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Sample records for hypertrophic stratified lake

  1. A chemically stratified lake in alaska.

    PubMed

    Likens, G E; Johnson, P L

    1966-08-19

    A meromictic (chemically stratified) lake occupies a thawed depression in a pingo in interior Alaska, near Circle City. Increased salt concentration and anaerobic conditions characterize the zone extending from a maximum depth of 3 to 8.8 meters. The concentration of strontium and lithium is unusually high for lake water. PMID:17780648

  2. Methane metabolism in a stratified boreal lake

    NASA Astrophysics Data System (ADS)

    Nykänen, Hannu; Peura, Sari; Kankaala, Paula; Jones, Roger

    2013-04-01

    Stratified lakes, typical of the boreal zone, are naturally anoxic from their bottoms. In these lakes methanogenesis can account for up to half of organic matter degradation. However, a major part of the methane (CH4) is oxidized in the water column before reaching the atmosphere. Since methanotrophs use CH4 as their sole carbon and energy source, much CH4-derived carbon is incorporated into their biomass. Microbially produced CH4 has strongly negative δ13C compared to other carbon forms in ecosystems, making it possible to follow its route in food webs. However, only a few studies have estimated the amount of this microbial biomass or its carbon stable isotopic composition due to difficulties in separating it from other biomass or from other carbon forms in the water column. We estimated methanotrophic biomass from measured CH4 oxidation, and δ13C of the biomass from measured δ13C values of CH4, DIC, POM and DOC. An estimate of the fraction of methanotrophs in total microbial biomass is derived from bacterial community composition measurements. The study was made in, Alinen Mustajärvi, a small (area 0.75 ha, maximum depth 6.5 m, mean depth 4.2 m,), oligotrophic, mesohumic headwater lake located in boreal coniferous forest in southern Finland. CH4 and DIC concentrations and their δ13C were measured over the deepest point of the lake at 1 m intervals. 13C of DOM and POM were analyzed from composite samples from epi-, meta-, and hypolimnion. Evasion of CH4 and carbon dioxide from the lake surface to the atmosphere was estimated with boundary layer diffusion equations. CH4oxidation was estimated by comparing differences between observed concentrations and CH4potentially transported by turbulent diffusion between different vertical layers in the lake and also by actual methanotrophy measurements and from vertical differences in δ13C-CH4. The estimate of CH4 production was based on the sum of oxidized and released CH4. Molecular microbiology methods were used to

  3. Identification of Major Planktonic Sulfur Oxidizers in Stratified Freshwater Lake

    PubMed Central

    Kojima, Hisaya; Watanabe, Tomohiro; Iwata, Tomoya; Fukui, Manabu

    2014-01-01

    Planktonic sulfur oxidizers are important constituents of ecosystems in stratified water bodies, and contribute to sulfide detoxification. In contrast to marine environments, taxonomic identities of major planktonic sulfur oxidizers in freshwater lakes still remain largely unknown. Bacterioplankton community structure was analyzed in a stratified freshwater lake, Lake Mizugaki in Japan. In the clone libraries of 16S rRNA gene, clones very closely related to a sulfur oxidizer isolated from this lake, Sulfuritalea hydrogenivorans, were detected in deep anoxic water, and occupied up to 12.5% in each library of different water depth. Assemblages of planktonic sulfur oxidizers were specifically analyzed by constructing clone libraries of genes involved in sulfur oxidation, aprA, dsrA, soxB and sqr. In the libraries, clones related to betaproteobacteria were detected with high frequencies, including the close relatives of Sulfuritalea hydrogenivorans. PMID:24695535

  4. VERTICAL DIFFUSION IN SMALL STRATIFIED LAKES: DATA AND ERROR ANALYSIS

    EPA Science Inventory

    Water temperature profiles were measured at 2-min intervals in a stratified temperate lake with a surface area of 0.06 km2 and a aximum depth of 10 m from May 7 to August 9, 1989. he data were used to calculate the vertical eddy diffusion coefficient K2 in the hypolimnion. he dep...

  5. TEMPERATURES AND CURRENTS IN A STRATIFIED LAKE: A TWO-DIMENSIONAL ANALYSIS

    EPA Science Inventory

    Two-dimensional, time-dependent numerical models are used to predict the temperatures and currents in a stratified lake. In this study, (1) essential features of the observed distributions of temperatures and currents in large, stratified lakes, especially Lake Erie, are reproduc...

  6. Heterotrophic bacterioplankton control on organic and inorganic carbon cycle in stratified and non-stratified lakes of NW Russia

    NASA Astrophysics Data System (ADS)

    Shirokova, Liudmila; Vorobjeva, Taissia; Zabelina, Svetlana; Moreva, Olga; Klimov, Sergey; Shorina, Natalja; Chupakov, Artem; Pokrovsky, Oleg; Audry, Stephan; Viers, Jerome

    2010-05-01

    Lakes of boreal zone regulate the fate of dissolved carbon, nutrients and trace metals during their transport from the watershed to the ocean. Study of primary production - mineralization processes in the context of carbon biogeochemical cycle allows determination of the rate and mechanisms of phytoplankton biomass production and its degradation via aquatic heterotrophic bacteria. In particular, comparative study of vertical distribution of Dissolved Organic Carbon (DOC) in stratified and non-stratified lakes allows establishing the link between biological and chemical aspects of the carbon cycle which, in turns, determines an environmental stability and recovering potential of the entire ecosystem. In order to better understand the biogeochemical mechanisms that control dissolved organic and inorganic carbon migration in surface boreal waters, we studied in 2007-2009 two strongly stratified lakes (15-20 m deep) and two shallow lakes (2-4 m deep) in the Arkhangelsk region (NW Russia, White Sea basin). We conducted natural experiments of the lake water incubation for measurements of the intensity of production/mineralization processes and we determined vertical concentration of DOC during four basic hydrological seasons (winter and summer stratification, and spring and autumn lake overturn). Our seasonal studies of production/mineralization processes demonstrated high intensity of organic matter formation during summer period and significant retard of these processes during winter stagnation. During spring period, there is a strong increase of bacterial destruction of the allochtonous organic matter that is being delivered to the lake via terrigenous input. During autumn overturn, there is a decrease of the activity of phytoplankton, and the degradation of dead biomass by active bacterial community. Organic matter destruction processes are the most active in Svyatoe lake, whereas in the Beloe lake, the rate of organic matter production is significantly higher than

  7. Statistics of microstructure patchiness in a stratified lake

    NASA Astrophysics Data System (ADS)

    Planella Morato, J.; Roget, E.; Lozovatsky, I.

    2011-10-01

    Statistics of microstructure patches in a sheared, strongly stratified metalimnion of Lake Banyoles (Catalonia, Spain), which occupied ˜40% of the total lake depth of 12 m, are analyzed. Light winds (<3 m s-1) dominated the periods of observation in late June and early July of 2009. The patch sizes hp and the corresponding patch Thorpe scales LTp were identified using profiling measurements of temperature microstructure and small-scale shear. The distribution of hp was found to be lognormal with mean and median values of 0.69 m and 0.50 m respectively. The distribution of LTp within the patches was also fitted to a lognormal model and the mean and median values found to be close to 0.1 m. The probability distribution of the ratio LTp/hp was approximated by the Weibull probability model with a shape parameter cw ≈ 2, and also by beta probability distribution. For hp > 0.25 m, the ratio LTp/hp depends on the patch Richardson and mixing Reynolds numbers following the parameterization of Lozovatsky and Fernando (2002). Analysis of the dynamics of mixing reveals that averaged vertical diffusivities ranged between ˜1 × 10-4 m2 s-1 and ˜5 × 10-5 m2 s-1, depending on the phase of the internal waves. Episodic wind gusts (wind speed above 6 m s-1) transfer ˜1.6% of the wind energy to the metalimnion and ˜0.7% to the hypolimnion, generating large microstructure patches with hp of several meters.

  8. Rising CO2 Levels Will Intensify Phytoplankton Blooms in Eutrophic and Hypertrophic Lakes

    PubMed Central

    Verspagen, Jolanda M. H.; Van de Waal, Dedmer B.; Finke, Jan F.; Visser, Petra M.; Van Donk, Ellen; Huisman, Jef

    2014-01-01

    Harmful algal blooms threaten the water quality of many eutrophic and hypertrophic lakes and cause severe ecological and economic damage worldwide. Dense blooms often deplete the dissolved CO2 concentration and raise pH. Yet, quantitative prediction of the feedbacks between phytoplankton growth, CO2 drawdown and the inorganic carbon chemistry of aquatic ecosystems has received surprisingly little attention. Here, we develop a mathematical model to predict dynamic changes in dissolved inorganic carbon (DIC), pH and alkalinity during phytoplankton bloom development. We tested the model in chemostat experiments with the freshwater cyanobacterium Microcystis aeruginosa at different CO2 levels. The experiments showed that dense blooms sequestered large amounts of atmospheric CO2, not only by their own biomass production but also by inducing a high pH and alkalinity that enhanced the capacity for DIC storage in the system. We used the model to explore how phytoplankton blooms of eutrophic waters will respond to rising CO2 levels. The model predicts that (1) dense phytoplankton blooms in low- and moderately alkaline waters can deplete the dissolved CO2 concentration to limiting levels and raise the pH over a relatively wide range of atmospheric CO2 conditions, (2) rising atmospheric CO2 levels will enhance phytoplankton blooms in low- and moderately alkaline waters with high nutrient loads, and (3) above some threshold, rising atmospheric CO2 will alleviate phytoplankton blooms from carbon limitation, resulting in less intense CO2 depletion and a lesser increase in pH. Sensitivity analysis indicated that the model predictions were qualitatively robust. Quantitatively, the predictions were sensitive to variation in lake depth, DIC input and CO2 gas transfer across the air-water interface, but relatively robust to variation in the carbon uptake mechanisms of phytoplankton. In total, these findings warn that rising CO2 levels may result in a marked intensification of

  9. Effect of eddy diffusivity on wind-driven currents in a two-layer stratified lake

    NASA Technical Reports Server (NTRS)

    Gedney, R. T.; Lick, W.; Molls, F. B.

