of the 11 N-glycan structures that were significantly modulated. Here, we evaluated the ability of GLYCOV to recognize early-stage EOC in a cohort of 73 individuals comprised of 20 early-stage primary serous EOC, 20 benign ovarian diseases (BOD), and 33 age-matched healthy controls. GLYCOV was able to recognize stage I EOC whereas CA125 values were statistically significant only for stage II EOC patients. In addition, GLYCOV was more sensitive and specific compared to CA125 in distinguishing early-stage EOC from BOD patients, which is of high relevance to clinicians as it is difficult for them to diagnose malignancy prior to operation. PMID:25183900

Braicu, Elena Iona; Sehouli, Jalid; Tauber, Rudolf; Blanchard, Véronique

2014-01-01

168

TOXICITY OF AMMONIA TO EARLY LIFE STAGES OF THE GREEN SUNFISH (LEPOMIS CYANELLUS)  

EPA Science Inventory

Toxicity of ammonia to early life stages of green sunfish Lepomis cyanellus was studied. One chronic and four acute exposure studies were conducted. During the chronic study green sunfish were exposed to a series of ammonia concentrations from the blastula stage through 40 days p...

169

Familiarity and Emotional Expression Influence an Early Stage of Face Processing: An Electrophysiological Study  

ERIC Educational Resources Information Center

Recent data indicate that the familiarity and the emotional expression of faces occur at an early stage of information processing. The goal of the present study was to determine whether these two aspects interact at the structural encoding stage as reflected by the N170 component of event-related potentials in tasks requiring the subjects either…

Caharel, Stephanie; Courtay, Nolwenn; Bernard, Christian; Lalonde, Robert; Rebai, Mohamed

2005-01-01

170

Detecting Very Early Stages of Dementia from Normal Aging with Machine Learning Methods  

E-print Network

Detecting Very Early Stages of Dementia from Normal Aging with Machine Learning Methods William to learn the best decision rules to distinguish normal brain aging from the earliest stages of dementia using subsamples of 198 normal and 244 cognitively impaired or very mildly demented (Clinical Dementia

Pazzani, Michael J.

171

Detecting Very Early Stages of Dementia from Normal Aging with Machine Learning Methods  

E-print Network

Detecting Very Early Stages of Dementia from Normal Aging with Machine Learning Methods William decision rules to distinguish normal brain aging from the earliest stages of dementia using subsamples of 198 normal and 244 cognitively impaired or very mildly demented (Clinical Dementia Rating Scale=0

Pazzani, Michael J.

172

An Analytical Theory for the Early Stage of the Development of Hurricanes: Part II  

Microsoft Academic Search

In this series of papers, an analytical theory for the early stage (tropical storm stage) of hurricane development is proposed. In Part I, a linear theory and a nonlinear theory have been formulated. It was found in Part I that the linear theory, a kind of the 2D Rankine vortex, gives some unrealistic properties for hurricane development at the upper

Chanh Q. Kieu

2004-01-01

173

The circadian clock starts ticking at a developmentally early stage.  

PubMed

Although overt diurnal rhythms of behavior do not begin until well after birth, molecular studies suggest that the circadian clock may begin much earlier at a cellular level: mouse embryonic fibroblasts, for example, already possess robust clocks. By multiple criteria, we found no circadian clock present in mouse embryonic stem cells. Nevertheless, upon their differentiation into neurons, circadian gene expression was observed. In the first steps along the pathway from ES cells to neurons, a neural precursor cell (NPC) line already showed robust circadian oscillations. Therefore, at a cellular level, the circadian clock likely begins at the very earliest stages of mammalian development. PMID:21135160

Kowalska, Elzbieta; Moriggi, Ermanno; Bauer, Christoph; Dibner, Charna; Brown, Steven A

2010-12-01

174

Features controlling the early stages of creep deformation of Waspaloy  

NASA Technical Reports Server (NTRS)

A model has been presented for describing primary and second stage creep. General equations were derived for the amount and time of primary creep. It was shown how the model can be used to extrapolate creep data. Applicability of the model was demonstrated for Waspaloy with gamma prime particle sizes from 75 - 1000 A creep tested in the temperature range 1000 - 1400 F (538 - 760 C). Equations were developed showing the dependence of creep parameters on dislocation mechanism, gamma prime volume fraction and size.

Ferrari, A.; Wilson, D. J.

1974-01-01

175

Screening of early antigen genes of adult-stage Trichinella spiralis using pig serum from different stages of early infection  

Technology Transfer Automated Retrieval System (TEKTRAN)

The goal of this work was to identify novel, early antigens present in Trichinella spiralis. To this end, a cDNA library generated from 3-day old adult worms (Ad3) was immunologically screened using serum from a pig infected with 20,000 muscle larvae. The serum was obtained from multiple, time cours...

176

Embryo-uterine interactions during early stages of pregnancy in domestic mammals  

E-print Network

Embryo-uterine interactions during early stages of pregnancy in domestic mammals M. GUILLOMOT during early pregnancy in domestic mammals ; the second part gives results of in vitro biochemical mammals (pig, rabbit) but not in all of them. Although local modifications of uterine protein synthesis

Paris-Sud XI, Université de

177

Cardiovascular remodelling and extracellular fluid excess in early stages of chronic kidney disease  

Microsoft Academic Search

Backgound. Patients with a mild to moderate decrease of glomerular filtration rate (GFR) are at risk of cardiovascular (CV) events and CV remodelling has been demonstrated in patients with advanced chronic kidney disease (CKD). However, early stages of CKD and the mechanisms involved in these modifications have not been studied. Methods. A total of 104 patients with early CKD (mean

Marie Essig; Brigitte Escoubet; Dominique de Zuttere; Francoise Blanchet; Florence Arnoult; Emmanuel Dupuis; Catherine Michel; Francoise Mignon; Christine Clerici; Francois Vrtovsnik

2008-01-01

178

Investigation of Turbulence in the Early Stages of a High Resolution Supernova Simulation  

E-print Network

Investigation of Turbulence in the Early Stages of a High Resolution Supernova Simulation Robert curves of Type Ia supernovae (SN Ia) as tools for surveying vast distances. Previous simulations have. In this video, we show the turbulence within the early "bubble" of a supernova via renderings of the magnitude

Bell, John B.

179

Multiple Adaptive Mechanisms to Chronic Liver Disease Revealed at Early Stages of Liver Carcinogenesis  

E-print Network

Multiple Adaptive Mechanisms to Chronic Liver Disease Revealed at Early Stages of Liver-knockout (Mdr2-KO) mice. These mice lack the liver-specific P-glycoprotein responsible by hepatocellular carcinoma development after the age of 1 year. Liver tissue samples of Mdr2-KO mice in the early

Domany, Eytan

180

Intermodal auditory, visual, and tactile attention modulates early stages of neural processing  

E-print Network

Intermodal auditory, visual, and tactile attention modulates early stages of neural processing-related potentials (ERPs) and gamma band oscillatory responses (GBRs) to examine whether intermodal attention operates early in the auditory, visual, and tactile modalities. To control for the effects of spatial

Knight, Robert T.

181

Formal Verification Toolkit for Requirements and Early Design Stages  

NASA Technical Reports Server (NTRS)

Efficient flight software development from natural language requirements needs an effective way to test designs earlier in the software design cycle. A method to automatically derive logical safety constraints and the design state space from natural language requirements is described. The constraints can then be checked using a logical consistency checker and also be used in a symbolic model checker to verify the early design of the system. This method was used to verify a hybrid control design for the suit ports on NASA Johnson Space Center's Space Exploration Vehicle against safety requirements.

Badger, Julia M.; Miller, Sheena Judson

2011-01-01

182

Early diagnosis and stage-adapted treatment of Wegener's granulomatosis.  

PubMed

A case of Wegener's granulomatosis (WG) presenting with hearing loss and right facial nerve palsy is reported. The definitive diagnosis was based upon clinical data and serum cANCA and AECA detection. Early assessment of WG prevented surgical facial nerve decompression to treat a chronic otitis media complication. Immunosuppressive therapy with steroids, cyclophosphamide and methotrexate was required for relief of clinical symptoms and cANCA negativity as an expression of disease remission. The effectiveness of co-trimoxazole for preventing relapses of WG is discussed. PMID:12648379

Cadoni, G; Agostino, S; Campobasso, E; Vulpiani, P; Manna, R; Galli, J

2003-03-01

183

Building on the Early Years Foundation Stage: Developing Good Practice for Transition into Key Stage 1  

ERIC Educational Resources Information Center

The Independent Review of the Primary Curriculum and the independent Cambridge Primary Review both highlight the need to re-think children's educational experiences in English classrooms between the ages of five and seven. Recent government initiatives have led to experiences in these early primary years being adult-directed and often in…

Fisher, Julie

2011-01-01

184

Methods for Surgical Targeting of the STN in Early-Stage Parkinson's Disease.  

PubMed

Patients with Parkinson's disease (PD) experience progressive neurological decline, and future interventional therapies are thought to show most promise in early stages of the disease. There is much interest in therapies that target the subthalamic nucleus (STN) with surgical access. While locating STN in advanced disease patients (Hoehn-Yahr Stage III or IV) is well understood and routinely performed at many centers in the context of deep brain stimulation surgery, the ability to identify this nucleus in early-stage patients has not previously been explored in a sizeable cohort. We report surgical methods used to target the STN in 15 patients with early PD (Hoehn-Yahr Stage II), using a combination of image guided surgery, microelectrode recordings, and clinical responses to macrostimulation of the region surrounding the STN. Measures of electrophysiology (firing rates and root mean squared activity) have previously been found to be lower than in later-stage patients, however, the patterns of electrophysiology seen and dopamimetic macrostimulation effects are qualitatively similar to those seen in advanced stages. Our experience with surgical implantation of Parkinson's patients with minimal motor symptoms suggest that it remains possible to accurately target the STN in early-stage PD using traditional methods. PMID:24678307

Camalier, Corrie R; Konrad, Peter E; Gill, Chandler E; Kao, Chris; Remple, Michael R; Nasr, Hana M; Davis, Thomas L; Hedera, Peter; Phibbs, Fenna T; Molinari, Anna L; Neimat, Joseph S; Charles, David

2014-01-01

185

Methods for Surgical Targeting of the STN in Early-Stage Parkinson’s Disease  

PubMed Central

Patients with Parkinson’s disease (PD) experience progressive neurological decline, and future interventional therapies are thought to show most promise in early stages of the disease. There is much interest in therapies that target the subthalamic nucleus (STN) with surgical access. While locating STN in advanced disease patients (Hoehn–Yahr Stage III or IV) is well understood and routinely performed at many centers in the context of deep brain stimulation surgery, the ability to identify this nucleus in early-stage patients has not previously been explored in a sizeable cohort. We report surgical methods used to target the STN in 15 patients with early PD (Hoehn–Yahr Stage II), using a combination of image guided surgery, microelectrode recordings, and clinical responses to macrostimulation of the region surrounding the STN. Measures of electrophysiology (firing rates and root mean squared activity) have previously been found to be lower than in later-stage patients, however, the patterns of electrophysiology seen and dopamimetic macrostimulation effects are qualitatively similar to those seen in advanced stages. Our experience with surgical implantation of Parkinson’s patients with minimal motor symptoms suggest that it remains possible to accurately target the STN in early-stage PD using traditional methods. PMID:24678307

Camalier, Corrie R.; Konrad, Peter E.; Gill, Chandler E.; Kao, Chris; Remple, Michael R.; Nasr, Hana M.; Davis, Thomas L.; Hedera, Peter; Phibbs, Fenna T.; Molinari, Anna L.; Neimat, Joseph S.; Charles, David

2013-01-01

186

The fourfold Democritus on the stage of early modern science.  

PubMed

The renewed success of ancient atomism in the seventeenth century has baffled historians not only because of the lack of empirical evidence in its favor but also because of the exotic heterogeneity of the models that were proposed under its name. This essay argues that one of the more intriguing reasons for the motley appearance of early modern atomism is that Democritus, with whose name this doctrine was most commonly associated, was a figure of similar incoherence. There existed in fact no fewer than four quite different Democriti of Abdera and as many literary traditions: the atomist, the "laughing philosopher," the moralizing anatomist, and the alchemist. Around the year 1600 the doctrines of these literary figures, three of whom had no tangible connection with atomism, began to merge into further hybrid personae, some of whom possessed notable scientific potential. This essay offers the story of how these Democriti contributed to the rise of incompatible "atomisms." PMID:11143784

Lüthy, C

2000-09-01

187

Cost analysis of adjuvant management strategies in early stage (stage I) testicular seminoma  

PubMed Central

Background Acceptable post-orchiectomy adjuvant therapy strategies for stage I seminoma patients include surveillance, para-aortic radiation therapy (RT), dog-leg RT, and a single cycle of carboplatin. The required follow-up recommendations were amended by the National Comprehensive Cancer Network (NCCN) in 2012. Given a cause-specific survival of nearly 100%, a closer analysis of the reimbursement for each treatment strategy is warranted. Methods NCCN guidelines were used to design treatment plans for each acceptable adjuvant treatment strategy. Follow-up charges were generated for 10 years based on 2012 (version 1.2012; unchanged in current version 1.2013) and 2011 NCCN (version 2.2011) surveillance recommendations. The 2012 Medicare reimbursement rates were used to calculate each treatment strategy and incremental cost-effectiveness ratios to compare the treatment options. Results Under the current NCCN follow-up recommendations, the total reimbursements generated over 10 years of surveillance, para-aortic RT, dog-leg RT, and carboplatin were $10,643, $11,678, $9,662, and $10,405, respectively. This is compared with the reimbursements as per the 2011 NCCN recommendations: $20,986, $11,517, $9,394, and $20,365 respectively. Factoring the rates of relapse into a salvage model, observation was found to be more costly and less effective ($–1,831, $?7,318, $–7,010) in the adjuvant management of stage I seminoma patients Conclusion Based on incremental cost-effectiveness ratios, para-aortic RT, dog-leg RT, and carboplatin are cost-effective options for the treatment of stage I seminoma when compared with observation; however, surveillance could potentially spare as many as 80%–85% of men diagnosed with stage I seminoma from additional therapy after radical inguinal orchiectomy. Such cost and reimbursement analyses are becoming increasingly relevant, but are not meant to usurp sound clinical judgment. Further studies are required to validate these findings. PMID:25610815

Cox, John A; Gajjar, Shefali R; Lanni, Thomas B; Swanson, Todd A

2015-01-01

188

Alternatives to the fish early life-stage test: Developing a conceptual model for early fish development  

EPA Science Inventory

Chronic fish toxicity is a key parameter for hazard classification and environmental risk assessment of chemicals, and the OECD 210 fish early life-stage (FELS) test is the primary guideline test used for various international regulatory programs. There exists a need to develop ...

189

Endogenous Opioids Inhibit Early Stage Pancreatic Pain in a Mouse Model of Pancreatic Cancer  

PubMed Central

Background & Aims The endogenous opioid system is involved in modulating the experience of pain, the response to stress and the action of analgesic therapies. Recent human imaging studies have demonstrated a significant tonic modulation of visceral pain, raising the question of whether endogenous opioids tonically modulate the pain of visceral cancer. Methods Transgenic mice expressing the first 127 amino acids of simian virus 40 large T antigen, under the control of the rat elastase-1 promoter that spontaneously develop pancreatic cancer were used to investigate the role of endogenous opioids in the modulation of pancreatic cancer pain. Visceral pain behaviors were assessed as degree of hunching and vocalization. Results Whereas, mice with late stage pancreatic cancer displayed spontaneous, morphine-reversible, visceral pain-related behaviors such as hunching and vocalization, these behaviors were absent in mice with early stage pancreatic cancer. Following systemic administration of the central nervous system (CNS) penetrant opioid receptor antagonists naloxone or naltrexone, mice with early stage pancreatic cancer, displayed significant visceral pain-related behaviors, while systemic administration of the CNS non-penetrant opioid antagonist naloxone-methiodide did not induce an increase in visceral pain behaviors. Conclusions Our findings suggest that a CNS opioid-dependent mechanism tonically modulates early and late stage pancreatic cancer pain. Understanding the mechanisms that mask this pain in early stage disease and drive this pain in late stage disease may allow improved diagnosis, treatment, and care of patients with pancreatic cancer. PMID:16952558

Sevcik, Molly A.; Jonas, Beth M.; Lindsay, Theodore H.; Halvorson, Kyle G.; Ghilardi, Joseph R.; Kuskowski, Michael A.; Mukherjee, Pinku; Maggio, John E.; Mantyh, Patrick W.

2007-01-01

190

Seismic anisotropy and texture development during early stages of subduction  

NASA Astrophysics Data System (ADS)

Shear wave splitting measurements are frequently used to infer upper mantle flow trajectory, based on the fact that, under strain, olivine develops lattice-preferred orientation (LPO) textures in the convecting mantle. However, such inferences ought to be made carefully, since the relationship between splitting fast polarisation and olivine LPO depends on several factors, one of them being the deformation history of the volume of mantle in question. This is especially the case in regions such as subduction zones, where complex and time-dependent mantle flow occurs. Here, we present an integrated model to simulate strain-history-dependent LPO development and measure the resulting shear wave splitting in a subduction setting. We do this for a subduction model that approximates the geometry of the double-sided Molucca Sea subduction system in eastern Indonesia. We test a single-sided and a double-sided subduction case, and compare the results to shear wave splitting observations of this region. Since the subduction zone is fairly young, early textures from the slab's descent from the near-surface to the bottom of the mantle transition zone - which we simulate in our models - have not yet been overprinted by subsequent continuous flow. It further allows us to test the significance of the double-sided geometry, i.e., the need for a rear barrier to achieve trench-parallel sub-slab mantle flow. We simulate olivine LPO evolution in polycrystalline aggregates as they move and deform along pathlines extracted from a 3-D mantle flow model. Interactions between crystals are described using the visco-plastic self-consistent (VPSC) approach. Unlike previous studies, we consider the entire subduction history from subduction initiation onwards. After calculating elastic properties associated with LPO textures, we estimate the resulting splitting parameters (fast direction ?, delay time ?t) for synthetic SKS phases. Our models demonstrate that complex, backazimuth-dependent behaviour in ? appears in even apparently simple models of subduction zone mantle flow. We also show that although a rear barrier amplifies trench-parallel sub-slab anisotropy due to mantle flow, it is not essential for producing trench-parallel fast directions. In a simple model of one-sided subduction and deformation dominated by the motion of dislocations belonging to the (010)[100] slip system, trench-parallel fast directions result from a combination of simple shear and deformation by axial compression in the sub-slab mantle.

Di Leo, Jeanette; Walker, Andrew; Li, Zhong-Hai; Wookey, James; Ribe, Neil; Kendall, J.-Michael; Tommasi, Andréa

2014-05-01

191

Gas exchange, leaf structure and nitrogen in contrasting successional tree species growing in open and understory sites during a drought.  

PubMed

Seasonal ecophysiology, leaf structure and nitrogen were measured in saplings of early (Populus grandidentata Michx. and Prunus serotina J.F. Ehrh.), middle (Fraxinus americana L. and Carya tomentosa Nutt.) and late (Acer rubrum L. and Cornus florida L.) successional tree species during severe drought on adjacent open and understory sites in central Pennsylvania, USA. Area-based net photosynthesis (A) and leaf conductance to water vapor diffusion (g(wv)) varied by site and species and were highest in open growing plants and early successional species at both the open and understory sites. In response to the period of maximum drought, both sunfleck and sun leaves of the early successional species exhibited smaller decreases in A than leaves of the other species. Shaded understory leaves of all species were more susceptible to drought than sun leaves and had negative midday A values during the middle and later growing season. Shaded understory leaves also displayed a reduced photosynthetic light response during the peak drought period. Sun leaves were thicker and had a greater mass per area (LMA) and nitrogen (N) content than shaded leaves, and early and middle successional species had higher N contents and concentrations than late successional species. In both sunfleck and sun leaves, seasonal A was positively related to predawn leaf Psi, g(wv), LMA and N, and was negatively related to vapor pressure deficit, midday leaf Psi and internal CO(2). Although a significant amount of plasticity occurred in all species for most gas exchange and leaf structural parameters, middle successional species exhibited the largest degree of phenotypic plasticity between open and understory plants. PMID:14965944

Abrams, M D; Mostoller, S A

1995-06-01

192

A profile of identity in early-stage dementia and a comparison with healthy older people.  

PubMed

The aim of the study was to determine whether people in the early stages of dementia experience their sense of identity differently to healthy older people and to examine whether different aspects of identity are related to each other in each group. This was a cross-sectional questionnaire-based study; 50 people with early-stage dementia and 50 age-matched people without dementia completed measures pertaining to different aspects of identity. Measures of mood and self-esteem were also included so that any differences could be taken into account in the analysis. There were very few differences in identity between the groups. After differences in levels of anxiety were accounted for, there were no differences in scores on most measures of identity. However, people in the early stages of dementia scored significantly lower on one subtotal for one measure of identity, whereas healthy older adults reported significantly more identity-related distress than people in the early stages of dementia. For both groups, there were no associations between different aspects of identity. People in the early stages of dementia do not differ much from healthy older adults in terms of their identity. Since healthy older people experience more distress relating to identity, they may be more likely to benefit from some sort of intervention than people in the early stages of dementia. It might be useful to consider identity as consisting of multiple components in future studies, rather than assuming that one aspect of identity represents the overall experience of identity. PMID:23171274

Caddell, Lisa S; Clare, Linda

2013-01-01

193

Effects of acidified seawater on early life stages of scleractinian corals (Genus Acropora )  

Microsoft Academic Search

Ocean acidification, caused by increased atmospheric carbon dioxide (CO2) concentrations, is currently an important environmental problem. It is therefore necessary to investigate the effects of\\u000a ocean acidification on all life stages of a wide range of marine organisms. However, few studies have examined the effects\\u000a of increased CO2 on early life stages of organisms, including corals. Using a range of

Ryota Suwa; Masako Nakamura; Masaya Morita; Kazuaki Shimada; Akira Iguchi; Kazuhiko Sakai; Atsushi Suzuki

2010-01-01

194

Outcomes in Patients With Early-Stage Hypopharyngeal Cancer Treated With Radiotherapy  

SciTech Connect

Purpose: To analyze the outcome in patients with early-stage hypopharyngeal cancer (HPC) who were treated with radiotherapy (RT). Methods and Materials: Between February 1988 and February 2007, 77 patients with Stage I or Stage II HPC underwent definitive RT in the Division of Radiation Oncology at the National Cancer Center Hospital. Eleven of the patients received local irradiation, and the other 66 patients received elective bilateral neck irradiation and booster irradiation to the primary lesion. The median follow-up period for all the patients was 33 months from the start of RT, ranging from 3 to 229 months. Results: The rates of overall survival, HPC-specific survival, HPC recurrence-free survival, and local control with laryngeal voice preservation for the 77 patients at 5 years were 47%, 74%, 57%, and 70%, respectively. The survival rates were not affected by the patient characteristics or treatment factors, but the RT field was significantly correlated with local control in a multivariate analysis. Seven of the patients had Grade 3 or greater complications, but these complications occurred after salvage surgery in 6 of the patients. Of the 77 patients, 83% had synchronous or metachronous malignancies, but these malignancies did not influence the survival of the patients if the malignancies were detected at an early stage. Conclusion: RT is an appropriate treatment method for early-stage HPC. However, because synchronous or metachronous malignancies occur at a relatively high frequency, careful follow-up and the early detection of such malignancies are critical.

Yoshimura, Ryo-ichi, E-mail: ysmrmrad@tmd.ac.j [Division of Radiation Oncology, National Cancer Center Hospital, Tokyo (Japan); Department of Diagnostic Radiology and Oncology, Head and Neck Reconstruction Division, Graduate School, Tokyo Medical and Dental University, Tokyo (Japan); Kagami, Yoshikazu; Ito, Yoshinori [Division of Radiation Oncology, National Cancer Center Hospital, Tokyo (Japan); Asai, Masao [Division of Head and Neck Surgery, National Cancer Center Hospital, Tokyo (Japan); Mayahara, Hiroshi; Sumi, Minako; Itami, Jun [Division of Radiation Oncology, National Cancer Center Hospital, Tokyo (Japan)

2010-07-15

195

Stress-Diffusion Coupling and Viscoelastic Effects on Early Stage Spinodal Decomposition in Polymer Solutions  

NASA Astrophysics Data System (ADS)

We investigated the viscoelastic effects on the early stage spinodal decomposition (SD) in semidilute polymer solutions where the coupling of stress and diffusion plays an important role. The so-called viscoelastic length ?ve, within which the stress suppresses the growth of the concentration fluctuations, was quantitatively evaluated experimentally. The evaluated value was found out to become as large as 9.0×102 nm. The obtained value ?ve agrees well with that independently estimated from the diffusion and viscoelasticity measurements, indicating that the Doi-Onuki theory can well describe the viscoelastic effects on the dynamics of the early stage SD.

Takenaka, Mikihito; Toyoda, Nobuyuki; Saito, Shin; Hashimoto, Takeji

196

Percutaneous traction-assisted EMR by using an insulation-tipped electrosurgical knife for early stage gastric cancer  

Microsoft Academic Search

BackgroundEMR now is accepted as a minimally invasive treatment for early stage gastric cancer. However, the endoscopic approach sometimes is limited by the size and location of the tumor. The technique and early results of percutaneous, traction-assisted EMR for resection of larger early stage gastric cancers is described.

Hitoshi Kondo; Takuji Gotoda; Hiroyuki Ono; Ichiro Oda; Takahiro Kozu; Mitsuhiro Fujishiro; Daizo Saito; Shigeaki Yoshida

2004-01-01

197

Effects of cigarette smoke exposure on early stage embryos in the rat  

SciTech Connect

It is well recognized that cigarette smoking in pregnant women exerts many deleterious effects on their progenies; intrauterine growth retardation, and increases in perinatal mortality and premature births. The fetal growth retardation also has been reported in animals exposed to cigarette smoke. The authors previously demonstrated that cigarette smoke exposure in pregnant rats retarded the growth of fetuses from mid to late stages of pregnancy. In addition, the weight of uteri containing embryos in animals inhaling the smoke was smaller, although not significant, than that in the control on day 7 of pregnancy. Based on these findings, it was suggested that the growth of embryos in early stage seemed to be harmfully affected as well as during mid and late stages of pregnancy. However, since the uterine weight in early pregnancy was measured in the previous study instead of the direct observation of early stage embryos, it remained unclear whether the early development of embryos was really influenced by cigarette smoke exposure or not. The present study was designed to observe the effects of cigarette smoke inhalation by pregnant rats on early development of embryos from fertilization to implantation.

Tachi, Norihide; Aoyama, Mitsuko (Nagoya City Univ. Medical School (Japan))

1989-09-01

198

A simple novel prognostic model for early stage oral tongue cancer.  

PubMed

The prognostication of patient outcome is one of the greatest challenges in the management of early stage oral tongue squamous cell carcinoma (OTSCC). This study introduces a simple histopathological model for the prognostication of survival in patients with early OTSCC. A total of 311 cases (from Finland and Brazil) with clinically evaluated early stage OTSCC (cT1-T2cN0cM0) were included in this multicentre retrospective study. Tumour budding (B) and depth of invasion (D) were scored on haematoxylin-eosin-stained cancer slides. The cut-off point for tumour budding was set at 5 buds (low <5; high ?5) and for depth of invasion at 4mm (low <4mm; high ?4mm). The scores of B and D were combined into one model: the BD predictive model. On multivariate analysis, a high risk score (BD score 2) correlated significantly with loco-regional recurrence (P=0.033) and death due to OTSCC (P<0.001) in early stage OTSCC. The new BD model is a promising prognostic tool to identify those patients with aggressive cases of early stage OTSCC who might benefit from multimodality treatment. PMID:25457829

Almangush, A; Coletta, R D; Bello, I O; Bitu, C; Keski-Säntti, H; Mäkinen, L K; Kauppila, J H; Pukkila, M; Hagström, J; Laranne, J; Tommola, S; Soini, Y; Kosma, V-M; Koivunen, P; Kowalski, L P; Nieminen, P; Grénman, R; Leivo, I; Salo, T

2015-02-01

199

Management of early stage cutaneous Merkel cell carcinoma of the head and neck.  

PubMed

Merkel cell carcinoma (MCC) is a rare but aggressive skin cancer of neuroendocrine origin. As a result, few large studies have been published, and we know of even fewer on disease of the head and neck alone. The most appropriate way to manage patients with early local disease and no sign of metastases neck is controversial. We reviewed management of early cutaneous MCC of the head and neck in 8 hospitals in the United Kingdom over 12 years between 1999 and 2011 (the largest head and neck series in Europe to date), and identified 39 patients (19 men and 20 women) with early disease according to a well recognised classification. A total of 24 patients had stage Ia disease, 11 had stage Ib disease, and 4 were unclassified. Five of those with stage Ia disease developed regional metastases and 7 with stage Ib disease developed regional recurrence. The 2-year overall survival for stage Ia and Ib disease was 62% and 27%, respectively. Our study shows that prognosis is poor after conservative surgical management of stage I disease. Management of the neck is still controversial, and a meta-analysis of all the published data is needed to establish best practice statistically. PMID:25174318

Blythe, John N St J; Macpherson, David; Reuther, William J; Ethunandan, Madan; Ilankovan, Velupillai; Sharma, Sanjay; Anand, Rajiv A; Mellor, Timothy K; Kerawala, Cyrus; Brennan, Peter A

2014-11-01

200

Effects of temperature on survival and development of early life stage Pacific and western brook lampreys  

USGS Publications Warehouse

We examined the effects of temperature (10, 14, 18, and 22??C) on survival and development of Pacific lampreys Lampetra tridentata and western brook lampreys L. richardsoni during embryological and early larval stages. The temperature for zero development was estimated for each species, and the response to temperature was measured as the proportion of individuals surviving to hatch, surviving to the larval stage, and exhibiting abnormalities at the larval stage (i.e., malformations of the body). The estimated temperature for zero development was 4.850C for Pacific lampreys and 4.97??C for western brook lampreys. Survival was greatest at 18??C, followed by 14, 10, and 22??C, significant differences being observed between 22??C and the other temperatures. Overall survival was significantly greater for western brook lampreys than for Pacific lampreys; however, the overall difference in proportion of individuals surviving was only 0.02. Overall survival significantly decreased from the time of hatch (proportion surviving = 0.85) to the larval stage (0.82; i.e., during the free-embryo stage). The proportion of individuals exhibiting abnormalities at the larval stage was greatest at 22??C, followed by 18, 10, and 14??C, significant differences being observed between 22??C and the other temperatures. These data provide baseline information on the thermal requirements of early life stage Pacific and western brook lampreys and will aid in assessment and prediction of suitable spawning and rearing habitats for these species.

Meeuwig, M.H.; Bayer, J.M.; Seelye, J.G.

2005-01-01

201

Hydraulic compensation in northern Rocky Mountain conifers: does successional position and life history matter?  

PubMed

As trees grow tall and the resistance of the hydraulic pathway increases, water supply to foliage may decrease forcing stomata to close and CO2 uptake to decline. Several structural (e.g. biomass allocation) and physiological adjustments, however, may partially or fully compensate for such hydraulic constraints and prevent limitations on CO2 uptake and growth. The degree to which trees compensate for hydraulic constraints as they grow tall may depend on the costs and benefits associated with hydraulic compensation according to their ecology and life history. Because later successional Rocky Mountain conifers are more shade tolerant, optimization of CO2 uptake as trees grow tall and shade increases may confer greater benefits than in earlier successional species. If so, higher compensation for hydraulic constraints is expected in later successional species relative to co-occurring earlier successional species. I have examined height-related changes of crown stomatal conductance on a leaf area basis (G(LA)) and leaf to sapwood ratios (A(L):A(S)) for five conifer species in the northern Rocky Mountains. Species were arranged in pairs, each pair consisting of an early and late successional species. For high elevations I used, respectively, whitebark pine (Pinus albicaulis) and subalpine fir (Abies lasiocarpa); for mid-elevations, western larch (Larix occidentalis) and Douglas-fir (Pseudotsuga menziesii); for lower elevations, ponderosa pine (Pinus ponderosa) and Douglas-fir. A(L):A(S) either decreased (subalpine fir, ponderosa pine), remained constant (Douglas-fir, western larch) or increased (whitebark pine) with tree height. As hypothesized, earlier successional species (ponderosa pine, whitebark pine and western larch) exhibited significantly stronger decreases of G(LA) with tree height relative to their later successional pairs (Douglas-fir and subalpine fir), which fully compensated for height-related hydraulic constraints on G(LA). A life history approach that takes into account the optimization of size- and species-specific ecological functions may also help researchers better understand biomass allocation and hydraulic function in trees. PMID:16639568

Sala, Anna

2006-08-01

202

Sensitivity of early life stages of white sturgeon, rainbow trout, and fathead minnow to copper.  

PubMed

Populations of white sturgeon (WS; Acipenser transmontanus) are in decline in several parts of the United States and Canada, attributed primarily to poor recruitment caused by degradation of habitats, including pollution with contaminants such as metals. Little is known about sensitivity of WS to contaminants or metals such as copper (Cu). Here, acute (96 h) mortalities of WS early life stages due to exposure to Cu under laboratory conditions are reported. Two standard test species, rainbow trout (Oncorhynchus mykiss) and fathead minnow (Pimephales promelas), were exposed in parallel to determine relative sensitivity among species. Swim-up larvae [15 days post-hatch (dph)] and early juveniles (40-45 dph) of WS were more sensitive to Cu (LC(50) = 10 and 9-17 ?g/L, respectively) than were yolksac larvae (8 dph; LC(50) = 22 ?g/L) and the later juvenile life stage (100 dph; LC(50) = 54 ?g/L). WS were more sensitive to Cu than rainbow trout and fathead minnow at all comparable life stages tested. Yolksac larvae of rainbow trout and fathead minnow were 1.8 and 4.6 times, respectively, more tolerant than WS, while swim-up and juvenile life stages of rainbow trout were between 1.4- and 2.4-times more tolerant than WS. When plotted in a species sensitivity distribution with other fishes, the mean acute toxicity value for early life stage WS was ranked between the 1st and 2nd centile. The WS life stage of greatest Cu sensitivity coincides with the beginning of active feeding and close association with sediment, possibly increasing risk. WS early life stages are sensitive to aqueous copper exposure and site-specific water quality guidelines and criteria should be evaluated closely to ensure adequate protection. PMID:23124699

Vardy, David W; Oellers, Johanna; Doering, Jon A; Hollert, Henner; Giesy, John P; Hecker, Markus

2013-01-01

203

Linking forest structure and composition: avian diversity in successional forests of ChiloeIsland, Chile  

Microsoft Academic Search

We show how Chilean forest bird species richness, abundance and guild structure changes as a function of structural properties of forest stands. We surveyed bird assemblages in two old-growth (>200 years), two mid-successional (30-60 years), and two early-suc- cessional forest stands (4-20 years), from November 1999 to September 2000, on ChiloeIsland, southern Chile (42S). Birds were grouped into four habitat-use

Ivan A. Di; Juan J. Armesto; Sharon Reid; Kathryn E. Sieving; Mary F. Willson

204

Effect of ocean acidification on the early life stages of the blue mussel (Mytilus edulis)  

Microsoft Academic Search

Several experiments have shown a decrease of growth and calcification of organisms at decreased pH levels but relatively few studies have focused on early life stages which are believed to be more sensitive to environmental disturbances such as hypercapnia. Here, we present experimental data demonstrating that the growth of planktonic mussel (Mytilus edulis) larvae is significantly affected by a decrease

F. P. H. Gazeau; J.-P. Gattuso; C. Dawber; A. E. Pronker; F. Peene; J. Peene; C. H. R. Heip; J. J. Middelburg

2010-01-01

205

Adding Radiation to Chemotherapy May Improve Outcomes in Early-Stage Hodgkin Lymphoma  

Cancer.gov

Adding radiation therapy to chemotherapy may improve outcomes in patients with early-stage Hodgkin lymphoma, according to a paper published in the Cochrane Database of Systematic Reviews in February 2011, but the long-term effects of this regimen are not known.