    1972-01-01

    The steady state wind-driven circulation was numerically calculated in a rectangular stratified lake. The lake is composed of two layers having uniform but unequal densities and eddy diffusivities. The position in thermocline and the three-dimensional velocities in both layers calculated using shallow lake equations. The results show that, as the eddy diffusivity in the hypolimnion is increased, the thermocline tilt and hypolimnetic velocities increase. The effect of the other variables such as wind stress, density, basin length, and mean thermocline depth are also shown.

  10. Buoyancy flux, turbulence, and the gas transfer coefficient in a stratified lake

    NASA Astrophysics Data System (ADS)

    MacIntyre, Sally; Jonsson, Anders; Jansson, Mats; Aberg, Jan; Turney, Damon E.; Miller, Scott D.

    2010-12-01

    Gas fluxes from lakes and other stratified water bodies, computed using conservative values of the gas transfer coefficient k600, have been shown to be a significant component of the carbon cycle. We present a mechanistic analysis of the dominant physical processes modifying k600 in a stratified lake and resulting new models of k600 whose use will enable improved computation of carbon fluxes. Using eddy covariance results, we demonstrate that i) higher values of k600 occur during low to moderate winds with surface cooling than with surface heating; ii) under overnight low wind conditions k600 depends on buoyancy flux β rather than wind speed; iii) the meteorological conditions at the time of measurement and the inertia within the lake determine k600; and iv) eddy covariance estimates of k600 compare well with predictions of k600 using a surface renewal model based on wind speed and β.

  11. Community shift from phototrophic to chemotrophic sulfide oxidation following anoxic holomixis in a stratified seawater lake.

    PubMed

    Pjevac, Petra; Korlević, Marino; Berg, Jasmine S; Bura-Nakić, Elvira; Ciglenečki, Irena; Amann, Rudolf; Orlić, Sandi

    2015-01-01

    Most stratified sulfidic holomictic lakes become oxygenated after annual turnover. In contrast, Lake Rogoznica, on the eastern Adriatic coast, has been observed to undergo a period of water column anoxia after water layer mixing and establishment of holomictic conditions. Although Lake Rogoznica's chemistry and hydrography have been studied extensively, it is unclear how the microbial communities typically inhabiting the oxic epilimnion and a sulfidic hypolimnion respond to such a drastic shift in redox conditions. We investigated the impact of anoxic holomixis on microbial diversity and microbially mediated sulfur cycling in Lake Rogoznica with an array of culture-independent microbiological methods. Our data suggest a tight coupling between the lake's chemistry and occurring microorganisms. During stratification, anoxygenic phototrophic sulfur bacteria were dominant at the chemocline and in the hypolimnion. After an anoxic mixing event, the anoxygenic phototrophic sulfur bacteria entirely disappeared, and the homogeneous, anoxic water column was dominated by a bloom of gammaproteobacterial sulfur oxidizers related to the GSO/SUP05 clade. This study is the first report of a community shift from phototrophic to chemotrophic sulfide oxidizers as a response to anoxic holomictic conditions in a seasonally stratified seawater lake. PMID:25344237

  12. Community Shift from Phototrophic to Chemotrophic Sulfide Oxidation following Anoxic Holomixis in a Stratified Seawater Lake

    PubMed Central

    Korlević, Marino; Berg, Jasmine S.; Bura-Nakić, Elvira; Ciglenečki, Irena; Amann, Rudolf; Orlić, Sandi

    2014-01-01

    Most stratified sulfidic holomictic lakes become oxygenated after annual turnover. In contrast, Lake Rogoznica, on the eastern Adriatic coast, has been observed to undergo a period of water column anoxia after water layer mixing and establishment of holomictic conditions. Although Lake Rogoznica's chemistry and hydrography have been studied extensively, it is unclear how the microbial communities typically inhabiting the oxic epilimnion and a sulfidic hypolimnion respond to such a drastic shift in redox conditions. We investigated the impact of anoxic holomixis on microbial diversity and microbially mediated sulfur cycling in Lake Rogoznica with an array of culture-independent microbiological methods. Our data suggest a tight coupling between the lake's chemistry and occurring microorganisms. During stratification, anoxygenic phototrophic sulfur bacteria were dominant at the chemocline and in the hypolimnion. After an anoxic mixing event, the anoxygenic phototrophic sulfur bacteria entirely disappeared, and the homogeneous, anoxic water column was dominated by a bloom of gammaproteobacterial sulfur oxidizers related to the GSO/SUP05 clade. This study is the first report of a community shift from phototrophic to chemotrophic sulfide oxidizers as a response to anoxic holomictic conditions in a seasonally stratified seawater lake. PMID:25344237

  13. Biogeochemistry of natural gases in three alkaline, permanently stratified (meromictic) lakes

    SciTech Connect

    Oremland, R.S.; Miller, L.G. )

    1993-01-01

    Methane and associated light hydrocarbons are present as dissolved gases in the water columns of three alkaline, permanently stratified (meromictic) lakes: Big Soda Lake (Nevada), Mono Lake (California), and Soap Lake (Washington). Methane originates in the bottom sediments, but higher gaseous hydrocarbons (that is, gaseous hydrocarbons of higher molecular weight) have either microbial or thermal sources in the different lakes. Stable isotopic composition, hydrocarbon indices, radiocarbon dating, abundance-versus-depth profiles, and biological experiments indicate that methane is formed in the sediments by microbial processes. Methanogenesis and sulfate-reduction have much higher activity in the shallow littoral sediments than in the colder, more saline pelagic sediments of all three lakes. Methane-rich gas seeps are common in Mono Lake and emanate from a natural-gas deposit underlying the current lakebed. Seeps do not occur in either Big Soda Lake or Soap Lake. Ethane and higher alkanes are present in Big Soda Lake and Mono Lake, but are not present in significant quantities in Soap Lake. It is not clear if the presence of these higher alkanes is a consequence of biological activity, a result of mixing with thermogenic gases, or a combination of both factors. These results indicate the potential complexity and diversity encountered in studying light-hydrocarbon biogeochemistry in thermally and microbially active systems. Hence, in the case of methane, detailed multidisciplinary studies are often needed to determine its origin. For ethane and higher alkanes, there is currently a paucity of basic scientific information to allow for unequivocal identification of microbial and thermogenetic sources. 61 refs., 12 figs., 6 tabs.

  14. Vertical distribution of microbial communities in a perennially stratified Arctic lake with saline, anoxic bottom waters

    PubMed Central

    Comeau, André M.; Harding, Tommy; Galand, Pierre E.; Vincent, Warwick F.; Lovejoy, Connie

    2012-01-01

    Meromictic lakes are useful biogeochemical models because of their stratified chemical gradients and separation of redox reactions down the water column. Perennially ice-covered meromictic lakes are particularly stable, with long term constancy in their density profiles. Here we sampled Lake A, a deep meromictic lake at latitude 83°N in High Arctic Canada. Sampling was before (May) and after (August) an unusual ice-out event during the warm 2008 summer. We determined the bacterial and archaeal community composition by high-throughput 16S rRNA gene tag-pyrosequencing. Both prokaryote communities were stratified by depth and the Bacteria differed between dates, indicating locally driven selection processes. We matched taxa to known taxon-specific biogeochemical functions and found a close correspondence between the depth of functional specialists and chemical gradients. These results indicate a rich microbial diversity despite the extreme location, with pronounced vertical structure in taxonomic and potential functional composition, and with community shifts during ice-out. PMID:22930670

  15. Light-Dependent Aerobic Methane Oxidation Reduces Methane Emissions from Seasonally Stratified Lakes

    PubMed Central

    Oswald, Kirsten; Milucka, Jana; Brand, Andreas; Littmann, Sten; Wehrli, Bernhard; Kuypers, Marcel M. M.; Schubert, Carsten J.

    2015-01-01

    Lakes are a natural source of methane to the atmosphere and contribute significantly to total emissions compared to the oceans. Controls on methane emissions from lake surfaces, particularly biotic processes within anoxic hypolimnia, are only partially understood. Here we investigated biological methane oxidation in the water column of the seasonally stratified Lake Rotsee. A zone of methane oxidation extending from the oxic/anoxic interface into anoxic waters was identified by chemical profiling of oxygen, methane and δ13C of methane. Incubation experiments with 13C-methane yielded highest oxidation rates within the oxycline, and comparable rates were measured in anoxic waters. Despite predominantly anoxic conditions within the zone of methane oxidation, known groups of anaerobic methanotrophic archaea were conspicuously absent. Instead, aerobic gammaproteobacterial methanotrophs were identified as the active methane oxidizers. In addition, continuous oxidation and maximum rates always occurred under light conditions. These findings, along with the detection of chlorophyll a, suggest that aerobic methane oxidation is tightly coupled to light-dependent photosynthetic oxygen production both at the oxycline and in the anoxic bottom layer. It is likely that this interaction between oxygenic phototrophs and aerobic methanotrophs represents a widespread mechanism by which methane is oxidized in lake water, thus diminishing its release into the atmosphere. PMID:26193458

  16. Protistan diversity in a permanently stratified meromictic lake (Lake Alatsee, SW Germany).

    PubMed

    Oikonomou, Andreas; Filker, Sabine; Breiner, Hans-Werner; Stoeck, Thorsten

    2015-06-01

    Protists play a crucial role for ecosystem function(ing) and oxygen is one of the strongest barriers against their local dispersal. However, protistan diversity in freshwater habitats with oxygen gradients received very little attention. We applied high-throughput sequencing of the V9 region (18S rRNA gene) to provide a hitherto unique spatiotemporal analysis of protistan diversity along the oxygen gradient of a freshwater meromictic lake (Lake Alatsee, SW Germany). In the mixolimnion, the communities experienced most seasonal structural changes, with Stramenopiles dominating in autumn and Dinoflagellata in summer. The suboxic interface supported the highest diversity, but only 23 OTUs95% (mainly Euglenozoa, after quality check and removal of operational taxonomic units (OTUs) with less than three sequences) were exclusively associated with this habitat. Eukaryotic communities in the anoxic monimolimnion showed the most stable seasonal pattern, with Chrysophyta and Bicosoecida being the dominant taxa. Our data pinpoint to the ecological role of the interface as a short-term 'meeting point' for protists, contributing to the coupling of the mixolimnion and the monimolimnion. Our analyses of divergent genetic diversity suggest a high degree of previously undescribed OTUs. Future research will have to reveal if this result actually points to a high number of undescribed species in such freshwater habitats. PMID:25330396

  17. Vertical stratification of bacteria and archaea in sediments of a boreal stratified humic lake

    NASA Astrophysics Data System (ADS)

    Rissanen, Antti J.; Mpamah, Promise; Peura, Sari; Taipale, Sami; Biasi, Christina; Nykänen, Hannu

    2015-04-01

    Boreal stratified humic lakes, with steep redox gradients in the water column and in the sediment, are important sources of methane (CH4) to the atmosphere. CH4 flux from these lakes is largely controlled by the balance between CH4-production (methanogenesis), which takes place in the organic rich sediment and in the deepest water layers, and CH4-consumption (methanotrophy), which takes place mainly in the water column. While there is already some published information on the activity, diversity and community structure of bacteria in the water columns of these lakes, such information on sediment microbial communities is very scarce. This study aims to characterize the vertical variation patterns in the diversity and the structure of microbial communities in sediment of a boreal stratified lake. Particular focus is on microbes with the potential to contribute to methanogenesis (fermentative bacteria and methanogenic archaea) and to methanotrophy (methanotrophic bacteria and archaea). Two sediment cores (26 cm deep), collected from the deepest point (~6 m) of a small boreal stratified lake during winter-stratification, were divided into depth sections of 1 to 2 cm for analyses. Communities were studied from DNA extracted from sediment samples by next-generation sequencing (Ion Torrent) of polymerase chain reaction (PCR) - amplified bacterial and archaeal 16S rRNA gene amplicons. The abundance of methanogenic archaea was also specifically studied by quantitative-PCR of methyl coenzyme-M reductase gene (mcrA) amplicons. Furthermore, the community structure and the abundance of bacteria were studied by phospholipid fatty acid (PLFA) analysis. Dominant potential fermentative bacteria belonged to families Syntrophaceae, Clostridiaceae and Peptostreptococcaceae. There were considerable differences in the vertical distribution among these groups. The relative abundance of Syntrophaceae started to increase from the sediment surface, peaked at depth layer from 5 to 10 cm (up

  18. Response in the trophic state of stratified lakes to changes in hydrology and water level: potential effects of climate change

    USGS Publications Warehouse

    Robertson, Dale M.; Rose, William J.

    2011-01-01

    To determine how climate-induced changes in hydrology and water level may affect the trophic state (productivity) of stratified lakes, two relatively pristine dimictic temperate lakes in Wisconsin, USA, were examined. Both are closed-basin lakes that experience changes in water level and degradation in water quality during periods of high water. One, a seepage lake with no inlets or outlets, has a small drainage basin and hydrology dominated by precipitation and groundwater exchange causing small changes in water and phosphorus (P) loading, which resulted in small changes in water level, P concentrations, and productivity. The other, a terminal lake with inlets but no outlets, has a large drainage basin and hydrology dominated by runoff causing large changes in water and P loading, which resulted in large changes in water level, P concentrations, and productivity. Eutrophication models accurately predicted the effects of changes in hydrology, P loading, and water level on their trophic state. If climate changes, larger changes in hydrology and water levels than previously observed could occur. If this causes increased water and P loading, stratified (dimictic and monomictic) lakes are expected to experience higher water levels and become more eutrophic, especially those with large developed drainage basins.

  19. Depth distribution of bacterial production in a stratified lake with an anoxic hypolimnion

    SciTech Connect

    McDonough, R.J.; Sanders, R.W.; Porter, K.G.; Kirchman, D.L.

    1986-11-01

    The purpose of this study was to determine the depth distribution of bacterial biomass and production in a stratified lake and to test techniques to measure bacterial production in anaerobic waters. Bacterial abundance and incorporation of both (/sup 3/H)thymidine and (/sup 3/H)leucine into protein were highest in the metalimnion, at the depth at which oxygen first became unmeasurable. In contrast, (/sup 3/H)thymidine incorporation into DNA was highest in the epilimnion. Recovery of added (/sup 3/H)DNA was about 90% in waters in which the portion of (/sup 3/H)thymidine incorporation into DNA was about 40%. At least some obligate anaerobic bacteria were capable of assimilating thymidine since aeration of anaerobic hypolimnion waters substantially inhibited thymidine incorporation. The depth profile of bacterial production estimated from total thymidine and leucine incorporation and the frequency of dividing cells were all similar, with maximal rates in the metalimnion. However, estimates of bacterial production based on frequency of dividing cells and leucine incorporation were usually significantly higher than estimates based on thymidine incorporation (using conversion factors from the literature), especially in anaerobic hypolimnion waters. These data indicate that the thymidine approach must be examined carefully if it is to be applied to aquatic systems with low oxygen concentrations. The results also indicate that the interface between the aerobic epilimnion and anaerobic hypolimnion is the site of intense bacterial mineralization and biomass production which deserves further study.

  20. Interference pattern of the sound field in the presence of an internal Kelvin wave in a stratified lake.

    PubMed

    Katsnelson, Boris; Lunkov, Andrey; Ostrovsky, Ilia

    2016-02-01

    Internal Kelvin waves (IKWs) initiated by rotation of the Earth are one of the main hydrodynamic phenomena in large stratified lakes where baroclinic Rossby radius of deformation is smaller than the horizontal scale of the lake. IKWs can be identified using the spectra of internal waves, where in the presence of IKWs, the inertial frequency is at maximum. IKWs play a rather important role in the lake's dynamics for different processes, both in the water layer and sediment, especially at the periphery of lake. Due to influence of internal waves on the sound propagation, acoustical methods can be used for estimation of behaviour of IKWs. In this paper, the spatiotemporal variability of the mid-frequency (∼1 kHz) sound field in the presence of IKWs in a deep stratified Lake Kinneret is studied using numerical simulations based on normal-mode theory. Due to the specific character of perturbation of the water layer, IKWs can cause specific variations of interference pattern, in particular, a significant shift of the sound interference pattern both in spatial and frequency domain. These shifts can be easily measured and used for reconstruction of IKW parameters. PMID:26936569

  1. Controlling Cyanobacterial Blooms in Hypertrophic Lake Taihu, China: Will Nitrogen Reductions Cause Replacement of Non-N2 Fixing by N2 Fixing Taxa?

    PubMed Central

    Paerl, Hans W.; Xu, Hai; Hall, Nathan S.; Zhu, Guangwei; Qin, Boqiang; Wu, Yali; Rossignol, Karen L.; Dong, Linghan; McCarthy, Mark J.; Joyner, Alan R.

    2014-01-01

    Excessive anthropogenic nitrogen (N) and phosphorus (P) inputs have caused an alarming increase in harmful cyanobacterial blooms, threatening sustainability of lakes and reservoirs worldwide. Hypertrophic Lake Taihu, China’s third largest freshwater lake, typifies this predicament, with toxic blooms of the non-N2 fixing cyanobacteria Microcystis spp. dominating from spring through fall. Previous studies indicate N and P reductions are needed to reduce bloom magnitude and duration. However, N reductions may encourage replacement of non-N2 fixing with N2 fixing cyanobacteria. This potentially counterproductive scenario was evaluated using replicate, large (1000 L), in-lake mesocosms during summer bloom periods. N+P additions led to maximum phytoplankton production. Phosphorus enrichment, which promoted N limitation, resulted in increases in N2 fixing taxa (Anabaena spp.), but it did not lead to significant replacement of non-N2 fixing with N2 fixing cyanobacteria, and N2 fixation rates remained ecologically insignificant. Furthermore, P enrichment failed to increase phytoplankton production relative to controls, indicating that N was the most limiting nutrient throughout this period. We propose that Microcystis spp. and other non-N2 fixing genera can maintain dominance in this shallow, highly turbid, nutrient-enriched lake by outcompeting N2 fixing taxa for existing sources of N and P stored and cycled in the lake. To bring Taihu and other hypertrophic systems below the bloom threshold, both N and P reductions will be needed until the legacy of high N and P loading and sediment nutrient storage in these systems is depleted. At that point, a more exclusive focus on P reductions may be feasible. PMID:25405474

  2. Effect of bottom topography, eddy diffusivity, and wind variation on circulation in a two-layer stratified lake

    NASA Technical Reports Server (NTRS)

    Gedney, R. T.; Lick, W.; Molls, F. B.

    1973-01-01

    The steady-state, wind-driven circulation is calculated in a stratified lake composed of two layers having uniform but unequal densities and eddy diffusivities. The position of the thermocline and the velocities in both layers are calculated from an asymptotic solution of the shallow lake equations when the Ekman number in the epilimnion (upper layer) is of order one but the ratio of hypolimnion (lower layer) to epilimnion eddy diffusivities is much less than one. Large differences in the thermocline shape and the velocities occur between the solution for uniform wind stress and the one for unit order wind stress gradients. For the latter solution the hypolimnion eddy diffusivity magnitude and the bottom topography have a large and important effect.

  3. Spatial and Temporal Variation in Methane Bubbling From a Stratified, Eutrophic Lake

    NASA Astrophysics Data System (ADS)

    Varadharajan, C.; Borja, E.; Tcaciuc, A. P.; Hemond, H. F.

    2008-12-01

    Recent studies have suggested that significant amounts of methane can be released to the atmosphere from freshwater lakes, particularly through bubbling. However, spatial and temporal heterogeneity in ebullition has complicated efforts to accurately measure methane emissions from aquatic ecosystems. We have hypothesized that bubbling is triggered by variations in absolute water pressure at the lake bottom, and hence should be more or less synchronous from site to site within a small lake. In 2007, most of the bubbling in the eutrophic Upper Mystic Lake in Massachusetts occurred episodically, with peak fluxes approaching 200 ml/m2/d in late summer and early fall (comparable to wetland emissions), while average bubble fluxes were approximately 30-45 ml/m2/d. However the temporal resolution of these measurements was only of the order of a week. In 2008, under-water bubble traps were equipped with pressure sensors that measured the gas collected every 5 minutes, to determine the exact temporal pattern of ebullition. Early results suggest that synchronous lake-wide bubbling occurs during episodes lasting 2 to 4 days, and is in fact strongly linked with changes in the lake's water level, and to a lesser extent with variations in atmospheric pressure. Spatial variability in bubble fluxes was observed during both years, with shallower locations emitting 2 to 20 times less flux than deeper stations. The mixing ratio of methane present in the collected gas varied across stations and ranged from 30% to 90%.