206

AN EARLY STAGE IN THE PLANT RECOLONIZATION OF A NUCLEAR TARGET AREA  

Microsoft Academic Search

Vegetational analyses were conducted three years postdetonation in a ; nuclear target area in a Grayia spinosa-Lycium andersonii community in Yucca ; Fiat, Nevada. Annual plants dominated the early stage of recolonization and were ; quantitatively more abundant in the disturbed areas than in an adjacent ; undisturbed shrub community. Ment zelia albicaulis and Chaenactis steviodes ; occurred in both

W. H. Rickard; L. M. Shields

1963-01-01

207

The Power of Personality in Discriminating Between Healthy Aging and Early-Stage  

E-print Network

Inventory scores after education, age, scores on the Mini- Mental State Examination (MMSE; Folstein). In an attempt to increase sensitivity for early detection, vari- ous noncognitive risk factors for DAT have also in the preclinical stage of AD and have been linked to an increased risk of dementia (Berger, Fratiglioni, Forsell

208

Effects of Salinity on Early Life Stages of the Gulf Coast Toad, Incilius nebulifer (Anura: Bufonidae)  

E-print Network

Effects of Salinity on Early Life Stages of the Gulf Coast Toad, Incilius nebulifer (Anura a laboratory trial with Incilius nebulifer (synonym: Bufo nebulifer) to determine at what level salinity negatively affects hatching and metamorphosis, and how exposure to salinity during development affects

Lailvaux, Simon

209

Affiliated and Independent Venture Capitalists: Early Stages Screening and the Syndication / Leverage  

E-print Network

Affiliated and Independent Venture Capitalists: Early Stages Screening and the Syndication comparatively the interest and the advan- tages of the existence of heterogeneous institutions in the Venture Capital activity. We focus on the duality relevant in Europe between Independent Venture Capital- ists

Paris-Sud XI, Université de

210

A multiphase model for the early stages of the hydration of retarded oilwell cement  

E-print Network

A multiphase model for the early stages of the hydration of retarded oilwell cement J. Billingham, Birmingham B15 2TT, UK A.M. Harrisson The Rugby Group, RMC House Rugby CV21 2DT, UK Abstract. Cement is used in the oil industry to line oil wells. The major com- ponents of oilwell cement are tricalcium silicate (C3S

Billingham, John

211

Memory Club: A Group Intervention for People with Early-Stage Dementia and Their Care Partners  

ERIC Educational Resources Information Center

Purpose: Diagnosis of dementia in its early stages presents a window of opportunity for examining the immediate and long-term consequences of the illness at a point when the individual with memory loss can still participate in decision making. Design and Methods: Memory Club is a l0-session group program designed to provide information about…

Zarit, Steven H.; Femia, Elia E.; Watson, Jennifer; Rice-Oeschger, Laura; Kakos, Bernadette

2004-01-01

212

The potential for adjuvant therapy in early-stage cervical cancer  

Microsoft Academic Search

Summary Adjuvant therapy may potentially improve prognosis in women with early-stage cervical cancer who are at high risk of relapse after primary therapy. Patients with lymph node involvement at surgery are at high risk of recurrence and may benefit from adjuvant therapy, but many patients are treated with radical radiotherapy. At present there is no method of accurately identifying patients

E. J. Buxton; N. Saunders; G. R. P. Blackledge; K. Kelly; C. W. E. Redman; J. Monaghan; M. E. L. Paterson; D. M. Luesley

1990-01-01

213

Ab initio atomistic thermodynamics study of the early stages of Cu(100) oxidation  

E-print Network

. We predict the clean surface, the 0.25 monolayer oxygen-covered surface, and the missing-row re. In particular, oxidation of copper surfaces is of fundamental and practical importance. Copper, CuO, and Cu2O,8 The mechanisms manifested in the early stages of copper oxidation are not well un- derstood, especially under

McGaughey, Alan

214

Biogeochemical changes at early stage after the closure of radioactive waste geological repository in South Korea  

E-print Network

Biogeochemical changes at early stage after the closure of radioactive waste geological repository e Korea Radioactive Waste Agency (KORAD), 111, Daedeok-daero 989 beon-gil, Yuseong-gu, Daejeon 305 Organic waste a b s t r a c t Permanent disposal of low- and intermediate-level radioactive wastes

Ohta, Shigemi

215

Early-Stage Chunking of Finger Tapping Sequences by Persons Who Stutter and Fluent Speakers  

ERIC Educational Resources Information Center

This research note explored the hypothesis that chunking differences underlie the slow finger-tap sequencing performance reported in the literature for persons who stutter (PWS) relative to fluent speakers (PNS). Early-stage chunking was defined as an immediate and spontaneous tendency to organize a long sequence into pauses, for motor planning,…

Smits-Bandstra, Sarah; De Nil, Luc F.

2013-01-01

216

AdS/CFT for the early stages of heavy ion collisions  

E-print Network

I give a brief introduction to the AdS/CFT correspondence targeted at heavy-ion physicists. I also review some insights to our understanding of the early stages of heavy-ion collisions coming from selected studies made using methods of the AdS/CFT correspondence.

Romuald A. Janik

2014-09-26

217

Introduction At early stages of development, the embryo needs to establish  

E-print Network

3381 Introduction At early stages of development, the embryo needs to establish bilateral symmetry al., 1989; Harland and Gerhart, 1997; Zernicka-Goetz, 2002). By contrast, amniote embryos do not appear irreversibly to fix their polarity until much later, when gastrulation begins and the embryo may

Stern, Claudio

218

A Linear Chain Markov Model for Detection and Localization of Cells in Early Stage Embryo Development  

E-print Network

A Linear Chain Markov Model for Detection and Localization of Cells in Early Stage Embryo to find individual cell candidates within the em- bryo. These cell candidates are combined into embryo hy applications such as predicting blas- tocyst and can be used for assessing embryos in in vitro fertilization

Gould, Stephen

219

Early Stage Soliton Observations in the Sulu Sea* ZACHARY D. TESSLER AND ARNOLD L. GORDON  

E-print Network

Early Stage Soliton Observations in the Sulu Sea* ZACHARY D. TESSLER AND ARNOLD L. GORDON Lamont internal waves, identified as solitons, at three locations. Solitary internal waves have since been of the soliton generation site near Pearl Bank in the Sulu Archipelago. From here, waves propagate toward

Gordon, Arnold L.

220

Prolonged Exposure Therapy for a Vietnam Veteran with PTSD and Early-Stage Dementia  

ERIC Educational Resources Information Center

Although prolonged exposure therapy (PE) is considered an evidence-based treatment for PTSD, there has been little published about the use of this treatment for older adults with comorbid early-stage dementia. As the number of older adults in the United States continues to grow, so will their unique mental health needs. The present article…

Duax, Jeanne M.; Waldron-Perrine, Brigid; Rauch, Sheila A. M.; Adams, Kenneth M.

2013-01-01

221

Evaluation of hypothesized adverse outcome pathway linking thyroid peroxidase inhibition to fish early life stage toxicity  

EPA Science Inventory

There is an interest in developing alternatives to the fish early-life stage (FELS) test (OECD test guideline 210), for predicting adverse outcomes (e.g., impacts on growth and survival) using less resource-intensive methods. Development and characterization of adverse outcome pa...

222

EFFECTS OF FENVALERATE ON THE EARLY LIFE-STAGES OF TOPSMELT (ATHERINOPS AFFINIS)  

EPA Science Inventory

Flow-through acute and early life-stage (ELS) toxicity tests were conducted with topsmelt (Atherinops affinis), a Pacific Coast saltwater fish, and fenvalerate, a synthetic pyrethroid insecticide. he 96-h LC50 for juvenile fish was 0.66 ug/L. n the 30-d ELS test was laboratory-sp...

223

EFFECTS OF FENVALERATE ON THE EARLY LIFE STAGES OF TOPSMELT (ATHERINOPS AFFINIS)  

EPA Science Inventory

Flow-through acute and early life-stage (ELS) toxicity tests were conducted with topsmelt (Atherinops affinis), a Pacific Coast saltwater fish, and fenvalerate, a synthetic pyrethroid insecticide. he 96-h LC50 for juvenile fish was 0.66 ug?l. n the 30-d ELS test with laboratory-s...

224

GUIDELINES FOR CONDUCTING EARLY LIFE STAGE TOXICITY TESTS WITH JAPANESE MEDAKA (ORYZIAS LATIPES)  

EPA Science Inventory

This manual represents a procedural guide for conducting embryo-larval early life stage (ELS) toxicity tests with Japanese medaka (Oryzias latipes). hese procedures are based upon evaluation of published papers and recent methods development work conducted at our laboratory in Du...

225

"It's the Bread and Butter of Our Practice": Experiencing the Early Years Foundation Stage  

ERIC Educational Resources Information Center

This article presents the experiences of nursery and primary head teachers (n = 12) on the English Early Years Foundation Stage (EYFS) after its first year of implementation in 2010. Findings are drawn from a subset of data (head teachers of primary and nursery schools) which forms part of a larger Department for Children, Schools and Families…

Roberts-Holmes, Guy

2012-01-01

226

AMI: A University-Based Early Stage Technology Development and Commercialization Agent  

Microsoft Academic Search

This paper describes efforts to incorporate engineering students into early stage technology development and commercialization projects for industrial clients. In this model, students are mentored in a professional experience much like medical students are mentored in professional practice in teaching hospitals. This service is provided by the Advanced Manufacturing Institute at Kansas State University and is supported by grants from

Bradley A. Kramer; Jeff Tucker; Bret Lanz; Dale Wunderlich

227

Towards a Conceptualization of the Early Career Stage of Principalship: Current Research, Idiosyncrasies and Future Directions  

ERIC Educational Resources Information Center

This review aims at providing a synthesis of the scholarship that has sought to expand the understanding of the early career stage of principalship by documenting the experiences and tasks of new principals (NPs) in the first three years in the post, and their personal and organizational determinants. The synthesis is based on empirical research…

Oplatka, Izhar

2012-01-01

228

Propagating Uncertainty in Solar Panel Performance for Life Cycle Modeling in Early Stage Design  

E-print Network

models to reduce building time (Eisenhard et al. 2000). Ideally, the fidelity (accuracy) and buildingPropagating Uncertainty in Solar Panel Performance for Life Cycle Modeling in Early Stage Design One of the challenges in accurately applying metrics for life cycle assessment lies in accounting

Yang, Maria

229

MD Anderson researchers compare treatments, survival benefits for early-stage lung cancer  

Cancer.gov

Removal of the entire lobe of lung may offer patients with early-stage lung cancer better overall survival when compared with a partial resection, and stereotactic ablative radiotherapy (SABR) may offer the same survival benefit as a lobectomy for some patients, according to a study from The University of Texas MD Anderson Cancer Center.Click here to read the full press release.

230

Concurrent Data Elicitation Procedures, Processes, and the Early Stages of L2 Learning: A Critical Overview  

ERIC Educational Resources Information Center

Given the current methodological interest in eliciting direct data on the cognitive processes L2 learners employ as they interact with L2 data during the early stages of the learning process, this article takes a critical and comparative look at three concurrent data elicitation procedures currently employed in the SLA literature: Think aloud (TA)…

Leow, Ronald P.; Grey, Sarah; Marijuan, Silvia; Moorman, Colleen

2014-01-01

231

Early stages of gelation in gelatin solution detected by dynamic oscillating rheology and nuclear magnetic spectroscopy  

Microsoft Academic Search

This study focuses on the early stages of the gelation of an aqueous type A (pig skin) gelatin solution. The thermo-reversible mono and triple helix formation was observed by rheology and proton NMR relaxation measurements. At high temperatures (T>330K), gelatin molecules form flexible random coils of small hydrodynamic radius, the elastic modulus of the solution is relatively low. On decreasing

Mojgan Zandi; Hamid Mirzadeh; Christian Mayer

2007-01-01

232

Test Design Optimization in CAT Early Stage with the Nominal Response Model  

ERIC Educational Resources Information Center

The early stage of computerized adaptive testing (CAT) refers to the phase of the trait estimation during the administration of only a few items. This phase can be characterized by bias and instability of estimation. In this study, an item selection criterion is introduced in an attempt to lessen this instability: the D-optimality criterion. A…

Passos, Valeria Lima; Berger, Martijn P. F.; Tan, Frans E.

2007-01-01

233

Genetics of the early stages of invasion of the Lessepsian rabbitfish Siganus luridus  

Microsoft Academic Search

Information on the initial stages of dispersal and settlement are of great interest in understanding the dynamics of biological invasions and in designing management responses. A newly settled population of the Lessepsian rabbitfish migrant Siganus luridus, that arrived in Linosa Island (Sicily Strait) in 2000, offered a unique opportunity to examine the genetic variability of the early phase of invasion

Ernesto Azzurro; Daniel Golani; Giuseppe Bucciarelli; Giacomo Bernardi

2006-01-01

234

Genetics of the early stages of invasion of the Lessepsian rabbitfish Siganus luridus  

E-print Network

, 25 Siganus rivulatus, and one of Siganus (Lo) vulpinus and S. doliatus were used. Samples wereGenetics of the early stages of invasion of the Lessepsian rabbitfish Siganus luridus Ernesto population of the Lessepsian rabbitfish migrant Siganus luridus, that arrived in Linosa Island (Sicily Strait

Bernardi, Giacomo

235

Predation on Early Life Stages of Lake Sturgeon in the Peshtigo River, Wisconsin  

Microsoft Academic Search

Mortality of early life stages can limit recruitment of fishes, and understanding the impacts of various sources of mortality has long been a goal of fisheries management. The impacts of predation on lake sturgeon Acipenser fulvescens are not well understood. The objective of this study was to identify and quantify sources of predation that affect lake sturgeon eggs, larvae, and

David C. Caroffino; Trent M. Sutton; Robert F. Elliott; Michael C. Donofrio

2010-01-01

236

News Notes: Two Proteins May Be Key to Screening for Early-Stage Liver Cancer  

Cancer.gov

Researchers have identified an improved method of screening high-risk patients for one of the most common types of liver cancer, hepatocellular carcinoma (HCC), particularly if the patient has a history of hepatitis. By changing the threshold of one commonly used screening test and adding a second, complementary test, researchers were able to accurately identify more early stage HCC cases.

237

Prostatic Fatty Acids and Cancer Recurrence Following Radical Prostatectomy for Early-Stage Prostate Cancer  

Technology Transfer Automated Retrieval System (TEKTRAN)

Objective: Results from some observational studies suggest that diet and energy balance influence the clinical course of early-stage prostate cancer. To evaluate possible mechanisms, we prospectively examined the relation between prostatic concentrations of fatty acids at diagnosis and cancer recurr...

238

Body Weight Status, Inflammation, and Prognostic Markers in Early-Stage Prostate Cancer  

E-print Network

Body Weight Status, Inflammation, and Prognostic Markers in Early-Stage Prostate Cancer Brown Bag (UICCC) IHRP Fellow #12;Outline Relative risk of cancer mortality in obese men Pathophysiologic basis for excess risk The case for inflammation/immunity in prostate cancer Preliminary results from

Illinois at Chicago, University of

239

Reducing Treatment Intensity Doesn't Compromise Results in Early-Stage Hodgkin Lymphoma  

Cancer.gov

Reducing the dose of chemotherapy and radiotherapy did not compromise treatment efficacy in patients  with early-stage, low-risk Hodgkin lymphoma but led to fewer side effects, according to a study published August 12, 2010, in the New England Journal of Medicine.

240

EFFECTS OF COPPER ON EARLY LIFE HISTORY STAGES OF NORTHERN ANCHOVY, ENGRAULIS MORDAX  

E-print Network

EFFECTS OF COPPER ON EARLY LIFE HISTORY STAGES OF NORTHERN ANCHOVY, ENGRAULIS MORDAX D. W. RICE, JR.,l F. L. HARRISON,l AND A. JEARLD, JR.2 ABSTRACT The sensitivity to copper of embryonic and larval total copper concentrations and the percent copper in labile forms were determined. From the cumulative

241

Acoustic emission technique used for detecting early stages of precipitation during aging of Inconel 625  

Microsoft Academic Search

Aging behavior of Inconel 625 has been studied at 540 °C. The Ni2(Cr,Mo) phase, found in this material only after a long service life, has been detected along with the ?? phase after a short aging. Acoustic emission technique has been found sensitive enough to detect early stages of precipitation.

J. Mittra; J. S. Dubey; S. Banerjee

2003-01-01

242

Fish early life stage: Developing AOPs to support targeted reduction and replacement  

EPA Science Inventory

There is an interest in developing alternatives to the fish early-life stage (FELS) test (OECD test guideline 210), for predicting adverse chronic toxicity outcomes (e.g., impacts on growth and survival). Development and characterization of adverse outcome pathways (AOPs) related...

243

Late Effects May Not Warrant Using Radiation to Treat Early-Stage Hodgkin Lymphoma  

Cancer.gov

Patients with early-stage Hodgkin lymphoma who were treated with multidrug chemotherapy alone were more likely to be alive 12 years later than patients who received treatment that included radiation therapy, according to findings from a phase III clinical trial.

244

Stainless steel pitting and early-stage stress corrosion cracking under ultra-low elastic load  

E-print Network

Stainless steel pitting and early-stage stress corrosion cracking under ultra-low elastic load, Tampa, FL 33620, USA a r t i c l e i n f o Article history: Received 28 May 2013 Accepted 29 August 2013 Available online 7 September 2013 Keywords: A. Stainless steel B. SEM B. Modeling studies C. Stress

Volinsky, Alex A.

245

Opposing Roles of Dnmt1 in Early- and Late-Stage Murine Prostate Cancer?  

PubMed Central

Previous studies have shown that tumor progression in the transgenic adenocarcinoma of mouse prostate (TRAMP) model is characterized by global DNA hypomethylation initiated during early-stage disease and locus-specific DNA hypermethylation occurring predominantly in late-stage disease. Here, we utilized Dnmt1 hypomorphic alleles to examine the role of Dnmt1 in normal prostate development and in prostate cancer in TRAMP. Prostate tissue morphology and differentiation status was normal in Dnmt1 hypomorphic mice, despite global DNA hypomethylation. TRAMP; Dnmt1 hypomorphic mice also displayed global DNA hypomethylation, but were characterized by altered tumor phenotype. Specifically, TRAMP; Dnmt1 hypomorphic mice exhibited slightly increased tumor incidence and significantly increased pathological progression at early ages and, conversely, displayed slightly decreased tumor incidence and significantly decreased pathological progression at advanced ages. Remarkably, hypomorphic Dnmt1 expression abrogated local and distant site macrometastases. Thus, Dnmt1 has tumor suppressor activity in early-stage prostate cancer, and oncogenic activity in late stage prostate cancer and metastasis. Consistent with the biological phenotype, epigenomic studies revealed that TRAMP; Dnmt1 hypomorphic mice show dramatically reduced CpG island and promoter DNA hypermethylation in late-stage primary tumors compared to control mice. Taken together, the data reveal a crucial role for Dnmt1 in prostate cancer and suggest that Dnmt1-targeted interventions may have utility specifically for advanced and/or metastatic prostate cancer. PMID:20584988

Morey Kinney, Shannon R.; Moser, Michael T.; Pascual, Marien; Greally, John M.; Foster, Barbara A.; Karpf, Adam R.

2010-01-01

246

Differential responses of antioxidant enzymes in pioneer and late-successional tropical tree species grown under sun and shade conditions  

Microsoft Academic Search

To investigate the ability of pioneer and late-successional species to adapt to a strong light environment in a reforestation area, we examined the activities of antioxidant enzymes in relation to photosystem II, chlorophyll a fluorescence and photosynthetic pigment concentration for eight tropical tree species grown under 100% (sun) and 10% (shade) sunlight irradiation. The pioneer (early-succession) species (PS) were Cecropia

Viviane F. Favaretto; Carlos A. Martinez; Hilda H. Soriani; Rosa P. M. Furriel

2011-01-01

247

Accelerating Development of Late Successional Features in Second-Growth Pine Stands of the Goosenest Adaptive Management Area1  

Microsoft Academic Search

This paper describes implementation and early results of a large-scale, interdisciplinary experiment in the Goosenest Adaptive Management Area in northeastern California. The study is designed to investigate development of late-successional forest attributes in second- growth ponderosa pine stands. The experiment has four treatments replicated five times and encompasses 1600 hectares, including controls. Complete treatment implementation took five years, including application

Martin W. Ritchie; Kathleen A. Harcksen

248

Dissection and downstream analysis of zebra finch embryos at early stages of development.  

PubMed

The zebra finch (Taeniopygiaguttata) has become an increasingly important model organism in many areas of research including toxicology, behavior, and memory and learning. As the only songbird with a sequenced genome, the zebra finch has great potential for use in developmental studies; however, the early stages of zebra finch development have not been well studied. Lack of research in zebra finch development can be attributed to the difficulty of dissecting the small egg and embryo. The following dissection method minimizes embryonic tissue damage, which allows for investigation of morphology and gene expression at all stages of embryonic development. This permits both bright field and fluorescence quality imaging of embryos, use in molecular procedures such as in situ hybridization (ISH), cell proliferation assays, and RNA extraction for quantitative assays such as quantitative real-time PCR (qtRT-PCR). This technique allows investigators to study early stages of development that were previously difficult to access. PMID:24999108

Murray, Jessica R; Stanciauskas, Monika E; Aralere, Tejas S; Saha, Margaret S

2014-01-01

249

Analysis of Turbulent flow in early stages of atherosclerosis of coronary artery  

NASA Astrophysics Data System (ADS)

During the early stages of atherosclerotic heart disease, fatty material accumulates in the coronary artery resulting in development of streaks of plaque and creating high levels of turbulence, and with significantly modified flow parameters. Diagnostic measures performed during this early stage may not show any evidence of coronary artery disease, because the lumen of the coronary artery has not decreased in caliber. These streaks do not obstruct the flow of blood but alter the flow characteristics, even at this preclinical stage. This talk presents the preliminary results for the analysis of turbulent flow characteristics for a range of atherosclerotic plaque configurations in the left main coronary artery. For this purpose a CAD/medical imaging based direct-simulation (DNS) tool has been developed. The Navier-stokes equations are solved in the vertical vorticity-velocity formulation. The plaque is introduced using immersed body technique. The geometric acquisition of the artery geometry and plaque morphology is obtained using CAD based commercial software.

Bhaganagar, Kiran

2005-11-01

250

Segmentectomy or lobectomy for early stage lung cancer: a meta-analysis.  

PubMed

Early stage lung cancer is routinely treated by lobectomy whenever clinically feasible, whereas the role of segmentectomy is controversial. The purpose of this study was to investigate the benefits of segmentectomy vs lobectomy for early stage lung cancer through a meta-analysis of published data. Eligible studies were identified from MEDLINE through February 2013. The manual selection of relevant studies was based on the summary analysis. We used published hazard ratios (HRs) if available or estimates from the published survival data. Lobectomy was chosen as the reference in all HR calculations. We compared the effect of segmentectomy and lobectomy for Stage I, Stage IA, Stage IA with tumours larger than 2 cm but smaller than 3 cm in size and Stage IA with tumours of 2 cm or smaller in 22 observational studies. The HRs of overall and cancer-specific survival indicated significant benefits of lobectomy for Stage I, Stage IA and Stage IA with tumours larger than 2 cm but smaller than 3 cm at 1.20 (95% confidence interval [CI] 1.04-1.38; P = 0.011), 1.24 (95% CI 1.08-1.42; P = 0.002) and 1.41 (95% CI 1.14-1.71; P = 0.001), respectively. For tumours 2 cm or smaller, segmentectomy provided an effect equivalent to that of lobectomy (HR 1.05; 95% CI 0.89-1.24; P = 0.550). No significant publication bias was detected in any part of the analysis. These findings should be interpreted in the context of the inherent limitations of meta-analyses of retrospective studies, including the heterogeneity of patient characteristics. PMID:24321996

Bao, Feichao; Ye, Peng; Yang, Yunhai; Wang, Luming; Zhang, Chong; Lv, Xiayi; Hu, Jian

2014-07-01

251

Computer-Aided Diagnosis for Early-Stage Lung Cancer Based on Longitudinal and Balanced Data  

PubMed Central

Background Lung cancer is one of the most common forms of cancer resulting in over a million deaths per year worldwide. Typically, the problem can be approached by developing more discriminative diagnosis methods. In this paper, computer-aided diagnosis was used to facilitate the prediction of characteristics of solitary pulmonary nodules in CT of lungs to diagnose early-stage lung cancer. Methods The synthetic minority over-sampling technique (SMOTE) was used to account for raw data in order to balance the original training data set. Curvelet-transformation textural features, together with 3 patient demographic characteristics, and 9 morphological features were used to establish a support vector machine (SVM) prediction model. Longitudinal data as the test data set was used to evaluate the classification performance of predicting early-stage lung cancer. Results Using the SMOTE as a pre-processing procedure, the original training data was balanced with a ratio of malignant to benign cases of 1?1. Accuracy based on cross-evaluation for the original unbalanced data and balanced data was 80% and 97%, respectively. Based on Curvelet-transformation textural features and other features, the SVM prediction model had good classification performance for early-stage lung cancer, with an area under the curve of the SVMs of 0.949 (P<0.001). Textural feature (standard deviation) showed benign cases had a higher change in the follow-up period than malignant cases. Conclusions With textural features extracted from a Curvelet transformation and other parameters, a sensitive support vector machine prediction model can increase the rate of diagnosis for early-stage lung cancer. This scheme can be used as an auxiliary tool to differentiate between benign and malignant early-stage lung cancers in CT images. PMID:23691066

Sun, Tao; Zhang, Regina; Wang, Jingjing; Li, Xia; Guo, Xiuhua

2013-01-01

252

Characterization of early stage cartilage degradation using diffuse reflectance near infrared spectroscopy  

NASA Astrophysics Data System (ADS)

Interest in localized and early stage treatment technologies for joint conditions such as osteoarthritis is growing rapidly. It has therefore become important to develop objective measures capable of characterizing the earliest (non-visible) changes associated with degeneration to aid treatment procedures. In addition to assessing tissue before treatment, it is further important to develop an effective, non-destructive means of monitoring post-treatment tissue healing, and of providing the high-quality data needed for trials of developing treatment methods. To investigate its ability to detect the early stages of degeneration in cartilage-on-bone, diffuse reflectance near infrared spectroscopy was applied to normal and osteoarthritic joints. A discriminating function was developed to relate absorbance peaks of interest and track degradation around focal osteoarthritic defects. The function could distinguish between normal and degraded tissue (100% separation of normal tissue from that within 25 mm of a defect) and between different stages of osteoarthritic progression (p < 0.05). This technique allows simple, practical and non-destructive assessment of component-level properties over the full depth of the tissue. It has the potential to increase our understanding of the underlying etiologic and pathogenic processes in early stage degeneration, to assist classification and the development of new treatment methods.

Brown, C. P.; Jayadev, C.; Glyn-Jones, S.; Carr, A. J.; Murray, D. W.; Price, A. J.; Gill, H. S.

2011-04-01

253

Distribution of early life history stages of fishes in selected pools of the upper Mississippi River  

USGS Publications Warehouse

Effective management of the fishery resources of the Upper Mississippi River and successful mitigation of the loss of critical habitat depend in part on an understanding of the reproductive and early life history requirements of the affected fishes. However, little is known about the use of nursery areas by fishes in the river. Of the nearly 130 species identified in the adult ichthyofauna, only a few are represented proportionally in the available data on early life stages because study designs have not included consideration of the early stages, collection gears have not adequately sampled the young, and eggs and larvae of some species are difficult to sample by conventional approaches. For the species collected, information is available on seasonal variations in total densities, composition, and catch among different habitat types. However, the data are most accurate for species with buoyant early life stages, such as freshwater drum (Aplodinotus grunniens) and gizzard shad (Dorosoma cepedianum). Eggs and larvae of freshwater drum dominate collections made in the main channel, whereas other larval fishes are usually most abundant in backwater habitats. The species found there usually deposit eggs on the substrate or on vegetation. Habitat preferences (as indicated by relative abundance) often shift as development proceeds and physical and behavioral changes occur in the larvae. Only limited information is available on the distribution of larvae within habitats, but it is clear that variations within habitats are significant.

Holland, L.E.

1986-01-01

254

[Working memory for music in patients with mild cognitive impairment and early stage Alzheimer's disease].  

PubMed

A variety of studies demonstrated that some forms of memory for music are spared in dementia, but only few studies have investigated patients with early stages of dementia. In this pilot-study we tested working memory for music in patients with mild cognitive impairment (MCI) and early stage Alzheimer's disease (AD) with a newly created test. The test probed working memory using 7 gradually elongated tone-lines and 6 chords which were each followed by 3 similar items and 1 identical item. The participants of the study, namely 10 patients with MCI, 10 patients with early stage AD and 23 healthy subjects were instructed to select the identical tone-line or chord. Subjects with MCI and early AD showed significantly reduced performance than controls in most of the presented tasks. In recognizing chords MCI- participants surprisingly showed an unimpaired performance. The gradual increase of the impairment during the preclinical phase of AD seems to spare this special ability in MCI. PMID:23329298

Kerer, Manuela; Marksteiner, Josef; Hinterhuber, Hartmann; Mazzola, Guerino; Kemmler, Georg; Bliem, Harald R; Weiss, Elisabeth M

2013-01-01

255

A large herbivore triggers alternative successional trajectories in the boreal forest.  

PubMed

Alternative successional trajectories (AST) may result in multiple climax states within an ecosystem when disturbances affect colonization history. In the boreal forest, ungulates have been proposed to drive AST because, under herbivore pressure, preferred species may go extinct and apparent competition may benefit browsing-resistant species. Over a 15-year period following logging, we tested whether deer herbivory altered plant species composition and whether the competitive advantage of resistant species was maintained following herbivore removal. We compared exclosures built immediately after logging with delayed exclosures built eight years later on Anticosti Island, Quebec, Canada. Although the palatable tree Betula papyrifera (paper birch) and some palatable herbs recovered in delayed exclosures, we observed legacies in both tree and herb cover. Woody regeneration in delayed exclosures was dominated by Picea glauca (white spruce), and Poaceae (grasses) were abundant in the field layer. Given that only early-successional species recovered, whereas late-successional broadleaf species and Abies balsamea (balsam fir) remained rare, succession may follow an AST after a limited browsing period during early succession. PMID:24597230

Hidding, Bert; Tremblay, Jean-Pierre; Côté, Steeve D

2013-12-01

256

The D-Optimality Item Selection Criterion in the Early Stage of CAT: A Study with the Graded Response Model  

ERIC Educational Resources Information Center

During the early stage of computerized adaptive testing (CAT), item selection criteria based on Fisher"s information often produce less stable latent trait estimates than the Kullback-Leibler global information criterion. Robustness against early stage instability has been reported for the D-optimality criterion in a polytomous CAT with the…

Passos, Valeria Lima; Berger, Martijn P. F.; Tan, Frans E. S.

2008-01-01

257

Radiation treatment after surgery improves survival for elderly women with early-stage breast cancer  

Cancer.gov

Elderly women with early-stage breast cancer live longer with radiation therapy and surgery compared with surgery alone, researchers at the University of Maryland School of Medicine have found. The researchers, who collected data on almost 30,000 women, ages 70 to 84, with early, highly treatable breast cancer enrolled in a nationwide cancer registry, are reporting their findings at the 54th annual meeting of the American Society for Radiation Oncology (ASTRO). The University of Maryland is home to the Greenebaum Cancer Center.

258

Computational simulation of the early stage of bone healing under different configurations of locking compression plates.  

PubMed

Flexible fixation or the so-called 'biological fixation' has been shown to encourage the formation of fracture callus, leading to better healing outcomes. However, the nature of the relationship between the degree of mechanical stability provided by a flexible fixation and the optimal healing outcomes has not been fully understood. In this study, we have developed a validated quantitative model to predict how cells in fracture callus might respond to change in their mechanical microenvironment due to different configurations of locking compression plate (LCP) in clinical practice, particularly in the early stage of healing. The model predicts that increasing flexibility of the LCP by changing the bone-plate distance (BPD) or the plate working length (WL) could enhance interfragmentary strain in the presence of a relatively large gap size (>3 mm). Furthermore, conventional LCP normally results in asymmetric tissue development during early stage of callus formation, and the increase of BPD or WL is insufficient to alleviate this problem. PMID:24261957

Miramini, Saeed; Zhang, Lihai; Richardson, Martin; Pirpiris, Marinis; Mendis, Priyan; Oloyede, Kunle; Edwards, Glenn

2015-06-01

259

Communication in the early stage of language development in children with CHARGE syndrome  

Microsoft Academic Search

CHARGE syndrome is characterized by multiple physical abnormalities, and impaired vision and hearing. In this pilot study, communication in the early stage of language devel- opment in three one- to eight-year-old children with CHARGE syndrome was explored using video recorded free-play interac- tion sessions and a parental questionnaire. The children mainly used gestures, but also vocalization and some signs. According

SINI PELTOKORPI; KERTTU HUTTUNEN

2008-01-01

260

Limited-Field Radiation Therapy in the Management of Early-Stage Breast Cancer  

Microsoft Academic Search

Background: Several phase III trials have demonstrated equivalent long-term survival between breast conserving surgery plus radiation therapy and mastectomy in patients with early-stage breast cancer but have not provided infor- mation on the optimal volume of breast tissue requiring post-lumpectomy radiation therapy. Therefore, we exam- ined the 5-year results of a single institution's experience with radiation therapy limited to the

Frank A. Vicini; Larry Kestin; Peter Chen; Pamela Benitez; Neal S. Goldstein; Alvaro Martinez

2003-01-01

261

Comparison of Favorable Early-Stage Hodgkin's Lymphoma Treatments: A Single-Institution Review  

SciTech Connect

Purpose: To compare outcomes of patients receiving combined-modality chemotherapy and radiation (CMT) vs. other approaches for early-stage Hodgkin's lymphoma (HL). Methods and Materials: A review of patients with nonbulky, early-stage (IA/IIA) HL treated between 1984 and 2002 was performed to determine the treatment approaches used and the outcomes obtained. Results: There were 173 adult patients with newly diagnosed early-stage HL (49% men, 51% women, median age 33 [range 17-82] years). Treatment was as follows: extended-field radiotherapy alone (EFRT) 49%; chemotherapy alone (CTA) 13%; and CMT 38%. Among CMT patients, 36% received abbreviated doxorubicin, bleomycin, vinblastine, and dacarbazine chemotherapy (three to four cycles) followed by involved-field radiotherapy. With a median follow-up of 8.3 years, the estimated 10-year relapse-free survival (RFS) and overall survival (OS) rates for the entire cohort were 78% and 85%, respectively. The 10-year RFS and OS rates for the various groups were as follows: 69% and 81% for EFRT; 78% and 84% for CTA; and 87% and 89% for CMT. The 10-year RFS rate was significantly higher (p < 0.01) among CMT patients. The use of EFRT has diminished from approximately 90% in the 1980s to virtually no use at present, whereas the use of CTA and CMT has increased significantly (p < 0.01). Conclusion: Early-stage HL treatment has changed dramatically over the past 2 decades, and our results support the superiority and continued use of CMT, specifically abbreviated-course chemotherapy and involved-field radiotherapy, as an appropriate treatment approach.