  4. Quadruple sulfur isotope constraints on the origin and cycling of volatile organic sulfur compounds in a stratified sulfidic lake

    NASA Astrophysics Data System (ADS)

    Oduro, Harry; Kamyshny, Alexey; Zerkle, Aubrey L.; Li, Yue; Farquhar, James

    2013-11-01

    We have quantified the major forms of volatile organic sulfur compounds (VOSCs) distributed in the water column of stratified freshwater Fayetteville Green Lake (FGL), to evaluate the biogeochemical pathways involved in their production. The lake's anoxic deep waters contain high concentrations of sulfate (12-16 mmol L-1) and sulfide (0.12 μmol L-1 to 1.5 mmol L-1) with relatively low VOSC concentrations, ranging from 0.1 nmol L-1 to 2.8 μmol L-1. Sulfur isotope measurements of combined volatile organic sulfur compounds demonstrate that VOSC species are formed primarily from reduced sulfur (H2S/HS-) and zero-valent sulfur (ZVS), with little input from sulfate. Thedata support a role of a combination of biological and abiotic processes in formation of carbon-sulfur bonds between reactive sulfur species and methyl groups of lignin components. These processes are responsible for very fast turnover of VOSC species, maintaining their low levels in FGL. No dimethylsulfoniopropionate (DMSP) was detected by Electrospray Ionization Mass Spectrometry (ESI-MS) in the lake water column or in planktonic extracts. These observations indicate a pathway distinct from oceanic and coastal marine environments, where dimethylsulfide (DMS) and other VOSC species are principally produced via the breakdown of DMSP by plankton species.

  5. Time-series analysis of high-resolution ebullition fluxes from a stratified, freshwater lake

    NASA Astrophysics Data System (ADS)

    Varadharajan, Charuleka; Hemond, Harold F.

    2012-06-01

    Freshwater lakes can emit significant quantities of methane to the atmosphere by bubbling. The high spatial and temporal heterogeneity of ebullition, combined with a lack of high-resolution field measurements, has made it difficult to accurately estimate methane fluxes or determine the underlying mechanisms for bubble release. We use a high-temporal resolution data set of ebullitive fluxes from the eutrophic Upper Mystic Lake, Massachusetts to understand the triggers that lead to bubbling from submerged sediments. A wavelet approach is introduced to detect ebullition events for multiple time-scales, and is complemented with traditional statistical methods for data analyses. We show that bubble release from lake sediments occurred synchronously at several sites, and was closely associated with small, aperiodic drops in total hydrostatic pressure. Such results are essential to constrain mechanistic models and to design future measurement schemes, particularly with respect to the temporal scales that are needed to accurately observe and quantify ebullition in aquatic ecosystems.

  6. High-Temporal-Resolution Measurement of Methane Ebullition From a Stratified, Eutrophic Lake

    NASA Astrophysics Data System (ADS)

    Varadharajan, C.; Borja, E.; Tcaciuc, A. P.; Hemond, H. F.

    2009-04-01

    Significant amounts of methane can be released to the atmosphere from freshwater lakes, particularly through bubbling. However, spatial and temporal heterogeneity in ebullition has complicated efforts to accurately measure such methane emissions. In 2007, bubbling from the Upper Mystic Lake in Massachusetts, US was strongly episodic, with peak fluxes at the water surface approaching 200 ml/m2/d in late summer and fall, while average bubble fluxes were approximately 30-45 ml/m2/d. However the temporal resolution of these measurements was only of the order of a week. In 2008, under-water bubble traps were equipped with pressure sensors that measured the gas collected every 5 minutes. Episodes of bubbling were almost synchronous throughout the lake and tended to last for several days, though the amount and composition of gas released from the sediment varied considerably between sites. The onset of bubbling episodes is correlated with drops in hydrostatic pressure that occurred during periods of low lake water levels. Ebullition fluxes in 2008 were a factor of 2 less than 2007 fluxes, although the spatial pattern of bubbling was similar in both years, with deeper locations generally bubbling more than shallow sites. However, in some cases fluxes varied by as much as a factor of 20 between stations that were only 15-30 m apart, which indicates that sediment methane sources could be highly localized. The mixing ratio of methane present in the collected gas ranged from 30% to 90%, and was generally higher at locations that bubbled more. The partial pressure of total methane present in the lake sediments was found to be 2

  7. Stratified tephra records from lake sediment archives: Holocene eruptions of the Virunga Volcanic Province, East African Rift

    NASA Astrophysics Data System (ADS)

    Lane, Christine; Scholz, Christopher; Poppe, Sam; Schmid, Martin; Ross, Kelly Ann

    2016-04-01

    Lake sediments preserve rare stratified records of explosive volcanism, often with accompanying chronological controls or climatostratigraphic detail. In proximal areas where outcrop stratigraphies are complex, exposures isolated and sediments frequently eroded, the lacustrine archive provides a means to check the order of events and identify additional eruptions not preserved on land. The visible volcanic ash (tephra) record within lake sediments may be limited by eruption volume, distance from source and high sedimentation rates. A more complete eruption history can be detected through the study of non-visible tephra layers. Such "cryptotephra" records may be revealed through non-destructive core-scanning methods, such as XRF-scanning or magnetic susceptibility measurements, or by more thorough laboratory processes and microscopic analysis. Compositional analysis of tephra glass shards using WDS-EPMA and LA-ICP-MS provide a means to provenance eruptions, to cross-correlate between multiple sediment cores, and to establish connections between the lacustrine record and proximal outcrops. Here we present the results of such a "tephrostratigraphic" approach applied to the Holocene volcanic record of the Virunga Volcanic Province (VVP). More than 10 explosive volcanic eruptions, attributed to multiple volcanic centres, are evidenced over the last 12,000 years. This unique insight into the frequency of explosive eruptions from the VVP, demonstrates the potential of visible and cryptotephra investigations in lacustrine sediment archives as a means of studying past, present and future volcanic hazards.

  8. Stratified distribution of nutrients and extremophile biota within freshwater ice covering the surface of Lake Baikal.

    PubMed

    Bondarenko, Nina A; Belykh, Olga I; Golobokova, Ludmila P; Artemyeva, Olga V; Logacheva, Natalia F; Tikhonova, Irina V; Lipko, Irina A; Kostornova, Tatyana Ya; Parfenova, Valentina V; Khodzher, Tamara V; Ahn, Tae-Seok; Zo, Young-Gun

    2012-02-01

    Biological entities and gradients of selected chemicals within the seemingly barren ice layers covering Lake Baikal were investigated. Ice cores 40-68 cm long were obtained from in shore and offshore sites of Southern Lake Baikal during the cold period of a year (March-April) in 2007 and 2008. In microscopic observations of the melted ice, both algae and bacteria were found in considerable numbers (>10(3) cells/L and >10(4) cells/ml, respectively). Among all organisms found, diatom was generally the most predominant taxon in the ice. Interestingly, both planktonic and benthic algae were present in considerable numbers (2-4×10(4) cells/L). Dominant phototrophic picoplankton were comprised of small green algae of various taxa and cyanobacteria of Synechococcus and Cyanobium. The bacterial community consisted mostly of short rod and cocci cells, either free-living or aggregated. Large numbers of yeast-like cells and actinomycete mycelium were also observed. Concentrations of silica, phosphorus, and nitrate were low by an order of magnitude where biota was abundant. The profile of the ice could be interpreted as vertical stratification of nutrients and biomass due to biological activities. Therefore, the organisms in the ice were regarded to maintain high activity while thriving under freezing conditions. Based on the results, it was concluded that the freshwater ice covering the surface of Lake Baikal is considerably populated by extremophilic microorganisms that actively metabolize and form a detritus food chain in the unique large freshwater ecosystem of Lake Baikal. PMID:22367932

  9. Magnitude and Spatio-Temporal Variability of Methane Export From a Seasonally Stratified, Eutrophic Lake

    NASA Astrophysics Data System (ADS)

    Varadharajan, C.; Hemond, H. F.

    2007-12-01

    Recent studies have suggested that significant amounts of methane can be released to the atmosphere from freshwater lakes, particularly through bubbling. Yet the relative importance of ebullition in the methane cycle of aquatic ecosystems is poorly understood, since it is a spatially and temporally heterogeneous process. The primary intent of this research is to measure the magnitude, rate and distribution of methane loss from lakes to the atmosphere due to both bubbling and diffusion, using the eutrophic Upper Mystic Lake in Massachusetts as a case study. Over the summer of 2007, under-water conical chambers were deployed to provide an estimate of bubbling fluxes, and the composition of the gases released in this process. Most of the bubbling occurred during short episodes with peak flux rates approaching 200 ml/m2/d, while average ebullition was approximately 30- 45 ml/m2/d. Spatial variability in fluxes was also observed - shallower locations had approximately 3 to 5 times less flux than deeper stations. The mixing ratio of methane present in the collected gas varied across stations and ranged from ~50% to 90%, except at some shallow locations where it was less than 10%. Concentrations of dissolved methane at the surface were less than 1uM leading to calculated rates of diffusive loss that are less than 20 ml/m2/d. This suggests that bubbling, rather than diffusion, is likely to be the more important pathway for methane release to the atmosphere.