Samant, Rajiv, E-mail: rsamant@ottawahospital.on.c [Division of Radiation Oncology, Ottawa Hospital Cancer Centre, Ottawa, Ontario (Canada); Department of Radiology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario (Canada); Alomary, Ibraheem [Division of Radiation Oncology, Ottawa Hospital Cancer Centre, Ottawa, Ontario (Canada); Department of Radiology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario (Canada); National Guard Health Affairs, Western Region (Saudi Arabia); Alsaeed, Eyad [King Faisal Specialty Hospital, Jeddah (Saudi Arabia); Al-jasir, Badr [Department of Radiology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario (Canada); National Guard Health Affairs, Western Region (Saudi Arabia); Bence-Bruckler, Isabelle [Department of Radiology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario (Canada); Division of Hematology, Ottawa Hospital, Ottawa, Ontario (Canada); Cross, Peter; Genest, Paul [Division of Radiation Oncology, Ottawa Hospital Cancer Centre, Ottawa, Ontario (Canada); Department of Radiology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario (Canada); Huebsch, Lothar [Department of Radiology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario (Canada); Division of Hematology, Ottawa Hospital, Ottawa, Ontario (Canada)

2010-03-15

262

Environmental aspects of VOCs evolved in the early stages of human decomposition  

Microsoft Academic Search

In the present study, the time profile, measured as “accumulation”, of volatile organic compounds (VOCs) produced during the early stages of human decomposition was investigated. A human cadaver was placed in a sealed bag at approximately the 4th day after death. Evolved VOCs were monitored for 24 h by sampling at different time intervals. VOCs produced were analyzed by thermal desorption\\/gas chromatography\\/mass

M. Statheropoulos; A. Agapiou; C. Spiliopoulou; G. C. Pallis; E. Sianos

2007-01-01

263

Photodiscoloration of western hemlock ( Tsuga heterophylla ) sapwood III Early stage of photodiscoloration reaction with lignans  

Microsoft Academic Search

The reaction during the early stage of photodiscoloration of constituents in western hemlock [Tsuga heterophylla (Raf. Sarg., Pinaceae] sapwood was investigated with chemical methods. The main photodiscoloring constituents, hydroxymatairesinol,\\u000a allohydroxymatairesinol, ?-conidendrin, and oxomatairesinol, were used as substrates for light-irradiation experiments in\\u000a vitro. The structures of photodiscoloration reaction products were elucidated by isolation and instrumental analyses and\\/or\\u000a co-high-performance liquid chromatography analyses

Fumio Kawamura; Megumi Miyachi; Shingo Kawai; Hideo Ohashi

1998-01-01

264

Methylation Markers of Early-Stage Non-Small Cell Lung Cancer  

Microsoft Academic Search

BackgroundDespite of intense research in early cancer detection, there is a lack of biomarkers for the reliable detection of malignant tumors, including non-small cell lung cancer (NSCLC). DNA methylation changes are common and relatively stable in various types of cancers, and may be used as diagnostic or prognostic biomarkers.MethodsWe performed DNA methylation profiling of samples from 48 patients with stage

Kaie Lokk; Tõnu Vooder; Raivo Kolde; Kristjan Välk; Urmo Võsa; Retlav Roosipuu; Lili Milani; Krista Fischer; Marina Koltsina; Egon Urgard; Tarmo Annilo; Andres Metspalu; Neeme Tõnisson

2012-01-01

265

Calreticulin enriched as an early-stage encapsulation protein in wax moth Galleria mellonella larvae  

Microsoft Academic Search

To investigate the molecular mechanism of the early-stage encapsulation reaction in insects, we purified a 47kDa protein from injected beads into Galleria mellonella larvae. When a cDNA clone was isolated, the 47kDa protein showed high homology with Drosophila and human calreticulin. Western blotting analysis showed that the 47kDa protein was present in the hemocytes, but not in the plasma. When

J. Y. Choi; M. M. A. Whitten; M. Y. Cho; K. Y. Lee; M. S. Kim; N. A. Ratcliffe; B. L. Lee

2002-01-01

266

Posttreatment biopsy results following interstitial brachytherapy in early-stage prostate cancer  

Microsoft Academic Search

Purpose: To assess pathologic control rates for prostatic carcinoma as determined by postimplant prostate biopsy in a large series of consecutive patients who have received permanent interstitial brachytherapy using a contemporary transrectal ultrasound-directed, transperineal, computer generated, volume technique.Methods and Materials: Four hundred and two patients received permanent 125I or 103Pd interstitial brachytherapy as primary treatment for early stage prostatic carcinoma

Bradley R. Prestidge; David C. Hoak; Peter D. Grimm; Haakon Ragde; William Cavanagh; John C. Blasko

1997-01-01

267

The early stages of the precipitation sequence in nitrided dilute fe-ti alloys  

Microsoft Academic Search

The early stages of the precipitation sequence in nitrided dilute Fe-Ti alloys were investigated by internal friction measurement and electron microscopy. A maximum nitrogen-to-titanium (N\\/Ti) atom ratio of approaching 3 was achieved prior to the formation of stable titanium nitride. A Ti-N clustering process precedes the formation of the substitutional-interstitial Ti-N Guinier-Preston (GP) zone, characterized by the evolution of two

He Kejian; A. Hendry

1992-01-01

268

First-Year Recruitment of Largemouth Bass: The Interdependency of Early Life Stages  

Microsoft Academic Search

Four early life events (i.e., hatching, the ontogenetic diet shift to piscivory, fall lipid accumulation, and the first winter) are conceptualized as being critical to 1st-yr recruitment success of largemouth bass (Micropterus salmoides) via cause-and-effect as- sociations among them. Toward this end, we conducted a multiple life-stage investigation of largemouth bass to examine the functional dependency and significance to recruitment

Stuart A. Ludsin; Dennis R. DeVries

1997-01-01

269

Less invasive treatment associated with improved survival in early stage breast cancer  

Cancer.gov

Patients with early stage breast cancer who were treated with lumpectomy plus radiation may have a better chance of survival compared with those who underwent mastectomy, according to a study from Duke Medicine and the Duke Cancer Institute. The study, which appears online Jan. 28, 2013, in the journal CANCER, raises new questions as to the comparative effectiveness of breast-conserving therapies such as lumpectomy, where only the tumor and surrounding tissue is surgically removed.

270

Longitudinal assessment of BMI in relation to ADT use among early stage prostate cancer survivors  

Microsoft Academic Search

Introduction  The use of androgen deprivation therapy (ADT) for prostate cancer is on the rise, but its adverse side effects may include\\u000a increased fat mass and decreased lean muscle mass. The net effect of ADT on BMI is unknown.\\u000a \\u000a \\u000a \\u000a Methods  Primary, incident cases of early stage prostate cancer (n?=?473) were identified from the Buffalo VA Medical Center tumor registry and matched to

Gregory P. Beehler; Michael Wade; Borah Kim; Lynn Steinbrenner; Laura O. Wray

2009-01-01

271

Effects of Ocean Acidification on Early Life History Stages of Caribbean Scleractinian Corals  

Microsoft Academic Search

Ocean acidification (OA) refers to the increase in acidity (decrease in pH) of the ocean’s surface waters resulting from oceanic uptake of atmospheric carbon dioxide (CO2). Mounting experimental evidence suggests that OA threatens numerous marine organisms, including reef-building corals; however, few studies have focused on the effects on early life history stages. Coral recruitment is critical to the persistence and

Rebecca Albright

2011-01-01

272

A three stage model for the inner engine of GRBs: Prompt emission and early afterglow  

E-print Network

We describe a model within the ``Quark-nova'' scenario to interpret the recent observations of early X-ray afterglows of long Gamma-Ray Bursts (GRB) with the Swift satellite. This is a three-stage model within the context of a core-collapse supernova. STAGE 1 is an accreting (proto-) neutron star leading to a possible delay between the core collapse and the GRB. STAGE 2 is accretion onto a quark-star, launching an ultrarelativistic jet generating the prompt GRB. This jet also creates the afterglow as the jet interacts with the surrounding medium creating an external shock. Slower shells ejected from the quark star (during accretion), can re-energize the external shock leading to a flatter segment in the X-ray afterglow. STAGE 3, which occurs only if the quark-star collapses to form a black-hole, consists of an accreting black-hole. The jet launched in this accretion process interacts with the preceding quark star jet, and could generate the flaring activity frequently seen in early X-ray afterglows. Alternatively, a STAGE 2b can occur in our model if the quark star does not collapse to a black hole. The quark star in this case can then spin down due to magnetic braking, and the spin down energy may lead to flattening in the X-ray afterglow as well. This model seems to account for both the energies and the timescales of GRBs, in addition to the newly discovered early X-ray afterglow features.

Jan Staff; Brian Niebergal; Rachid Ouyed

2007-12-11

273

The Treatment Effect of Porous Titanium Alloy Rod on the Early Stage Talar Osteonecrosis of Sheep  

PubMed Central

Osteonecrosis of the talus (ONT) may severely affect the function of the ankle joint. Most orthopedists believe that ONT should be treated at an early stage, but a concise and effective surgical treatment is lacking. In this study, porous titanium alloy rods were prepared and implanted into the tali of sheep with early-stage ONT (IM group). The curative effect of the rods was compared to treatment by core decompression (DC group). No significant differences in bone reconstruction were observed between the two groups at 1 month after intervention. After 3 months, the macroscopic view of gross specimens of the IM group showed ordinary contours, but the specimens of the DC group showed obvious partial bone defects and cartilage degeneration. Quantitative analysis of the reconstructed trabeculae by micro-CT and histological study suggested that the curative effect of the IM group was superior to that of the DC group at 3 months after intervention. These favorable short-term results of the implantation of porous titanium alloy rods into the tali of sheep with early-stage ONT may provide insight into an innovative surgical treatment for ONT. PMID:23516485

Zhang, Yong-Quan; Zhang, Zhi-Yong; Guo, Zheng

2013-01-01

274

Risk of Fatal Cerebrovascular Accidents after External Beam Radiation Therapy for Early Stage Glottic Larynx Cancer  

PubMed Central

Background This study compared the risk of fatal cerebrovascular accidents (CVA) in patients with early stage glottic larynx cancer receiving surgery or external beam radiation therapy (EBRT). Methods and Materials Using a competing risks survival analysis, we compared the risk of death due to CVA among patients with early stage glottic larynx cancer receiving surgery or EBRT in the SEER database. Results The cumulative incidence of fatal CVA at 15 years was higher in patients receiving EBRT (2.8 %; 95% CI 2.3%–3.4%) compared to surgery (1.5 %; 95% CI 0.8 %–2.3%, p= 0.024). In multivariable competing risks regression models, EBRT remained associated with an increased risk of fatal CVA compared to surgery (adjusted HR 1.75; 95% CI 1.04–2.96, p= 0.037). Conclusion Treatment of early stage glottic larynx cancer with EBRT was associated with a small increase in the risk of late fatal CVA events relative to surgery. PMID:23595858

Swisher-McClure, Samuel; Mitra, Nandita; Lin, Alexander; Ahn, Peter; Wan, Fei; O’Malley, Bert; Weinstein, Gregory S.; Bekelman, Justin E.

2013-01-01

275

Characterization of early stage intermediates in the nucleation phase of A? aggregation.  

PubMed

Alzheimer's disease (AD) is a common form of dementia, which is characterized by the presence of extracellular amyloid plaques comprising the amyloid ? peptide (A?). Although the mechanism underlying AD pathogenesis remains elusive, accumulating evidence suggests that the process of amyloid fibril formation is a surface-mediated event, which plays an important role in AD onset and progression. In this study, the mechanism of A? aggregation on hydrophobic surfaces was investigated with dual polarization interferometry (DPI), which provides real-time information on early stages of the aggregation process. Aggregation was monitored on a hydrophobic C18 surface and a polar silicon oxynitride surface. The DPI results showed a characteristic A? aggregation pattern involving a decrease in the density of A? at the surface followed by an increase in the thickness on the hydrophobic C18 chip. Most importantly, the DPI measurements provided unique information on the early stages of A? aggregation, which is characterized by the presence of initially slow nucleus formation process followed by exponential fibril elongation. The dimensions of the putative nucleus corresponded to a thickness of ?5 nm for both A?40 and A?42, which may represent about 10-15 molecules. The results thus support the nucleation-dependent polymerization model as indicated by the presence of a nucleation phase followed by an exponential growth phase. These results are the first reported measurements of the real-time changes in A? molecular structure during the early stages of amyloid formation at the nanometer level. PMID:22283417

Zhai, Jiali; Lee, Tzong-Hsien; Small, David H; Aguilar, Marie-Isabel

2012-02-14

276

Early oligomerization stages for the non-amyloid component of ?-synuclein amyloid  

NASA Astrophysics Data System (ADS)

In recent years, much effort has focused on the early stages of aggregation and the formation of amyloid oligomers. Aggregation processes for these proteins are complex and their non-equilibrium nature makes any experimental study very difficult. Under these conditions, simulations provide a useful alternative for understanding the dynamics of the early stages of oligomerization. Here, we focus on the non-A? amyloid component (NAC) of the monomer, dimer, and trimer of ?-synuclein, an important 35-residue sequence involved in the aggregation and fibrillation of this protein associated with Parkinson's disease. Using Hamiltonian and temperature replica exchange molecular dynamics simulations combined with the coarse grained Optimized Potential for Efficient peptide structure Prediction potential, we identify the role of the various regions and the secondary structures for the onset of oligomerization. For this sequence, we clearly observe the passage from ?-helix to ?-sheet, a characteristic transition of amyloid proteins. More precisely, we find that the NAC monomer is highly structured with two ?-helical regions, between residues 2-13 and 19-25. As the dimer and trimer form, ?-sheet structures between residues 2-14 and 26-34 appear and rapidly structure the system. The resulting conformations are much more structured than similar dimers and trimers of ?-amyloid and amylin proteins and yet display a strong polymorphism at these early stages of aggregation. In addition to its inherent experimental interest, comparison with other sequences shows that NAC could be a very useful numerical model for understanding the onset of aggregation.

Eugene, Cindie; Laghaei, Rozita; Mousseau, Normand

2014-10-01

277

Expansion of CTCs from early stage lung cancer patients using a microfluidic co-culture model.  

PubMed

The potential utility of circulating tumor cells (CTCs) to guide clinical care in oncology patients has gained momentum with emerging micro- and nanotechnologies. Establishing the role of CTCs in tumor progression and metastasis depends both on enumeration and on obtaining sufficient numbers of CTCs for downstream assays. The numbers of CTCs are few in early stages of cancer, limiting detailed molecular characterization. Recent attempts in the literature to culture CTCs isolated from metastatic patients using monoculture have had limited success rates of less than 20%. Herein, we have developed a novel in-situ capture and culture methodology for ex-vivo expansion of CTCs using a three dimensional co-culture model, simulating a tumor microenvironment to support tumor development. We have successfully expanded CTCs isolated from 14 of 19 early stage lung cancer patients. Expanded lung CTCs carried mutations of the TP53 gene identical to those observed in the matched primary tumors. Next-generation sequencing further revealed additional matched mutations between primary tumor and CTCs of cancer-related genes. This strategy sets the stage to further characterize the biology of CTCs derived from patients with early lung cancers, thereby leading to a better understanding of these putative drivers of metastasis. PMID:25474037

Zhang, Zhuo; Shiratsuchi, Hiroe; Lin, Jules; Chen, Guoan; Reddy, Rishindra M; Azizi, Ebrahim; Fouladdel, Shamileh; Chang, Andrew C; Lin, Lin; Jiang, Hui; Waghray, Meghna; Luker, Gary; Simeone, Diane M; Wicha, Max S; Beer, David G; Ramnath, Nithya; Nagrath, Sunitha

2014-12-01

278

Ontogenetic development in the morphology and behavior of loach ( Misgurnus anguillicaudatus) during early life stages  

NASA Astrophysics Data System (ADS)

Loach ( Misgurnus anguillicaudatus) are a commercially important fish in China and an ideal aquaculture species. However, culturists experience high larval and juvenile mortality during mass production. To provide insight into ways to improve larviculture techniques, we describe the morphological characteristics and behavior of loach during the larval and early juvenile stages. Yolksac larvae ranged from 2.8 to 4.0 mm body length (BL) between days 0 to 4; preflexion larvae ranged from 3.6 to 5.5 mm BL between days 4 to 6; flexion larvae ranged from 4.8 to 8.1 mm BL between days 5 and 14; and postflexion larvae ranged from 7.1 to 15.7 mm BL between days 11 to 27; the minimum length and age of juveniles was 14.1 mm BL and 23 d, respectively. Loach are demersal from hatch through to the early juvenile stages. A suite of morphological characteristics (e.g., external gill filament and ventral mouth opening) and behavioral traits have developed to adapt to demersal living. We observed positive allometric growth in eye diameter, head length, head height, and pectoral fin length during the early larval stages, reflecting the priorities in the development of the organs essential for survival. Our results provide a basis for developing techniques to improve the survival of larval and juvenile loach during mass production.

Gao, Lei; Duan, Ming; Cheng, Fei; Xie, Songguang

2014-09-01

279

Expansion of CTCs from early stage lung cancer patients using a microfluidic co-culture model  

PubMed Central

The potential utility of circulating tumor cells (CTCs) to guide clinical care in oncology patients has gained momentum with emerging micro- and nanotechnologies. Establishing the role of CTCs in tumor progression and metastasis depends both on enumeration and on obtaining sufficient numbers of CTCs for downstream assays. The numbers of CTCs are few in early stages of cancer, limiting detailed molecular characterization. Recent attempts in the literature to culture CTCs isolated from metastatic patients using monoculture have had limited success rates of less than 20%. Herein, we have developed a novel in-situ capture and culture methodology for ex-vivo expansion of CTCs using a three dimensional co-culture model, simulating a tumor microenvironment to support tumor development. We have successfully expanded CTCs isolated from 14 of 19 early stage lung cancer patients. Expanded lung CTCs carried mutations of the TP53 gene identical to those observed in the matched primary tumors. Next-generation sequencing further revealed additional matched mutations between primary tumor and CTCs of cancer-related genes. This strategy sets the stage to further characterize the biology of CTCs derived from patients with early lung cancers, thereby leading to a better understanding of these putative drivers of metastasis. PMID:25474037

Zhang, Zhuo; Shiratsuchi, Hiroe; Lin, Jules; Chen, Guoan; Reddy, Rishindra M.; Azizi, Ebrahim; Fouladdel, Shamileh; Chang, Andrew C.; Lin, Lin; Jiang, Hui; Waghray, Meghna; Luker, Gary; Simeone, Diane M.; Wicha, Max S.; Beer, David G.; Ramnath, Nithya; Nagrath, Sunitha

2014-01-01

280

Effects of Columbia River water on early life-stages of white sturgeon (Acipenser transmontanus).  

PubMed

The white sturgeon (Acipenser transmontanus) population that resides in the Columbia River in British Columbia (BC), Canada, has suffered recruitment failures for more than three decades. During the summers of 2008 and 2009, studies were performed to determine whether exposure to water downstream of a metal smelter in Trail, BC affected survival or growth of early life-stages of white sturgeon through 60+ days post-fertilization (dpf). In both years, there were no significant differences in survival of fish that were exposed to water from downstream compared to water from upstream of the smelter. At 20-21dpf, average mortality was 2.4 percent and 12 percent in upstream water for 2008 and 2009, respectively, which was similar to the average mortality of 3.8 percent and 7.2 percent in downstream water for 2008 and 2009, respectively. Relatively great mortality after 20-21dpf complicated analysis of the subchronic exposure, but use of a survival analysis indicated that the average fish died at 25-29dpf, regardless of whether the water to which they were exposed came from upstream or downstream of the smelter. In addition, measured concentrations of metals in river water were less than the threshold for adverse effects on early life stages of white sturgeon. Based upon these analyses, it is not likely that current concentrations of metals in the Columbia River in southern BC are adversely affecting survival of early life stages of white sturgeon larvae. PMID:24507122

Tompsett, Amber R; Vardy, David W; Higley, Eric; Doering, Jon A; Allan, Marcie; Liber, Karsten; Giesy, John P; Hecker, Markus

2014-03-01

281

An Analytical Theory for the Early Stage of the Development of Hurricanes: Part II  

E-print Network

In this series of papers, an analytical theory for the early stage (tropical storm stage) of hurricane development is proposed. In Part I, a linear theory and a nonlinear theory have been formulated. It was found in Part I that the linear theory, a kind of the 2D Rankine vortex, gives some unrealistic properties for hurricane development at the upper half of the atmosphere. In the nonlinear theory, the analytical solutions agree well in many dynamical respects with observations at the tropical stage of hurricane development. Particularly, these solutions offer new insights which have not been shown before. However, this nonlinear theory has a disturbing point: a discontinuity of tangential wind and geopotential with radius. In this second Part, this discontinuity will be eliminated satisfactorily without any significant changes to the results obtained in Part I. In addition, the frictional effects will be investigated, which has not been done considered in Part I.

Takata, J; Hirotani, K

2004-01-01

282

[Comparative characterization of mesenchymal bone marrow stromal cells at early and late stages of culturing].  

PubMed

The mesenchymal stromal cell is a multipotent precursor of osteoblasts, adipocytes, and some other cell types. In this study, a comparative analysis of cultured mesenchymal stromal cells from the rat bone marrow at the early and late stages of subculturing has been performed using molecular genetic and cytological methods. The culture has undergone 11 passages during 140 days. Upon long-term culturing, the mesenchymal stromal cells have proved to lose their potential for adipogenic differentiation but preserve the potential for osteogenesis. Morphological characters typical of osteogenic differentiation can be observed at the earlier stages of culturing (passages 1-4) but disappear at later stages (passages 9-11), despite mineralization of the extracellular matrix and the expression of osteogenic differentiation markers. A comparative analysis of the proliferation potential of stromal cells has shown that differences in the period of cell population doubling at the early and later stages of culturing are insignificant. An almost complete arrest of cell growth has been observed in the middle of the culture period (passages 5 and 6). PMID:18946989

Kozhevnikova, M N; Mikaelian, A S; Paiushina, O V; Starostin, V I

2008-01-01

283

Development sites, feeding modes and early stages of seven European Palloptera species (Diptera, Pallopteridae).  

PubMed

Two hundred and ninety-eight rearing records and 87 larvae and puparia were obtained of seven species of Palloptera Fallén (Diptera, Pallopteridae), mainly in Scotland during 2012-2013. The third stage larva and puparium of each species were assessed morphologically and development sites and feeding modes investigated by rearing, observation and feeding tests. Early stages appear to be distinguished by the swollen, apico-lateral margins of the prothorax which are coated in vestiture and a poorly developed anal lobe with few spicules. Individual pallopteran species are separated by features of the head skeleton, locomotory spicules and the posterior respiratory organs. Five species can be distinguished by unique character states. Observations and feeding tests suggest that the frequently cited attribute of zoophagy is accidental and that saprophagy is the primary larval feeding mode with autumn/winter as the main period of development. Food plants were confirmed for flowerhead and stem developing species and rain is important for maintaining biofilms on which larvae feed. Due to difficulties in capturing adults, especially males, the distribution and abundance of many pallopteran species is probably underestimated. Better informed estimates are possible if early stages are included in biodiversity assessments. To facilitate this for the species investigated, a key to the third stage larva and puparium along with details on finding them, is provided.  PMID:25543723

Rotheray, Graham E

2014-01-01

284

Successional distance between the source and recipient influence seed germination and seedling survival during surface soil replacement in SW China.  

PubMed

Adding propagules (source) to a degraded site (recipient) is a common way of manipulating secondary succession to restore diversity and services formerly provided by forests. However, heretofore no study has considered the effect of "successional distance" between source and recipient site. Four sites in the Shilin karst area of SW China were treated as different states along a secondary successional sere: grass, shrub, young secondary forest, and primary forest. Ten 1 m ×1m soil quadrats in the grass, shrub and young forest sites were replaced with 10 cm deep soil sources from corresponding later successional stage(s) in January 2009. Woody plant seed germination was monitored in the first year and seedling survival was monitored until the end of the second year. At the end of 2010, 2097 seeds of woody plants belonging to 45 taxa had germinated, and 3.9% of the seedlings and 7.8% of the species survived. Germination of most species was sensitive to ambient light (red, far-red, R:FR ratios, photosynthetically active radiation). Soil source and recipient site had a significant effect on the total number of seeds and number of species that germinated, and on the percentage of seedlings that survived through the end of the second year. Closer successional stages between recipient site and soil source had higher seed germination and seedling-survival percentages. However, a transition threshold exists in the young forest state, where seeds can germinate but not survive the second year. Our results, although based on an unreplicated chronosequence, suggest that successional distance between soil sources and recipient sites affect forest recruitment and restoration in degraded karst of SW China. PMID:24223891

Shen, You-Xin; Gao, Lei; Xia, Xue; Li, Yuhui; Guan, Huilin

2013-01-01

285

Maspin is a marker for early recurrence in primary stage III and IV colorectal cancer  

PubMed Central

Background: Little is known about the factors that drive metastasis formation in colorectal cancer (CRC). Here, we set out to identify genes and proteins in patients with colorectal liver metastases that correlate with early disease recurrence. Such factors may predict a propensity for metastasis in earlier stages of CRC. Methods: Gene expression profiling and proteomics were used to identify differentially expressed genes/proteins in resected liver metastases that recurred within 6 months following liver surgery vs those that did not recur for >24 months. Expression of the identified genes/proteins in stage II (n=243) and III (n=176) tumours was analysed by immunohistochemistry on tissue microarrays. Correlation of protein levels with stage-specific outcome was assessed by uni- and multivariable analyses. Results: Both gene expression profiling and proteomics identified Maspin to be differentially expressed in colorectal liver metastases with early (<6 months) and prolonged (>24 months) time to recurrence. Immunohistochemical analysis of Maspin expression on tumour sections revealed that it was an independent predictor of time to recurrence (log-rank P=0.004) and CRC-specific survival (P=0.000) in stage III CRC. High Maspin expression was also correlated with mucinous differentiation. In stage II CRC patients, high Maspin expression did not correlate with survival but was correlated with a right-sided tumour location. Conclusion: High Maspin expression correlates with poor outcome in CRC after spread to the local lymph nodes. Therefore, Maspin may have a stage-specific function possibly related to tumour cell dissemination and/or metastatic outgrowth. PMID:24002600

Snoeren, N; Emmink, B L; Koerkamp, M J G; van Hooff, S R; Goos, J A C M; van Houdt, W J; de Wit, M; Prins, A M; Piersma, S R; Pham, T V; Belt, E J; Bril, H; Stockmann, H B; Meijer, G A; van Hillegersberg, R; Holstege, F C; Jimenez, C R; Fijneman, R J A; Kranenburg, O W; Rinkes, I H M Borel

2013-01-01

286

Abnormalities of plantar pressure distribution in early, intermediate, and late stages of diabetic neuropathy.  

PubMed

Inconsistent findings with regard to plantar pressure while walking in the diabetic population may be due to the heterogeneity of the studied groups resulting from the classification/grouping criteria adopted. The clinical diagnosis and classification of diabetes have inherent uncertainties that compromise the definition of its onset and the differentiation of its severity stages. A fuzzy system could improve the precision of the diagnosis and classification of diabetic neuropathy because it takes those uncertainties into account and combines different assessment methods. Here, we investigated how plantar pressure abnormalities evolve throughout different severity stages of diabetic polyneuropathy (absent, n=38; mild, n=20; moderate, n=47; severe, n=24). Pressure distribution was analysed over five areas while patients walked barefoot. Patients with mild neuropathy displayed an increase in pressure-time integral at the forefoot and a lower peak pressure at the heel. The peak and pressure-time integral under the forefoot and heel were aggravated in later stages of the disease (moderate and severe) compared with early stages of the disease (absent and mild). In the severe group, lower pressures at the lateral forefoot and hallux were observed, which could be related to symptoms that develop with the aggravation of neuropathy: atrophy of the intrinsic foot muscles, reduction of distal muscle activity, and joint stiffness. Although there were clear alterations over the forefoot and in a number of plantar areas with higher pressures within each severity stage, they did not follow the aggravation evolution of neuropathy classified by the fuzzy model. Based on these results, therapeutic interventions should begin in the early stages of this disease to prevent further consequences of the disease. PMID:25086801

Sacco, Isabel C N; Hamamoto, Adriana N; Tonicelli, Lucas M G; Watari, Ricky; Ortega, Neli R S; Sartor, Cristina D

2014-09-01

287

Litterfall production along successional and altitudinal gradients of subtropical monsoon evergreen broadleaved forests in Guangdong, China  

USGS Publications Warehouse

Evaluation of litterfall production is important for understanding nutrient cycling, forest growth, successional pathways, and interactions with environmental variables in forest ecosystems. Litterfall was intensively studied during the period of 1982-2001 in two subtropical monsoon vegetation gradients in the Dinghushan Biosphere Reserve, Guangdong Province, China. The two gradients include: (1) a successional gradient composed of pine forest (PF), mixed pine and broadleaved forest (MF) and monsoon evergreen broadleaved forest (BF), and (2) an altitudinal gradient composed of Baiyunci ravine rain forest (BRF), Qingyunci ravine rain forest (QRF), BF and mountainous evergreen broadleaved forest (MMF). Mean annual litterfall production was 356, 861 and 849 g m-2 for PF, MF and BF of the successional gradient, and 1016, 1061, 849 and 489 g m-2 for BRF, QRF, BF and MMF of the altitudinal gradient, respectively. As expected, mean annual litterfall of the pioneer forest PF was the lowest, but rapidly increased over the observation period while those in other forests were relatively stable, confirming that forest litterfall production is closely related to successional stages and growth patterns. Leaf proportions of total litterfall in PF, MF, BF, BRF, QRF and MMF were 76.4%, 68.4%, 56.8%, 55.7%, 57.6% and 69.2%, respectively, which were consistent with the results from studies in other evergreen broadleaved forests. Our analysis on litterfall monthly distributions indicated that litterfall production was much higher during the period of April to September compared to other months for all studied forest types. Although there were significant impacts of some climate variables (maximum and effective temperatures) on litterfall production in some of the studied forests, the mechanisms of how climate factors (temperature and rainfall) interactively affect litterfall await further study. ?? 2006 Springer Science+Business Media B.V.

Zhou, G.; Guan, L.; Wei, X.; Zhang, D.; Zhang, Q.; Yan, J.; Wen, D.; Liu, J.; Liu, S.; Huang, Z.; Kong, G.; Mo, J.; Yu, Q.

2007-01-01

288

Narrowband Ultraviolet B Phototherapy of Early Stage Mycosis Fungoides in Korean Patients  

PubMed Central

Background Narrowband UVB (NBUVB) is currently used to treat early mycosis fungoides (MF). There are a number of reports on the efficacy and safety of NBUVB in Caucasians, but little data is available for Asians. Objective This study was designed to evaluate the effectiveness and safety of NBUVB for early stage MF in Korean patients. Methods We enrolled 14 patients (12 men, 2 women; age range, 10~64 years) with clinically and histologically proven MF. Three patients were stage IA, and the others were stage IB. The patients received NBUVB phototherapy three times a week. The starting dose was 70% of the minimal erythema dose and was increased in 20 percent increments if the previous treatment did not cause erythema. Clinical response, total number of treatments, total cumulative dose, duration of remission and side effects were investigated. Results Eleven of 14 patients (78.6%) achieved complete remission within a mean of 15.36±5.71 weeks (range, 5~27 weeks), 31.0±7.4 treatments (range, 16~39 treatments) and a mean cumulative UVB dose of 31.31±12.16 J/cm2 (range, 11.4~46.8 J/cm2). Three of the 14 patients (21.4%) achieved a partial remission. After discontinuation of treatment, 6 of 11 patients (54.5%) with complete remission relapsed after a mean of 8.5±4.09 months. No serious adverse effects were observed except for hyperpigmentation (7/14, 50%). Conclusion Our data suggest that NBUVB therapy is safe and effective for the treatment of early stage MF in Korean patients. PMID:22148015

Jang, Min Soo; Baek, Jae Woo; Park, Jong Bin; Kang, Dong Young; Kang, Jin Seuk; Suh, Kee Suck

2011-01-01

289

Dissection and Downstream Analysis of Zebra Finch Embryos at Early Stages of Development  

PubMed Central

The zebra finch (Taeniopygiaguttata) has become an increasingly important model organism in many areas of research including toxicology1,2, behavior3, and memory and learning4,5,6. As the only songbird with a sequenced genome, the zebra finch has great potential for use in developmental studies; however, the early stages of zebra finch development have not been well studied. Lack of research in zebra finch development can be attributed to the difficulty of dissecting the small egg and embryo. The following dissection method minimizes embryonic tissue damage, which allows for investigation of morphology and gene expression at all stages of embryonic development. This permits both bright field and fluorescence quality imaging of embryos, use in molecular procedures such as in situ hybridization (ISH), cell proliferation assays, and RNA extraction for quantitative assays such as quantitative real-time PCR (qtRT-PCR). This technique allows investigators to study early stages of development that were previously difficult to access. PMID:24999108

Murray, Jessica R.; Stanciauskas, Monika E.; Aralere, Tejas S.; Saha, Margaret S.

2014-01-01

290

Measurement of the human esophageal cancer in an early stage with Raman spectroscopy  

NASA Astrophysics Data System (ADS)

The esophageal cancer has a tendency to transfer to another part of the body and the surgical operation itself sometimes gives high risk in vital function because many delicate organs exist near the esophagus. So the esophageal cancer is a disease with a high mortality. So, in order to lead a higher survival rate five years after the cancer's treatment, the investigation of the diagnosis methods or techniques of the cancer in an early stage and support the therapy are required. In this study, we performed the ex vivo experiments to obtain the Raman spectra from normal and early-stage tumor (stage-0) human esophageal sample by using Raman spectroscopy. The Raman spectra are collected by the homemade Raman spectrometer with the wavelength of 785 nm and Raman probe with 600-um-diameter. The principal component analysis (PCA) is performed after collection of spectra to recognize which materials changed in normal part and cancerous pert. After that, the linear discriminant analysis (LDA) is performed to predict the tissue type. The result of PCA indicates that the tumor tissue is associated with a decrease in tryptophan concentration. Furthermore, we can predict the tissue type with 80% accuracy by LDA which model is made by tryptophan bands.

Maeda, Yasuhiro; Ishigaki, Mika; Taketani, Akinori; Andriana, Bibin B.; Ishihara, Ryu; Sato, Hidetoshi

2014-02-01

291

Large spinose microfossils in Ediacaran rocks as resting stages of early animals  

PubMed Central

Large (>100 ?m), profusely ornamented microfossils comprise a distinctive paleontological component of sedimentary rocks deposited during the Ediacaran Period (635–542 million years ago). Smaller spinose fossils in Paleozoic rocks have commonly been interpreted as algal cysts or phycomata, but the Ediacaran populations differ from modern algal analogs in size, shape, ultrastructure, and internal contents. In contrast, cysts formed during the diapause egg-resting stages of many metazoans share features of size, ornamentation, and internal contents with large ornamented Ediacaran microfossils (LOEMs). Moreover, transmission electron microscopic observations of animal-resting cysts reveal a 3-layer wall ultrastructure comparable to that of LOEM taxa. Interpretation of these distinctive Ediacaran microfossils as resting stages in early metazoan life cycles offers additional perspectives on their functional morphology and stratigraphic distribution. Based on comparisons with modern marine invertebrates, the recalcitrant life stage represented by LOEMs is interpreted as an evolutionary response to prolonged episodes of bottom water anoxia in Ediacaran shelf and platform environments. As predicted by this hypothesis, the later Ediacaran disappearance of LOEM taxa coincides with geochemical evidence for a marked decline in the extent of oxygen-depleted waters impinging on continental shelves and platforms. Thus, the form, diversity, and stratigraphic range of LOEMs illuminate life cycle evolution in early animals as influenced by the evolving redox state of the oceans. PMID:19366668

Cohen, Phoebe A.; Knoll, Andrew H.; Kodner, Robin B.

2009-01-01

292

Changes of statistical structural fluctuations unveils an early compacted degraded stage of PNS myelin  

NASA Astrophysics Data System (ADS)

Degradation of the myelin sheath is a common pathology underlying demyelinating neurological diseases from Multiple Sclerosis to Leukodistrophies. Although large malformations of myelin ultrastructure in the advanced stages of Wallerian degradation is known, its subtle structural variations at early stages of demyelination remains poorly characterized. This is partly due to the lack of suitable and non-invasive experimental probes possessing sufficient resolution to detect the degradation. Here we report the feasibility of the application of an innovative non-invasive local structure experimental approach for imaging the changes of statistical structural fluctuations in the first stage of myelin degeneration. Scanning micro X-ray diffraction, using advances in synchrotron x-ray beam focusing, fast data collection, paired with spatial statistical analysis, has been used to unveil temporal changes in the myelin structure of dissected nerves following extraction of the Xenopus laevis sciatic nerve. The early myelin degeneration is a specific ordered compacted phase preceding the swollen myelin phase of Wallerian degradation. Our demonstration of the feasibility of the statistical analysis of SµXRD measurements using biological tissue paves the way for further structural investigations of degradation and death of neurons and other cells and tissues in diverse pathological states where nanoscale structural changes may be uncovered.

Poccia, Nicola; Campi, Gaetano; Ricci, Alessandro; Caporale, Alessandra S.; di Cola, Emanuela; Hawkins, Thomas A.; Bianconi, Antonio

2014-06-01

293

Drug Repositioning Discovery for Early- and Late-Stage Non-Small-Cell Lung Cancer  

PubMed Central

Drug repositioning is a popular approach in the pharmaceutical industry for identifying potential new uses for existing drugs and accelerating the development time. Non-small-cell lung cancer (NSCLC) is one of the leading causes of death worldwide. To reduce the biological heterogeneity effects among different individuals, both normal and cancer tissues were taken from the same patient, hence allowing pairwise testing. By comparing early- and late-stage cancer patients, we can identify stage-specific NSCLC genes. Differentially expressed genes are clustered separately to form up- and downregulated communities that are used as queries to perform enrichment analysis. The results suggest that pathways for early- and late-stage cancers are different. Sets of up- and downregulated genes were submitted to the cMap web resource to identify potential drugs. To achieve high confidence drug prediction, multiple microarray experimental results were merged by performing meta-analysis. The results of a few drug findings are supported by MTT assay or clonogenic assay data. In conclusion, we have been able to assess the potential existing drugs to identify novel anticancer drugs, which may be helpful in drug repositioning discovery for NSCLC. PMID:25210704

Chang, Peter Mu-Hsin; Lin, Yong-Jie; Wang, Cheng-Hsu; Huang, Chi-Ying F.

2014-01-01

294

Accelerated Partial Breast Irradiation Using Only Intraoperative Electron Radiation Therapy in Early Stage Breast Cancer  

SciTech Connect

Background: We report the results of a single-institution, phase II trial of accelerated partial breast irradiation (APBI) using a single dose of intraoperative electron radiation therapy (IOERT) in patients with low-risk early stage breast cancer. Methods and Materials: A cohort of 226 patients with low-risk, early stage breast cancer were treated with local excision and axillary management (sentinel node biopsy with or without axillary node dissection). After the surgeon temporarily reapproximated the excision cavity, a dose of 21 Gy using IOERT was delivered to the tumor bed, with a margin of 2 cm laterally. Results: With a mean follow-up of 46 months (range, 28-63 months), only 1 case of local recurrence was reported. The observed toxicity was considered acceptable. Conclusions: APBI using a single dose of IOERT can be delivered safely in women with early, low-risk breast cancer in carefully selected patients. A longer follow-up is needed to ascertain its efficacy compared to that of the current standard treatment of whole-breast irradiation.

Maluta, Sergio [Department of Radiation Oncology, University Hospital, Verona (Italy)] [Department of Radiation Oncology, University Hospital, Verona (Italy); Dall'Oglio, Stefano, E-mail: stefano.dalloglio@ospedaleuniverona.it [Department of Radiation Oncology, University Hospital, Verona (Italy)] [Department of Radiation Oncology, University Hospital, Verona (Italy); Marciai, Nadia; Gabbani, Milena [Department of Radiation Oncology, University Hospital, Verona (Italy)] [Department of Radiation Oncology, University Hospital, Verona (Italy); Franchini, Zeno [Department of Surgery 1, University Hospital, Verona (Italy)] [Department of Surgery 1, University Hospital, Verona (Italy); Pietrarota, Paolo [Department of Surgery 2, University Hospital, Verona (Italy)] [Department of Surgery 2, University Hospital, Verona (Italy); Meliado, Gabriele; Guariglia, Stefania; Cavedon, Carlo [Department of Health Physics, University Hospital, Verona (Italy)] [Department of Health Physics, University Hospital, Verona (Italy)

2012-10-01

295

Experimental early-stage coalification of a peat sample and a peatified wood sample from Indonesia  

USGS Publications Warehouse

Experimental coalification of a peat sample and a buried wood sample from domed peat deposits in Indonesia was carried out to examine chemical structural changes in organic matter during early-stage coalification. The experiment (125 C, 408 atm lithostatic pressure, and 177 atm fluid pressure for 75 days) was designed to maintain both lithostatic and fluid pressure on the sample, but allow by-products that may retard coalification to escape. We refer to this design as a geologically open system. Changes in the elemental composition, and 13C NMR and FTIR spectra of the peat and wood after experimental coalification suggest preferential thermal decomposition of O-containing aliphatic organic compounds (probably cellulose) during early-stage coalification. The elemental compositions and 13C NMR spectra of the experimentally coalified peat and wood were generally similar to those of Miocene coal and coalified wood samples from Indonesia. Yields of lignin phenols in the peat and wood samples decreased following experimental coalification; the wood sample exhibited a larger change. Lignin phenol yields from the experimentally coalified peat and wood were comparable to yields of lignin phenols from Miocene Indonesian lignite and coalified wood. Changes in syringyl/vanillyl and p-hydroxy/vanillyl ratios suggest direct demethoxylation as a secondary process to demethylation of methoxyl groups during early coalification, and changes in lignin phenol yields and acid/aldehyde ratios point to a coupling between demethoxylation processes and reactions in the alkyl side chain bonds of the ??-carbon in lignin phenols.

Orem, W.H.; Neuzil, S.G.; Lerch, H.E.; Cecil, C.B.

1996-01-01

296

The Early Stages of Taxol Biosynthesis: An Interim Report on the Synthesis and Identification of Early Pathway Metabolites  

PubMed Central

The biosynthesis of the anti-cancer drug taxol (paclitaxel) has required the collaborative efforts of several research groups to tackle the synthesis and labeling of putative biosynthetic intermediates, in concert with the identification, cloning and functional expression of the biosynthetic genes responsible for the construction of this complex natural product. Based on a combination of precursor labeling and incorporation experiments, and metabolite isolation from Taxus spp., a picture of the complex matrix of pathway oxygenation reactions following formation of the first committed intermediate, taxa-4(5),11(12)-diene, is beginning to emerge. An overview of the current state of knowledge on the early-stages of taxol biosynthesis is presented. PMID:22547034

Guerra-Bubb, Jennifer; Croteau, Rodney; Williams, Robert M.

2012-01-01

297

OLD FIELD SUCCESSIONAL DYNAMICS FOLLOWING CESSATION OF CHRONIC DISTURBANCE  

EPA Science Inventory

In grasslands dominated by warm-season grasses, community composition and successional patterns can be altered by disturbance and exotic species invasions. Our objective was to describe vegetation dynamics following cessation of a chronic disturbance (heavy grazing by cattle) in...

298

The potential role of extracellular regulatory kinase in the survival of patients with early stage adenocarcinoma  

PubMed Central

Background Lung cancer is among the most common types of neoplasias, and adenocarcinoma is the most frequent histological type. There is currently an extensive search for prognostic biomarkers of nonsmall cell lung cancer (NSCLC). Methods We analyzed the correlation of clinical data and patient survival with the levels of activated extracellular regulatory kinase (ERK) in histological samples of surgically resected early stage lung adenocarcinoma. We randomly selected 36 patients with stage I or II lung adenocarcinoma who underwent pulmonary lobectomy between 1998 and 2004. Patients were divided into the following two groups according to immunohistochemical profile: a group with <15% ERK-positive tumor cells and a group with ?15% ERK-positive tumor cells. For data comparison, an enrichment analysis of a microarray database was performed (GSE29016, n=72). Results Activated ERK levels were ?15% and <15% in 21 (58%) and 15 (42%) patients, respectively. There were no statistically significant differences in age, sex, smoking history, and body mass index (BMI) among the groups stratified by ERK levels. The survival rate was lower in the ERK ?15% group than in the ERK <15% group (P=0.045). Enrichment analyses showed no correlation between variations in gene expression of ERK in patients with adenocarcinoma and survival rates in patients with stage I and combined stage II + III disease. Conclusions Our findings suggest that high ERK positivity in cells from biological samples of lung adenocarcinoma is related with tumor aggressiveness and a poorer prognosis. PMID:25093089

de Leon Martini, Simone; Müller, Carolina Beatriz; Meurer, Rosalva Thereza; Fernandes, Marilda da Cruz; Mariano, Rodrigo; Barbachan e Silva, Mariel; Klamt, Fábio

2014-01-01

299

Supradiaphragmatic early stage Hodgkin's disease: does mantle radiation therapy still have a role?  

PubMed

Extended field radiation therapy represents the main therapeutic option in early stage Hodgkin's disease with favorable prognostic features. Its role however has recently been criticized, mainly due to the high incidence of late complications in irradiated tissues. Furthermore, surgical staging, which in the opinion of many is mandatory for proper selection of patients for radiotherapy alone, has a well-known morbidity, and splenectomy has been associated with a high risk of secondary leukemias. Lastly, the failure rate after radiotherapy only is not negligible and second-line treatment is not always successful. A review of our experience and of the recent literature has allowed us to refute these objections. The results of radiotherapy, when properly performed, are highly reliable and have been reproducible in many Institutions. Chemotherapy alone cannot yet be regarded as an alternative to radiotherapy in these patients since data reported on this issue are conflicting. Present knowledge regarding the relationship between clinical features and the risk of occult subdiaphragmatic spread allows patients with localized disease to be selected without surgical staging; the results of radiotherapy in clinically staged patients confirm this statement. Concern for the late effects in irradiated tissues is justified, and future efforts should be directed at reducing the toxicity of this treatment. Associating a short chemotherapy course with low-dose radiotherapy to involved sites could help to achieve this goal. PMID:8641642

Frezza, G; Barbieri, E; Zinzani, P L; Babini, L; Tura, S

1996-01-01

300

Stages in the early and larval development of the African catfish Clarias gariepinus (Teleostei, Clariidae).  

PubMed

The African catfish Clarias gariepinus Burchell 1822 is a favourite aquaculture fish in many parts of Africa and Asia because of its hardiness and fast growth rate. In this study, early, post-embryonic and larval developmental stages of C. gariepinus were examined chronologically and described. Photomicrographs of unfertilized matured oocytes from 0 min of fertilization through all cell stages to alevin, to complete yolk absorption, to free swimming larval stages are shown and documented live from lateral and top views, with the aid of a light microscope. Extruded oocytes had a mean diameter of 1 ± 0.1 mm, and possessed a thin perivitelline membrane whose space was filled with a protoplasmic layer. Heartbeat was in the range of 115-160/min prior to hatching. Hatchability rate was 85% and hatching occurred at 17 h at a controlled temperature of 28.5 ± 0.5°C, while ontogeny of the eyes and other organs were discernible. At day 4, larvae mean length was 9.3 ± 0.5 mm, exogenous feeding had commenced fully and melanophores spread cephalocaudally but were concentrated significantly on the head parts. This paper, for the first time, presents the significant chronological developmental stages of C. gariepinus embryology that will have significant implications for genetic manipulation and catfish seed production for aquaculture. PMID:23534899

Olaniyi, Wasiu Adekunle; Omitogun, Ofelia Galman

2014-08-01

301

Miniprobe Endoscopic Ultrasonography Has Limitations in Determining the T Stage in Early Colorectal Cancer  

PubMed Central

Background/Aims Mini-probe endoscopic ultrasonography (mEUS) is a useful diagnostic tool for accurate assessment of tumor invasion. The aim of this study was to estimate the accuracy of mEUS in patients with early colorectal cancer (ECC). Methods Ninety lesions of ECC underwent mEUS for pre-treatment staging. We divided the lesions into either the mucosal group or the submucosal group according to the mEUS findings. The histological results of the specimens were compared with the mEUS findings. Results The overall accuracy for assessing the depth of tumor invasion (T stage) was 84.4% (76/90). The accuracy of mEUS was significantly lower for submucosal lesions compared to mucosal lesions (p=0.003) and it was lower for large tumors (?2 cm) (p=0.034). The odds ratios of large tumors and submucosal tumors affecting the accuracy of T staging were 3.46 (95% confidence interval [CI], 1.05 to 11.39) and 6.25 (95% CI, 1.85 to 25.14), respectively. When submucosal tumors were combined with large size, the odds ratio was 14.67 (95% CI, 1.46 to 146.96). Conclusions The overall accuracy of T stage determination with mEUS was considerably high in patients with ECC; however, the accuracy decreased when tumor size was >2 cm or the tumor had invaded the submucosal layer. PMID:23560151

Tsung, Pei Chuan; Park, Jong Hyeok; Kim, Sun Young; Park, Won Wo; Kim, Hyun Tae; Kim, Jin Nam; Kang, Yun Kyung; Moon, Jeong Seop

2013-01-01

302

Increased expression of tumor proliferation genes in Hispanic women with early-stage breast cancer.  

PubMed

Hispanic women have higher breast cancer mortality compared to non-Hispanic whites. We evaluated for Proliferation Axis Score differences, as determined by Oncotype Dx, in Hispanic and non-Hispanic white women with newly diagnosed breast cancer. We matched 219 women, based upon age, stage, and nodal status. Compared to non-Hispanic whites, Hispanic women with hormone-sensitive, HER2-negative early-stage breast cancer had a higher Proliferation Axis Score. No differences were seen in Recurrence Score, ER, PR, or HER2 by Oncotype DX. CCNB1 and AURKA were significantly higher in Hispanic women. These tumor differences may help explain breast cancer outcome differences between the two ethnicities. PMID:25254601

Kalinsky, Kevin; Lim, Emerson A; Andreopoulou, Eleni; Desai, Avni M; Jin, Zhezhen; Tu, Yifan; Hibshoosh, Hanina; Wang, Antai; Greenlee, Heather; Crew, Katherine D; Maurer, Matthew; Sparano, Joseph A; Hershman, Dawn L

2014-11-01

303

Early-stage precipitation in Al-Zn-Mg-Cu alloy (7050)  

SciTech Connect

GP zone and metastable {eta}{sup '} formation during the early-stage precipitation of a 7050 Al alloy aged at 121 deg. C has been investigated using transmission electron microscopy, together with 3-dimensional atom probe analysis (of the chemistry and morphology) of individual precipitates. Small Mg-rich clusters (GPI zones) are found in the alloy after short ageing times at 121 deg. C, together with larger GPI zones (Zn/Mg=1.0). Zn-rich {eta}{sup '} platelets are seen to form mainly between 30 and 240 min ageing, coexisting with larger GPI zones. A significant fraction of <1 1 0> elongated clusters have also been observed over this period of ageing. The dominant mechanism for {eta}{sup '} formation at this stage is shown to be by transformation of small GPI zones, via these elongated clusters and not by nucleation on larger zones.

Sha Gang; Cerezo, Alfred

2004-09-06

304

Early life-stage and multigeneration toxicity study with bisphenol A and fathead minnows (Pimephales promelas).  

PubMed

Regulatory guidelines for long term testing to assess the toxicity of xenobiotic compounds such as bisphenol A (BPA) with fish have focused on survival, growth, and development in early life stages. Early life stages are critical windows of exposure, but do not address later phases in the life cycle, such as reproduction, that are equally important for the continued survival of the organisms. Residual amounts of BPA are released to surface water. BPA has, therefore, been the subject of considerable toxicity testing with fish and other aquatic organisms. A long term multigeneration test with fish has been conducted to better interpret the environmental relevance of detectable levels of BPA. Fathead minnow (Pimephales promelas) were exposed for 444 days over the course of three generations that included F0 reproducing adults, F1 eggs grown to be reproducing adults, and F2 eggs. Endpoints included survival, growth, reproduction, and vitellogenin concentrations. Concentrations tested ranged from 1 to 1,280 ?g/L. No observed effect concentrations (NOEC) of 640 ?g/L and higher for growth parameters show few differences between age or generation. Reproductive NOEC in F0 and F1 breeding pairs were 640 and 160 ?g/L, respectively. The lowest NOEC related to survival, growth and development or reproduction was 16 ?g/L for F2 hatching success. This long term study covered both early life and adult reproduction stages that allowed examination of all critical windows of exposure. Overall, NOEC ranging from 16 to 1,280 ?g/L were found, which are well above median and upper 95th percentile concentrations of BPA in fresh waters in North America and Europe (0.081 and 0.47 ?g/L and 0.01 and 0.035 ?g/L, respectively). The likelihood is low that measured concentrations of BPA in surface water would affect fish, even if exposed over more than one generation. PMID:21700340

Staples, Charles A; Tilghman Hall, A; Friederich, Urs; Caspers, Norbert; Klecka, Gary M

2011-09-01

305

Adjuvant vaginal cuff brachytherapy for high-risk, early stage endometrial cancer  

PubMed Central

Purpose To report outcomes following adjuvant high-dose-rate vaginal brachytherapy (VBT) with or without chemotherapy for high-intermediate risk (HIR) and high-risk, early stage endometrial cancer as defined in Gynecologic Oncology Group trial 0249. Material and methods From May 2000 to January 2014, 68 women with HIR and high-risk endometrial cancer underwent surgical staging followed by VBT. Median VBT dose was 21 Gy delivered in three fractions prescribed to 0.5 cm depth. Paclitaxel 175 mg/m2 and carboplatin area under the curve 6 was administered every 21 days in sequence with VBT. Actuarial survival estimates were calculated using the Kaplan-Meier method. Results Patient demographics included a median age of 66 years (range: 36-91) and stages IA (49%), IB (38%), and II (13%), respectively. Thirty-one (46%) patients had HIR disease with endometrioid histology, and 33 (48%) patients had serous or clear cell histology. Thirty-seven (54%) patients received a median 3 cycles (range: 3-6) of chemotherapy in addition to VBT, and 65 patients (96%) completed all prescribed therapy. During a median follow up of 33.1 months (range: 4.0-161.7), four patients have recurred, including one vaginal recurrence. The 3-year estimates of vaginal, pelvic, and distant recurrences were 1.9%, 2.4%, and 9.1%, respectively. The 3-year rates of disease-free and overall survival were 87.7% and 93.9%, respectively. Conclusions Early outcomes with adjuvant VBT with or without chemotherapy demonstrate high rates of vaginal and pelvic control for women with HIR disease. Early vaginal and pelvic relapses in high-risk patients suggest that pelvic external beam radiotherapy is warranted in this subgroup, but additional data from large phase III trials is warranted. PMID:25337127

Eastwick, Gary; Anne, Pramila Rani; Rosenblum, Norman G.; Schilder, Russell J.; Chalian, Raffi; Zibelli, Allison M.; Kim, Christine H.; Den, Robert

2014-01-01

306

Cognitive and Social Processes Predicting Partner Psychological Adaptation to Early Stage Breast Cancer  

PubMed Central

Introduction The diagnosis and subsequent treatment for early stage breast cancer is stressful for partners. Little is known about the role of cognitive and social processes predicting the longitudinal course of partners’ psychosocial adaptation. This study evaluated the role of cognitive and social processing in partner psychological adaptation to early stage breast cancer, evaluating both main and moderator effect models. Moderating effects for meaning-making, acceptance, and positive reappraisal on the predictive association of searching for meaning, emotional processing, and emotional expression on partner psychological distress were examined. Materials and Methods Partners of women diagnosed with early stage breast cancer were evaluated shortly after the ill partner’s diagnosis (n= 253), nine (n = 167), and 18 months (n = 149) later. Partners completed measures of emotional expression, emotional processing, acceptance, meaning-making, and general and cancer-specific distress at all time points. Results Lower satisfaction with partner support predicted greater global distress, and greater use of positive reappraisal was associated with greater distress. The predicted moderator effects for found meaning on the associations between the search for meaning and cancer-specific distress were found and similar moderating effects for positive reappraisal on the associations between emotional expression and global distress and for acceptance on the association between emotional processing and cancer-specific distress were found. Conclusions Results indicate several cognitive-social processes directly predict partner distress. However, moderator effect models in which the effects of partners’ processing depends upon whether these efforts result changes in perceptions of the cancer experience may add to the understanding of partners’ adaptation to cancer. PMID:18435865

Manne, Sharon; Ostroff, Jamie; Fox, Kevin; Grana, Generosa; Winkel, Gary

2009-01-01

307

Depressive Symptoms are Increased in the Early Perimenopausal Stage in Ethnically Diverse HIV+ and HIV? Women  

PubMed Central

Objective The risk of clinically significant depressive symptoms increases during the perimenopause. With highly active antiretroviral treatment (HAART), more HIV-infected women survive to transition through the menopause. In a cross-sectional analysis, we evaluated the association of menopausal stage and vasomotor symptoms with depressive symptoms in an ethnically diverse, cohort of women with a high prevalence of HIV. Methods Participants included 835 HIV-infected women and 335 HIV-uninfected controls from the Women’s Interagency HIV Study (WIHS; 63% African-American). The Center for Epidemiological Studies Depression (CES-D) scale was used to screen for elevated depressive symptoms. Menopausal stages were defined according to standard definitions. Logistic regression analysis was used to identify predictors of elevated depressive symptoms. Results Compared to premenopausal women, early perimenopausal (OR 1.74, 95%CI 1.17–2.60), but not late perimenopausal or postmenopausal women were more likely to show elevated depressive symptoms in adjusted analyses. The odds were similar in HIV-infected and HIV-uninfected women. Persistent vasomotor symptoms also predicted elevated depressive symptoms in HIV-infected and uninfected women (OR 1.45, 95%CI 1.02–2.06). In HIV-infected women, menopausal stage interacted with antiretroviral use (p=0.02); the likelihood of elevated depressive symptoms in early perimenopause compared with premenopause was especially high in HAART-untreated women (OR 3.87, 95%CI 1.57–9.55). Conclusions In HIV+ and HIV? women, the odds of elevated depressive symptoms were significantly higher during the early perimenopause. Elevated depressive symptoms were associated with nonadherence to HAART, underscoring the importance of screening and treating depressive symptoms in HIV+ women who have experienced a change in the regularity of their menstrual cycles. PMID:22872013

Maki, Pauline M.; Rubin, Leah H.; Cohen, Mardge; Golub, Elizabeth T.; Greenblatt, Ruth M.; Young, Mary; Schwartz, Rebecca M.; Anastos, Kathryn; Cook, Judith A.

2012-01-01

308

A Novel Low Dose Fractionation Regimen for Adjuvant Vaginal Brachytherapy in Early Stage Endometrial Cancer  

PubMed Central

Purpose To evaluate local control, survival and toxicity in patients with early-stage endometrioid adenocarcinoma of the uterus treated with adjuvant high-dose-rate (HDR) vaginal brachytherapy (VB) alone using a novel low dose regimen Methods We reviewed records of 414 patients with stage IA to stage II endometrial adenocarcinoma treated with VB alone from 2005 to 2011. Of these, 157 patients with endometrioid histology received 24 Gy in 6 fractions of HDR vaginal cylinder brachytherapy and constitute the study population. Dose was prescribed at the cylinder surface and delivered twice weekly in the post-operative setting. Local control and survival rates were calculated by the Kaplan-Meier method. Results All 157 patients completed the prescribed course of VB. Median follow-up time was 22.8 months (range, 1.5–76.5). Two patients developed vaginal recurrence, one in the periurethral region below the field and one in the fornix after treatment with a 2.5-cm cylinder. Three patients developed regional recurrence in the para-aortic region. Two patients developed distant metastasis (lung and carcinomatosis). The 2-year rate of vaginal control was 98.6%, locoregional control was 97.9% and disease-free survival was 96.8%. The 2-year overall survival rate was 98.7%. No Grade 2 or higher vaginal, gastrointestinal, genitourinary or skin long-term toxicity was reported for any patient. Conclusion Vaginal brachytherapy alone in early-stage endometrial cancer provides excellent results in terms of locoregional control and disease-free survival. The fractionation scheme of 24 Gy in 6 fractions prescribed to the cylinder surface was well-tolerated with minimal late toxicity. PMID:22850411

Townamchai, Kanokpis; Lee, Larissa; Viswanathan, Akila N.

2012-01-01

309

Clinical implication of surgically treated early-stage cervical cancer with multiple high-risk factors  

PubMed Central

Objective Presence of high-risk factor in cervical cancer is known to be associated with decreased survival outcomes. However, the significance of multiple high-risk factors in early-stage cervical cancer related to survival outcomes, recurrence patterns, and treatment implications is not well elucidated. Methods A retrospective study was conducted for surgically treated cervical cancer patients (stage IA2-IIB, n=540). Surgical-pathological risk factors were examined and tumors expressing ?1 high-risk factors (nodal metastasis, parametrial involvement, or positive surgical margin) were eligible for analysis (n=177, 32.8%). Survival analysis was performed based on the number of high-risk factors and the type of adjuvant therapy. Results There were 68 cases (38.4%) expressed multiple high-risk factors (2 high-risk factors: n=58, 32.8%; 3 high-risk factors: n=10, 5.6%). Multiple high-risk factors remained an independent prognosticator for decreased survival outcomes after controlling for age, histology, stage, and treatment type (disease-free survival: hazard ratio [HR], 2.34; p=0.002; overall survival: HR, 2.32; p=0.007). Postoperatively, 101 cases (57.1%) received concurrent chemoradiotherapy (CCRT) and 76 cases (42.9%) received radiotherapy (RT) alone. CCRT was beneficial in single high-risk factor cases: HRs for CCRT over RT alone for cumulative risk of locoregional and distant recurrence, 0.27 (p=0.022) and 0.27 (p=0.005), respectively. However, tumor expressing multiple high-risk factors completely offset the benefit of CCRT over RT alone for the risk of distant recurrence: HR for locoregional and distant recurrence, 0.31 (p=0.071) and 0.99 (p=0.980), respectively. Conclusion Special consideration for the significance of multiple high-risk factors merits further investigation in the management of surgically treated early-stage cervical cancer. PMID:25310856

Mabuchi, Seiji; Okazawa, Mika; Kawano, Mahiru; Kuroda, Hiromasa; Kamiura, Shoji; Kimura, Tadashi

2015-01-01

310

Effect of ocean acidification on early life stages of Atlantic herring (Clupea harengus L.)  

NASA Astrophysics Data System (ADS)

Due to atmospheric accumulation of anthropogenic CO2 the partial pressure of carbon dioxide (pCO2) in surface seawater increases and the pH decreases. This process known as ocean acidification might have severe effects on marine organisms and ecosystems. The present study addresses the effect of ocean acidification on early developmental stages, the most sensitive stages in life history, of the Atlantic herring (Clupea harengus L.). Eggs of the Atlantic herring were fertilized and incubated in artificially acidified seawater (pCO2 1260, 1859, 2626, 2903, 4635 ?atm) and a control treatment (pCO2 480 ?atm) until the main hatch of herring larvae occurred. The development of the embryos was monitored daily and newly hatched larvae were sampled to analyze their morphometrics, and their condition by measuring the RNA/DNA ratios. Elevated pCO2 neither affected the embryogenesis nor the hatch rate. Furthermore the results showed no linear relationship between pCO2 and total length, dry weight, yolk sac area and otolith area of the newly hatched larvae. For pCO2 and RNA/DNA ratio, however, a significant negative linear relationship was found. The RNA concentration at hatching was reduced at higher pCO2 levels, which could lead to a decreased protein biosynthesis. The results indicate that an increased pCO2 can affect the metabolism of herring embryos negatively. Accordingly, further somatic growth of the larvae could be reduced. This can have consequences for the larval fish, since smaller and slow growing individuals have a lower survival potential due to lower feeding success and increased predation mortality. The regulatory mechanisms necessary to compensate for effects of hypercapnia could therefore lead to lower larval survival. Since the recruitment of fish seems to be determined during the early life stages, future research on the factors influencing these stages are of great importance in fisheries science.

Franke, A.; Clemmesen, C.

2011-12-01

311

Effect of ocean acidification on early life stages of Atlantic herring (Clupea harengus L.)  

NASA Astrophysics Data System (ADS)

Due to atmospheric accumulation of anthropogenic CO2 the partial pressure of carbon dioxide (pCO2 in surface seawater increases and the pH decreases. This process known as ocean acidification might have severe effects on marine organisms and ecosystems. The present study addresses the effect of ocean acidification on the early developmental stages, the most sensitive stages in the life history, of the Atlantic herring (Clupea harengus L.). Eggs of the Atlantic herring were fertilized and incubated in artificially acidified seawater (pCO2 1260, 1859, 2626, 2903, 4635 ?atm) and a control treatment (pCO2 480 ?atm) until the main hatch of herring larvae occurred. The development of the embryos was monitored daily and newly hatched larvae were sampled to analyze their morphometrics, and their condition by measuring the RNA/DNA ratios. Elevated pCO2 neither affected the embryogenesis nor the hatch rate. Furthermore the results showed no linear relationship between pCO2 and total length, dry weight, yolk sac area and otolith area of the newly hatched larvae. For pCO2 and RNA/DNA ratio, however, a significant negative linear relationship was found. The RNA concentration at hatching was reduced at higher pCO2 levels, which consequently should lead to a decreased protein biosynthesis. The results indicate that an increased pCO2 can affect the metabolism of herring embryos negatively. Accordingly, further somatic growth of the larvae could be reduced. This can have consequences for the larval fish, since smaller and slow growing individuals have a lower survival potential due to lower feeding success and increased predation mortality. The regulatory mechanisms necessary to compensate for effects of hypercapnia could therefore lead to lower larval survival and could affect the ecosystem and fisheries. Since the recruitment of fish seems to be determined during the early life stages, future research on the factors influencing these stages are of great importance in fisheries science.

Franke, A.; Clemmesen, C.

2011-07-01

312

Early stage formation of graphene on the C face of 6H-SiC  

NASA Astrophysics Data System (ADS)

An investigation of the early stage formation of graphene on the C face of 6H-silicon carbide (SiC) is presented. We show that the sublimation of few atomic layers of Si out of the SiC substrate is not homogeneous. In good agreement with the results of theoretical calculations it starts from defective sites, mainly dislocations that define nearly circular graphene layers, which have a pyramidal, volcanolike shape with a center chimney where the original defect was located. At higher temperatures, complete conversion occurs but, again, it is not homogeneous. Within the sample surface, the intensity of the Raman bands evidences inhomogeneous thickness.

Camara, N.; Rius, G.; Huntzinger, J.-R.; Tiberj, A.; Magaud, L.; Mestres, N.; Godignon, P.; Camassel, J.

2008-12-01

313

Nanoscale duplex oxide growth during early stages of oxidation of Cu-Ni(100)  

SciTech Connect

A combination of real-time in situ synchrotron x-ray diffraction and ex situ transmission electron microscopy is utilized to investigate the early stages of oxidation of Cu-Ni(100). Sequential formation of NiO and Cu{sub 2}O oxides was observed by increasing oxygen partial pressure, and the Cu{sub 2}O phase was identified to form preferentially on top of NiO nanoislands. The origin of this unexpected phenomenon is attributed to localized enrichment of Cu atoms accompanied with NiO growth, which thermodynamically drives the nanoscale Cu{sub 2}O/NiO duplex oxide growth.

Zhou Guangwen [Department of Mechanical Engineering and Multidisciplinary Program in Materials Science and Engineering, State University of New York, Binghamton, New York 13902 (United States); Fong, Dillon D.; Fuoss, Paul H.; Baldo, Peter M.; Thompson, Loren J.; Eastman, Jeffrey A. [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Wang Liang [Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)

2009-10-01

314

Clean Energy Finance: Challenges and Opportunities of Early-Stage Energy Investing (Presentation)  

SciTech Connect

Characterized by a changing landscape and new opportunities, today's increasingly complex energy decision space will need innovative financing and investment models to appropriately assess risk and profitability. This report provides an overview of the current state of clean energy finance across the entire spectrum but with a focus on early stage investing, and it includes insights from investors across all investment classes. Further, this report aims to provide a roadmap with the mechanisms, limitations, and considerations involved in making successful investments by identifying risks, challenges, and opportunities in the clean energy sector.

Heap, D.; Pless, J.; Aieta, N.

2013-12-01

315

The Evolving Role of Radiotherapy in Early Stage Hodgkin’s Lymphoma  

PubMed Central

Radiation therapy has a key role in the combined modality treatment of early-stage Hodgkin’s Lymphoma (HL). Nevertheless, late toxicity still remains an issue. A modern approach in HL radiotherapy includes lower doses and smaller fields, together with the implementation of sophisticated and dedicated delivery techniques. Aim of the present review is to discuss the current role of radiotherapy and its potential future developments, with a focus on major clinical trials, technological advances and their repercussion in the clinical management of HL patients. PMID:24959332

Ricardi, Umberto; Filippi, Andrea Riccardo; Piva, Cristina; Franco, Pierfrancesco

2014-01-01

316

Selective attention to signs of success: social dominance and early stage interpersonal perception.  

PubMed

Results from two experiments suggest that observers selectively attend to male, but not female, targets displaying signs of social dominance. Participants overestimated the frequency of dominant men in rapidly presented stimulus arrays (Study 1) and visually fixated on dominant men in an eyetracking experiment (Study 2). When viewing female targets, participants attended to signs of physical attractiveness rather than social dominance. Findings fit with evolutionary models of mating, which imply that dominance and physical attractiveness sometimes tend to be prioritized preferentially in judgments of men versus women, respectively. Findings suggest that sex differences in human mating are observed not only at the level of overt mating preferences and choices but also at early stages of interpersonal perception. This research demonstrates the utility of examining early-in-the-stream social cognition through the functionalist lens of adaptive thinking. PMID:18192434

Maner, Jon K; DeWall, C Nathan; Gailliot, Matthew T

2008-04-01

317

Investigating the Early Stages of Person Perception: The Asymmetry of Social Categorization by Sex vs. Age  

PubMed Central

Early perceptual operations are central components of the dynamics of social categorization. The wealth of information provided by facial cues presents challenges to our understanding of these early stages of person perception. The current study aimed to uncover the dynamics of processing multiply categorizable faces, notably as a function of their gender and age. Using a modified four-choice version of a mouse-tracking paradigm (which assesses the relative dominance of two categorical dimensions), the relative influence that sex and age have on each other during categorization of infant, younger adult, and older adult faces was investigated. Results of these experiments demonstrate that when sex and age dimensions are simultaneously categorized, only for infant faces does age influence sex categorization. In contrast, the sex of both young and older adults was shown to influence age categorization. The functional implications of these findings are discussed in light of previous person perception research. PMID:24465423

Cloutier, Jasmin; Freeman, Jonathan B.; Ambady, Nalini

2014-01-01

318

Comparing Soft Computing Techniques For Early Stage Software Development Effort Estimations  

E-print Network

Accurately estimating the software size, cost, effort and schedule is probably the biggest challenge facing software developers today. It has major implications for the management of software development because both the overestimates and underestimates have direct impact for causing damage to software companies. Lot of models have been proposed over the years by various researchers for carrying out effort estimations. Also some of the studies for early stage effort estimations suggest the importance of early estimations. New paradigms offer alternatives to estimate the software development effort, in particular the Computational Intelligence (CI) that exploits mechanisms of interaction between humans and processes domain knowledge with the intention of building intelligent systems (IS). Among IS, Artificial Neural Network and Fuzzy Logic are the two most popular soft computing techniques for software development effort estimation. In this paper neural network models and Mamdani FIS model have been used to pr...

Bhatnagar, Roheet

2012-01-01

319

Adventitial fibroblasts are activated in the early stages of atherosclerosis in the apolipoprotein E knockout mouse  

SciTech Connect

The role of the adventitia in vascular function and vascular lesion formation has been largely ignored. This study observed the activation of the adventitia and specifically the fibroblasts in the development of atherosclerosis in the apoE(-/-) mouse. The results showed a gradual increase in expression of collagen types I and III after 2, 4, and 8 weeks of hyperlipidic diet. The earliest expression of monocyte chemoattractant protein-1 (MCP-1) protein and mRNA was detected in the adventitial fibroblast before the formation of intimal lesions. Proliferation, too, was first found in the adventitial fibroblasts. We hypothesize that the adventitial fibroblast is activated in the early stage of atherosclerosis. Adventitial inflammation may be an early event in the development of atherosclerotic lesions.

Xu Fang [Department of Pathophysiology, School of Medicine, Shandong University, Jinan 250012, Shandong (China); Ji Jian [Department of Pathophysiology, School of Medicine, Shandong University, Jinan 250012, Shandong (China); Li Li [Department of Pathophysiology, School of Medicine, Shandong University, Jinan 250012, Shandong (China); Chen Rong [Department of Pathophysiology, School of Medicine, Shandong University, Jinan 250012, Shandong (China); Hu Weicheng [Department of Pathophysiology, School of Medicine, Shandong University, Jinan 250012, Shandong (China)]. E-mail: huweicheng@sdu.edu.cn

2007-01-19

320

Effects of water level, shade and time on germination and growth of freshwater marsh plants along a simulated successional gradient  

USGS Publications Warehouse

1. We examined the effect of soil organic content (1.4, 3.6, 7.2% soil C), water level (+2, -1, -4 cm from soil surface) and duration (13 or 33 days) on 10 species that varied in abundance during succession in freshwater marshes. We also determined the effect of shade (0, 40, 80% shade) and soil organic content (1.4 and 7.2% soil C) on germination of six species over 62 days with water 0.5 cm below the soil surface. 2. Water level consistently affected species germination on both dates. Above-ground biomass was generally higher with increasing organic content of soil, but shade had little effect on germination or height. 3 The hydrologic zone in which species were found in the field was a good indicator of the response of germination to hydrology. Both early successional species and species wide-spread across the successional gradient show similar germination on all organic contents, while later successional species appear to germinate best at higher organic contents. 4. Successional changes in soils are capable of affecting plant community development, independent of disturbance.

Kellogg, C.H.; Bridgham, S.D.; Leicht, S.A.

2003-01-01

321

Impact of [{sup 18}F] Fluorodeoxyglucose Positron Emission Tomography on Staging and Management of Early-Stage Follicular Non-Hodgkin Lymphoma  

SciTech Connect

Purpose: Accurate staging is critical to select patients with early-stage (I-II) follicular lymphoma (ESFL) suitable for involved-field radiotherapy (IFRT) and to define the radiotherapy portal. We evaluated the impact of fluorodeoxyglucose (FDG) PET on staging, treatment, and outcome for patients with ESFL on conventional staging. Methods and Materials: Forty-two patients with untreated ESFL (World Health Organization Grade I-IIIa, or 'low grade') following a minimum of physical examination, computerized tomography, and bone marrow examination (conventional assessment) and who had staging PET from June 1997 to June 2006 were studied retrospectively. Stage allocation was based on routine imaging reports. Disease sites, stage, and management plan were recorded based on conventional assessment or conventional assessment plus PET. Results: FDG avidity was demonstrated in 97% of patients in whom disease was evident on conventional assessment after biopsy. PET findings suggested a change of stage or management in 19 patients: 13 (31%) who were upstaged to Stage III-IV, altering ideal management from IFRT to systemic therapy, and 6 (14%) who had the involved field enlarged, including 4 upstaged from Stage I to II. Of these 19 cases, PET findings were considered true positive in 8 patients, indeterminate in 10, and false positive in only 1 patient. Conclusions: Our data confirm that ESFL is usually FDG-avid. In routine practice, PET has the potential to upstage and thereby alter management in a high proportion of patients with apparent ESFL.