  10. Remote sensing of the surface layer dynamics of a stratified lake

    NASA Astrophysics Data System (ADS)

    Steissberg, Todd Eugene

    Physical processes, such as upwelling, circulation, and small-scale eddies, affect aquatic ecosystem functioning, controlling nutrient and light availability and pollutant transport in inland and coastal waters. These processes can be characterized and tracked across time and space using a combination of thermal infrared and reflective-solar (visible light) satellite measurements. Thermal gradients, created and altered by physical processes, facilitate daytime and nighttime detection and tracking of upwelling fronts, surface jets, basin-scale gyres, and small-scale eddies. Similarly, sunglint patterns in reflective-solar satellite measurements are altered by internal waves, current shear, and rotation, improving delineation of fronts, jets, and eddies, and determination of transport direction or rotational characteristics. This study applied thermal infrared and reflective-solar satellite images and field measurements, collected across multiple spatial and temporal scales, to characterize upwelling, circulation, and eddies at Lake Tahoe, California-Nevada. This included developing a novel technique to improve the quality of moderate-resolution satellite temperature data, creating filtered, calibrated Water Skin Temperature (WST) maps that clearly delineate thermal features, while preserving nearshore data and temperature accuracy. Time series of filtered WST maps acquired by two moderate-resolution satellite sensors were used to track up-welling fronts and jets, which can recur at moderate wind speeds when wind forcing is in phase with internal wave motion. High-resolution temperature and sunglint maps were used to characterize several, small-scale "spiral eddies" at Lake Tahoe. These features, although common in the ocean, have not been documented before in lakes. Satellite measurements showed spiral eddies form along thermal fronts and shear zones at Lake Tahoe, rotating predominantly cyclonically, as in the ocean, with sub-inertial periods longer than 21 hours

  11. Seasonal distribution of organic matter and copper under stratified conditions in a karstic, marine, sulfide rich environment (Rogoznica Lake, Croatia)

    NASA Astrophysics Data System (ADS)

    Plavšić, Marta; Ciglenečki, Irena; Strmečki, Slađana; Bura-Nakić, Elvira

    2011-04-01

    Closed, isolated small systems, as the representatives of a "unique-environmental feature", are valuable natural laboratories for studying different biogeochemical processes. The saline Rogoznica Lake ("Dragon Eye"), situated on the Eastern Adriatic coast is such a system (10 276 m 2, 15 m deep) typical of many stratified, sulfide rich water bodies. The depth of mixolimnion changes seasonally and it is greatly influenced by meteorological conditions, i.e. temperature and rainfall. Vertical mixing usually occurs during winter when cold, oxygen-rich water from the surface sinks downwards. In 2009 we monitored seasonal distribution and variation of copper complexing capacity (L T), related apparent stability constants (K app), concentration of Cu 2+ ions, surfactant activity (SAS), dissolved organic carbon (DOC) and reduced sulfur species (RSS). Our results have shown that L T is increasing with depth up to 8 m depth, while the concentrations of copper ions decrease with the depth due to the higher amount of RSS species in deeper layers. The values of log K app are also decreasing with depth as a consequence of a competition of organic ligands and sulfide ions for binding Cu. Below 8 m depth the presence of high amounts of RSS (˜1 mM) influences the electrochemical measuring of copper ion and L T determination, contributing to the copper ion binding.

  12. Spatial distribution and risk assessment of heavy metals in sediments from a hypertrophic plateau lake Dianchi, China.

    PubMed

    Yuan, Zhang; Taoran, Shi; Yan, Zhang; Tao, Yu

    2014-02-01

    The sediment in Dianchi Lake, a hypereutrophic plateau lake in southwest China, was investigated and the concentration of heavy metals (Cu, Cr, Ni, Zn, Pb, Fe, Mn, and Cd) in the sediment and sediment properties were determined. Their spatial distribution and sources were analyzed using multivariate statistics. The result indicated that the studied metals exhibited three distinct spatial patterns; that is, Cu, Pb, Zn, and Ni had a similar distribution, with a concentration gradient from the north to the south part of the lake; Cd and Cr presented a similar distribution; Fe and Mn presented a quite different distribution than other metals, which indicated their different sources and geochemistry processes. Correlation and cluster analysis (CA) provided origin information on these metals and the CA result was observed corresponding to those three spatial patterns. Principal component analysis further displayed metal source and driving factors; that is, Cu, Pb, Zn, Ni, Cd, and Cr were mainly derived from anthropogenic sources, and Fe and Mn were mainly the result of natural processes. Sediment assessment was conducted using geoaccumulation index (Igeo), potential ecological risk indices, and USEPA guidelines. The result indicated that, generally, Cd was the most serious risk metal; Pb and Cu posed moderate potential ecological risk; Cr, Zn, and Ni had slight ecological risk; Fe and Mn had little risk. Comparison of the assessment tools showed that each of the methods had its limitation and could bias the result, and the combined use of the methodologies and local knowledge on lithology or metal background value of soil in the practice would give a more comprehensive understanding of the metal risk or pollution. Statistical analysis also indicated that nutrients had different impacts on Fe, Mn, and trace elements, which implied that in the assessment of metal risk, nutrients impact should be taken into consideration especially for eutrophic waters. PMID:24078143

  13. Hypertrophic pachymeningitis.

    PubMed

    Hahn, Lewis D; Fulbright, Robert; Baehring, Joachim M

    2016-08-15

    Hypertrophic Pachymeningitis (HP) denotes inflammation and thickening of the dura mater that can be idiopathic or secondary to a wide variety of conditions. Clinically, HP can present as debilitating headaches and cranial nerve defects but in other cases may be completely asymptomatic. We aimed to determine the relative incidence of different etiologies of HP and compare their associated imaging findings. Additionally, we sought to compare the clinical features of the underlying syndromes. We retrospectively examined twenty-two consecutive cases of HP seen in a single practitioner neurology practice over a ten-year time period. The most common etiologies were idiopathic HP and neurosarcoidosis. No imaging features were completely specific to any etiology. Nonetheless, idiopathic HP typically demonstrated diffuse regular enhancement whereas neurosarcoidosis was more likely to display a nodular enhancement pattern. Headache and cranial neuropathies were the most common clinical presentation. HP symptoms were often responsive to steroids but complete responses were rare. HP is a diagnostic challenge without specific findings on minimally or non-invasive diagnostic studies. Biopsy is often required and serves as the basis for effective therapy. PMID:27423604

  14. Depth profiles of spectral and hydrological characteristics of water and their relation to abundances of green sulfur bacteria in the stratified lakes of the White Sea

    NASA Astrophysics Data System (ADS)

    Kharcheva, Anastasia V.; Krasnova, Elena D.; Gorlenko, Vladimir M.; Lunina, Olga N.; Savvichev, Alexander S.; Voronov, Dmitry A.; Zhiltsova, Anna A.; Patsaeva, Svetlana V.

    2016-04-01

    We analyze the results received from two expeditions performed in August-September 2013, August-September 2014 and February 2015 in the Kandalaksha Bay of the White Sea. Depth profiles of hydrological characteristics and optical properties of water were recorded for five marine lakes being on different stages of isolation from the White Sea. Those relic lakes demonstrate a tendency to meromixis and are characterized by apparent stratification of the water bodies from the brackish top layer to the bottom salt water. Maximal concentrations of anoxygenic phototrophs (green sulfur bacteria) were found at depths close to the redox interface in all the studied lakes. To discriminate differently pigmented groups of microorganisms the fluorescence emission spectra of bacteriochlorophylls from the living cells were used. We puzzle out the data on light spectrum propagation through the water body in each lake using optical properties of water (attenuation spectra) in the UV, visible and NIR ranges, as well as direct measurements of the total irradiances at various depths. The changes in optical characteristics of water in the stratified reservoirs due to cromophoric dissolved organic matter (CDOM) and microbial pigments affect the light intensity and its spectral distribution at each water layer thus influencing the living conditions for differently pigmented phototrophic microorganisms and determining the composition of microbial community.

  15. Absorption and fluorescence of hydrophobic components of dissolved organic matter in several Karelian lakes with stratified structures

    NASA Astrophysics Data System (ADS)

    Khundzhua, Daria A.; Kharcheva, Anastasia V.; Krasnova, Elena D.; Gorshkova, Olga M.; Chevel, Kira A.; Yuzhakov, Viktor I.; Patsaeva, Svetlana V.

    2016-04-01

    Hydrophobic components of cromophoric dissolved organic matter (CDOM) extracted from water samples and sediments taken in several relic basins located on Karelian shoreline of the White Sea were analyzed using spectroscopic techniques. Those water reservoirs exist at various stages of isolation from the White Sea and represent complex stratified systems of fresh and marine water layers not completely mixing trough the year. Basins separating from the White Sea are the unique natural objects for investigations of properties CDOM, its transformation in the process of turning the marine ecosystem into freshwater environment. CDOM occurring in all types of natural water represents a significant reservoir of organic carbon and plays a key role in the carbon cycle on the Earth. However, aquatic CDOM and nonliving organic matter in sediments from relic separating basins still have not been studied. The target of this work was to study absorption and fluorescence spectra of hydrophobic components of aquatic CDOM from different water depth and sediments in several separated basins of the Kandalaksha Gulf of the White Sea located near the N.A. Pertsov White Sea Biological Station.

  16. Size and elemental distributions of nano- to micro-particulates in the geochemically-stratified Great Salt Lake

    USGS Publications Warehouse

    Diaz, X.; Johnson, W.P.; Fernandez, D.; Naftz, D.L.

    2009-01-01

    The characterization of trace elements in terms of their apportionment among dissolved, macromolecular, nano- and micro-particulate phases in the water column of the Great Salt Lake carries implications for the potential entry of toxins into the food web of the lake. Samples from the anoxic deep and oxic shallow brine layers of the lake were fractionated using asymmetric flow field-flow fractionation (AF4). The associated trace elements were measured via online collision cell inductively-coupled plasma mass spectrometry (CC-ICP-MS). Results showed that of the total (dissolved + particulate) trace element mass, the percent associated with particulates varied from negligible (e.g. Sb), to greater than 50% (e.g. Al, Fe, Pb). Elements such as Cu, Zn, Mn, Co, Au, Hg, and U were associated with nanoparticles, as well as being present as dissolved species. Particulate-associated trace elements were predominantly associated with particulates larger than 450 nm in size. Among the smaller nanoparticulates (<450 nm), some trace elements (Ni, Zn, Au and Pb) showed higher percent mass (associated with nanoparticles) in the 0.9-7.5 nm size range relative to the 10-250 nm size range. The apparent nanoparticle size distributions were similar between the two brine layers; whereas, important differences in elemental associations to nanoparticles were discerned between the two layers. Elements such as Zn, Cu, Pb and Mo showed increasing signal intensities from oxic shallow to anoxic deep brine, suggesting the formation of sulfide nanoparticles, although this may also reflect association with dissolved organic matter. Aluminum and Fe showed greatly increased concentration with depth and equivalent size distributions that differed from those of Zn, Cu, Pb and Mo. Other elements (e.g. Mn, Ni, and Co) showed no significant change in signal intensity with depth. Arsenic was associated with <2 nm nanoparticles, and showed no increase in concentration with depth, possibly indicating

  17. Density-stratified flow events in Great Salt Lake, Utah, USA: implications for mercury and salinity cycling

    USGS Publications Warehouse

    Naftz, David L.; Carling, Gregory T.; Angeroth, Cory; Freeman, Michael; Rowland, Ryan; Pazmiño, Eddy