Wirth, Andrew [Department of Radiation Oncology, Peter MacCallum Cancer Centre, Melbourne (Australia)], E-mail: andrew.wirth@petermac.org; Foo, Marcus [Department of Radiation Oncology, Peter MacCallum Cancer Centre, Melbourne (Australia); Seymour, John F. [Department of Hematology, Peter MacCallum Cancer Centre, Melbourne (Australia); Department of Medicine, University of Melbourne, Melbourne (Australia); MacManus, Michael P. [Department of Radiation Oncology, Peter MacCallum Cancer Centre, Melbourne (Australia); Hicks, Rodney J. [Department of Metabolic Imaging, Peter MacCallum Cancer Centre, Melbourne (Australia)

2008-05-01

322

Intact relational memory and normal hippocampal structure in the early stage of psychosis  

PubMed Central

Background Previous studies indicate the transition to psychosis is associated with dynamic changes of hippocampal integrity. Here we explored hippocampal volume and neural activation during a relational memory task in patients who were in the early stage of a psychotic illness. Methods 41 early psychosis patients and 34 healthy controls completed a transitive inference (TI) task used previously in chronic schizophrenia patients. Participants learned to select the “winner” of two sets of stimulus pairs drawn from an overlapping sequence (A>B>C>D>E) and a non-overlapping set (a>b, c>d, e>f, g>h). During an fMRI scan, participants were tested on the trained pairs and made inferential judgments on novel pairings that could be solved based on training (e.g. B vs. D). Hippocampal volumes were manually segmented and compared between groups. fMRI analyses included 27 early psychosis patients and 30 controls who met memory training criteria. Results Groups did not differ on inference performance or hippocampal volume, and exhibited similar activation of medial temporal regions when judging non-overlapping pairs. However, patients who failed to meet memory training criteria had smaller hippocampal volumes. Neural activity during TI was less widespread in early psychosis patients but between-group differences were not significant. Hippocampal activity during TI was positively correlated with inference performance only in control subjects. Conclusions Our results provide evidence that relational memory impairment and hippocampal abnormalities, well established in chronic schizophrenia, are not fully present in early psychosis patients. This provides a rationale for early intervention, targeting the possible delay, reduction, or prevention of these deficits. PMID:22055016

Williams, Lisa E.; Avery, Suzanne N.; Woolard, Austin A.; Heckers, Stephan

2012-01-01

323

The relationship between cortisol and verbal memory in the early stages of Huntington's disease.  

PubMed

Hypothalamic pituitary adrenal (HPA) axis hyperactivity has been linked to learning and memory difficulties in a range of neurodegenerative and neuropsychiatric conditions. In Huntington's disease (HD), both declines in learning and memory and HPA axis dysfunction are present early in the disease. However, the relationship between specific learning and memory deficits and HPA axis functioning in HD has not been examined. The aim of this study was to investigate cortisol levels in relation to verbal learning and memory in pre-diagnosed (pre-HD) participants and patients at the early stages of diagnosed HD (early-HD). Cortisol concentration was assayed in saliva samples from 57 participants (17 early-HD, 20 pre-HD, and 20 controls) at four time-points across a 24-h period. Verbal memory was assessed using the California Verbal Learning Test-Second Edition (CVLT-II). We focused statistical analyses on the late evening cortisol concentration, and examined cortisol levels and verbal memory function in relation to diagnostic group (control, pre-HD, early-HD), and in a separate set of analyses combining pre-HD and early-HD (and excluding controls) we also examined cortisol and verbal memory performance in relation to the severity of HD-related motor signs. Of these two classification approaches, HD motor sign severity was more strongly associated with high evening cortisol levels and both reduced information encoding and memory retrieval. Separately, there was also a trend of higher cortisol levels in pre-HD. The findings suggest hypercortisolism and the underlying pathological changes may begin many years before a clinical diagnosis is made, but the memory decline associated with HPA axis disturbance may only become detectable once motor signs become pronounced. PMID:23180175

Shirbin, Christopher A; Chua, Phyllis; Churchyard, Andrew; Hannan, Anthony J; Lowndes, Georgia; Stout, Julie C

2013-03-01

324

EFFECTS OF DIET QUANTITY ON SHEEPSHEAD MINNOWS 'CYPRINODON VARIEGATUS' DURING EARLY LIFE-STAGE EXPOSURES TO CHLORPYRIFOS  

EPA Science Inventory

The influence of food quantity on the effects of chlorpyrifos was determined in six early life-stage (ELS) toxicity tests with estuarine sheepshead minnows, Cyprinodon variegatus. Three ELS tests were conducted simultaneously, each with a different feeding density: approximately ...

325

The Problems of Replication in the Early Stages of Evolution: Enumeration of Variants and Spatial Configurations of Replicators  

NASA Astrophysics Data System (ADS)

Two main problems of replication in the early stages of evolution are discussed: the problem of exponentially large number of conformational degrees of freedom and the problem of enumeration of variants.

Melkikh, Alexey V.

2015-01-01

326

Abstract---Early stage Parkinson's disease is characterized by facial masking that reduces the ability for a caregiver to  

E-print Network

Abstract--- Early stage Parkinson's disease is characterized by facial masking that reduces to drive the relationship towards acceptable social and medical treatment norms. I. INTRODUCTION One domain an appropriate treatment regime (compliance) or is disinterested in the treatment process leading

327

Abstract--Early stage Parkinson's disease is characterized by facial masking that reduces the ability for a caregiver to  

E-print Network

Abstract-- Early stage Parkinson's disease is characterized by facial masking that reduces to drive the relationship towards acceptable social and medical treatment norms. I. INTRODUCTION One domain an appropriate treatment regime (compliance) or is disinterested in the treatment process leading

328

Impact of the CE mark approval on exit opportunities and validation for early stage medical device companies  

E-print Network

The aim of this thesis was to look at the impact of acquiring the CE marking approval on the outcome of early stage medical device companies, specifically its impact on strategic acquisition opportunities and on valuation. ...

Kothari, Ashish (Ashish Shrikant)

2011-01-01

329

Targeted labeling of an early-stage tumor spheroid in a chorioallantoic membrane model with upconversion nanoparticles  

NASA Astrophysics Data System (ADS)

In vivo detection of cancer at an early-stage, i.e. smaller than 2 mm, is a challenge in biomedicine. In this work target labeling of an early-stage tumor spheroid (~500 ?m) is realized for the first time in a chick embryo chorioallantoic membrane (CAM) model with monoclonal antibody functionalized upconversion nanoparticles (UCNPs-mAb).In vivo detection of cancer at an early-stage, i.e. smaller than 2 mm, is a challenge in biomedicine. In this work target labeling of an early-stage tumor spheroid (~500 ?m) is realized for the first time in a chick embryo chorioallantoic membrane (CAM) model with monoclonal antibody functionalized upconversion nanoparticles (UCNPs-mAb). Electronic supplementary information (ESI) available: Details of experimental procedures for the sample preparation and characterization, Chick CAM model, 3-D multicellular tumor spheroids, UCNPs circulating in CAM. See DOI: 10.1039/c4nr05638h

Liu, Kai; Holz, Jasmin A.; Ding, Yadan; Liu, Xiaomin; Zhang, Youlin; Tu, Langping; Kong, Xianggui; Priem, Bram; Nadort, Annemarie; Lambrechts, Saskia A. G.; Aalders, Maurice C. G.; Buma, Wybren Jan; Liu, Yichun; Zhang, Hong

2015-01-01

330

Mayo and NCI researchers find that trastuzumab continues to show life for HER2-positve early stage breast cancer  

Cancer.gov

After following breast cancer patients for an average of eight-plus years, researchers say that adding trastuzumab (Herceptin) to chemotherapy significantly improved the overall and disease-free survival of women with early stage HER2-positive breast cancer.

331

Efficacy of adjuvant CYVADIC chemotherapy in early-stage uterine sarcomas: results of long-term follow-up  

Microsoft Academic Search

Odunsi K, Moneke V, Tammela J, Ghamande S, Seago P, Driscoll D, Marchetti D, Baker T, Lele S. Efficacy of adjuvant CYVADIC chemotherapy in early-stage uterine sarcomas: results of long-term follow-up. Int J Gynecol Cancer 2004;14:659—664. Data on adjuvant chemotherapy in early-stage uterine sarcomas are conflicting and most often based on small patient groups with relatively short duration of follow-up.

K. Odunsi; V. Moneke; J. Tammela; S. Ghamande; P. Seago; D. Driscoll; D. Marchetti; T. Baker; S. Lele

2004-01-01

332

Relative contribution of seed phosphorus reserves and exogenous phosphorus uptake to maize ( Zea mays L.) nutrition during early growth stages  

Microsoft Academic Search

Adequate phosphorus (P) nutrition during early stages is critical for maize growth. Our objective was to evaluate the relative\\u000a contribution of seed P reserves and exogenous P to maize nutrition during early growth stages. Seedlings were grown with labeled\\u000a nutrient solution (32P). Seedlings were harvested periodically over the course of the three-week study. Initially, 87% and 77% of the total

Muhammad Nadeem; Alain Mollier; Christian Morel; Alain Vives; Loïc Prud’homme; Sylvain Pellerin

333

Homogeneity-based feature extraction for classification of early-stage alzheimer's disease from functional magnetic resonance images  

Microsoft Academic Search

Alzheimer's disease is the most common form of age-related dementia. Early-stage diagnosis of Alzheimer is of major importance for the following reasons: Also easily curable conditions like depression, poor nutrition and drug side effects may cause symptoms like early-stage Alzheimer. Moreover, recently some medications have been developed which successfully attenuate the symptoms and delay the progression of Alzheimer, but to

Claudia Plant; Christian Sorg; Valentin Riedl; Afra Wohlschläger

2011-01-01

334

MD Anderson study finds majority of older, early-stage breast cancer patients benefit from radiation after lumpectomy  

Cancer.gov

For the majority of older, early-stage breast cancer patients, radiation therapy following breast conserving surgery may help prevent the need for a later mastectomy, according to research from The University of Texas MD Anderson Cancer Center. The findings, published in the journal Cancer, are contrary to current national treatment guidelines, which recommend that older women with early stage, estrogen-positive disease be treated with lumpectomy followed by estrogen blocker therapy alone -- and forgo radiation therapy post-surgery.

335

Changes in sexual problems over time in women with and without early-stage breast cancer  

PubMed Central

Objectives We aimed to evaluate whether age-matched women with and without early-stage breast cancer differentially experience sexual problems over time and whether changes in patients’ problems differ by surgery type. Methods We conducted four interviews (4–6 weeks, 6 months, 1 year and 2 years) after surgery (patients) or a negative/benign screening mammogram (controls). Mixed-effects models with repeated ordinal measurements tested effects of time and diagnostic group (stages 0, I, IIA vs. controls) and, for patients, effects of time and type of surgery (mastectomy vs. lumpectomy), on a newly developed 9-item sexual-problems measure. Two-sided P-values < 0.05 were considered significant. Results Using data from 1033 women (17.3% stage 0, 33.4% stage I/IIA, 49.3% controls; mean age 57.1; 23.1% non-white; 64.7% married), two factors measuring problems with sexual attractiveness and sexual interest/enjoyment emerged in exploratory factor analysis (alpha ? .74 for each subscale and the 9-item measure). Patients and controls reported few sexual problems on average, but compared with baseline, controls were more likely to report sexual problems on the 9-item measure over time, and stage I patients were less likely to report problems with sexual attractiveness over time (each P < 0.05). Patients with mastectomy (35.7%) were 2.7 times more likely to report sexual problems on the 9-item measure at 2-year follow-up compared with baseline (P = 0.0339). Conclusions Patients and controls experienced few sexual problems over time and, in fact, controls were more likely to report sexual problems at subsequent interviews, whereas patients did not. PMID:20461020

Pérez, Maria; Liu, Ying; Schootman, Mario; Aft, Rebecca L.; Schechtman, Kenneth B.; Gillanders, William E.; Jeffe, Donna B.

2010-01-01

336

Effects of Phosphorus and Nitrogen on Nodulation are Seen Already at the Stage of Early Cortical Cell Divisions in Alnus incana  

Microsoft Academic Search

Background and Aims The present work aimed to study early stages of nodulation in a chronological sequence and to study phosphorus and nitrogen effects on early stages of nodulation in Alnus incana infected by Frankia .A method was developed to quantify early nodulation stages in intact root systems in the root hair-infected actinorhizal plant A. incana. Plant tissue responses were

FRANCESCO GENTILI; LUIS G. WALL; KERSTIN HUSS-DANELL

2006-01-01

337

The Chromosomes of Turkey Embryos during Early Stages of Parthenogenetic Development  

PubMed Central

In the early stages of parthenogenetic development in turkey eggs, many blastoderms are mosaics of haploid, diploid and polyploid cells. The genome composition of these blastoderms can be identified by C-banding. They may be generally described as either A-Z/2A-ZZ/nA-nZ or A-W/2A-WW/nA-nW and are found in a nearly 1:1 ratio. The blastoderms showing the W body (W+) become lethal within two days of incubation. The haploid cell proportion decreases rapidly during the early stage of development, and, as haploid cells decrease, the proportion of polyploid cells appears to increase. At six days of incubation, various kinds of parthenogenetic development can be observed. Their genome compositions are either diploid (2A-ZZ) or mosaic (A-Z/2A-ZZ). These findings suggest that diploid parthenogenesis occurs by either suppression of meiosis II or chromosome doubling some time after the first cleavage division. The frequent occurrence of mosaic blastoderms indicates that the majority, if not all, of the parthenogenetic embryos initiate their development in haploid ova. PMID:7327389

Harada, Ko; Buss, Edward G.

1981-01-01

338

Effects of Marine Toxins on the Reproduction and Early Stages Development of Aquatic Organisms  

PubMed Central

Marine organisms, and specially phytoplankton species, are able to produce a diverse array of toxic compounds that are not yet fully understood in terms of their main targets and biological function. Toxins such as saxitoxins, tetrodotoxin, palytoxin, nodularin, okadaic acid, domoic acid, may be produced in large amounts by dinoflagellates, cyanobacteria, bacteria and diatoms and accumulate in vectors that transfer the toxin along food chains. These may affect top predator organisms, including human populations, leading in some cases to death. Nevertheless, these toxins may also affect the reproduction of aquatic organisms that may be in contact with the toxins, either by decreasing the amount or quality of gametes or by affecting embryonic development. Adults of some species may be insensitive to toxins but early stages are more prone to intoxication because they lack effective enzymatic systems to detoxify the toxins and are more exposed to the toxins due to a higher metabolic growth rate. In this paper we review the current knowledge on the effects of some of the most common marine toxins on the reproduction and development of early stages of some organisms. PMID:20161971

Vasconcelos, Vítor; Azevedo, Joana; Silva, Marisa; Ramos, Vítor

2010-01-01

339

Molecular Mechanism of the Early Stage of Amyloidogenic Hexapeptides (NFGAIL) Aggregation  

NASA Astrophysics Data System (ADS)

Peptides/proteins aggregation can give rise to pathological conditions of many human diseases. Small partially ordered oligomers formed in the early stage of aggregation, rather than mature fibrils, are thought to be the main toxicity agent for the living cell. Thus, understanding the pathway and the underlying physical mechanism in the early stage of aggregation is very important for prevention and treatment of these protein functional diseases. Herein we use all-atom molecular dynamics simulations to study the aggregation of four NFGAIL hexapeptides (NFGAIL peptide is a core segment of human islet amyloid polypeptide and exhibits similar aggregation kinetics as the full-length polypeptide). We observe that the peptide monomers in water mainly adopt non-structural coil configurations; the four peptides which are randomly placed in water aggregate spontaneously to partially ordered oligomer (?-sheets) through dimerization or trimerization, with the dimerization predominated. Both parallel and anti-parallel ?-sheets are observed. The hydrophobic interactions drive the initial peptides associations, and the subsequent conformational fluctuations promote the formation of more hydrogen bonds between the dangling hydrogen sites in the main chains of peptides.

Shi, Bi-Yun; Zhou, Bo; Cai, Zhuo-Wei; Xiu, Peng; Yang, Zai-Xing

2013-10-01

340

Behavior of homologous chromosomes in early meiotic stages of human spermatocytes as revealed by FISH  

SciTech Connect

The process by which homologous chromosomes recognize each other at the beginning of meiosis, prior to synapsis, is poorly understood. To gain a better understanding as to when, where and how a given chromosome approaches its pairing partner, chromosome behavior at early stages of meiosis in human spermatocytes was studied. Using multi-color FISH with centromeric- and telomeric-specific probes, as well as with whole chromosome DNA libraries, it was clearly aligned. Rather, similarly to non-homologous chromosomes, they were well separated from each other. At the commencement of synapsis, during the process of homology search, homologues underwent a drastic conformational change, elongating into strands that approached each other by their telomeres. Just preceding the co-alignment of the homologous centromeres, telomeres changed their interphase random distribution and occupied a confined region of the nuclear periphery. Following synapsis, telomeres spread over the whole nuclear periphery. These dynamics in the telomeres distribution, which are unique to early stages of meiosis, are presumably related to the role that telomeres play in the process of homology search and the commencement of synapsis.

Bar-Am, I.; Avivi, L. [Tel-Aviv Univ. (Israel); Mukame, E. [Hasharon Hospital, Petah-Tikva (Israel)

1994-09-01

341

Curcumin Inhibits Mitochondrial Injury and Apoptosis from the Early Stage in EAE Mice  

PubMed Central

The exact pathophysiological change concerning mitochondrial injury and oligodendrocyte apoptosis in MS and EAE model is still unknown. Whether curcumin is able to inhibit mitochondrial injury and suppress the apoptosis in the early stages of MS/EAE is still unclear. We first explored mitochondrial injury and apoptosis at different time points p.i. in C57 BL/6 EAE mice. We then explored the effects of curcumin on mitochondria and apoptosis. Results showed that mitochondrial injury can be observed 3 days p.i. Apoptosis in the spinal cord occurred 3 days p.i. and the apoptotic cells were shown to be oligodendrocytes and neuronal cells. Curcumin significantly reduced the number of apoptotic cells and inhibited the upregulation of cyt-c, caspase-9, and caspase-3 at 7 days p.i. in the EAE mice. These observations demonstrate that mitochondrial injury and oligodendrocyte/neuronal apoptosis occur in the early stages of EAE. Curcumin can inhibit apoptosis in EAE mice which maybe act through protection of mitochondrial injury and inhibition of the intrinsic apoptotic pathway. PMID:24868317

Feng, Jinzhou; Tao, Tao; Yan, Weiping; Chen, Cindy Si; Qin, Xinyue

2014-01-01

342

Alteration of Podocyte Protein Expression and Localization in the Early Stage of Various Hemodynamic Conditions  

PubMed Central

Given that podocalyxin (PCX) and nestin play important roles in podocyte morphogenesis and the maintenance of structural integrity, we examined whether the expression and localization of these two podocyte proteins were influenced in the early stage of various hemodynamic conditions. Mice kidney tissues were prepared by in vivo cryotechnique (IVCT). The distribution of glomeruli and podocyte proteins was visualized with DAB staining, confocal laser scanning microscopy and immunoelectron microscopy. The mRNA levels were examined by real-time quantitative PCR. The results showed the following: Under the normal condition, PCX stained intensely along glomerular epithelial cells, whereas nestin was clearly staining in the endothelial cells and appeared only weakly in the podocytes. Under the acute hypertensive and cardiac arrest conditions, PCX and nestin staining was not clear, with a disarranged distribution, but the colocalization of PCX and nestin was apparent under this condition. In addition, under the acute hypertensive and cardiac arrest conditions, the mRNA levels of PCX and nestin were significantly decreased. Collectively, the abnormal redistribution and decreased mRNA expressions of PCX and nestin are important molecular events at the early stage of podocyte injury during hemodynamic disorders. IVCT may have more advantages for morphological analysis when researching renal diseases. PMID:23502465

Li, Kai; Wang, Juan; Yin, Xiaohui; Zhai, Xiaoyue; Li, Zilong

2013-01-01

343

Towards non-invasive diagnostic imaging of early-stage Alzheimer's disease  

NASA Astrophysics Data System (ADS)

One way to image the molecular pathology in Alzheimer's disease is by positron emission tomography using probes that target amyloid fibrils. However, these fibrils are not closely linked to the development of the disease. It is now thought that early-stage biomarkers that instigate memory loss are composed of A? oligomers. Here, we report a sensitive molecular magnetic resonance imaging contrast probe that is specific for A? oligomers. We attach oligomer-specific antibodies onto magnetic nanostructures and show that the complex is stable and binds to A? oligomers on cells and brain tissues to give a magnetic resonance imaging signal. When intranasally administered to an Alzheimer's disease mouse model, the probe readily reached hippocampal A? oligomers. In isolated samples of human brain tissue, we observed a magnetic resonance imaging signal that distinguished Alzheimer's disease from controls. Such nanostructures that target neurotoxic A? oligomers are potentially useful for evaluating the efficacy of new drugs and ultimately for early-stage Alzheimer's disease diagnosis and disease management.

Viola, Kirsten L.; Sbarboro, James; Sureka, Ruchi; de, Mrinmoy; Bicca, Maíra A.; Wang, Jane; Vasavada, Shaleen; Satpathy, Sreyesh; Wu, Summer; Joshi, Hrushikesh; Velasco, Pauline T.; Macrenaris, Keith; Waters, E. Alex; Lu, Chang; Phan, Joseph; Lacor, Pascale; Prasad, Pottumarthi; Dravid, Vinayak P.; Klein, William L.

2015-01-01

344

Dedifferentiation and aberrations of the endolysosomal compartment characterize the early stage of nephropathic cystinosis.  

PubMed

Nephropathic cystinosis, a lysosomal storage disease caused by mutations in the CTNS gene encoding the lysosomal cystine transporter cystinosin, is characterized by generalized proximal tubule (PT) dysfunction that progresses, if untreated, to end-stage renal disease. The pathogenesis of defective PT cellular transport in nephropathic cystinosis remains unclear. We characterized a recently generated line of C57BL/6 Ctns mice and analyzed endocytic uptake, lysosome function, and dedifferentiation and proliferation markers using primary cultures of PT epithelial cells derived from Ctns(-/-) and Ctns(+/+) littermates. Metabolic studies revealed that Ctns(-/-) mice show a progressive PT dysfunction characterized by low-molecular-weight (LMW) proteinuria, glucosuria and phosphaturia, before structural damage and in the absence of renal failure. These changes are related to decreased expression of the multi-ligand receptors megalin and cubilin and to increased dedifferentiation (ZONAB transcription factor) and proliferation (PCNA and Cyclin D1) rates. Studies on PT cells derived from Ctns(-/-) kidneys confirmed cystine overload, with accumulation of enlarged, dysfunctional lysosomes and reduced expression of endocytic receptors reflected by decreased uptake of specific ligands. These changes were related to a loss of integrity of tight junctions with a nuclear translocation of ZONAB and increased proliferation, as observed in Ctns(-/-) kidneys. These data reveal that the absence of cystinosin in PT cells triggers aberrations of the endolysosomal compartment, transport defects and an abnormal transcription program in the early stage of nephropathic cystinosis. Insights into the early manifestations of cystinosis may offer new targets for intervention, before irreversible renal damage. PMID:24319100

Raggi, Claudia; Luciani, Alessandro; Nevo, Nathalie; Antignac, Corinne; Terryn, Sara; Devuyst, Olivier

2014-05-01

345

Efficacy of low-dose ultraviolet a-1 phototherapy for parapsoriasis/early-stage mycosis fungoides.  

PubMed

Mycosis fungoides (MF) and parapsoriasis (PP) are major dermatologic conditions for which phototherapy continues to be a successful and valuable treatment option. UVA-1 phototherapy is effective in the management of cutaneous T-cell mediated diseases. The aim of the study was to evaluate the efficacy and safety of low-dose UVA-1 phototherapy for the management of PP/early-stage MF. A total of 30 patients, diagnosed with MF (n:19) or PP (n:11) were enrolled to the study. All patients were managed with low-dose UVA-1 (20 or 30 J cm(-2)). Response was assessed clinically and immunohistochemically. UVA-1 treatment led to clinical and histological complete remission (CR) in 11 of 19 MF patients (57.9%), partial remission (PR) in three of 19 (15.8%), after a mean cumulative dose of 1665 (range, 860-3120) J cm(-2) and mean number of 73 exposure (range, 43-107) sessions. Five patients with PP (45.5%) showed CR, and PR was observed in six patients with PP (54.5%) after a mean cumulative dose of 1723 (range, 1060-3030) J cm(-2) and mean number of 74 exposure (range, 53-101) sessions. We conclude that low-dose UVA-1 therapy seems to be an effective, safe, and well-tolerated treatment option for patients with PP/early-stage MF. PMID:24502428

Aydogan, Kenan; Yazici, Serkan; Balaban Adim, Saduman; Tilki Gunay, Isil; Budak, Ferah; Saricaoglu, Hayriye; Tunali, Sukran; Bulbul Baskan, Emel

2014-01-01

346

Towards non-invasive diagnostic imaging of early-stage Alzheimer's disease.  

PubMed

One way to image the molecular pathology in Alzheimer's disease is by positron emission tomography using probes that target amyloid fibrils. However, these fibrils are not closely linked to the development of the disease. It is now thought that early-stage biomarkers that instigate memory loss are composed of A? oligomers. Here, we report a sensitive molecular magnetic resonance imaging contrast probe that is specific for A? oligomers. We attach oligomer-specific antibodies onto magnetic nanostructures and show that the complex is stable and binds to A? oligomers on cells and brain tissues to give a magnetic resonance imaging signal. When intranasally administered to an Alzheimer's disease mouse model, the probe readily reached hippocampal A? oligomers. In isolated samples of human brain tissue, we observed a magnetic resonance imaging signal that distinguished Alzheimer's disease from controls. Such nanostructures that target neurotoxic A? oligomers are potentially useful for evaluating the efficacy of new drugs and ultimately for early-stage Alzheimer's disease diagnosis and disease management. PMID:25531084

Viola, Kirsten L; Sbarboro, James; Sureka, Ruchi; De, Mrinmoy; Bicca, Maíra A; Wang, Jane; Vasavada, Shaleen; Satpathy, Sreyesh; Wu, Summer; Joshi, Hrushikesh; Velasco, Pauline T; MacRenaris, Keith; Waters, E Alex; Lu, Chang; Phan, Joseph; Lacor, Pascale; Prasad, Pottumarthi; Dravid, Vinayak P; Klein, William L

2015-01-01

347

Early stages of Ti-O cluster growth on carbon nanotubes by ab initio calculations.  

PubMed

Ti-O combined with carbon nanotubes are excelled candidates for many technological applications. The early stages of growth comprise octahedral (Oh) anatase or rutile nanoparticles depending on the tetrahedral (Th) precursors. However, the underline mechanisms are still unknown. Here, we present results of a systematic study of Th or Oh clusters on (4,0) and (8,0). We found that although the Th may exist in several conformations, with well localized electronic states, the Oh is unstable. We found that due to charge localization and the emergence of C dangling bonds at the Fermi level, Th could be considered as more active compared to Oh that adopts the tube's C(2p)-C(2p) ?-like features. In addition, when parallel to the tubes and along the zigzag chiral direction, the linear rutile-like trimers on zigzag (8,0), armchair (5,5), and (3,0)@(12,0) multiwall were clearly found to be energetically favored, while when vertically aligned, equi-probable rutile or spinal anatase-like growth is expected. At the Fermi level, the charge is localized at the Ti-O trimer, when on (5,5) and (3,0)@(12,0) cases, rendering Ti-O active. These results could enlighten the early stages of Ti-O growth on SWCNT providing useful information in the field of nanoelectronics and nanotechnology. PMID:24044643

Gialampouki, M A; Lekka, Ch E

2013-10-10

348

Metacognitive Monitoring and Dementia: How Intrinsic and Extrinsic Cues Influence Judgments of Learning in People With Early-Stage  

E-print Network

of Learning in People With Early-Stage Alzheimer's Disease Ayanna K. Thomas and Meeyeon Lee Tufts University metamemory monitoring predictions. Keywords: metacognition, Alzheimer's disease, aging, memory Metamemory stage Dementia of the Alzheimer's Type (DAT). Method: In three experiments we examined the influence

Patel, Aniruddh D.

349

Validation of a Proliferation-based Expression Signature as Prognostic Marker in Early Stage Lung Adenocarcinoma  

PubMed Central

PURPOSE New prognostic markers to guide treatment decisions in early stage non-small cell lung cancer are necessary to improve patient outcomes. In this report, we assess the utility of a pre-defined mRNA expression signature of cell cycle progression genes (CCP score) to define 5-year risk of lung cancer related death in patients with early stage lung adenocarcinoma. EXPERIMENTAL DESIGN A CCP score was calculated from the mRNA expression levels of 31 proliferation genes in stage I and II tumor samples from two public microarray data sets (Director’s Consortium (DC) and GSE31210). The same gene set was tested by quantitative PCR in 381 formalin-fixed paraffin-embedded (FFPE) primary tumors. Association of the CCP score with outcome was assessed by Cox proportional hazards analysis. RESULTS In univariate analysis the CCP score was a strong predictor of cancer-specific survival in both the DC cohort (p=0.00014, HR 2.08, 95%CI 1.43–3.02) and GSE31210 (p=0.0010, HR 2.25, 95%CI 1.42–3.56). In multivariate analysis the CCP score remained the dominant prognostic marker in the presence of clinical variables (p=0.0022, HR 2.02, 95%CI 1.29–3.17 in DC, p=0.0026, HR 2.16, 95%CI 1.32–3.53 in GSE31210). On a quantitative PCR platform the CCP score maintained highly significant prognostic value in FFPE derived mRNA from clinical samples in both univariate (p=0.00033, HR 2.10, 95%CI 1.39–3.17) and multivariate analyses (p=0.0071, HR 1.92, 95%CI 1.18–3.10). CONCLUSIONS The CCP score is a significant predictor of lung cancer death in early stage lung adenocarcinoma treated with surgery and may be a valuable tool in selecting patients for adjuvant treatment. PMID:24048333

Wistuba, Ignacio I.; Behrens, Carmen; Lombardi, Francesca; Wagner, Susanne; Fujimoto, Junya; Raso, M. Gabriela; Spaggiari, Lorenzo; Galetta, Domenico; Riley, Robyn; Hughes, Elisha; Reid, Julia; Sangale, Zaina; Swisher, Steven G.; Kalhor, Neda; Moran, Cesar A.; Gutin, Alexander; Lanchbury, Jerry. S.; Barberis, Massimo; Kim, Edward S.

2013-01-01

350

Properties of large scale plasma flow during the early stage of the plasmaspheric refilling  

NASA Technical Reports Server (NTRS)

The objective is to better characterize the macroscopic properties of the interhemisphere plasma flow by solving a more complete set of hydrodynamic equations than that solved previously. Specifically, the ion continuity, momentum and energy equations were solved for the plasma flow along the closed magnetic field lines. During the initial stage of the supersonic outflow in the equatorial region, the ions cool substantially. Using the hydrodynamic model for the large-scale plasma flow, the dynamics of shocks was examined which form in the geomagnetic flux tubes during the early stages of refilling. These shocks are more like those forming in neutral gases than the electrostatic shocks driven by microinstabilities involving ion-ion interaction. Therefore, the shocks seen in the hydrodynamic model are termed as hydrodynamic shocks. Such shocks are generally unsteady and therefore the usual shock jump conditions given by Rankine-Hugoniot relations are not strictly applicable to them. The density, flow velocity and temperature structures associated with the shocks are examined for both asymmetrical and symmetrical flows. In the asymmetrical flow the outflow from one of two conjugate ionospheres is dominant. On the other hand, in the symmetrical case outflows from the two ionospheric sources are identical. Both cases are treated by a two-stream model. In the late type of flow, the early-time refilling shows a relaxation type of oscillation, which is driven by the large-scale interactions between the two identical streams. After this early stage, the resulting temperature structure shows some interesting features. In the equatorial region the streams are isothermal, but in the off-equatorial regions the streams have quite different temperatures, and also densities and flow velocities. The dense and slow stream is found to be warmer than the low-density fast stream. In the late stage of refilling, the temperature is found to steadily increase from the conjugate ionospheres towards the equator; the equatorial temperature is found to be as high as about 8000 K compared to the ionospheric temperature of 3600 K.

Singh, Nagendra; Craven, P.; Torr, D. G.; Richards, P. G.

1990-01-01

351

The last one heard: the importance of an early stage participatory evaluation for programme implementation.  

PubMed

BackgroundThe systematic involvement of project beneficiaries in community maternal and child health programmes remains low and limited, especially during the formative stages of the project cycle. Understanding how positive and negative feedback obtained from communities can subsequently be used to inform and iterate existing programmes are important steps towards ensuring the success of community health workers for maternal and child health programming and ultimately, for improving health outcomes.MethodsThe study took place over a period of 4 weeks in North Rukiga, Kabale District of southwestern Uganda. Using a cross-sectional qualitative study that employed an epistemological approach of phenomenology, 9 focus group discussions and 8 in-depth interviews were conducted with a total of 76 female participants across 6 different sites. Women were identified as either users or non-users of the maternal and child health programme. Purposeful sampling was employed to recruit women from 6 different locations within the programme catchment area. Translated and transcribed transcripts were subjected to a bottom-up thematic analysis using Nvivo 10 Software, whereby themes were arrived at inductively.ResultsPredominant themes emerging from the focus groups and key informant interviews identified early trends in programme strengths. Beneficiaries reported confidence in both the programme and the relationships they had forged with community health workers, exhibited pride in the knowledge they had received, and described improved spousal involvement. Beneficiaries also identified a number of programme challenges including barriers to adopting the behaviours promoted by the programme, and highlighted issues with programme dependency and perceived ownership. It also emerged that community health workers were not reaching the entire population of intended programme beneficiaries.ConclusionsThis research provides support for the importance of an early stage participatory evaluation of beneficiaries¿ perceptions of newly initiated health programmes. Our results support how evaluations conducted in the early phases of programme implementation can provide valuable, timely feedback as well as yield recommendations for programme adjustment or re-alignment, and in turn, better meet end-user expectations. Potential reasons for the observed lack of community participation in early stages of programme implementation are considered. PMID:25253191

Gilmore, Brynne; Vallières, Frédérique; McAuliffe, Eilish; Tumwesigye, Nazarius; Muyambi, Gilbert

2014-09-26

352

Scrub-successional bird community dynamics in young and mature longleaf pine-wiregrass savannahs  

USGS Publications Warehouse

Public agencies are required to manage for threatened and endangered species and for biodiversity. However, at times, management for threatened and endangered species precludes consideration of other species. We investigated how managing for red-cockaded woodpeckers (Picoides borealis) and biodiversity at the Savannah River Site (SRS), South Carolina, affected communities of bird species that use early-successional scrub habitat (hereafter, scrub-successional species). Management for red-cockaded woodpeckers at the SRS involved both (1) manipulating mature longleaf pine (Pinus palustris)-wiregrass (Andropogon spp.) stands via canopy thinning, removal of midstory trees, and prescribed burning; and (2) even-aged timber harvesting. The former management practice encouraged red-cockaded woodpeckers to establish new colonies in previously unoccupied stands (hereafter, 'recruitment' stands). The latter management practice is used to remove off-site planted pines and replant with preferred longleaf pines. We conducted a constant-effort mist net study in recruitment and regenerating stands (stands clearcut and planted with longleaf pine) during the breeding seasons of 1995-96. We hypothesized that the scrub-successional bird community in recruitment stands would have greater species richness and higher survival and reproductive rates per species than in regenerating stands. However, recruitment stands always had fewer scrub-successional species (1995:36 species; 1996:31 species) than regenerating stands (1995:54 species; 1996:55 species), and all species that occurred in recruitment stands also occurred in regenerating stands. Species which commonly occurred in both recruitment and regenerating stands had similar adult:juvenile ratios (P > 0.15) and relative proportion of adults in breeding condition (P > 0.05). We detected no difference in survival rates of Bachman's sparrows (Aimophila aestivalis), indigo buntings (Passerina cyanea), and of 'combined' scrub-successional birds between stand types (P > 0.05). We found that even-aged forestry is an important management practice for maintaining and increasing avian biodiversity on public lands, as well as an acceptable management practice for red-cockaded woodpeckers.

Krementz, D.G.; Christie, J.S.

1999-01-01

353

Lack of miRNA Misregulation at Early Pathological Stages in Drosophila Neurodegenerative Disease Models.  