    2014-01-01

    Density stratification in saline and hypersaline water bodies from throughout the world can have large impacts on the internal cycling and loading of salinity, nutrients, and trace elements. High temporal resolution hydroacoustic and physical/chemical data were collected at two sites in Great Salt Lake (GSL), a saline lake in the western USA, to understand how density stratification may influence salinity and mercury (Hg) distributions. The first study site was in a causeway breach where saline water from GSL exchanges with less saline water from a flow restricted bay. Near-surface-specific conductance values measured in water at the breach displayed a good relationship with both flow and wind direction. No diurnal variations in the concentration of dissolved (total and MeHg loadings was observed during periods of elevated salinity. The second study site was located on the bottom of GSL where movement of a high-salinity water layer, referred to as the deep brine layer (DBL), is restricted to a naturally occurring 1.5-km-wide “spillway” structure. During selected time periods in April/May, 2012, wind-induced flow reversals in a railroad causeway breach, separating Gunnison and Gilbert Bays, were coupled with high-velocity flow pulses (up to 55 cm/s) in the DBL at the spillway site. These flow pulses were likely driven by a pressure response of highly saline water from Gunnison Bay flowing into the north basin of Gilbert Bay. Short-term flow reversal events measured at the railroad causeway breach have the ability to move measurable amounts of salt and Hg from Gunnison Bay into the DBL. Future disturbance to the steady state conditions currently imposed by the railroad causeway infrastructure could result in changes to the existing chemical balance between Gunnison and Gilbert Bays. Monitoring instruments were installed at six additional sites in the DBL during October 2012 to assess impacts from any future modifications to the railroad causeway.

  18. [Hypertrophic cardiomyopathy. Arrhythmia in hypertrophic cardiomyopathy].

    PubMed

    Colín Lizalde, Luis de Jesús

    2003-01-01

    Hypertrophic cardiomyopathy is a relatively common genetic disorder with heterogeneity in mutations, forms of presentation, prognosis and treatment strategies. Hypertrophic cardiomyopathy is recognized as the most common cause of sudden cardiac death that occurs in young people, including athletes. The clinical diagnosis is complemented with the ecocardiographic study, in which an abnormal myocardial hypertrophy of the septum can be observed in the absence of a cardiac or systemic disease (arterial systemic hypertension, aortic stenosis). The annual sudden mortality rate is 1% and, in selected populations, it ranges between 3 and 6%. The therapeutic strategies depend on the different subsets of patients according to the morbidity and mortality, sudden cardiac death, obstructive symptoms, heart failure or atrial fibrillation and stroke. High risk patients for sudden death may effectively be treated with the automatic implantable cardioverter-defibrillator. PMID:12966640

  19. Biological activity at the limits of life: Microbial cycling of C, S and N in cold, permanently stratified, hypersaline Lake Vanda, Antarctica.

    NASA Astrophysics Data System (ADS)

    Joye, S. B.; Schutte, C.; Samarkin, V.; Casciotti, K. L.; Madigan, M.; Saxton, M.

    2014-12-01

    The lakes of the McMurdo Dry Valleys (MCM) are the only perennially ice covered lakes on Earth and are the primary refuge for life in this hyper-arid polar desert. As a result of the ice cover and an uncoupled day/night cycle, the physical and biogeochemical processes in the lakes are highly unusual, with biogeochemical gradients and concentrations of specific compounds often exceeding those found in other aquatic ecosystems on Earth. These lakes are ideal systems for the study of redox-sensitive biogeochemical processes, model systems for understanding the effects of global climate change on polar ecosystems, end-member systems that provide insight into biogeochemical and limnological dynamics in meromictic lakes, analogues for life on other planets, and perfect systems to study microbial life at its thermodynamic limits. Lake Vanda, in the Wright valley, is relatively deep (73 m), hypersaline and has anoxic bottom water. High concentrations of chacotrophic salts results in low water activities that exert further challenges on microbial life. We collected details geochemical profiles of nutrients, major ions, dissolved gases, and redox metabolites and measured rates of microbially-mediated processes that cycle carbon, nitrogen and sulfur in the lakes waters and sediments. Despite the harsh and extreme nature of Lake Vanda and the thermodynamic barriers to microbially-mediated geochemical reactions, microorganisms are not only present in the lake but they mediate a diverse suite of geochemical processes. Statistical correlations between geochemical parameters, microbial activity and microbial community composition shed light on the factors that regulate and limit microbial activity in this unique extreme environment.

  20. Hypertrophic Cardiomyopathy: A Review

    PubMed Central

    Houston, Brian A; Stevens, Gerin R

    2014-01-01

    Hypertrophic cardiomyopathy (HCM) is a global disease with cases reported in all continents, affecting people of both genders and of various racial and ethnic origins. Widely accepted as a monogenic disease caused by a mutation in 1 of 13 or more sarcomeric genes, HCM can present catastrophically with sudden cardiac death (SCD) or ventricular arrhythmias or insidiously with symptoms of heart failure. Given the velocity of progress in both the fields of heart failure and HCM, we present a review of the approach to patients with HCM, with particular attention to those with HCM and the clinical syndrome of heart failure. PMID:25657602

  1. A hydrodynamics-based approach to evaluating the risk of waterborne pathogens entering drinking water intakes in a large, stratified lake.

    PubMed

    Hoyer, Andrea B; Schladow, S Geoffrey; Rueda, Francisco J

    2015-10-15

    Pathogen contamination of drinking water lakes and reservoirs is a severe threat to human health worldwide. A major source of pathogens in surface sources of drinking waters is from body-contact recreation in the water body. However, dispersion pathways of human waterborne pathogens from recreational beaches, where body-contact recreation is known to occur to drinking water intakes, and the associated risk of pathogens entering the drinking water supply remain largely undocumented. A high spatial resolution, three-dimensional hydrodynamic and particle tracking modeling approach has been developed to analyze the risk and mechanisms presented by pathogen dispersion. The pathogen model represents the processes of particle release, transport and survival. Here survival is a function of both water temperature and cumulative exposure to ultraviolet (UV) radiation. Pathogen transport is simulated using a novel and computationally efficient technique of tracking particle trajectories backwards, from a drinking water intake toward their source areas. The model has been applied to a large, alpine lake - Lake Tahoe, CA-NV (USA). The dispersion model results reveal that for this particular lake (1) the risk of human waterborne pathogens to enter drinking water intakes is low, but significant; (2) this risk is strongly related to the depth of the thermocline in relation to the depth of the intake; (3) the risk increases with the seasonal deepening of the surface mixed layer; and (4) the risk increases at night when the surface mixed layer deepens through convective mixing and inactivation by UV radiation is eliminated. While these risk factors will quantitatively vary in different lakes, these same mechanisms will govern the process of transport of pathogens. PMID:26162312

  2. Update on hypertrophic scar treatment.

    PubMed

    Rabello, Felipe Bettini; Souza, Cleyton Dias; Farina Júnior, Jayme Adriano

    2014-08-01

    Scar formation is a consequence of the wound healing process that occurs when body tissues are damaged by a physical injury. Hypertrophic scars and keloids are pathological scars resulting from abnormal responses to trauma and can be itchy and painful, causing serious functional and cosmetic disability. The current review will focus on the definition of hypertrophic scars, distinguishing them from keloids and on the various methods for treating hypertrophic scarring that have been described in the literature, including treatments with clearly proven efficiency and therapies with doubtful benefits. Numerous methods have been described for the treatment of abnormal scars, but to date, the optimal treatment method has not been established. This review will explore the differences between different types of nonsurgical management of hypertrophic scars, focusing on the indications, uses, mechanisms of action, associations and efficacies of the following therapies: silicone, pressure garments, onion extract, intralesional corticoid injections and bleomycin. PMID:25141117

  3. Update on hypertrophic scar treatment

    PubMed Central

    Rabello, Felipe Bettini; Souza, Cleyton Dias; Júnior, Jayme Adriano Farina

    2014-01-01

    Scar formation is a consequence of the wound healing process that occurs when body tissues are damaged by a physical injury. Hypertrophic scars and keloids are pathological scars resulting from abnormal responses to trauma and can be itchy and painful, causing serious functional and cosmetic disability. The current review will focus on the definition of hypertrophic scars, distinguishing them from keloids and on the various methods for treating hypertrophic scarring that have been described in the literature, including treatments with clearly proven efficiency and therapies with doubtful benefits. Numerous methods have been described for the treatment of abnormal scars, but to date, the optimal treatment method has not been established. This review will explore the differences between different types of nonsurgical management of hypertrophic scars, focusing on the indications, uses, mechanisms of action, associations and efficacies of the following therapies: silicone, pressure garments, onion extract, intralesional corticoid injections and bleomycin. PMID:25141117

  4. Lake

    ERIC Educational Resources Information Center

    Wien, Carol Anne

    2008-01-01

    The lake is blue black and deep. It is a glaciated finger lake, clawed out of rock when ice retracted across Nova Scotia in a northerly direction during the last ice age. The lake is narrow, a little over a mile long, and deep, 90 to 190 feet in places according to local lore, off the charts in others. The author loves to swim there, with a sense…

  5. Geohydrology, water quality, and simulation of groundwater flow in the stratified-drift aquifer system in Virgil Creek and Dryden Lake Valleys, Town of Dryden, Tompkins County, New York

    USGS Publications Warehouse

    Miller, Todd S.; Bugliosi, Edward F.