PubMed

Late onset neurodegenerative diseases represent a major public health concern as the population in many countries ages. Both frequent diseases such as Alzheimer disease (AD, 14% incidence for 80-84?year-old Europeans) or Parkinson disease (PD, 1.4% prevalence for >55?years old) share, with other low-incidence neurodegenerative pathologies such as spinocerebellar ataxias (SCAs, 0.01% prevalence) and frontotemporal lobar degeneration (FTLD, 0.02% prevalence), a lack of efficient treatment in spite of important research efforts. Besides significant progress, studies with animal models have revealed unexpected complexities in the degenerative process, emphasizing a need to better understand the underlying pathological mechanisms. Recently, microRNAs (miRNAs), a class of small regulatory non-coding RNAs, have been implicated in some neurodegenerative diseases. The current data supporting a role of miRNAs in PD, tauopathies, dominant ataxias, and FTLD will first be discussed to emphasize the different levels of the pathological processes which may be affected by miRNAs. To investigate a potential involvement of miRNA dysregulation in the early stages of these neurodegenerative diseases we have used Drosophila models for seven diseases (PD, 3 FTLD, 3 dominant ataxias) that recapitulate many features of the human diseases. We performed deep sequencing of head small RNAs after 3?days of pathological protein expression in the fly head neurons. We found no evidence for a statistically significant difference in miRNA expression in this early stage of the pathological process. In addition, we could not identify small non-coding CAG repeat RNAs (sCAG) in polyQ disease models. Thus our data suggest that transcriptional deregulation of miRNAs or sCAG is unlikely to play a significant role in the initial stages of neurodegenerative diseases. PMID:23115562

Reinhardt, Anita; Feuillette, Sébastien; Cassar, Marlène; Callens, Céline; Thomassin, Hélène; Birman, Serge; Lecourtois, Magalie; Antoniewski, Christophe; Tricoire, Hervé

2012-01-01

354

Lack of miRNA Misregulation at Early Pathological Stages in Drosophila Neurodegenerative Disease Models  

PubMed Central

Late onset neurodegenerative diseases represent a major public health concern as the population in many countries ages. Both frequent diseases such as Alzheimer disease (AD, 14% incidence for 80–84?year-old Europeans) or Parkinson disease (PD, 1.4% prevalence for >55?years old) share, with other low-incidence neurodegenerative pathologies such as spinocerebellar ataxias (SCAs, 0.01% prevalence) and frontotemporal lobar degeneration (FTLD, 0.02% prevalence), a lack of efficient treatment in spite of important research efforts. Besides significant progress, studies with animal models have revealed unexpected complexities in the degenerative process, emphasizing a need to better understand the underlying pathological mechanisms. Recently, microRNAs (miRNAs), a class of small regulatory non-coding RNAs, have been implicated in some neurodegenerative diseases. The current data supporting a role of miRNAs in PD, tauopathies, dominant ataxias, and FTLD will first be discussed to emphasize the different levels of the pathological processes which may be affected by miRNAs. To investigate a potential involvement of miRNA dysregulation in the early stages of these neurodegenerative diseases we have used Drosophila models for seven diseases (PD, 3 FTLD, 3 dominant ataxias) that recapitulate many features of the human diseases. We performed deep sequencing of head small RNAs after 3?days of pathological protein expression in the fly head neurons. We found no evidence for a statistically significant difference in miRNA expression in this early stage of the pathological process. In addition, we could not identify small non-coding CAG repeat RNAs (sCAG) in polyQ disease models. Thus our data suggest that transcriptional deregulation of miRNAs or sCAG is unlikely to play a significant role in the initial stages of neurodegenerative diseases. PMID:23115562

Reinhardt, Anita; Feuillette, Sébastien; Cassar, Marlène; Callens, Céline; Thomassin, Hélène; Birman, Serge; Lecourtois, Magalie; Antoniewski, Christophe; Tricoire, Hervé

2012-01-01

355

A Candida albicans early stage biofilm detachment event in rich medium  

PubMed Central

Background Dispersal from Candida albicans biofilms that colonize catheters is implicated as a primary factor in the link between contaminated catheters and life threatening blood stream infections (BSI). Appropriate in vitro C. albicans biofilm models are needed to probe factors that induce detachment events. Results Using a flow through system to culture C. albicans biofilms we characterized a detachment process which culminates in dissociation of an entire early stage biofilm from a silicone elastomer surface. We analyzed the transcriptome response at time points that bracketed an abrupt transition in which a strong adhesive association with the surface is weakened in the initial stages of the process, and also compared batch and biofilm cultures at relevant time points. K means analysis of the time course array data revealed categories of genes with similar patterns of expression that were associated with adhesion, biofilm formation and glycoprotein biosynthesis. Compared to batch cultures the biofilm showed a pattern of expression of metabolic genes that was similar to the C. albicans response to hypoxia. However, the loss of strong adhesion was not obviously influenced by either the availability of oxygen in the medium or at the silicone elastomer surface. The detachment phenotype of mutant strains in which selected genes were either deleted or overexpressed was characterized. The microarray data indicated that changes associated with the detachment process were complex and, consistent with this assessment, we were unable to demonstrate that transcriptional regulation of any single gene was essential for loss of the strong adhesive association. Conclusion The massive dispersal of the early stage biofilm from a biomaterial surface that we observed is not orchestrated at the level of transcriptional regulation in an obvious manner, or is only regulated at this level by a small subpopulation of cells that mediate adhesion to the surface. PMID:19187560

2009-01-01

356

Early-Stage Young Breast Cancer Patients: Impact of Local Treatment on Survival  

SciTech Connect

Purpose: In young women, breast-conserving therapy (BCT), i.e., lumpectomy followed by radiotherapy, has been associated with an increased risk of local recurrence. Still, there is insufficient evidence that BCT impairs survival. The aim of our study was to compare the effect of BCT with mastectomy on overall survival (OS) in young women with early-stage breast cancer. Methods and Materials: From two Dutch regional population-based cancer registries (covering 6.2 million inhabitants) 1,453 women <40 years with pathologically T1N0-1M0 breast cancer were selected. Cox regression survival analysis was used to study the effect of local treatment (BCT vs. mastectomy) stratified for nodal stage on survival and corrected for tumor size, age, period of diagnosis, and use of adjuvant systemic therapy. Results: With a median follow-up of 9.6 years, 10-year OS was 83% after BCT and 78% after mastectomy, respectively (unadjusted hazard ratio [HR], 1.37; 95% confidence interval [CI], 1.09-1.72). In N0-patients, 10-year OS was 84% after BCT and 81% after mastectomy and local treatment was not associated with differences in OS (HR 1.19; 95% CI, 0.89-1.58; p = 0.25). Within the N1-patient group, OS was better after BCT compared with mastectomy, 79% vs. 71% at 10 years (HR 1.91; 95% CI, 1.28-2.84; p = 0.001) and in patients treated with adjuvant hormonal therapy (HR 0.34; 95% CI, 0.18-0.66; p = 0.001). Conclusions: In this large population-based cohort of early-stage young breast cancer patients, 10-year OS was not impaired after BCT compared with mastectomy. Patients with 1 to 3 positive lymph nodes had better prognosis after BCT than after mastectomy.

Bantema-Joppe, Enja J. [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Munck, Linda de [Comprehensive Cancer Center North East, Groningen/Enschede (Netherlands); Visser, Otto [Comprehensive Cancer Center Amsterdam, Amsterdam (Netherlands); Willemse, Pax H.B. [Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Langendijk, Johannes A. [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Siesling, Sabine [Comprehensive Cancer Center North East, Groningen/Enschede (Netherlands); Department of Health Technology and Services Research, University of Twente, Enschede (Netherlands); Maduro, John H., E-mail: j.h.maduro@rt.umcg.nl [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands)

2011-11-15

357

Tangential Radiotherapy Without Axillary Surgery in Early-Stage Breast Cancer: Results of a Prospective Trial  

SciTech Connect

Purpose: To determine the risk of regional-nodal recurrence in patients with early-stage, invasive breast cancer, with clinically negative axillary nodes, who were treated with breast-conserving surgery, 'high tangential' breast radiotherapy, and hormonal therapy, without axillary surgery or the use of a separate nodal radiation field. Methods and Materials: Between September 1998 and November 2003, 74 patients who were {>=}55 years of age with Stage I-II clinically node-negative, hormone-receptor-positive breast cancer underwent tumor excision to negative margins without axillary surgery as a part of a multi-institutional prospective study. Postoperatively, all underwent high-tangential, whole-breast radiotherapy with a boost to the tumor bed, followed by 5 years of hormonal therapy. Results: For the 74 patients enrolled, the median age was 74.5 years, and the median pathologic tumor size was 1.2 cm. Lymphatic vessel invasion was present in 5 patients (7%). At a median follow-up of 52 months, no regional-nodal failures or ipsilateral breast recurrences had been identified (95% confidence interval, 0-4%). Eight patients died, one of metastatic disease and seven of other causes. Conclusion: In this select group of mainly older patients with early-stage hormone-responsive breast cancer and clinically negative axillary nodes, treatment with high-tangential breast radiotherapy and hormonal therapy, without axillary surgery, yielded a low regional recurrence rate. Such patients might be spared more extensive axillary treatment (axillary surgery, including sentinel node biopsy, or a separate nodal radiation field), with its associated time, expense, and morbidity.

Wong, Julia S. [Department of Radiation Oncology, Dana-Farber/Brigham and Women's Cancer Center, Boston, MA (United States)], E-mail: jwong@lroc.harvard.edu; Taghian, Alphonse G. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Bellon, Jennifer R. [Department of Radiation Oncology, Dana-Farber/Brigham and Women's Cancer Center, Boston, MA (United States); Keshaviah, Aparna [Department of Biostatistics and Computational Biology, Dana-Farber/Brigham and Women's Cancer Center, Boston, MA (United States); Smith, Barbara L. [Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Winer, Eric P. [Department of Medical Oncology, Dana-Farber/Brigham and Women's Cancer Center, Boston, MA (United States); Silver, Barbara; Harris, Jay R. [Department of Radiation Oncology, Dana-Farber/Brigham and Women's Cancer Center, Boston, MA (United States)

2008-11-01

358

Successional trends in Sonoran Desert abandoned agricultural fields in northern Mexico  

USGS Publications Warehouse

Excessive ground-water use and saline intrusion to the aquifer led, in less than three decades, to an increase in abandoned agricultural fields at La Costa de Hermosillo, within the Sonoran Desert. Using a chronosequence from years since abandonment, patterns of field succession were developed. Contrary to most desert literature, species replacement was found, both in fields with and without saline intrusion. Seasonal photosynthetic capacity as well as water and nitrogen use efficiencies were different in dominant early and late successional plant species. These ecological findings provided a framework for a general explanation of species dominance and replacement within abandoned agricultural fields in the Sonoran Desert. ?? 2004 Elsevier Ltd. All rights reserved.

Castellanos, A.E.; Martinez, M.J.; Llano, J.M.; Halvorson, W.L.; Espiricueta, M.; Espejel, I.

2005-01-01

359

Effect of chronic copper and pentachlorophenol exposure to early life stages of Xenopus laevis  

SciTech Connect

An evaluation of the effects of low-level copper and pentachlorophenol exposure on various early life stages of the South African clawed frog, Xenopus laevis was performed using stage-specific and long-term continuous exposures. Stage-specific exposure experiments were conducted such that separate subsets of embryos and larvae from the same clutch were exposed to two toxicants, copper and pentachlorophenol, from 0 d to 4 d (standard Frog Embryo Teratagenesis Assay Xenopus [FETAX]), 4 d to 8 d, 8 d to 12 d, and 12 d to 16 d. Results from two separate concentration-response experiments indicated that sensitivity to either toxicant increased in each successive time period. Continuous exposure studies conducted for 60 to 75 days indicated that copper, but not pentachlorophenol induced reduction deficiency malformations of the hind limb at concentrations as low as 0.05 mg/L. Pentachlorophenol concentrations as low as 0.5/{micro}g/L inhibited tail resorption. However, copper did not adversely affect the process of tail resorption. These results indicated that studies evaluating longer-term developmental processes are important in ecological hazard evaluation.

Fort, D.J.; Stover, E.L. [Stover Group, Stillwater, OK (United States)

1995-12-31

360

Hemostasis during the early stages of trauma: comparison with disseminated intravascular coagulation  

PubMed Central

Introduction We tested two hypotheses that disseminated intravascular coagulation (DIC) and acute coagulopathy of trauma-shock (ACOTS) in the early phase of trauma are similar disease entities and that the DIC score on admission can be used to predict the prognosis of patients with coagulopathy of trauma. Methods We conducted a retrospective study of 562 trauma patients, including 338 patients whose data were obtained immediately after admission to the emergency department. We collected serial data for the platelet counts, global markers of coagulation and fibrinolysis, and antithrombin levels. DIC was diagnosed according to the Japanese Association for Acute Medicine (JAAM) DIC scoring system, and ACOTS was defined as a prothrombin-time ratio of >1.2. Results The higher levels of fibrin/fibrinogen degradation products (FDP) and D-dimer and greater FDP/D-dimer ratios in the DIC patients suggested DIC with the fibrinolytic phenotype. The DIC patients with the fibrinolytic phenotype exhibited persistently lower platelet counts and fibrinogen levels, increased prothrombin time ratios, higher FDP and D-dimer levels, and lower antithrombin levels compared with the non-DIC patients on arrival to the emergency department and during the early stage of trauma. Almost all ACOTS patients met the criteria for a diagnosis of DIC; therefore, the same changes were observed in the platelet counts, global markers of coagulation and fibrinolysis, and antithrombin levels as noted in the DIC patients. The JAAM DIC score obtained immediately after arrival to the emergency department was an independent predictor of massive transfusion and death due to trauma and correlated with the amount of blood transfused. Conclusions Patients who develop DIC with the fibrinolytic phenotype during the early stage of trauma exhibit consumption coagulopathy associated with increased fibrin(ogen)olysis and lower levels of antithrombin. The same is true in patients with ACOTS. The JAAM DIC score can be used to predict the prognosis of patients with coagulopathy of trauma. PMID:24708802

2014-01-01

361

Rain forest fragmentation and the proliferation of successional trees.  

PubMed

The effects of habitat fragmentation on diverse tropical tree communities are poorly understood. Over a 20-year period we monitored the density of 52 tree species in nine predominantly successional genera (Annona, Bellucia, Cecropia, Croton, Goupia, Jacaranda, Miconia, Pourouma, Vismia) in fragmented and continuous Amazonian forests. We also evaluated the relative importance of soil, topographic, forest dynamic, and landscape variables in explaining the abundance and species composition of successional trees. Data were collected within 66 permanent 1-ha plots within a large (approximately 1000 km2) experimental landscape, with forest fragments ranging from 1 to 100 ha in area. Prior to forest fragmentation, successional trees were uncommon, typically comprising 2-3% of all trees (> or =10 cm diameter at breast height [1.3 m above the ground surface]) in each plot. Following fragmentation, the density and basal area of successional trees increased rapidly. By 13-17 years after fragmentation, successional trees had tripled in abundance in fragment and edge plots and constituted more than a quarter of all trees in some plots. Fragment age had strong, positive effects on the density and basal area of successional trees, with no indication of a plateau in these variables, suggesting that successional species could become even more abundant in fragments over time. Nonetheless, the 52 species differed greatly in their responses to fragmentation and forest edges. Some disturbance-favoring pioneers (e.g., Cecropia sciadophylla, Vismia guianensis, V. amazonica, V. bemerguii, Miconia cf. crassinervia) increased by >1000% in density on edge plots, whereas over a third (19 of 52) of all species remained constant or declined in numbers. Species responses to fragmentation were effectively predicted by their median growth rate in nearby intact forest, suggesting that faster-growing species have a strong advantage in forest fragments. An ordination analysis revealed three main gradients in successional-species composition across our study area. Species gradients were most strongly influenced by the standlevel rate of tree mortality on each plot and by the number of nearby forest edges. Species-composition also varied significantly among different cattle ranches, which differed in their surrounding matrices and disturbance histories. These same variables were also the best predictors of total successional-tree abundance and species richness. Successional-tree assemblages in fragment interior plots (>150 m from edge), which are subjected to fragment area effects but not edge effects, did not differ significantly from those in intact forest, indicating that area effects per se had little influence on successional trees. Soils and topography also had little discernable effect on these species. Collectively, our results indicate that successional-tree species proliferate rapidly in fragmented Amazonian forests, largely as a result of chronically elevated tree mortality near forest edges and possibly an increased seed rain from successional plants growing in nearby degraded habitats. The proliferation of fast-growing successional trees and correlated decline of old-growth trees will have important effects on species composition, forest dynamics, carbon storage, and nutrient cycling in fragmented forests. PMID:16637371

Laurance, William F; Nascimento, Henrique E M; Laurance, Susan G; Andrade, Ana C; Fearnside, Philip M; Ribeiro, José E L; Capretz, Robson L

2006-02-01

362

Leaves of pioneer and later-successional trees have similar lifetime carbon gain in tropical secondary forest.  

PubMed

Different life history strategies among tropical rain forest species are generally related to inherent trade-offs in leaf and crown traits, with early-successional species having traits that facilitate high productivity but a relatively wasteful use of resources and shade-tolerant later-successional species exhibiting the opposite strategy. But the degree to which these trait differences contribute to short- and long-term carbon gain of different species that coexist in natural forest has not been quantitatively scaled. We applied a canopy model in combination with measurements of canopy structure, mass distribution, and leaf photosynthesis to determine whole-plant daily photosynthesis (P(pl)) of individuals of three short-lived pioneers (SLP), four later-successional species, and three lianas growing together in a 0.5-, 2-, and 3-yr-old secondary tropical forest stand. Whole-plant daily photosynthesis per unit leaf mass (P(lfm)) and aboveground mass (P(m)) were assumed to indicate daily returns on investment at the leaf and crown level. By integrating these calculations with measured leaf longevities, we determined the lifetime carbon gain per unit leaf mass. Vegetation height and leaf area index increased with stand age. Two of the SLPs, Trema and Ochroma, increasingly dominated the top of the vegetation. In the 0.5-yr-old stand, these species also had the highest P(m) and P(lfm) values. Whole-plant daily photosynthesis per unit leaf mass tended to decline with stand age but much more strongly so in the later-successional species than in the SLP. Leaf longevity was not significantly correlated with individual leaf traits (e.g., specific leaf area or leaf N content) but was strongly and negatively correlated with P(lfm) in the youngest stand. Later-successional species had considerably greater leaf longevities than SLP. Lifetime carbon gain per unit leaf mass, however, was relatively similar between the different species. Thus due to the strong negative correlation that exists between daily leaf productivity (P(lfm)) and longevity, short-lived pioneers and later-successional species achieve similar lifetime carbon gain per unit leaf mass in natural secondary forest. This could help explain why the slower-growing later-successional species are able to persist during the first years of succession. PMID:20462124

Selaya, N Galia; Anten, Niels P R

2010-04-01

363

Ultrastructure of Fibre and Parenchyma Cell Walls During Early Stages of Culm Development in Dendrocalamus asper  

PubMed Central

• Background and Aims The anatomy of bamboo culms and the multilayered structure of fibre cell walls are known to be the main determinant factors for its physical and mechanical properties. Studies on the bamboo cell wall have focussed mainly on fully elongated and mature fibres. The main aim of this study was to describe the ultrastructure of primary and secondary cell walls in culm tissues of Dendrocalamus asper at different stages of development. • Methods The development of fibre and parenchyma tissues was classified into four stages based on light microscopy observations made in tissues from juvenile plants. The stages were used as a basis for transmission electron microscopy study on the ultrastructure of the cell wall during the process of primary and early secondary cell wall formation. Macerations and phloroglucinol–HCl staining were employed to investigate fibre cell elongation and fibre cell wall lignification, respectively. • Key Results The observations indicated that the primary wall is formed by the deposition of two distinct layers during the elongation of the internode and that secondary wall synthesis may begin before the complete cessation of internode and fibre elongation. Elongation was followed by a maturation phase characterized by the deposition of multiple secondary wall layers, which varied in number according to the cell type, location in the culm tissue and stage of shoot development. Lignification of fibre cell walls started at the period prior to the cessation of internode elongation. • Conclusions The structure of the primary cell wall was comprised of two layers. The fibre secondary cell wall began to be laid down while the cells were still undergoing some elongation, suggesting that it may act to cause the slow-down and eventual cessation of cell elongation. PMID:15665037

GRITSCH, CRISTINA SANCHIS; MURPHY, RICHARD J.

2005-01-01

364

Subduction-related metamorphism beneath ophiolites (Oman) and during early stages of continental collision (Himalaya)  

NASA Astrophysics Data System (ADS)

Subduction-related metamorphism occurs beneath ophiolites (Oman), beneath island arcs (Kohistan) and during the early stages of continental collision (Kaghan, Tso Morari; Himalaya). Ophiolite obduction necessarily involves subduction of first oceanic, then continental crust to mantle depths beneath the ophiolite. In Oman an inverted pressure and temperature profile is exposed beneath the Semail ophiolite from garnet+clinopyroxene-bearing granulite to hornblende+plagioclase amphibolite down through epidote amphibolite and a variety of greenschist facies meta-sediments, dominantly cherts, marbles and quartzites. Thermobarometry on Grt+Cpx-bearing amphibolites immediately beneath the contact with mantle sequence harzburgites shows that the upper sole rocks formed at PT conditions of 770-900°C and 11-13 kbar, equivalent to depths of 30-40 km in oceanic lithosphere. Heat for metamorphism can only have been derived from the overlying mantle peridotites. Pressures are higher than can be accounted for by the thickness of the preserved ophiolite (15-20 km). Timing of peak metamorphism was synchronous with formation of the ophiolite gabbroic - trondhjemite crustal sequence and eruption of the pillow lavas (Cenomanian; 96-95 Ma). During the later stages of obduction the continental margin was dragged down to depths of nearly 100 km and basaltic sills within calc-schists were converted to eclogites (20-25 kbar; 500-560oC; 79.1 Ma), then exhumed back up the same subduction channel. Apparent 'extensional' fabrics throughout the HP units are related to upward flow of deeply buried rocks in a wholly compressional environment. Eclogites in a similar structural position occur along the Himalaya in the northernmost exposures of Indian plate rocks. These eclogites formed either during the latest stage of ophiolite obduction or the earliest stage of continental collision.

Searle, Mike; Waters, David; Cowan, Robert; Cherry, Alan; Cooper, Charles

2014-05-01

365

The effect of flurbiprofen on the development of anencephaly in early stage chicken embryos.  

PubMed

Objective. The study investigated the effect of flurbiprofen on the development of anencephaly in early stage chicken embryos. Material and methods. We looked at four groups with a total of 36 embryos. There was a control group, a normal saline group, a normal-dose group and a high-dose group with ten, ten, eight and eight eggs with embryo respectively. Results. Two embryos in the control group, studied with light microscopy at 48 h, were consistent with 28-29 hours' incubation in the Hamburger-Hamilton System. They had open neural tubes. The other embryos in this group were considered normal. One embryo in the normal saline group was on the occlusion stage at 48 h. One embryo showed an open neural tube. They were compatible with 28-29 hours' incubation in the Hamburger-Hamilton system. The remaining eight embryos showed normal development. In the normal dose group, one embryo showed underdevelopment of the embryonic disc and the embryo was dead. In four embryos, the neural tubes were open. One cranial malformation was found that was complicated with anencephaly in one embryo. In two embryos the neural tubes were closed, as they showed normal development, and they reached their expected stages according to the Hamburger-Hamilton classification. There was no malformation or growth retardation. Four experimental embryos were anencephalic in the high dose group, and three embryos had open neural tubes. One embryo exhibited both anencephaly and a neural tube closure defect. None of the embryos in this group showed normal development. Conclusions. Even the usual therapeutic doses of flurbiprofen increased the risk of neural tube defect. Flurbiprofen was found to significantly increase the risk of anencephaly. The provision of improved technical materials and studies with larger sample sizes will reveal the stage of morphological disruption during the development of embryos. PMID:25365663

Ozeren, Ersin; Er, Uygur; Güvenç, Yahya; Demirci, Adnan; Ar?kök, Ata Türker; Senveli, Engin; Ergün, Rüçhan Behzat

2014-11-01

366

Amygdalohippocampal MR volume measurements in the early stages of Alzheimer disease  

SciTech Connect

To evaluate the accuracy of hippocampal and amygdala volume measurements in diagnosing patients in the early stages of Alzheimer disease. Measurements of the hippocampal formation, amygdala, amygdalohippocampal complex (the two measurements summed), caudate nucleus, and ventricles, normalized for total intracranial volume, were obtained on coronal sections (1.5 T, 400/13 [repetition time/echo time], 5 mm) of 13 patients in the mild (minimental status {ge} 21) and five patients in the moderate stages of Alzheimer disease (10 < minimental status < 21), and eight age-matched control subjects. For patients with a minimental status score of 21 or greater, atrophy was significant for the amygdala and hippocampal formation (-36% and -25% for amygdala/total intracranial volume and hippocampal formation/total intracranial volume, respectively), but not for the caudate nucleus. No significant ventricular enlargement was found. For patients with a minimental status score less than 21, atrophy was more severe in all structures studied (amygdala/total intracranial volume -40%; hippocampal formation/total intracranial volume, -45%; caudate nucleus/total intracranial volume, -21%), and ventricles were enlarged (63%). No overlap was found between Alzheimer disease and control values for the amygdalohippocampal volume, even in the mild stages of the disease. In Alzheimer disease patients, hippocampal formation volumes correlated with the minimental status. Hippocampal and amygdala atrophy is marked and significant in the mild stages of Alzheimer disease. Volumetric measurements of the amygdala and the amygdalohippocampal complex appear more accurate than those of the hippocampal formation alone in distinguishing patients with Alzheimer disease. 46 refs., 8 figs., 2 tabs.

Lehericy, S.; Baulac, M.; Chiras, J.; Pierot, L.; Martin, N.; Pillon, B.; Deweer, B.; Dubois, B.; Marsault, C. [Hopital de la Pitie-Salpetriere, Paris (France)

1994-05-01

367

Theta Oscillations Are Sensitive to Both Early and Late Conflict Processing Stages: Effects of Alcohol Intoxication  

PubMed Central

Prior neuroimaging evidence indicates that decision conflict activates medial and lateral prefrontal and parietal cortices. Theoretical accounts of cognitive control highlight anterior cingulate cortex (ACC) as a central node in this network. However, a better understanding of the relative primacy and functional contributions of these areas to decision conflict requires insight into the neural dynamics of successive processing stages including conflict detection, response selection and execution. Moderate alcohol intoxication impairs cognitive control as it interferes with the ability to inhibit dominant, prepotent responses when they are no longer correct. To examine the effects of moderate intoxication on successive processing stages during cognitive control, spatio-temporal changes in total event-related theta power were measured during Stroop-induced conflict. Healthy social drinkers served as their own controls by participating in both alcohol (0.6 g/kg ethanol for men, 0.55 g/kg women) and placebo conditions in a counterbalanced design. Anatomically-constrained magnetoencephalography (aMEG) approach was applied to complex power spectra for theta (4–7 Hz) frequencies. The principal generator of event-related theta power to conflict was estimated to ACC, with contributions from fronto-parietal areas. The ACC was uniquely sensitive to conflict during both early conflict detection, and later response selection and execution stages. Alcohol attenuated theta power to conflict across successive processing stages, suggesting that alcohol-induced deficits in cognitive control may result from theta suppression in the executive network. Slower RTs were associated with attenuated theta power estimated to ACC, indicating that alcohol impairs motor preparation and execution subserved by the ACC. In addition to their relevance for the currently prevailing accounts of cognitive control, our results suggest that alcohol-induced impairment of top-down strategic processing underlies poor self-control and inability to refrain from drinking. PMID:22952823

Kovacevic, Sanja; Azma, Sheeva; Irimia, Andrei; Sherfey, Jason; Halgren, Eric; Marinkovic, Ksenija

2012-01-01

368

Adjuvant (post-surgery) chemotherapy for early stage epithelial ovarian cancer  

PubMed Central

Background Epithelial ovarian cancer is diagnosed in 4500 women in the UK each year of whom 1700 will ultimately die of their disease.Of all cases 10% to 15% are diagnosed early when there is still a good possibility of cure. The treatment of early stage disease involves surgery to remove disease often followed by chemotherapy. The largest clinical trials of this adjuvant therapy show an overall survival (OS) advantage with adjuvant platinum-based chemotherapy but the precise role of this treatment in subgroups of women with differing prognoses needs to be defined. Objectives To systematically review the evidence for adjuvant chemotherapy in early stage epithelial ovarian cancer to determine firstly whether there is a survival advantage of this treatment over the policy of observation following surgery with chemotherapy reserved for treatment of disease recurrence, and secondly to determine if clinical subgroups of differing prognosis based on histological sub-type, or completeness of surgical staging, have more or less to gain from chemotherapy following initial surgery. Search methods We performed an electronic search using the Cochrane Gynaecological Cancer Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL 2011, Issue 3), MEDLINE (1948 to Aug week 5, 2011) and EMBASE (1980 to week 36, 2011). We developed the search strategy using free-text and medical subject headings (MESH). Selection criteria We selected randomised clinical trials that met the inclusion criteria set out based on the populations, interventions, comparisons and outcome measures. Data collection and analysis Two review authors independently extracted data and assessed trial quality. Disagreements were resolved by discussion with a third review author. We performed random-effects meta-analyses and subgroup analyses. Main results Five randomised controlled trials (RCTs), enrolling 1277 women, with a median follow-up of 46 to 121 months, met the inclusion criteria. Four trials were included in the meta-analyses and we considered them to be at a low risk of bias. Meta-analysis of five-year data from three trials indicated that women who received adjuvant platinum-based chemotherapy had better overall survival (OS) than those who did not (1008 women; hazard ratio (HR) 0.71; 95% confidence interval (CI) 0.53 to 0.93). Likewise, meta-analysis of five-year data from four trials indicated that women who received adjuvant chemotherapy had better progression-free survival (PFS) than those who did not (1170 women; HR 0.67; 95% CI 0.53 to 0.84). The trials included in these meta-analyses gave consistent estimates of the effects of chemotherapy. In addition, these findings were robust over time (10-year PFS: two trials, 925 women; HR 0.67; 95% CI 0.54 to 0.84). Subgroup analysis suggested that women who had optimal surgical staging of their disease were unlikely to benefit from adjuvant chemotherapy (HR for OS 1.22; 95% CI 0.63 to 2.37; two trials, 234 women) whereas those who had sub-optimal staging did (HR for OS 0.63; 95% CI 0.46 to 0.85; two trials, 772 women). One trial showed a benefit from adjuvant chemotherapy among women at high risk (HR for OS 0.48; 95% CI 0.32 to 0.72) but not among those at low/medium risk (HR for OS 0.95; 95% CI 0.54 to 1.66). However, these subgroup findings could be due to chance and should be interpreted with caution. Authors’ conclusions Adjuvant platinum-based chemotherapy is effective in prolonging the survival of the majority of patients who are assessed as having early (FIGO stage I/IIa) epithelial ovarian cancer. However, it may be withheld from women in whom there is well-differentiated encapsulated unilateral disease (stage 1a grade 1) or those with comprehensively staged Ib, well or moderately differentiated (grade 1/2) disease. Others with unstaged early disease or those with poorly differentiated tumours should be offered chemotherapy. A pragmatic approach may be necessary in clinical settings where optimal staging is not normally performed/achieved. In such settings, adjuvant chemotherap

Winter-Roach, Brett A; Kitchener, Henry C; Lawrie, Theresa A

2014-01-01

369

Efficacy of Intensity Modulated Radiation Therapy After Surgery in Early Stage of Esophageal Carcinoma;  

ClinicalTrials.gov

Esophageal Neoplasm; Esophageal Cancer TNM Staging Primary Tumor (T) T2; Esophageal Cancer TNM Staging Primary Tumor (T) T3; Esophageal Cancer TNM Staging Regional Lymph Nodes (N) N0; Esophageal Cancer TNM Staging Distal Metastasis (M) M0

2012-12-28

370

Inhibition of master transcription factors in pluripotent cells induces early stage differentiation  

PubMed Central

The potential for pluripotent cells to differentiate into diverse specialized cell types has given much hope to the field of regenerative medicine. Nevertheless, the low efficiency of cell commitment has been a major bottleneck in this field. Here we provide a strategy to enhance the efficiency of early differentiation of pluripotent cells. We hypothesized that the initial phase of differentiation can be enhanced if the transcriptional activity of master regulators of stemness is suppressed, blocking the formation of functional transcriptomes. However, an obstacle is the lack of an efficient strategy to block protein–protein interactions. In this work, we take advantage of the biochemical property of seventeen kilodalton protein (Skp), a bacterial molecular chaperone that binds directly to sex determining region Y-box 2 (Sox2). The small angle X-ray scattering analyses provided a low resolution model of the complex and suggested that the transactivation domain of Sox2 is probably wrapped in a cleft on Skp trimer. Upon the transduction of Skp into pluripotent cells, the transcriptional activity of Sox2 was inhibited and the expression of Sox2 and octamer-binding transcription factor 4 was reduced, which resulted in the expression of early differentiation markers and appearance of early neuronal and cardiac progenitors. These results suggest that the initial stage of differentiation can be accelerated by inhibiting master transcription factors of stemness. This strategy can possibly be applied to increase the efficiency of stem cell differentiation into various cell types and also provides a clue to understanding the mechanism of early differentiation. PMID:24434556

De, Debojyoti; Jeong, Myong-Ho; Leem, Young-Eun; Svergun, Dmitri I.; Wemmer, David E.; Kang, Jong-Sun; Kim, Kyeong Kyu; Kim, Sung-Hou

2014-01-01

371

Inhibition of master transcription factors in pluripotent cells induces early stage differentiation.  

PubMed

The potential for pluripotent cells to differentiate into diverse specialized cell types has given much hope to the field of regenerative medicine. Nevertheless, the low efficiency of cell commitment has been a major bottleneck in this field. Here we provide a strategy to enhance the efficiency of early differentiation of pluripotent cells. We hypothesized that the initial phase of differentiation can be enhanced if the transcriptional activity of master regulators of stemness is suppressed, blocking the formation of functional transcriptomes. However, an obstacle is the lack of an efficient strategy to block protein-protein interactions. In this work, we take advantage of the biochemical property of seventeen kilodalton protein (Skp), a bacterial molecular chaperone that binds directly to sex determining region Y-box 2 (Sox2). The small angle X-ray scattering analyses provided a low resolution model of the complex and suggested that the transactivation domain of Sox2 is probably wrapped in a cleft on Skp trimer. Upon the transduction of Skp into pluripotent cells, the transcriptional activity of Sox2 was inhibited and the expression of Sox2 and octamer-binding transcription factor 4 was reduced, which resulted in the expression of early differentiation markers and appearance of early neuronal and cardiac progenitors. These results suggest that the initial stage of differentiation can be accelerated by inhibiting master transcription factors of stemness. This strategy can possibly be applied to increase the efficiency of stem cell differentiation into various cell types and also provides a clue to understanding the mechanism of early differentiation. PMID:24434556

De, Debojyoti; Jeong, Myong-Ho; Leem, Young-Eun; Svergun, Dmitri I; Wemmer, David E; Kang, Jong-Sun; Kim, Kyeong Kyu; Kim, Sung-Hou

2014-02-01

372

A three stage model for the inner engine of Gamma Ray Burst: Prompt emission and early afterglow  

E-print Network

We propose a new model within the ``Quark-nova'' scenario to interpret the recent observations of early afterglows of long Gamma-Ray Bursts (GRB) with the Swift satellite. This is a three-stage model within the context of a core-collapse supernova. Stage 1 is an accreting (proto-) neutron star leading to a possible delay between the core collapse and the GRB. Stage 2 is an accreting quark-star, generating the prompt GRB. Stage 3, which occurs only if the quark-star collapses to form a black-hole, consists of an accreting black-hole. The jet launched in this accretion process interacts with the ejecta from stage 2, and could generate the flaring activity frequently seen in X-ray afterglows. This model may be able to account for both the energies and the timescales of GRBs, in addition to the newly discovered early X-ray afterglow features.

Jan Staff; Rachid Ouyed; Manjari Bagchi

2006-08-22

373

A Pilot Study of Circulating miRNAs as Potential Biomarkers of Early Stage Breast Cancer  

PubMed Central

Background To date, there are no highly sensitive and specific minimally invasive biomarkers for detection of breast cancer at an early stage. The occurrence of circulating microRNAs (miRNAs) in blood components (including serum and plasma) has been repeatedly observed in cancer patients as well as healthy controls. Because of the significance of miRNA in carcinogenesis, circulating miRNAs in blood may be unique biomarkers for early and minimally invasive diagnosis of human cancers. The objective of this pilot study was to discover a panel of circulating miRNAs as potential novel breast cancer biomarkers. Methodology/Principal Findings Using microarray-based expression profiling followed by Real-Time quantitative Polymerase Cycle Reaction (RT-qPCR) validation, we compared the levels of circulating miRNAs in plasma samples from 20 women with early stage breast cancer (10 Caucasian American (CA) and 10 African American (AA)) and 20 matched healthy controls (10 CAs and 10 AAs). Using the significance level of p<0.05 constrained by at least two-fold expression change as selection criteria, we found that 31 miRNAs were differentially expressed in CA study subjects (17 up and 14 down) and 18 miRNAs were differentially expressed in AA study subjects (9 up and 9 down). Interestingly, only 2 differentially expressed miRNAs overlapped between CA and AA study subjects. Using receiver operational curve (ROC) analysis, we show that not only up-regulated but also down-regulated miRNAs can discriminate patients with breast cancer from healthy controls with reasonable sensitivity and specificity. To further explore the potential roles of these circulating miRNAs in breast carcinogenesis, we applied pathway-based bioinformatics exploratory analysis and predicted a number of significantly enriched pathways which are predicted to be regulated by these circulating miRNAs, most of which are involved in critical cell functions, cancer development and progression. Conclusions Our observations from this pilot study suggest that the altered levels of circulating miRNAs might have great potential to serve as novel, noninvasive biomarkers for early detection of breast cancer. PMID:21060830

Zhao, Hua; Shen, Jie; Medico, Leonard; Wang, Dan; Ambrosone, Christine B.; Liu, Song

2010-01-01

374

Disruption of Smad-dependent signaling for growth of GST-P-positive lesions from the early stage in a rat two-stage hepatocarcinogenesis model  

SciTech Connect

To clarify the involvement of signaling of transforming growth factor (TGF)-{beta} during the hepatocarcinogenesis, the immunohistochemical distribution of related molecules was analyzed in relation with liver cell lesions expressing glutathione S-transferase placental form (GST-P) during liver tumor promotion by fenbendazole, phenobarbital, piperonyl butoxide, or thioacetamide, using rats. Our study focused on early-stage promotion (6 weeks after starting promotion) and late-stage promotion (57 weeks after starting promotion). With regard to Smad-dependent signaling, cytoplasmic accumulation of phosphorylated Smad (phospho-Smad)-2/3 - identified as Smad3 by later immunoblot analysis - increased in the subpopulation of GST-P{sup +} foci, while Smad4, a nuclear transporter of Smad2/3, decreased during early-stage promotion. By late-stage promotion, GST-P{sup +} lesions lacking phospho-Smad2/3 had increased in accordance with lesion development from foci to carcinomas, while Smad4 largely disappeared in most proliferative lesions. With regard to Smad-independent mitogen-activated protein kinases, GST-P{sup +} foci that co-expressed phospho-p38 mitogen-activated protein kinase increased during early-stage promotion; however, p38-downstream phospho-activating transcriptional factor (ATF)-2, ATF3, and phospho-c-Myc, were inversely downregulated without relation to promotion. By late-stage promotion, proliferative lesions downregulated phospho-ATF2 and phospho-c-Myc along with lesion development, as with downregulation of phospho-p38 in all lesions. These results suggest that from the early stages, carcinogenic processes were facilitated by disruption of tumor suppressor functions of Smad-dependent signaling, while Smad-independent activation of p38 was an early-stage phenomenon. GST-P{sup -} foci induced by promotion with agonists of peroxisome proliferator-activated receptor-{alpha} did not change Smad expression, suggesting an aberration in the Smad-dependent signaling prerequisites for induction of GST-P{sup +} proliferative lesions.

Ichimura, Ryohei, E-mail: red0828@hotmail.co.j [Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509 (Japan); Mizukami, Sayaka, E-mail: non_sugar_life@hotmail.co.j [Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509 (Japan); Takahashi, Miwa, E-mail: mtakahashi@nihs.go.j [Division of Pathology, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-8501 (Japan); Taniai, Eriko, E-mail: taniaie@cc.tuat.ac.j [Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509 (Japan); Kemmochi, Sayaka, E-mail: msayaka@cc.tuat.ac.j [Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509 (Japan); Pathogenetic Veterinary Science, United Graduate School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu-shi, Gifu 501-1193 (Japan); Mitsumori, Kunitoshi, E-mail: mitsumor@cc.tuat.ac.j [Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509 (Japan); Shibutani, Makoto, E-mail: mshibuta@cc.tuat.ac.j [Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509 (Japan)

2010-08-01

375

Adsorption-induced restructuring and early stages of carbon-nanotube growth on Ni nanoparticles.  

PubMed

Carbon adsorption on various Ni surfaces is investigated as a function of coverage via a combination of first-principles simulations and field emission microscope experiments. It is found that carbon can be efficiently stored as subsurface carbides, but with different energetics on differently oriented surfaces depending on their compactness and density of adsorption sites. In the resulting morphological reshaping, {113} facets are predicted to grow at the expense of {111} and {100} facets, in excellent agreement with experimental observations. Moreover, at high coverage on the {113} surface the carbon adsorption energy passes through a maximum after which a structural crossover is realized such that carbon atoms tend to ascend to the surface to form one-dimensional chains (which are the precursors of graphitic nanostructures). This rationalizes the experimental observation of an incubation time between carbon storage and the beginning of catalytic growth, and provides insight into the early stages (nucleation mechanism) of carbon nanotubes on Ni nanoparticles. PMID:23169259

Wang, Yuexia; Barcaro, Giovanni; Negreiros, Fabio R; Visart de Bocarmé, Thierry; Moors, Mathieu; Kruse, Norbert; Hou, Marc; Fortunelli, Alessandro

2013-01-01

376

Early-stage chunking of finger tapping sequences by persons who stutter and fluent speakers.  

PubMed

This research note explored the hypothesis that chunking differences underlie the slow finger-tap sequencing performance reported in the literature for persons who stutter (PWS) relative to fluent speakers (PNS). Early-stage chunking was defined as an immediate and spontaneous tendency to organize a long sequence into pauses, for motor planning, and chunks of fluent motor performance. A previously published study in which 12 PWS and 12 matched PNS practised a 10-item finger tapping sequence 30 times was examined. Both groups significantly decreased the duration of between-chunk intervals (BCIs) and within-chunk intervals (WCIs) over practice. PNS had significantly shorter WCIs relative to PWS, but minimal differences between groups were found for the number of, or duration of, BCI. Results imply that sequencing differences found between PNS and PWS may be due to differences in automatizing movements within chunks or retrieving chunks from memory rather than chunking per se. PMID:23237418

Smits-Bandstra, Sarah; De Nil, Luc F

2013-01-01

377

Emission of spherical cesium-bearing particles from an early stage of the Fukushima nuclear accident  

PubMed Central

The Fukushima nuclear accident released radioactive materials into the environment over the entire Northern Hemisphere in March 2011, and the Japanese government is spending large amounts of money to clean up the contaminated residential areas and agricultural fields. However, we still do not know the exact physical and chemical properties of the radioactive materials. This study directly observed spherical Cs-bearing particles emitted during a relatively early stage (March 14–15) of the accident. In contrast to the Cs-bearing radioactive materials that are currently assumed, these particles are larger, contain Fe, Zn, and Cs, and are water insoluble. Our simulation indicates that the spherical Cs-bearing particles mainly fell onto the ground by dry deposition. The finding of the spherical Cs particles will be a key to understand the processes of the accident and to accurately evaluate the health impacts and the residence time in the environment. PMID:23989894

Adachi, Kouji; Kajino, Mizuo; Zaizen, Yuji; Igarashi, Yasuhito

2013-01-01

378

Placental transport of lindane during early and late stages of gestation in rats  

SciTech Connect

Lindane (gamma-isomer of hexachlorocyclohexane, gamma-HCH), an organochlorine pesticide, is widely used as an agricultural pesticide especially in developing countries. Human exposure is likely because of its use in some pharmaceutical preparations and in public health for pest control purpose. It has been detected in human milk and fat samples in India and in many developed countries. The accumulation of lindane over a long period in fat samples and its presence in milk suggests that the human fetus may be exposed to lindane at some time during gestation from the maternal tissue stores. The present study was, therefore, undertaken to determine the placental transfer of lindane in rats during early and late stages of gestation.

Khanna, R.N.; Kunwar, K.; Gupta, R.; Gupta, G.S.D. (Industrial Toxicology Research Centre, Lucknow (India))

1991-10-01

379

Proton-Based Stereotactic Ablative Radiotherapy in Early-Stage Non-Small-Cell Lung Cancer  

PubMed Central

Stereotactic ablative radiotherapy (SABR), a recent implementation in the practice of radiation oncology, has been shown to confer high rates of local control in the treatment of early stage non-small-cell lung cancer (NSCLC). This technique, which involves limited invasive procedures and reduced treatment intervals, offers definitive treatment for patients unable or unwilling to undergo an operation. The use of protons in SABR delivery confers the added physical advantage of normal tissue sparing due to the absence of collateral radiation dose delivered to regions distal to the target. This may translate into clinical benefit and a decreased risk of clinical toxicity in patients with nearby critical structures or limited pulmonary reserve. In this review, we present the rationale for proton-based SABR, principles relating to the delivery and planning of this modality, and a summary of published clinical studies. PMID:25136582

Grant, Jonathan D.; Chang, Joe Y.

2014-01-01

380

Ultrasonic force microscopy for nanomechanical characterization of early and late-stage amyloid-? peptide aggregation  

NASA Astrophysics Data System (ADS)

The aggregation of amyloid-? peptides into protein fibres is one of the main neuropathological features of Alzheimer's disease (AD). While imaging of amyloid-? aggregate morphology in vitro is extremely important for understanding AD pathology and in the development of aggregation inhibitors, unfortunately, potentially highly toxic, early aggregates are difficult to observe by current electron microscopy and atomic force microscopy (AFM) methods, due to low contrast and variability of peptide attachment to the substrate. Here, we use a poly-L-Lysine (PLL) surface that captures all protein components from monomers to fully formed fibres, followed by nanomechanical mapping via ultrasonic force microscopy (UFM), which marries high spatial resolution and nanomechanical contrast with the non-destructive nature of tapping mode AFM. For the main putative AD pathogenic component, A?1-42, the PLL-UFM approach reveals the morphology of oligomers, protofibrils and mature fibres, and finds that a fraction of small oligomers is still present at later stages of fibril assembly.

Tinker-Mill, Claire; Mayes, Jennifer; Allsop, David; Kolosov, Oleg V.

2014-02-01

381

Emission of spherical cesium-bearing particles from an early stage of the Fukushima nuclear accident.  

PubMed

The Fukushima nuclear accident released radioactive materials into the environment over the entire Northern Hemisphere in March 2011, and the Japanese government is spending large amounts of money to clean up the contaminated residential areas and agricultural fields. However, we still do not know the exact physical and chemical properties of the radioactive materials. This study directly observed spherical Cs-bearing particles emitted during a relatively early stage (March 14-15) of the accident. In contrast to the Cs-bearing radioactive materials that are currently assumed, these particles are larger, contain Fe, Zn, and Cs, and are water insoluble. Our simulation indicates that the spherical Cs-bearing particles mainly fell onto the ground by dry deposition. The finding of the spherical Cs particles will be a key to understand the processes of the accident and to accurately evaluate the health impacts and the residence time in the environment. PMID:23989894

Adachi, Kouji; Kajino, Mizuo; Zaizen, Yuji; Igarashi, Yasuhito

2013-01-01

382

Early stage second-language learning improves executive control: Evidence from ERP.  

PubMed

A growing body of research has reported a bilingual advantage in performance on executive control tasks, but it is not known at what point in emerging bilingualism these advantages first appear. The present study investigated the effect of early stage second-language training on executive control. Monolingual English-speaking students were tested on a go-nogo task, sentence judgment task, and verbal fluency, before and after 6months of Spanish instruction. The training group (n=25) consisted of students enrolled in introductory Spanish and the control group (n=30) consisted of students enrolled in introductory Psychology. After training, the Spanish group showed larger P3 amplitude on the go-nogo task and smaller P600 amplitude on the judgment task, indicating enhanced performance, with no changes for the control group and no differences between groups on behavioral measures. Results are discussed in terms of neural changes underlying executive control after brief second-language learning. PMID:25463819

Sullivan, Margot D; Janus, Monika; Moreno, Sylvain; Astheimer, Lori; Bialystok, Ellen

2014-11-01

383

An Analysis of Risk and Function Information in Early Stage Design  

NASA Technical Reports Server (NTRS)

The concept of function offers a high potential for thinking and reasoning about designs as well as providing a common thread for relating together other design information. This paper focuses specifically on the relation between function and risk by examining how this information is addressed for a design team conducting early stage design for space missions. Risk information is decomposed into a set of key attributes which are then used to scrutinize the risk information using three approaches from the pragmatics sub-field of linguistics: i) Gricean, ii) Relevance Theory, and Functional Analysis. Results of this linguistics-based approach descriptively account for the context of designer communication with respect to function and risk, and offer prescriptive guidelines for improving designer communication.

Barrientos, Francesca; Tumer, Irem; Grantham, Katie; VanWie, Michael; Stone, Robert

2005-01-01

384

Late-Stage Fluvial Erosion in a Changing Climate on Early Mars  

NASA Astrophysics Data System (ADS)

The decline of heavy bombardment in the solar system coincided with incision of many branching fluvial valleys in the martian highlands. However, these valley networks are underdeveloped relative to typical terrestrial networks, suggesting that valley incision was geologically brief or slow on Mars. Most previous studies have attributed the end of martian fluvial erosion to a monotonic decline of the atmosphere and climate around the Noachian/Hesperian transition. Identification of fluvial valleys on some younger surfaces, including Hesperian volcanoes, and the occurrence of morphologically pristine and degraded reaches in the same valley networks challenged the simplicity of this model. More recently, fluvial valleys and deposits have been recognized on a variety of Hesperian surfaces, including the plateau around Valles Marineris, certain impact craters, and the crustal dichotomy boundary scarp. The extent to which this late-stage erosion represents localized event floods or more widely distributed precipitation and runoff remains to be determined. To evaluate whether Hesperian resurfacing processes were concurrent with (and may have caused) late-stage fluvial erosion, we are identifying any geologically rare or long-lived events that occurred between significant resurfacing events and fluvial erosion of those surfaces. In a variety of locations, we have identified small primary craters that formed between local resurfacing and fluvial dissection of those surfaces, suggesting a gap in time between resurfacing and dissection. These small, otherwise fresh craters have rims or ejecta that were incised by late-stage flows. In other cases, thick stratified deposits accumulated on Hesperian surfaces, and those deposits were later dissected by running water. We also found that highland intercrater plains generally have Early to mid-Hesperian crater populations at diameters less than about 4 km. All smaller primary and secondary craters from the Noachian Period were eradicated. These observations suggest the following geomorphic history. 1) Crater degradation and intercrater resurfacing extended into the Early Hesperian Epoch, but perhaps at a declining rate relative to the Noachian Period. 2) Most of the relict valleys formed as crater degradation declined and intercrater geomorphic surfaces began to stabilize, late in the Noachian or early in the Hesperian Period. 3) Impact cratering, volcanism, tectonism, and wind continued to modify the martian surface during the Hesperian Period. Older valley networks experienced some wall retreat and infilling, forming the classic flat-floored morphology. 4) In one or more intervals during the Late Hesperian or Early Amazonian Epochs, many older valleys reactivated, and some new ones formed on Hesperian surfaces. Late-stage erosion was most effective on steep, high-relief slopes, including Late Noachian and Hesperian crater walls, as well as tectonic scarps. In ongoing work, identifying clear stratigraphic relationships between older valleys, interposed geologic features, and younger valleys is key to determining the number and relative ages of erosional events in the martian highlands.

Irwin, R. P.; Matsubara, Y.

2013-12-01

385

Accelerated partial breast irradiation for early-stage breast cancer: controversies and current indications for use.  

PubMed

Radiation therapy options for early-stage breast cancer have evolved during the past 40 years. Several choices are currently available to certain patient subsets that allow radiation oncologists to individualize care. Multiple phase II and several phase III trials have been published that support the safety and efficacy of accelerated partial breast irradiation (APBI) as part of breast conservation in selected patients. In contrast, a recent large retrospective analysis of patients aged 67 or older who received brachytherapy for APBI has raised concerns about its effectiveness. As the radiation community awaits results from NSABP B-39/RTOG 0413, the largest randomized trial of whole breast radiation therapy (WBRT) versus APBI, to provide more conclusive data, many academic and private radiation oncology practices are utilizing APBI off-protocol to treat early-stage breast cancer patients. Because of this, the American Society for Radiation Oncology (ASTRO) published a consensus statement in 2009 to aid in proper patient selection (Table 1). Until more definitive data is garnered, we advocate strict adherence to these selection criteria to ensure optimal outcomes. Specifically, we caution against the use of APBI in lymph node-positive disease outside of a clinical trial. There is a paucity of comparative data to guide oncologists in selection of the best APBI delivery method. The current NSABP B-39/RTOG 0413 trial allows any of the three most common forms of delivery to be utilized (multicatheter interstitial brachytherapy, balloon intracavitary brachytherapy, and external beam 3D conformal therapy) and will be instrumental to compare outcome differences between these methods. PMID:23179757

Klepczyk, Lisa C; Keene, Kimberly S; De Los Santos, Jennifer F

2013-03-01

386

Electrolyte-carbohydrate beverage prevents water loss in the early stage of high altitude training.  

PubMed

To prevent water loss in the early stage of high altitude training, we focused on the effect of electrolyte-carbohydrate beverage (EC). Subjects were 16 male university students who belonged to a ski club. They had ski training at an altitude of 1,800 m. The water (WT) group drank only water, and the EC group drank only an electrolyte-carbohydrate beverage. They arrived at the training site in the late afternoon. The study started at 7 pm on the day of arrival and continued until noon of the 4(th) day. In the first 12 hours, 1 L of beverages were given. On the second and third days, 2.5 L of beverages were given. All subjects ate the same meals. Each morning while in fasting condition, subjects were weighed and blood was withdrawn for various parameters (hemoglobin, hematocrit, sodium, potassium and aldosterone). Urine was collected at 12 hour intervals for a total 60 hours (5 times). The urine volume, gravity, sodium and potassium concentrations were measured. Peripheral oxygen saturation and heart rate were measured during sleep with a pulse oximeter. Liquid intakes in both groups were similar, hence the electrolytes intake was higher in the EC group than in the WT group. The total urine volume was lower in the EC group than in the WT group, respectively (p<0.05). Plasma volume decreased in the WT group and increased in the EC group but a significant difference was not observed in the final value. Aldosterone concentration tended to be less in the EC group than in the WT group. Electrolyte-carbohydrate beverage in the early stage of high altitude training may be effective in decreasing urinary output and preventing loss of blood plasma volume. PMID:22449998

Yanagisawa, Kae; Ito, Osamu; Nagai, Satsuki; Onishi, Shohei

2012-01-01

387

Modeling screening, prevention, and delaying of Alzheimer's disease: an early-stage decision analytic model  

PubMed Central

Background Alzheimer's Disease (AD) affects a growing proportion of the population each year. Novel therapies on the horizon may slow the progress of AD symptoms and avoid cases altogether. Initiating treatment for the underlying pathology of AD would ideally be based on biomarker screening tools identifying pre-symptomatic individuals. Early-stage modeling provides estimates of potential outcomes and informs policy development. Methods A time-to-event (TTE) simulation provided estimates of screening asymptomatic patients in the general population age ?55 and treatment impact on the number of patients reaching AD. Patients were followed from AD screen until all-cause death. Baseline sensitivity and specificity were 0.87 and 0.78, with treatment on positive screen. Treatment slowed progression by 50%. Events were scheduled using literature-based age-dependent incidences of AD and death. Results The base case results indicated increased AD free years (AD-FYs) through delays in onset and a reduction of 20 AD cases per 1000 screened individuals. Patients completely avoiding AD accounted for 61% of the incremental AD-FYs gained. Total years of treatment per 1000 screened patients was 2,611. The number-needed-to-screen was 51 and the number-needed-to-treat was 12 to avoid one case of AD. One-way sensitivity analysis indicated that duration of screening sensitivity and rescreen interval impact AD-FYs the most. A two-way sensitivity analysis found that for a test with an extended duration of sensitivity (15 years) the number of AD cases avoided was 6,000-7,000 cases for a test with higher sensitivity and specificity (0.90,0.90). Conclusions This study yielded valuable parameter range estimates at an early stage in the study of screening for AD. Analysis identified duration of screening sensitivity as a key variable that may be unavailable from clinical trials. PMID:20433705

2010-01-01

388

Stereotactic Ablative Radiotherapy: A Potentially Curable Approach to Early-Stage Multiple Primary Lung Cancer  

PubMed Central

BACKGROUND Surgical resection has been the standard treatment for early-stage multiple primary lung cancer (MPLC). However, a significant proportion of patients with MPLC cannot undergo surgery. We explored here the role of stereotactic ablative radiotherapy (SABR) for patients with MPLC. METHODS We reviewed MPLC cases treated with SABR (50 Gy in 4 fractions or 70 Gy in 10 fractions) for the second tumor. Four-dimensional CT–based planning/volumetric image-guided treatment was used for all patients. Treatment outcomes/toxicities were analyzed. RESULTS For the 101 patients treated with SABR, at a median follow-up interval of 36 months and median overall survival of 46 months, 2-year and 4-year in-field local control rates were 97.4% and 95.7%. 2- and 4-year rates of overall survival (OS) were 73.2% and 47.5% and progression-free survival (PFS) were 67.0% and 58.0%. Patients with metachronous tumors had higher OS and PFS than did patients with synchronous tumors (2-year OS 80.6% metachronous vs. 61.5% synchronous; 4-year OS 52.7% vs. 39.7%; p=0.047; 2-year PFS 84.7% vs. 49.4%; 4-year PFS 75.6% vs. 30.4%; p=0.0001). For patients whose index tumor was treated with surgery or SABR, the incidence of grade ?3 radiation pneumonitis was 3% (2/71), but this increased to 17% (5/30) for patients whose index tumor was treated with conventional radiotherapy. Other grade ?3 toxicities included grade 3 chest wall pain (3/101, 3%) and grade 3 skin toxicity (1/101, 1%). CONCLUSIONS SABR achieves promising long- term tumor control, survival and could be a potential curative treatment of early-stage MPLC. PMID:23798353

Chang, Joe Y.; Liu, Yung-Hsien; Zhu, Zhengfei; Welsh, James W.; Gomez, Daniel R.; Komaki, Ritsuko; Roth, Jack A.; Swisher, Stephen G.

2013-01-01

389

Regenerative Therapeutic Potential of Adipose Stromal Cells in Early Stage Diabetic Retinopathy  

PubMed Central

Diabetic retinopathy (DR) is the leading cause of blindness in working-age adults. Early stage DR involves inflammation, vascular leakage, apoptosis of vascular cells and neurodegeneration. In this study, we hypothesized that cells derived from the stromal fraction of adipose tissue (ASC) could therapeutically rescue early stage DR features. Streptozotocin (STZ) induced diabetic athymic nude rats received single intravitreal injection of human ASC into one eye and saline into the other eye. Two months post onset of diabetes, administration of ASC significantly improved “b” wave amplitude (as measured by electroretinogram) within 1–3 weeks of injection compared to saline treated diabetic eyes. Subsequently, retinal histopathological evaluation revealed a significant decrease in vascular leakage and apoptotic cells around the retinal vessels in the diabetic eyes that received ASC compared to the eyes that received saline injection. In addition, molecular analyses have shown down-regulation in inflammatory gene expression in diabetic retina that received ASC compared to eyes that received saline. Interestingly, ASC were found to be localized near retinal vessels at higher densities than seen in age matched non-diabetic retina that received ASC. In vitro, ASC displayed sustained proliferation and decreased apoptosis under hyperglycemic stress. In addition, ASC in co-culture with retinal endothelial cells enhance endothelial survival and collaborate to form vascular networks. Taken together, our findings suggest that ASC are able to rescue the neural retina from hyperglycemia-induced degeneration, resulting in importantly improved visual function. Our pre-clinical studies support the translational development of adipose stem cell-based therapy for DR to address both retinal capillary and neurodegeneration. PMID:24416262

Rajashekhar, Gangaraju; Ramadan, Ahmed; Abburi, Chandrika; Callaghan, Breedge; Traktuev, Dmitry O.; Evans-Molina, Carmella; Maturi, Raj; Harris, Alon; Kern, Timothy S.; March, Keith L.

2014-01-01

390

Comparing stochastic differential equations and agent-based modelling and simulation for early-stage cancer.  

PubMed

There is great potential to be explored regarding the use of agent-based modelling and simulation as an alternative paradigm to investigate early-stage cancer interactions with the immune system. It does not suffer from some limitations of ordinary differential equation models, such as the lack of stochasticity, representation of individual behaviours rather than aggregates and individual memory. In this paper we investigate the potential contribution of agent-based modelling and simulation when contrasted with stochastic versions of ODE models using early-stage cancer examples. We seek answers to the following questions: (1) Does this new stochastic formulation produce similar results to the agent-based version? (2) Can these methods be used interchangeably? (3) Do agent-based models outcomes reveal any benefit when compared to the Gillespie results? To answer these research questions we investigate three well-established mathematical models describing interactions between tumour cells and immune elements. These case studies were re-conceptualised under an agent-based perspective and also converted to the Gillespie algorithm formulation. Our interest in this work, therefore, is to establish a methodological discussion regarding the usability of different simulation approaches, rather than provide further biological insights into the investigated case studies. Our results show that it is possible to obtain equivalent models that implement the same mechanisms; however, the incapacity of the Gillespie algorithm to retain individual memory of past events affects the similarity of some results. Furthermore, the emergent behaviour of ABMS produces extra patters of behaviour in the system, which was not obtained by the Gillespie algorithm. PMID:24752131

Figueredo, Grazziela P; Siebers, Peer-Olaf; Owen, Markus R; Reps, Jenna; Aickelin, Uwe

2014-01-01

391

Reproductive outcomes after laparoscopic radical trachelectomy for early-stage cervical cancer  

PubMed Central

Objective The objective of this study was to estimate the reproductive outcome of young women with early-stage cervical cancer who underwent fertility-sparing laparoscopic radical trachelectomy (LRT). Methods We performed a retrospective review of the medical records of patients with early-stage cervical cancer who underwent LRT. Clinicopathological data were obtained from patient medical records, and reproductive outcome data were obtained from patient medical records and telephone interviews. Results Fifty-five patients who underwent successful LRT were included in this study. The median age of patients was 32 years (range, 22 to 40 years), and the median follow-up time after LRT was 37 months (range, 3 to 105 months). Menstruation resumed in all patients after LRT, with fifty patients (90.9%) and five patients (9.1%) reporting regular and irregular menstruation, respectively. Six patients (10.9%) presented with cervical stenosis, which was manifested by regular but decreased menstrual flow and newly-developed dysmenorrhea. These patients underwent cervical cannulation and dilatation. Eighteen patients (32.7%) attempted to conceive, with six out of 18 patients receiving fertility treatments. Fourteen pregnancies (i.e., four missed abortions, six preterm births and four full-term births) occurred in 10 patients after LRT. Nine out of 10 patients gave birth to 10 healthy babies. The pregnancy rate after LRT was 55.6% (10/18). The spontaneous abortion rate and live birth rate were 28.6% (4/14) and 71.4% (10/14), respectively. The preterm birth rate was 60% (6/10). Conclusion Pregnancy and live birth rates after LRT were promising; however, the preterm birth rate was relatively high. Cervical stenosis also occurred in a small percentage of patients. PMID:24459575

Park, Jeong-Yeol; Kim, Dae-Yeon; Suh, Dae-Shik; Kim, Jong-Hyeok; Kim, Yong-Man; Kim, Young-Tak

2014-01-01

392

Radiofrequency ablation compared to resection in early-stage hepatocellular carcinoma  

PubMed Central

Objectives: This study aimed to compare survival outcomes after hepatic resection (HR) and radiofrequency ablation (RFA) in early-stage hepatocellular carcinoma (HCC) at a Western hepatobiliary centre. Methods: Demographic details, clinicopathologic tumour characteristics and survival outcomes were compared among non-transplant candidate patients undergoing HR (n= 50) and RFA (n= 60) for early-stage HCC during 2001–2011. Results: Patients who underwent HR had larger tumours, a longer length of stay and a higher rate of postoperative complications. After a median follow-up of 29 months, there were no significant differences between the treatment groups in 1-, 3- and 5-year overall survival (OS) [RFA group: 86%, 50%, 35%, respectively; HR group: 88%, 68%, 47%, respectively (P= 0.222)] or disease-free survival (DFS) [RFA group: 68%, 42%, 28%, respectively; HR group: 66%, 42%, 34%, respectively (P= 0.823)]. The 58 patients who underwent RFA demonstrated ablation success on follow-up computed tomography at 3 months. Of these, 96.5% of patients showed sustained ablation success over the entire follow-up period. In a subgroup analysis of patients with tumours measuring 2–5 cm, no differences in OS or DFS emerged between the HR and RFA groups. Similarly, no significant differences in outcomes in patients with Child–Pugh class A cirrhosis were seen between the RFA and HR groups. Conclusions: Radiofrequency ablation is comparable with HR in terms of OS and DFS. It is a reasonable alternative as a first-line treatment for HCC in well-selected patients who are not candidates for transplant. PMID:23374361

Tohme, Samer; Geller, David A.; Cardinal, Jon S.; Chen, Hui-Wei; Packiam, Vignesh; Reddy, Srinevas; Steel, Jennifer; Marsh, James W.; Tsung, Allan

2013-01-01

393

Population genomics of a symbiont in the early stages of a pest invasion.  

PubMed

Invasive species often depend on microbial symbionts, but few studies have examined the evolutionary dynamics of symbionts during the early stages of an invasion. The insect Megacopta cribraria and its bacterial nutritional symbiont Candidatus Ishikawaella capsulata invaded the southeastern US in 2009. While M. cribraria was initially discovered on wild kudzu plants, it was found as a pest on soybeans within 1 year of infestation. Because prior research suggests Ishikawaella confers the pest status--that is, the ability to thrive on soybeans--in some Megacopta species, we performed a genomic study on Ishikawaella from US. Megacopta cribraria populations to understand the role of the symbiont in driving host plant preferences. We included Ishikawaella samples collected in the first days of the invasion in 2009 and from 23 locations across the insect's 2011 US range. The 0.75 Mb symbiont genome revealed only 47 fixed differences from the pest-conferring Ishikawaella in Japan, with only one amino acid change in a nutrition-provisioning gene. This similarity, along with a lack of fixed substitutions in the US symbiont population, indicates that Ishikawella likely arrived in the US capable of being a soybean pest. Analyses of allele frequency changes between 2009 and 2011 uncover signatures of both positive and negative selection and suggest that symbionts on soybeans and kudzu experience differential selection for genes related to nutrient provisioning. Our data reveal the evolutionary trajectory of an important insect-bacteria symbiosis in the early stages of an invasion, highlighting the role microbial symbionts may play in the spread of invasive species. PMID:23841878

Brown, Amanda M V; Huynh, Lynn Y; Bolender, Caitlin M; Nelson, Kelly G; McCutcheon, John P

2014-03-01

394

Redox Protein Expression Predicts Radiotherapeutic Response in Early-Stage Invasive Breast Cancer Patients  

SciTech Connect

Purpose: Early-stage invasive breast cancer patients have commonly undergone breast-conserving surgery and radiotherapy. In a large majority of these patients, the treatment is effective; however, a proportion will develop local recurrence. Deregulated redox systems provide cancer cells protection from increased oxidative stress, such as that induced by ionizing radiation. Therefore, the expression of redox proteins was examined in tumor specimens from this defined cohort to determine whether such expression could predict response. Methods and Materials: The nuclear and cytoplasmic expression of nine redox proteins (glutathione, glutathione reductase, glutaredoxin, glutathione peroxidase 1, 3, and 4, and glutathione S-transferase-{theta}, -{pi}, and -{alpha}) was assessed using conventional immunohistochemistry on a tissue microarray of 224 tumors. Results: A high cytoplasmic expression of glutathione S-transferase-{theta} significantly correlated with a greater risk of local recurrence (p = .008) and, when combined with a low nuclear expression (p = .009), became an independent predictive factor (p = .002) for local recurrence. High cytoplasmic expression of glutathione S-transferase-{theta} also correlated with a worse overall survival (p = .009). Low nuclear and cytoplasmic expression of glutathione peroxidase 3 (p = .002) correlated with a greater risk of local recurrence and was an independent predictive factor (p = .005). These proteins did not correlate with tumor grade, suggesting their function might be specific to the regulation of oxidative stress rather than alterations of tumor phenotype. Only nuclear (p = .005) and cytoplasmic (p = .001) expression of glutathione peroxidase 4 correlated with the tumor grade. Conclusions: Our results support the use of redox protein expression, namely glutathione S-transferase-{theta} and glutathione peroxidase 3, to predict the response to radiotherapy in early-stage breast cancer patients. If incorporated into routine diagnostic tests, they have the potential to aid clinicians in their stratification of patients into more tailored treatment regimens. Future targeted therapies to these systems might improve the efficacy of reactive oxygen species-inducing therapies, such as radiotherapy.

Woolston, Caroline M. [Division of Clinical Oncology, University of Nottingham School of Molecular Medical Sciences, Nottingham (United Kingdom); Al-Attar, Ahmad [Department of Clinical Oncology, Nottingham University Hospitals National Health Service Trust, City Hospital, Nottingham (United Kingdom); Storr, Sarah J. [Division of Clinical Oncology, University of Nottingham School of Molecular Medical Sciences, Nottingham (United Kingdom); Ellis, Ian O. [Division of Histopathology, University of Nottingham School of Molecular Medical Sciences, Nottingham (United Kingdom); Morgan, David A.L. [Department of Clinical Oncology, Nottingham University Hospitals National Health Service Trust, City Hospital, Nottingham (United Kingdom); Martin, Stewart G., E-mail: stewart.martin@nottingham.ac.u [Division of Clinical Oncology, University of Nottingham School of Molecular Medical Sciences, Nottingham (United Kingdom)

2011-04-01

395

Similarity Ratio Analysis for Early Stage Fault Detection with Optical Emission Spectrometer in Plasma Etching Process  

PubMed Central

A Similarity Ratio Analysis (SRA) method is proposed for early-stage Fault Detection (FD) in plasma etching processes using real-time Optical Emission Spectrometer (OES) data as input. The SRA method can help to realise a highly precise control system by detecting abnormal etch-rate faults in real-time during an etching process. The method processes spectrum scans at successive time points and uses a windowing mechanism over the time series to alleviate problems with timing uncertainties due to process shift from one process run to another. A SRA library is first built to capture features of a healthy etching process. By comparing with the SRA library, a Similarity Ratio (SR) statistic is then calculated for each spectrum scan as the monitored process progresses. A fault detection mechanism, named 3-Warning-1-Alarm (3W1A), takes the SR values as inputs and triggers a system alarm when certain conditions are satisfied. This design reduces the chance of false alarm, and provides a reliable fault reporting service. The SRA method is demonstrated on a real semiconductor manufacturing dataset. The effectiveness of SRA-based fault detection is evaluated using a time-series SR test and also using a post-process SR test. The time-series SR provides an early-stage fault detection service, so less energy and materials will be wasted by faulty processing. The post-process SR provides a fault detection service with higher reliability than the time-series SR, but with fault testing conducted only after each process run completes. PMID:24755865

Yang, Jie; McArdle, Conor; Daniels, Stephen

2014-01-01

396

Proliferation of endogenous retroviruses in the early stages of a host germ line invasion.  

PubMed

Endogenous retroviruses (ERVs) comprise 8% of the human genome and are common in all vertebrate genomes. The only retrovirus known to be currently transitioning from exogenous to endogenous form is the koala retrovirus (KoRV), making koalas (Phascolarctos cinereus) ideal for examining the early stages of retroviral endogenization. To distinguish endogenous from exogenous KoRV proviruses, we isolated koala genomic regions flanking KoRV integration sites. In three wild southern Australian koalas, there were fewer KoRV loci than in three captive Queensland koalas, consistent with reports that southern Australian koalas carry fewer KoRVs. Of 39 distinct KoRV proviral loci examined in a sire-dam-progeny triad, all proved to be vertically transmitted and endogenous; none was exogenous. Of the 39 endogenous KoRVs (enKoRVs), only one was present in the genomes of both the sire and the dam, suggesting that, at this early stage in the retroviral invasion of a host germ line, very large numbers of ERVs have proliferated at very low frequencies in the koala population. Sequence divergence between the 5'- and 3'-long terminal repeats (LTRs) of a provirus can be used as a molecular clock. Within each of ten enKoRVs, the 5'-LTR sequence was identical to the 3'-LTR sequence, suggesting a maximum age for enKoRV invasion of the koala germ line of approximately 22,200-49,900 years ago, although a much younger age is possible. Across the ten proviruses, seven LTR haplotypes were detected, indicating that at least seven different retroviral sequences had entered the koala germ line. PMID:25261407

Ishida, Yasuko; Zhao, Kai; Greenwood, Alex D; Roca, Alfred L

2015-01-01

397

Distinguishing Benign Thymic Lesions from Early Stage Thymic Malignancies on Computed Tomography  

PubMed Central

Introduction The increasing use of computed tomography (CT) has led to more-frequent identification of asymptomatic lesions in the anterior mediastinum. The purpose of this study is to identify CT features that distinguish benign thymic lesions from early stage malignant thymic neoplasms. Methods We retrospectively reviewed preoperative CT imaging for 66 patients who had undergone thymectomy for benign thymic lesions or early stage malignant thymic neoplasms. All variables with a p-value <0.2 on univariate logistic regression analysis were evaluated by multivariate analysis. Stepwise selection was performed, and variables with a p-value <0.05 were retained in the final model. Results Thirty-eight malignant (58%) and 28 benign thymic lesions (42%) were included. Patients with benign thymic tumors were significantly younger (median age, 49.5 years) than patients with malignant tumors (60.0 years; p=0.007). Malignant tumors were larger in short-axis dimension (p=0.028) and more frequently in a non-midline location in the anterior mediastinum (p=0.029). Intralesional fat was seen exclusively in benign masses (p=0.002). Seven benign tumors (25%) and 1 malignant tumor (2.6%) had a triangular thymic shape (p=0.023). In multivariate analysis, lower age, smaller short-axis dimension, and lack of infiltration of the mediastinal fat were significant independent predictors of benign pathologic results. Conclusion Intralesional fat, midline location, and triangular thymic shape are more frequently found in benign thymic lesions. Lack of infiltration of the mediastinal fat, younger patient age, and smaller size are independent predictors of benign thymic lesions. These features may help characterize thymic masses as benign and avert potentially unnecessary invasive diagnostic procedures. PMID:23608816

McErlean, Aoife; Huang, James; Zabor, Emily C.; Moskowitz, Chaya S.; Ginsberg, Michelle S.