    2013-01-01

    In 2002, the U.S. Geological Survey, in cooperation with the Tompkins County Planning Department and the Town of Dryden, New York, began a study of the stratified-drift aquifer system in the Virgil Creek and Dryden Lake Valleys in the Town of Dryden, Tompkins County. The study provided geohydrologic data needed by the town and county to develop a strategy to manage and protect their water resources. In this study area, three extensive confined sand and gravel aquifers (the upper, middle, and lower confined aquifers) compose the stratified-drift aquifer system. The Dryden Lake Valley is a glaciated valley oriented parallel to the direction of ice movement. Erosion by ice extensively widened and deepened the valley, truncated bedrock hillsides, and formed a nearly straight, U-shaped bedrock trough. The maximum thickness of the valley fill in the central part of the valley is about 400 feet (ft). The Virgil Creek Valley in the east part of the study area underwent less severe erosion by ice than the Dryden Lake Valley, and hence, it has a bedrock floor that is several hundred feet higher in altitude than that in the Dryden Lake Valley. The sources and amounts of recharge were difficult to identify in most areas because the confined aquifers are overlain by confining units. However, in the vicinity of the Virgil Creek Dam, the upper confined aquifer crops out at land surface in the floodplain of a gorge eroded by Virgil Creek, and this is where the aquifer receives large amounts of recharge from precipitation that directly falls over the aquifer and from seepage losses from Virgil Creek. The results of streamflow measurements made in Virgil Creek where it flows through the gorge indicated that the stream lost 1.2 cubic feet per second (ft3/s) or 0.78 million gallons per day (Mgal/d) of water in the reach extending from 220 ft downstream from the dam to 1,200 ft upstream from the dam. In the southern part of the study area, large amounts of recharge also replenish the

  6. Burns, hypertrophic scar and galactorrhea.

    PubMed

    Karimi, Hamid; Nourizad, Samad; Momeni, Mahnoush; Rahbar, Hosein; Momeni, Mazdak; Farhadi, Khosro

    2013-07-01

    An 18-year-old woman was admitted to Motahari Burn Center suffering from 30% burns. Treatment modalities were carried out for the patient and she was discharged after 20 days. Three to four months later she developed hypertrophic scar on her chest and upper limbs. At the same time she developed galactorrhea in both breasts and had a disturbed menstrual cycle four months post-burn. On investigation, we found hyperprolactinemia and no other reasons for the high level of prolactin were detected.She received treatment for both the hypertrophic scar and the severe itching she was experiencing. After seven months, her prolactin level had decreased but had not returned to the normal level. It seems that refractory hypertrophic scar is related to the high level of prolactin in burns patients. PMID:23456048

  7. Topical treatments for hypertrophic scars.

    PubMed

    Zurada, Joanna M; Kriegel, David; Davis, Ira C

    2006-12-01

    Hypertrophic scars represent an abnormal, exaggerated healing response after skin injury. In addition to cosmetic concern, scars may cause pain, pruritus, contractures, and other functional impairments. Therapeutic modalities include topical medications, intralesional corticosteroids, laser therapy, and cryosurgery. Topical therapies, in particular, have become increasingly popular because of their ease of use, comfort, noninvasiveness, and relatively low cost. This review will discuss the properties and effectiveness of these agents, including pressure therapy, silicone gel sheeting and ointment, polyurethane dressing, onion extract, imiquimod 5% cream, and vitamins A and E in the prevention and treatment of hypertrophic scars. PMID:17097399

  8. Stable isotope and hydrogeochemical studies of Beaver Lake and Radok Lake, MacRobertson Land, East Antarctica.

    PubMed

    Wand, Ulrich; Hermichen, Wolf-Dieter; Brüggemann, Erika; Zierath, Reinhard; Klokov, Valerii Dmitrievich

    2011-12-01

    Beaver Lake and Radok Lake, the largest known epishelf lake and the deepest freshwater lake on the Antarctic continent, respectively, were isotopically (δ(2)H, δ(18)O) and hydrogeochemically studied. Radok Lake is an isothermal and non-stratified, i.e. homogeneous water body, while Beaver Lake is stratified with respect to temperature, salinity, and isotopic composition. The results for the latter attest to freshwater (derived from snow and glacier melt) overlying seawater. PMID:22092172

  9. Laser application for hypertrophic rhinitis

    NASA Astrophysics Data System (ADS)

    Inouye, Tetsuzo; Tanabe, Tetsuya; Nakanoboh, Manabu; Ogura, Masami

    1995-05-01

    The CO2 and KTP/532 lasers have been used in the treatment of an allergic and hypertrophic rhinitis for the past several years. As we know, the laser enables a surgeon to perform the operation with minimum hemorrhage and minimized pain, during and after the procedure. Additionally many of these operations can be performed under local anesthesia instead of general anesthesia, on an outpatient basis. The laser is used to irradiate the mucous membranes of the inferior turbinates. Vaporization and cutting is easily done. Post operative management of the local operated area is easy. The advantages of laser surgery over regular surgical techniques are supreme for intranasal operations when performed under local anesthesia.

  10. Subaortic membrane mimicking hypertrophic cardiomyopathy.

    PubMed

    Anderson, Mark Joseph; Arruda-Olson, Adelaide; Gersh, Bernard; Geske, Jeffrey

    2015-01-01

    A 34-year-old man was referred for progressive angina and exertional dyspnoea refractory to medical therapy, with a presumptive diagnosis of hypertrophic cardiomyopathy (HCM). Transthoracic echocardiography (TTE) revealed asymmetric septal hypertrophy without systolic anterior motion of the mitral valve leaflet and with no dynamic left ventricular outflow tract (LVOT) obstruction. However, the LVOT velocity was elevated at rest as well as with provocation, without the characteristic late peaking obstruction seen in HCM. Focused TTE to evaluate for suspected fixed obstruction demonstrated a subaortic membrane 2.2 cm below the aortic valve. Coronary CT angiography confirmed the presence of the subaortic membrane and was negative for concomitant coronary artery disease. Surgical resection of the subaortic membrane and septal myectomy resulted in significant symptomatic relief and lower LVOT velocities on postoperative TTE. This case reminds the clinician to carefully evaluate for alternative causes of LVOT obstruction, especially subaortic membrane, as a cause of symptoms mimicking HCM. PMID:26538250

  11. Experimental Therapies in Hypertrophic Cardiomyopathy

    PubMed Central

    Marian, Ali J.

    2010-01-01

    The quintessential clinical diagnostic phenotype of human hypertrophic cardiomyopathy (HCM) is primary cardiac hypertrophy. Cardiac hypertrophy is also a major determinant of mortality and morbidity including the risk of sudden cardiac death (SCD) in patients with HCM. Reversal and attenuation of cardiac hypertrophy and its accompanying fibrosis is expected to improve morbidity as well as decrease the risk of SCD in patients with HCM. The conventionally used pharmacological agents in treatment of patients with HCM have not been shown to reverse or attenuate established cardiac hypertrophy and fibrosis. An effective treatment of HCM has to target the molecular mechanisms that are involved in the pathogenesis of the phenotype. Mechanistic studies suggest that cardiac hypertrophy in HCM is secondary to activation of various hypertrophic signaling molecules and, hence, is potentially reversible. The hypothesis is supported by the results of genetic and pharmacological interventions in animal models. The results have shown potential beneficial effects of angiotensin II receptor blocker losartan, mineralocorticoid receptor blocker spironolactone, 3-hydroxy-3-methyglutaryl-coenzyme A reductase inhibitors simvastatin and atorvastatin, and most recently, N-acetylcysteine (NAC) on reversal or prevention of hypertrophy and fibrosis in HCM. The most promising results have been obtained with NAC, which through multiple thiol-responsive mechanisms completely reversed established cardiac hypertrophy and fibrosis in three independent studies. Pilot studies with losartan and statins in humans have established the feasibility of such studies. The results in animal models have firmly established the reversibility of established cardiac hypertrophy and fibrosis in HCM and have set the stage for advancing the findings in the animal models to human patients with HCM through conducting large-scale efficacy studies. PMID:20560006

  12. Stably stratified building wakes

    SciTech Connect

    Kothari, K.M.; Peterka, J.A.; Meroney, R.N.

    1980-01-01

    The velocity and temperature wake behind an isolated building placed in a stably stratified turbulent boundary layer has been investigated utilizing wind tunnel tests and mathematical analysis. The mean velocity and mean temperature decrease but turbulence intensity and temperature fluctuation intensity increase as a result of the momentum wake. However, the vortex wake increases mean velocity and mean temperature, and decreases turbulence intensity and temperature fluctuation intensity along the centerline of the wake.

  13. Hypertrophic pachymeningitis accompanying neuromyelitis optica spectrum disorder: A case report.

    PubMed

    Kon, Tomoya; Nishijima, Haruo; Haga, Rie; Funamizu, Yukihisa; Ueno, Tatsuya; Arai, Akira; Suzuki, Chieko; Nunomura, Jin-ichi; Baba, Masayuki; Takahashi, Toshiyuki; Tomiyama, Masahiko

    2015-10-15

    We report a case of idiopathic cerebral hypertrophic pachymeningitis accompanying neuromyelitis optica spectrum disorder. No other identifiable cause of pachymeningitis was detected. Corticosteroid therapy was effective for both diseases. Hypertrophic pachymeningitis is closely related to autoimmune inflammatory disease of the central nervous system. This case supports the hypothesis that hypertrophic pachymeningitis can be a rare comorbidity of neuromyelitis optica spectrum disorder. PMID:26439957

  14. Stratified vapor generator

    DOEpatents

    Bharathan, Desikan; Hassani, Vahab

    2008-05-20

    A stratified vapor generator (110) comprises a first heating section (H.sub.1) and a second heating section (H.sub.2). The first and second heating sections (H.sub.1, H.sub.2) are arranged so that the inlet of the second heating section (H.sub.2) is operatively associated with the outlet of the first heating section (H.sub.1). A moisture separator (126) having a vapor outlet (164) and a liquid outlet (144) is operatively associated with the outlet (124) of the second heating section (H.sub.2). A cooling section (C.sub.1) is operatively associated with the liquid outlet (144) of the moisture separator (126) and includes an outlet that is operatively associated with the inlet of the second heating section (H.sub.2).