2014-01-01

398

Early stage carcinoma of oral tongue: prognostic factors for local control and survival.  

PubMed

The purpose of this study was to assess prognostic factors, treatment outcomes and patterns of relapse in patients with early stage (T1-2 N0) squamous cell carcinoma of oral tongue treated primarily by surgery. The medical records of all patients with early stage (T1-2 N0) oral tongue cancer, radically treated at King Faisal Specialist Hospital and Research Center between January 1980 and December 1997, were reviewed. Eighty-five patients were identified for analysis, 38 male and 47 female. With a median follow-up for surviving patients of 64 months, 5-year actuarial overall, disease-specific (DSS), and relapse-free survival (RFS) were 71, 75, and 63%, respectively. Univariate analysis for DSS showed survival advantage for patients with tumor thickness (TT) of < or =10 mm (P=0.0002) and distance from resection margin (DFRM) of > 5 mm (P=0.005). The effect of TT of < or =10 mm was maintained (P=0.001) on multivariate analysis. Higher RFS was observed with TT of < or =10 mm (P=0.0002), DFRM of > 5 mm (P=0.0002) and DFRM of >10 mm (P=0.007). On multivariate analysis higher RFS was also found for TT < or =10 mm (P=0.01) and DFRM >5 mm (P=0.01). Salvage of local tongue recurrence was higher than neck node failure, with 5-year DSS of 71 and 19%, respectively (P=0.007). Time interval for recurrence showed no significant impact on outcome. In T1-2 N0 oral tongue cancer, TT, and DFRM are significant prognostic factors for both local control and survival. Neck node recurrence is associated with poor prognosis and low salvage rate. PMID:11036243

Al-Rajhi, N; Khafaga, Y; El-Husseiny, J; Saleem, M; Mourad, W; Al-Otieschan, A; Al-Amro, A

2000-11-01

399

Early Stage Biomineralization in the Periostracum of the ‘Living Fossil’ Bivalve Neotrigonia  

PubMed Central

A detailed investigation of the shell formation of the palaeoheterodont ‘living fossil’ Neotrigonia concentrated on the timing and manufacture of the calcified ‘bosses’ which stud the outside of all trigonioid bivalves (extant and fossil) has been conducted. Electron microscopy and optical microscopy revealed that Neotrigonia spp. have a spiral-shaped periostracal groove. The periostracum itself is secreted by the basal cell, as a thin dark pellicle, becoming progressively transformed into a thin dark layer by additions of secretions from the internal outer mantle fold. Later, intense secretion of the internal surface of the outer mantle fold forms a translucent layer, which becomes transformed by tanning into a dark layer. The initiation of calcified bosses occurred at a very early stage of periostracum formation, deep within the periostracal groove immediately below the initialmost dark layer. At this stage, they consist of a series of polycyclically twinned crystals. The bosses grow as the periostracum traverse through the periostracal groove, in coordination with the thickening of the dark periostracal layer and until, upon reaching the mantle edge, they impinge upon each other and become transformed into large prisms separated by dark periostracal walls. In conclusion, the initial bosses and the external part of the prismatic layer are fully intraperiostracal. With later growth, the prisms transform into fibrous aggregates, although the details of the process are unknown. This reinforces the relationships with other groups that have the ability to form intraperiostracal calcifications, for example the unionoids with which the trigonioids form the clade Paleoheterodonta. The presence of similar structures in anomalodesmatans and other euheterodonts raises the question of whether this indicates a relationship or represents a convergence. The identification of very early calcification within an organic sheet has interesting implications for our understanding of how shells may have evolved. PMID:24587202

Checa, Antonio G.; Salas, Carmen; Harper, Elizabeth M.; Bueno-Pérez, Juan de Dios

2014-01-01

400

Attentional modulations of the early and later stages of the neural processing of visual completion  

PubMed Central

The brain effortlessly recognizes objects even when the visual information belonging to an object is widely separated, as well demonstrated by the Kanizsa-type illusory contours (ICs), in which a contour is perceived despite the fragments of the contour being separated by gaps. Such large-range visual completion has long been thought to be preattentive, whereas its dependence on top-down influences remains unclear. Here, we report separate modulations by spatial attention and task relevance on the neural activities in response to the ICs. IC-sensitive event-related potentials that were localized to the lateral occipital cortex were modulated by spatial attention at an early processing stage (130–166?ms after stimulus onset) and modulated by task relevance at a later processing stage (234–290?ms). These results not only demonstrate top-down attentional influences on the neural processing of ICs but also elucidate the characteristics of the attentional modulations that occur in different phases of IC processing. PMID:25666450

Wu, Xiang; Zhou, Liang; Qian, Cheng; Gan, Lingyu; Zhang, Daren

2015-01-01

401

Hematopoietic cell crisis: An early stage of evolving myeloid leukemia following radiation exposure  

SciTech Connect

Under select radiological conditions, chronic radiation exposure elicits a high incidence of myeloproliferative disease, principally myeloid leukemia (ML), in beagles. Previously we demonstrated that for full ML expression, a four-stage preclinical sequence is required, namely (1) suppression, (2) recovery, (3) accommodation, and (4) preleukemic transition. Within this pathological sequence, a critical early event has been identified as the acquisition of radioresistance by hematopoietic progenitors that serves to mediate a newfound regenerative hematopoietic capacity. As such, this event sets the stage'' for preleukemic progression by initiating progression from preclinical phase 1 to 2. Due to the nature of target cell suppression, the induction of crisis, and the outgrowth of progenitors with altered phenotypes, this preleukemic event resembles the immortalization'' step of the in vitro transformation sequence following induction with either physical and chemical carcinogens. The radiological, temporal, and biological dictates governing this event have been extensively evaluated and will be discussed in light of their role in the induction and progression of chronic radiation leukemia. 35 refs., 2 tabs.

Seed, T.M.

1990-01-01

402

Lysine-specific demethylase 1 expression in zebrafish during the early stages of neuronal development.  

PubMed

Lysine-specific demethylase 1 (Lsd1) is associated with transcriptional coregulation via the modulation of histone methylation. The expression pattern and function of zebrafish Lsd1 has not, however, been studied. Here, we describe the pattern of zebrafish Lsd1 expression during different development stages. In the zebrafish embryo, lsd1 mRNA was present during the early cleavage stage, indicating that maternally derived Lsd1 protein is involved in embryonic patterning. During embryogenesis from 0 to 48 hours post-fertilization (hpf), the expression of lsd1 mRNA in the embryo was ubiquitous before 12 hpf and then became restricted to the anterior of the embryo (particularly in the brain) from 24 hpf to 72 hpf. Inhibition of Lsd1 activity (by exposure to tranylcypromine) or knockdown of lsd1 expression (by morpholino antisense oligonucleotide injection) led to the loss of cells in the brain and to a dramatic downregulation of neural genes, including gad65, gad75, and reelin, but not hey1. These findings indicate an important role of Lsd1 during nervous system development in zebrafish. PMID:25337119

Li, Aihong; Sun, Yong; Dou, Changming; Chen, Jixian; Zhang, Jie

2012-12-01

403

Attentional modulations of the early and later stages of the neural processing of visual completion.  

PubMed

The brain effortlessly recognizes objects even when the visual information belonging to an object is widely separated, as well demonstrated by the Kanizsa-type illusory contours (ICs), in which a contour is perceived despite the fragments of the contour being separated by gaps. Such large-range visual completion has long been thought to be preattentive, whereas its dependence on top-down influences remains unclear. Here, we report separate modulations by spatial attention and task relevance on the neural activities in response to the ICs. IC-sensitive event-related potentials that were localized to the lateral occipital cortex were modulated by spatial attention at an early processing stage (130-166?ms after stimulus onset) and modulated by task relevance at a later processing stage (234-290?ms). These results not only demonstrate top-down attentional influences on the neural processing of ICs but also elucidate the characteristics of the attentional modulations that occur in different phases of IC processing. PMID:25666450

Wu, Xiang; Zhou, Liang; Qian, Cheng; Gan, Lingyu; Zhang, Daren

2015-01-01

404

Epigenetic status of LINE-1 predicts clinical outcome in early-stage rectal cancer  

PubMed Central

Background: We evaluated the clinical prognostic value of methylation of two non-coding repeat sequences, long interspersed element 1 (LINE-1) and Alu, in rectal tumour tissues. In addition to DNA methylation, expression of histone modifications H3K27me3 and H3K9Ac was studied in this patient cohort. Methods: LINE-1 and Alu methylation were assessed in DNA extracted from formalin-fixed paraffin-embedded tissues. A pilot (30 tumour and 25 normal tissues) and validation study (189 tumour and 53 normal tissues) were performed. Histone modifications H3K27me3 and H3K9Ac were immunohistochemically stained on tissue microarrays of the study cohort. Results: In early-stage rectal cancer (stage I-II), hypomethylation of LINE-1 was an independent clinical prognostic factor, showing shorter patient survival (P=0.014; HR: 4.6) and a higher chance of tumour recurrence (P=0.001; HR: 9.6). Alu methylation did not show any significant correlation with clinical parameters, suggesting an active role of LINE-1 in tumour development. Expression of H3K27me3 (silencing gene expression) and H3K9Ac (activating gene expression) in relation to methylation status of LINE-1 and Alu supported this specific role of LINE-1 methylation. Conclusion: The epigenetic status of LINE-1, but not of Alu, is prognostic in rectal cancer, indicating an active role for LINE-1 in determining clinical outcome. PMID:24220694

Benard, A; van de Velde, C J H; Lessard, L; Putter, H; Takeshima, L; Kuppen, P J K; Hoon, D S B

2013-01-01

405

Radiation therapy for early stage unfavorable Hodgkin lymphoma: is dose reduction feasible?  

PubMed

One hundred and fifty-one patients aged between 3 and 70 years with early stage unfavorable Hodgkin lymphoma were included. Patients received 4-6 cycles of ABVD (doxorubicin, bleomycin, vinblastine and dacarbazine) chemotherapy and involved field radiation therapy (IFRT). The most common histology was mixed cellularity (43%). The majority had stage IIAX disease. IFRT doses were 25.2 Gy/14 fractions and 34.2 Gy/19 fractions for adults with a complete response (CR) and partial response (PR), respectively, while the doses were 19.8 Gy/11 fractions and 30.6 Gy/17 fractions, respectively, for children. After 60 months (median), the 10-year progression-free survival (PFS) and overall survival (OS) were 88.4% and 93.2%, respectively. On univariate analysis, prognostic factors with significant impact on PFS were age ? 18 years, nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) histology, extranodal disease and response to treatment. Extranodal disease had a significant impact on OS. On multivariate analysis, NLPHL histology (p = 0.001) and response at 3 months (p = 0.000) had a significant impact on PFS. There were no in-field relapses in patients with bulky disease receiving RT doses > 25.2 Gy. Chemotherapy related acute pulmonary toxicity was documented in 21.4% and 4.8% of patients after six and four cycles of ABVD chemotherapy (p = 0.041). Four cycles of ABVD and reduced dose IFRT resulted in optimal outcomes. PMID:24354681

Laskar, Siddhartha; Kumar, Deepak P; Khanna, Nehal; Menon, Hari; Sengar, Manju; Arora, Brijesh; Gujral, Sumeet; Shet, Tanuja; Sridhar, Epari; Rangarajan, Venkatesh; Muckaden, Mary Ann; Nair, Reena; Banavali, Shripad

2014-10-01

406

Pair-wise comparison analysis of differential expression of mRNAs in early and advanced stage primary colorectal adenocarcinomas  

PubMed Central

Objectives To characterise the mRNA expression patterns of early and advanced stage colorectal adenocarcinomas of Malaysian patients. Design Comparative expression analysis. Setting and participants We performed a combination of annealing control primer (ACP)-based PCR and reverse transcription-quantitative real-time PCR for the identification of differentially expressed genes (DEGs) associated with early and advanced stage primary colorectal tumours. We recruited four paired samples from patients with colorectal cancer (CRC) of Dukes’ A and B for the preliminary differential expression study, and a total of 27 paired samples, ranging from CRC stages I to IV, for subsequent confirmatory test. The tumouric samples were obtained from the patients with CRC undergoing curative surgical resection without preoperative chemoradiotherapy. The recruited patients with CRC were newly diagnosed with CRC, and were not associated with any hereditary syndromes, previously diagnosed cancer or positive family history of CRC. The paired non-cancerous tissue specimens were excised from macroscopically normal colonic mucosa distally located from the colorectal tumours. Primary and secondary outcome measures The differential mRNA expression patterns of early and advanced stage colorectal adenocarcinomas compared with macroscopically normal colonic mucosa were characterised by ACP-based PCR and reverse transcription-quantitative real-time PCR. Results The RPL35, RPS23 and TIMP1 genes were found to be overexpressed in both early and advanced stage colorectal adenocarcinomas (p<0.05). However, the ARPC2 gene was significantly underexpressed in early colorectal adenocarcinomas, while the advanced stage primary colorectal tumours exhibited an additional overexpression of the C6orf173 gene (p<0.05). Conclusions We characterised two distinctive gene expression patterns to aid in the stratification of primary colorectal neoplasms among Malaysian patients with CRC. Further work can be done to assess and compare the mRNA expression levels of these identified DEGs between each CRC stage group, stages I–IV. PMID:25107436

Lau, Tze Pheng; Roslani, April Camilla; Lian, Lay Hoong; Chai, Hwa Chia; Lee, Ping Chin; Hilmi, Ida; Goh, Khean Lee; Chua, Kek Heng

2014-01-01

407

Early-Stage Primary Bone Lymphoma: A Retrospective, Multicenter Rare Cancer Network (RCN) Study  

SciTech Connect

Purpose: Primary bone lymphoma (PBL) represents less than 1% of all malignant lymphomas. In this study, we assessed the disease profile, outcome, and prognostic factors in patients with Stages I and II PBL. Patients and Methods: Thirteen Rare Cancer Network (RCN) institutions enrolled 116 consecutive patients with PBL treated between 1987 and 2008 in this study. Eighty-seven patients underwent chemoradiotherapy (CXRT) without (78) or with (9) surgery, 15 radiotherapy (RT) without (13) or with (2) surgery, and 14 chemotherapy (CXT) without (9) or with (5) surgery. Median RT dose was 40 Gy (range, 4-60). The median number of CXT cycles was six (range, 2-8). Median follow-up was 41 months (range, 6-242). Results: The overall response rate at the end of treatment was 91% (complete response [CR] 74%, partial response [PR] 17%). Local recurrence or progression was observed in 12 (10%) patients and systemic recurrence in 17 (15%). The 5-year overall survival (OS), lymphoma-specific survival (LSS), and local control (LC) were 76%, 78%, and 92%, respectively. In univariate analyses (log-rank test), favorable prognostic factors for OS and LSS were International Prognostic Index (IPI) score {<=}1 (p = 0.009), high-grade histology (p = 0.04), CXRT (p = 0.05), CXT (p = 0.0004), CR (p < 0.0001), and RT dose >40 Gy (p = 0.005). For LC, only CR and Stage I were favorable factors. In multivariate analysis, IPI score, RT dose, CR, and CXT were independently influencing the outcome (OS and LSS). CR was the only predicting factor for LC. Conclusion: This large multicenter retrospective study confirms the good prognosis of early-stage PBL treated with combined CXRT. An adequate dose of RT and complete CXT regime were associated with better outcome.

Cai Ling [Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, VD (Switzerland); Sun Yat-sen University Cancer Center, Guangzhou, Guangdong (China); Stauder, Michael C. [Mayo Clinic, Rochester, MN (United States); Zhang Yujing [Sun Yat-sen University Cancer Center, Guangzhou, Guangdong (China); Poortmans, Philip [Verbeeten Institute, Tilburg (Netherlands); Li Yexiong [Cancer Hospital, Chinese Academy of Medical Sciences, Beijing (China); Constantinou, Nicolaos [Theagenio Cancer Hospital, Thessaloniki, Macedonia (Greece); Thariat, Juliette [Centre Anti-Cancereux Antoine-Lacassagne, Nice, Cote d'Azur (France); Kadish, Sidney P. [University of Massachusetts Medical School, Worcester, MA (United States); Nguyen, Tan Dat [Institut Jean-Godinot, Reims, Champagne-Ardenne (France); Kirova, Youlia M. [Institut Curie, Paris (France); Ghadjar, Pirus [Inselspital, Bern University Hospital, and University of Bern (Switzerland); Weber, Damien C. [Hopitaux Universitaires de Geneve (Switzerland); Bertran, Victoria Tuset [Hospital Universitari Germans Trias i Pujol, Barcelona (Spain); Ozsahin, Mahmut [Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, VD (Switzerland); Mirimanoff, Rene-Olivier, E-mail: Rene-Olivier.Mirimanoff@chuv.ch [Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, VD (Switzerland)

2012-05-01

408

Sexual Function After Intracavitary Vaginal Brachytherapy for Early-Stage Endometrial Carcinoma  

PubMed Central

Objective To describe the effects of intracavitary brachytherapy (IVB) on sexual function and quality of life of women with early-stage endometrial cancer. Methods Women with International Federation of Gynecology and Obstetrics stage I to stage II endometrial cancer treated surgically with or without IVB were identified and mailed questionnaires. Quality of life and sexual function were measured using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 and the cervical cancer disease-specific module. Pertinent data from prior surgery and radiation treatments were abstracted retrospectively. Linear transformation of the survey subscale scores was conducted per European Organization for Research and Treatment of Cancer guidelines. Results Sixteen women in the IVB arm and 53 in the surgery-alone group completed the survey. Of the sexually active patients, 33% of the IVB patients and 42% of the surgery-alone patients felt their vagina was dry during sexual activity (P = 0.804) and 17% versus 20% felt their vagina was short (P = 0.884). Seventeen percent of patients in the IVB group felt their vagina was tight compared to 29% in the surgery-alone group (P = 0.891) and 0% versus 14% of patients reported pain during intercourse (P = 0.808). There was no statistically significant difference in sexual/vaginal functioning, sexual worry, or sexual enjoyment between the 2 groups. Conclusions Although both groups report vaginal changes that may affect sexual function, the patients treated with IVB reported similar outcomes on a sexual function questionnaire compared to patients treated with surgery alone. PMID:22398710

Quick, Allison M.; Seamon, Leigh G.; Abdel-Rasoul, Mahmoud; Salani, Ritu; Martin, Douglas

2013-01-01

409

Combined chemical and optical methods for monitoring the early decay stages of surrogate human models.  

PubMed

As the body decays shortly after death, a variety of gases and volatile organic compounds (VOCs) constantly emanate. Ethical and practical reasons limit the use of human corpses in controlled, time-dependent, intervening experiments for monitoring the chemistry of body decay. Therefore the utilization of pig carcasses serves as a potential surrogate to human models. The aim of this work was to study buried body decay in conditions of entrapment in collapsed buildings. Six domestic pigs were used to study carcass decay. They were enclosed in plastic body bags after being partially buried with rubbles, resembling entrapment in collapsed buildings. Three experimental cycles were performed, employing two pig carcasses in each cycle; VOCs and inorganic gases were measured daily, along with daily visible and thermal images. VOCs were collected in standard sorbent tubes and subsequently analyzed using a Thermal Desorption/Gas Chromatograph/high sensitivity bench-top Time-of-Flight Mass Spectrometer (TD/GC/TOF-MS). A comprehensive, stage by stage, detailed information on the decay process is being presented based on the experimental macroscopic observations, justifying thus the use of pig carcasses as surrogate material. A variety of VOCs were identified including almost all chemical classes: sulfur, nitrogen, oxygen compounds (aldehydes, alcohols, ketones, acids and esters), hydrocarbons, fluorides and chlorides. Carcasses obtained from a pig farm resulted in more sulfur and nitrogen cadaveric volatiles. Carbon dioxide was by far the most abundant inorganic gas identified along with carbon monoxide, hydrogen sulfide and sulfur dioxide. Visual monitoring was based on video captured images allowing for macroscopic observations, while thermal camera monitoring which is mostly temperature dependent, resulted in highlighting the local micro-changes on the carcasses, as a result of the intense microbial activity. The combination of chemical and optical methods proved very useful and informative, uncovering hidden aspects of the early stages of decay and also guiding in the development of combined chemical and imaging methods for the detection of dead bodies. PMID:21450424

Statheropoulos, M; Agapiou, A; Zorba, E; Mikedi, K; Karma, S; Pallis, G C; Eliopoulos, C; Spiliopoulou, C

2011-07-15

410

[Tactical diagnostic-therapeutic procedures in early stages of vulvar cancer].  

PubMed

The objective of this report is to present the diagnostic and therapeutic tactics in early vulvar carcinoma i.e. carcinoma in situ and carcinoma in I stage (IA and IB) which aim is to limit the radicalisation of the surgery. The clinical material is 57 women aged 27-63 years, colposcopy, cytology and histology diagnosed. The histology examination was made under colposcopic control, and the initial staging was settled i.e. ca in situ in 11 cases, carcinoma IA in 7 cases and carcinoma IB in 39 cases. In qualifying criteria for surgery, unifocal or multifocal location in carcinoma in situ was analysed, and presence of dystrophic lesions in ca in situ and ca IA was taken into consideration. In ca IB the additionally diameter of the lesion (1 cm and 1-2 cm), location (clitoris, perineum, or pudendal lip) and in carcinoma located within the pudendal lip, presence of metastases in lymphatic nodes of inguino-femoral region was taken into consideration. Local excision of lesion was therapeutical procedure in majority of cases in carcinoma in situ and carcinoma IA stage. In multifocal localisation of ca in situ or in coexistence of dystrophic lesions in ca in situ and ca IA vulvectomy was performed. But in carcinoma IB located within the pudendal lips, where lack of metastases to lymphatic nodes in intraoperative histopathology was confirmed, local excision of neoplastic lesion was performed. Presence of lesion within the clitoris, perineum or presence of metastases in lymphatic nodes led to more radical procedure including radical vulvectomy with bilateral lymphadenectomy of inguino-femoral region. PMID:10375936

Basta, A

1999-01-01

411

The ReSTAGE Collaboration: Defining Optimal Bleeding Criteria for Onset of Early Menopausal Transition  

PubMed Central

Study objective Criteria for staging the menopausal transition are not established. This paper evaluates five bleeding criteria for defining early transition and provides empirically-based guidance regarding optimal criteria. Design/Setting Prospective menstrual calendar data from four population-based cohorts: TREMIN, Melbourne Women’s Midlife Health Project(MWMHP), Seattle Midlife Women’s Health Study(SMWHS), and Study of Women’s Health Across the Nation(SWAN) with annual serum follicle stimulating hormone (FSH) from MWMHP and SWAN. Participants 735 TREMIN, 279 SMWHS, 216 MWMHP, and 2270 SWAN women aged 35-57 at baseline who maintained menstrual calendars. Main outcome measure(s) Age at and time to menopause for: standard deviation >6 and >8 days, persistent difference in consecutive segments >6 days, irregularity, and >=45 day segment. Serum follicle stimulating hormone concentration. Results Most women experienced each of the bleeding criteria. Except for persistent >6 day difference which occurs earlier, the criteria occur at a similar age and at approximately the same age as late transition in a large proportion of women. FSH was associated with all proposed markers. Conclusions The early transition may be best described by ovarian activity consistent with the persistent >6 day difference, but further study is needed, as other proposed criterion are consistent with later menstrual changes. PMID:17681300

Harlow, Siobán D.; Mitchell, Ellen S.; Crawford, Sybil; Nan, Bin; Little, Roderick; Taffe, John

2008-01-01

412

Biogeochemical Changes at Early Stage After the Closure of Radioactive Waste Geological Repository in South Korea  

SciTech Connect

Permanent disposal of low- and intermediate-level radioactive wastes in the subterranean environment has been the preferred method of many countries, including Korea. A safety issue after the closure of a geological repository is that biodegradation of organic materials due to microbial activities generates gases that lead to overpressure of the waste containers in the repository and its disintegration with the release of radionuclides. As part of an ongoing large-scale in situ experiment using organic wastes and groundwater to simulate geological radioactive waste repository conditions, we investigated the geochemical alteration and microbial activities at an early stage (~63 days) intended to be representative of the initial period after repository closure. The increased numbers of both aerobes and facultative anaerobes in waste effluents indicate that oxygen content could be the most significant parameter to control biogeochemical conditions at very early periods of reaction (<35 days). Accordingly, the values of dissolved oxygen and redox potential were decreased. The activation of anaerobes after 35 days was supported by the increased concentration to ~50 mg L-1 of ethanol. These results suggest that the biogeochemical conditions were rapidly altered to more reducing and anaerobic conditions within the initial 2 months after repository closure. Although no gases were detected during the study, activated anaerobic microbes will play more important role in gas generation over the long term.

Choung, Sungwook [Pohang Univ. of Science and Technology (Korea, Republic of); Um, Wooyong [Pohang Univ. of Science and Technology (Korea, Republic of); Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Choi, Seho [Pohang Univ. of Science and Technology (Korea, Republic of); Francis, Arokiasamy J. [Pohang Univ. of Science and Technology (Korea, Republic of); Brookhaven National Laboratory (BNL), Upton, NY (United States); Kim, Sungpyo [Korea Univ., Sejong (Korea, Republic of); Park, Jin beak [Korea Radioactive Waste Agency (KORAD), Daejeon (Korea, Republic of); Kim, Suk-Hoon [FNC Technology Co., Seoul National University (Korea, Republic of)

2014-03-18

413

A Report On Eight Early-Stage State And Regional Projects Testing Value-Based Payment  

PubMed Central

To help contain health care spending and improve the quality of care, practitioners and policy makers are trying to move away from fee-for-service toward value-based payment, which links providers’ reimbursement to the value, rather than the volume, of services delivered. With funding from the Robert Wood Johnson Foundation, eight grantees across the country are designing and implementing value-based payment reform projects. For example, in Salem, Oregon, the Physicians Choice Foundation is testing “Program Oriented Payments,” which include incentives for providers who follow a condition-specific program of care designed to meet goals set jointly by patient and provider. In this article we describe the funding rationale and the specific objectives, strategies, progress, and early stages of implementation of the eight projects. We also share some early lessons and identify prerequisites for success, such as ensuring that providers have broad and timely access to data so they can meet patients’ needs in cost-effective ways. PMID:23650332

Conrad, Douglas; Grembowski, David; Gibbons, Claire; Marcus-Smith, Miriam; Hernandez, Susan E.; Chang, Judy; Renz, Anne; Lau, Bernard; Cruz, Erin dela

2014-01-01

414

Effects of Mixture of Pharmaceuticals on Early Life Stages of Tench (Tinca tinca)  

PubMed Central

Ubiquitous occurrence of pharmaceuticals in aquatic environment results in concern about potential adverse the effects on nontarget organisms. In water, drugs are present in complex mixtures, in which complicated interactions affect toxicity of single components. The purpose of this study was to examine effect of 35-day-long exposure to mixture of ibuprofen, diclofenac, and carbamazepine on the mortality, growth, early ontogeny, and histopathological changes in tench (Tinca tinca). Early life stage toxicity test was carried out using a modified protocol according to OECD guideline 210. Exposure to mixture of pharmaceuticals at concentration of 60??g·L?1 for each substance was associated with significant increase in mortality, as well as significant increase in growth and elevated incidence of malformations. Any of the tested concentrations resulted in histopathological changes of liver, kidney, skin, or gill. After fourteen days of exposure there was short-term delay of development related to increased concentrations of pharmaceuticals in the mixture (2, 20, and 60??g·L?1). Environmentally relevant concentrations (0.02; and 0.2??g·L?1) used in this experiment did not result in toxic impairment of tench. PMID:24772417

Stancova, Vlasta; Plhalova, Lucie; Bartoskova, Marta; Zivna, Dana; Prokes, Miroslav; Marsalek, Petr; Blahova, Jana; Skoric, Misa; Svobodova, Zdenka

2014-01-01

415

Relevance of telomere/telomerase system impairment in early stage chronic lymphocytic leukemia.  

PubMed

Several studies have proposed telomere length and telomerase activity as prognostic factors in chronic lymphocytic leukemia (CLL), whereas information addressing the role of telomere-associated genes is limited. We measured relative telomere length (RTL) and TERT expression levels in purified peripheral CD19(+) B-cells from seven healthy donors and 77 untreated CLLs in early stage disease (Binet A). Data were correlated with the major biological and cytogenetic markers, global DNA methylation (Alu and LINE-1), and clinical outcome. The expression profiles of telomere-associated genes were also investigated. RTL was decreased in CLLs as compared with controls (P?early event in CLL pathogenesis. Moreover, the correlation between telomere shortening and global DNA hypomethylation supports the involvement of DNA hypomethylation to increase chromosome instability. © 2014 Wiley Periodicals, Inc. PMID:24706380

Hoxha, Mirjam; Fabris, Sonia; Agnelli, Luca; Bollati, Valentina; Cutrona, Giovanna; Matis, Serena; Recchia, Anna Grazia; Gentile, Massimo; Cortelezzi, Agostino; Morabito, Fortunato; Bertazzi, Pier Alberto; Ferrarini, Manlio; Neri, Antonino

2014-07-01

416

Visualization in an early stage of the problem-solving process in GIS  

NASA Astrophysics Data System (ADS)

Methods of user-computer interaction have remained largely unchanged since the introduction of graphical user interfaces and their popularization by the Apple Macintosh in the early 1980s. Most of today's applications rely on primitive modalities, such as typing and pointing for input generation, which works well for a host of common business applications, but falls short for more complex tasks. To improve the interaction between user and computer we propose a concept that allows people to visualize their ideas, problems, or instructions during the initial phase of an interaction with a computer by augmenting traditional interaction modalities with sketching, gesturing and talking. This approach leads to a more natural user-computer interaction and enhances a user's ability to find solutions to a problem. We suggest that computers become actively involved in the process of problem formulation and that they provide support and give advice where this is adequate. This leads to a process of incremental problem formulation where user and computer are able to better visualize the actual task and fewer misunderstandings occur. Geographic information systems (GIS) would benefit from improved user interaction techniques. GIS are inherently complex and an interaction is often tedious, mostly because such systems are based on sequential and nonspatial input methods that lack the capability of expressing spatial concepts appropriately. We advocate for a visualization in an early stage of the problem solving process in GIS and discuss its advantages and challenges. The paper gives application examples and discusses future research topics.

Blaser, Andreas D.; Sester, Monika; Egenhofer, Max J.

2000-02-01

417

Effects of silver nanocolloids on early life stages of the scleractinian coral Acropora japonica.  

PubMed

In this study, the effects of silver nanocolloids (SNCs) on the early life stages of the reef-building coral Acropora japonica were investigated. The tolerance of this species to SNC contamination was estimated by exposing gametes, larvae, and primary polyps to a range of SNC concentrations (0, 0.5, 5, 50, and 500 ?g l(-1)). Pure SNCs were immediately ionized to Ag(+) in seawater and concentrations of ?50 ?g l(-1) SNC had a significant detrimental effect on fertilization, larval metamorphosis, and primary polyp growth. Exposure to 50 ?g l(-1) SNC did not significantly affect larval survival; however, the larvae were deformed and lost their ability to metamorphose. At the highest concentration (500 ?g l(-1) SNC), all gametes, larvae, and primary polyps died. These experiments provide the first data on the effects of silver-nanomaterial-contaminated seawater on cnidarians, and suggest that silver nanomaterials can influence the early development of corals through anthropogenic wastewater inputs. PMID:25047545

Suwa, Ryota; Kataoka, Chisato; Kashiwada, Shosaku

2014-08-01

418

Early distant relapse in early stage triple-negative breast cancer: usefulness of FDG-PET for diagnosis of distant metastases  

Microsoft Academic Search

Triple-negative breast cancer is extremely aggressive and more likely to metastasize than other subtypes of breast cancer.\\u000a Better understanding of the distinct patterns of relapse and early detection will help identify patients who need aggressive\\u000a treatment. Here we report a case of early stage triple-negative breast cancer with no lymph node metastasis at the time of\\u000a breast-conserving surgery in a

Yukihiro Hama; Keiichi Nakagawa

419

Predictors and Outcomes of Limited Resection for Early-Stage Non–Small Cell Lung Cancer  

PubMed Central

Background Lobectomy is considered the standard treatment for early-stage non–small cell lung cancer (NSCLC); however, more limited resections are commonly performed. We examined patient and surgeon factors associated with limited resection and compared postoperative and long-term outcomes between sublobar and lobar resections. Methods A population- and health system–based sample of patients newly diagnosed with stage I or II NSCLC between 2003 and 2005 in five geographically defined regions, five integrated health-care delivery systems, and 15 Veterans Affairs hospitals was observed for a median of 55 months, through May 31, 2010. Predictors of limited resection and postoperative outcomes were compared using unadjusted and propensity score–weighted analyses. All P values are from two-sided tests. Results One hundred fifty-five (23%) patients underwent limited resection and 524 (77%) underwent lobectomy. In adjusted analyses of patient-specific factors, smaller tumor size (P = .004), coverage by Medicare or Medicaid, no insurance or unknown insurance (P = .02), more severe lung disease (P < .001), and a history of stroke (P = .049) were associated with receipt of limited resection. In adjusted analyses of surgeon characteristics, thoracic surgery specialty (P = .02), non–fee-for-service compensation (P = .008), and National Cancer Institute cancer center designation (P = .006) were associated with higher odds of limited resection. Unadjusted 30-day mortality was higher with limited resection than with lobectomy (7.1% vs 1.9%, difference = 5.2%, 95% confidence interval [CI] = 1.5% to 10.8%, P = .003), and the adjusted difference was not statistically significant (6.5% vs 2.9%, difference = 3.6%, 95% CI = ?.1% to 9.2%, P = .09). Postoperative complications did not differ by type of surgery (all P > .05). Over the course of the study, a non-statistically significant trend toward improved long-term survival was evident for lobectomy, compared with limited resection, in adjusted analyses (hazard ratio of death = 1.35 for limited resection, 95% CI = 0.99 to 1.84, P = .05). Conclusions Evidence is statistically inconclusive but suggestive that lobectomy, compared with limited resection, is associated with increased long-term survival for early-stage lung cancer. Clinical, socioeconomic, and surgeon factors appear to be associated with the choice of surgical resection. PMID:21960708

Ayanian, John Z.; Zaslavsky, Alan M.; Nerenz, David R.; Jaklitsch, Michael T.; Rogers, Selwyn O.

2011-01-01

420

Phytoplankton dynamics in contrasting early stage North Atlantic spring blooms: composition, succession, and potential drivers  

NASA Astrophysics Data System (ADS)

The spring bloom is a key annual event in the phenology of pelagic ecosystems, making a major contribution to the oceanic biological carbon pump through the production and export of organic carbon. However, there is little consensus as to the main drivers of spring bloom formation, exacerbated by a lack of in situ observations of the phytoplankton community composition and its evolution during this critical period. We investigated the dynamics of the phytoplankton community structure at two contrasting sites in the Iceland and Norwegian Basins during the early stage (25 March-25 April) of the 2012 North Atlantic spring bloom. The plankton composition and characteristics of the initial stages of the bloom were markedly different between the two basins. The Iceland Basin (ICB) appeared well mixed to > 400 m, yet surface chlorophyll a (0.27-2.2 mg m-3) and primary production (0.06-0.66 mmol C m-3 d-1) were elevated in the upper 100 m. Although the Norwegian Basin (NWB) had a persistently shallower mixed layer (< 100 m), chlorophyll a (0.58-0.93 mg m-3) and primary production (0.08-0.15 mmol C m-3 d-1) remained lower than in the ICB, with picoplankton (> 2 ?m) dominating chlorophyll a biomass. The ICB phytoplankton composition appeared primarily driven by the physicochemical environment, with periodic events of increased mixing restricting further increases in biomass. In contrast, the NWB phytoplankton community was potentially limited by physicochemical and/or biological factors such as grazing. Diatoms dominated the ICB, with the genus Chaetoceros (1-166 cells mL-1) being succeeded by Pseudo-nitzschia (0.2-210 cells mL-1). However, large diatoms (> 10 ?m) were virtually absent (< 0.5 cells mL-1) from the NWB, with only small nanno-sized (< 5 ?m) diatoms present (101-600 cells mL-1). We suggest micro-zooplankton grazing, potentially coupled with the lack of a seed population of bloom forming diatoms, was restricting diatom growth in the NWB, and that large diatoms may be absent in NWB spring blooms. Despite both phytoplankton communities being in the early stages of bloom formation, different physicochemical and biological factors controlled bloom formation at the two sites. If these differences in phytoplankton composition persist, the subsequent spring blooms are likely to be significantly different in terms of biogeochemistry and trophic interactions throughout the growth season, with important implications for carbon cycling and organic matter export.

Daniels, C. J.; Poulton, A. J.; Esposito, M.; Paulsen, M. L.; Bellerby, R.; St. John, M.; Martin, A. P.

2015-01-01

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