  15. Aortic biomechanics in hypertrophic cardiomyopathy

    PubMed Central

    Badran, Hala Mahfouz; Soltan, Ghada; Faheem, Nagla; Elnoamany, Mohamed Fahmy; Tawfik, Mohamed; Yacoub, Magdi

    2015-01-01

    Background: Ventricular-vascular coupling is an important phenomenon in many cardiovascular diseases. The association between aortic mechanical dysfunction and left ventricular (LV) dysfunction is well characterized in many disease entities, but no data are available on how these changes are related in hypertrophic cardiomyopathy (HCM). Aim of the work: This study examined whether HCM alone is associated with an impaired aortic mechanical function in patients without cardiovascular risk factors and the relation of these changes, if any, to LV deformation and cardiac phenotype. Methods: 141 patients with HCM were recruited and compared to 66 age- and sex-matched healthy subjects as control group. Pulse pressure, aortic strain, stiffness and distensibility were calculated from the aortic diameters measured by M-mode echocardiography and blood pressure obtained by sphygmomanometer. Aortic wall systolic and diastolic velocities were measured using pulsed wave Doppler tissue imaging (DTI). Cardiac assessment included geometric parameters and myocardial deformation (strain and strain rate) and mechanical dyssynchrony. Results: The pulsatile change in the aortic diameter, distensibility and aortic wall systolic velocity (AWS') were significantly decreased and aortic stiffness index was increased in HCM compared to control (P < .001) In HCM AWS' was inversely correlated to age(r = − .32, P < .0001), MWT (r = − .22, P < .008), LVMI (r = − .20, P < .02), E/Ea (r = − .16, P < .03) LVOT gradient (r = − 19, P < .02) and severity of mitral regurg (r = − .18, P < .03) but not to the concealed LV deformation abnormalities or mechanical dyssynchrony. On multivariate analysis, the key determinant of aortic stiffness was LV mass index and LVOT obstruction while the role LV dysfunction in aortic stiffness is not evident in this population. Conclusion: HCM is associated with abnormal aortic mechanical properties. The severity of cardiac

  16. Infective endocarditis in hypertrophic cardiomyopathy

    PubMed Central

    Dominguez, Fernando; Ramos, Antonio; Bouza, Emilio; Muñoz, Patricia; Valerio, Maricela C.; Fariñas, M. Carmen; de Berrazueta, José Ramón; Zarauza, Jesús; Pericás Pulido, Juan Manuel; Paré, Juan Carlos; de Alarcón, Arístides; Sousa, Dolores; Rodriguez Bailón, Isabel; Montejo-Baranda, Miguel; Noureddine, Mariam; García Vázquez, Elisa; Garcia-Pavia, Pablo

    2016-01-01

    Abstract Infective endocarditis (IE) complicating hypertrophic cardiomyopathy (HCM) is a poorly known entity. Although current guidelines do not recommend IE antibiotic prophylaxis (IEAP) in HCM, controversy remains. This study sought to describe the clinical course of a large series of IE HCM and to compare IE in HCM patients with IE patients with and without an indication for IEAP. Data from the GAMES IE registry involving 27 Spanish hospitals were analyzed. From January 2008 to December 2013, 2000 consecutive IE patients were prospectively included in the registry. Eleven IE HCM additional cases from before 2008 were also studied. Clinical, microbiological, and echocardiographic characteristics were analyzed in IE HCM patients (n = 34) and in IE HCM reported in literature (n = 84). Patients with nondevice IE (n = 1807) were classified into 3 groups: group 1, HCM with native-valve IE (n = 26); group 2, patients with IEAP indication (n = 696); group 3, patients with no IEAP indication (n = 1085). IE episode and 1-year follow-up data were gathered. One-year mortality in IE HCM was 42% in our study and 22% in the literature. IE was more frequent, although not exclusive, in obstructive HCM (59% and 74%, respectively). Group 1 exhibited more IE predisposing factors than groups 2 and 3 (62% vs 40% vs 50%, P < 0.01), and more previous dental procedures (23% vs 6% vs 8%, P < 0.01). Furthermore, Group 1 experienced a higher incidence of Streptococcus infections than Group 2 (39% vs 22%, P < 0.01) and similar to Group 3 (39% vs 30%, P = 0.34). Overall mortality was similar among groups (42% vs 36% vs 35%, P = 0.64). IE occurs in HCM patients with and without obstruction. Mortality of IE HCM is high but similar to patients with and without IEAP indication. Predisposing factors, previous dental procedures, and streptococcal infection are higher in IE HCM, suggesting that HCM patients could benefit from IEAP. PMID:27368014

  17. Hypertrophic Cardiomyopathy in Athletes: Catching a Killer.

    ERIC Educational Resources Information Center

    Maron, Barry J.

    1993-01-01

    A leading cause of sudden death among young athletes, hypertrophic cardiomyopathy (HCM) does not always present cardiac signs and symptoms. Echocardiography offers the most effective means for diagnosis. Some patients require pharmaceutical or surgical intervention. Patients with HCM should not engage in organized competitive sports or…

  18. Low deuterium content of Lake Vanda, Antarctica

    USGS Publications Warehouse

    Ragotzkie, R.A.; Friedman, I.

    1965-01-01

    Lake Vanda in Victoria Land, Antarctica, is permanently ice-covered and permanently stratified, with warm, salty water near the bottom. Deuterium analyses of lake water from several levels indicate that the lake has a low deuterium content, and that it is stratified with respect to this isotope. This low deuterium content supports the evidence from the lake's ionic content that the saline layer is not of marine origin, and it indicates that evaporation from the ice surface has taken place. The stratification of the lake with respect to deuterium suggests that the upper and lower layers of water were formed at different times from different sources of glacial melt water.

  19. Turbulent vortices in stratified fluids

    NASA Technical Reports Server (NTRS)

    Hecht, A. M.; Bilanin, A. J.; Hirsh, J. E.; Snedeker, R. S.

    1979-01-01

    In the present paper, calculations, made with the finite difference axisymmetric WAKE computer code, of the influence of turbulence and stratification on the behavior of vortex rings are compared with experimental data. Calculations, made with the two-dimensional version of the code, are used to study the behavior of vortex pairs in stably stratified atmospheres for a range of Froude numbers. Stratification is shown to have a profound effect on the radius of a vortex ring descending into a stably stratified fluid. The separation of the vortices of a vortex pair remains nearly constant or decreases monotonically with increasing penetration of a stably stratified fluid, depending on whether the stratification is discontinuous or linear. An analysis based on an energy balance is used to assess the maximum descent of a vortex pair in a stably stratified fluid.

  20. Laparoscopic management of infantile hypertrophic pyloric stenosis.

    PubMed

    Gogolja, D; Visnjić, S; Maldini, B; Radesić, L; Roić, G; Zganjer, M; Fattorini, I

    2001-01-01

    Infantile hypertrophic pyloric stenosis is a common problem in pediatric surgery. Conventional management by the upper laparotomy was the method of choice over the last few decades. Advanced minimally invasive surgery allows successful endoscopic management of this entity too. We report on our initial experience with endoscopic surgery in the treatment of infantile hypertrophic pyloric stenosis with respect to some technical details. The operative procedure was well tolerated by the infant. After a short and uneventful postoperative course, the infant regained eating habits and was discharged from the hospital on the fifth postoperative day. Our favourable initial experience suggests that laparoscopic pyloromyotomy could be a safe and efficient alternative to the open surgery. PMID:11428282

  1. Apical hypertrophic cardiomyopathy presenting as acute coronary syndrome.

    PubMed

    Abdin, Amr; Eitel, Ingo; de Waha, Suzanne; Thiele, Holger

    2016-06-01

    Apical hypertrophic cardiomyopathy is a rare variant of hypertrophic cardiomyopathy. It is characterized by a local hypertrophy of the apical segments and displays typical electrocardiographic and imaging patterns. The clinical manifestations are variable and range from an asymptomatic course to sudden cardiac death. The most frequent symptom is chest pain and thus apical hypertrophic cardiomyopathy can mimic the symptoms and repolarization disturbances indicative of acute coronary syndrome. PMID:26628684

  2. Primary hypertrophic osteoarthropathy: ultrasound and MRI findings.

    PubMed

    Adams, Brook; Amin, Tania; Leone, Valentina; Wood, Mark; Kraft, Jeannette K

    2016-05-01

    Primary hypertrophic osteoarthropathy is a rare genetic disorder related to failures in prostaglandin metabolism. Patients present with joint pain, limb enlargement, skin thickening and finger clubbing. Radiographs show characteristic periosteal reaction and thickening along the long bones. We present MRI and US findings in a child with the condition. Ultrasound showed echogenic tissue surrounding the long bones, presumably reflecting oedema and inflammatory tissue. Doppler sonograms demonstrated increased vascularity on the surface of some superficial bony structures. PMID:26939972

  3. Pathological features of hypertrophic obstructive cardiomyopathy

    PubMed Central

    Davies, M. J.; Pomerance, Ariela; Teare, R. D.

    1974-01-01

    The macroscopic features of hypertrophic obstructive cardiomyopathy are variable. The most easily recognized picture is of disproportionate and asymmetrical left ventricular hypertrophy with a small ventricular volume. Symmetrical ventricular hypertrophy also occurs and dilatation of the ventricular cavity may lead to a configuration more usually associated with congestive cardiomyopathy. Papillary muscle involvement leads to a bullet shape, often retained even when the ventricle dilates. Eighteen of the hearts showed a distinctive band of fibrous thickening below the aortic valve. This was a mirror image of the free edge of the anterior mitral cusp, had the microscopic features of an endocardial friction lesion, and was clearly the morphological expression of the systolic contact between cusp and septum seen on cineangiography. This band is characteristic of hypertrophic obstructive cardiomyopathy; it was more common in older patients and is of particular diagnostic value in cases with symmetrical hypertrophy, including those with dilated ventricular cavities. Sudden death was the commonest presentation in the younger cases but in several cases over 60 years at death hypertrophic obstructive cardiomyopathy was an incidental necropsy finding. Images PMID:4472994

  4. The embryological basis of subclinical hypertrophic cardiomyopathy.

    PubMed

    Captur, Gabriella; Ho, Carolyn Y; Schlossarek, Saskia; Kerwin, Janet; Mirabel, Mariana; Wilson, Robert; Rosmini, Stefania; Obianyo, Chinwe; Reant, Patricia; Bassett, Paul; Cook, Andrew C; Lindsay, Susan; McKenna, William J; Mills, Kevin; Elliott, Perry M; Mohun, Timothy J; Carrier, Lucie; Moon, James C

    2016-01-01

    Hypertrophic cardiomyopathy (HCM) is caused by mutations in sarcomeric proteins, the commonest being MYBPC3 encoding myosin-binding protein C. It is characterised by left ventricular hypertrophy but there is an important pre-hypertrophic phenotype with features including crypts, abnormal mitral leaflets and trabeculae. We investigated these during mouse cardiac development using high-resolution episcopic microscopy. In embryonic hearts from wildtype, homozygous (HO) and heterozygous (HET) Mybpc3-targeted knock-out (KO) mice we show that crypts (one or two) are a normal part of wildtype development but they almost all resolve by birth. By contrast, HO and HET embryos had increased crypt presence, abnormal mitral valve formation and alterations in the compaction process. In scarce normal human embryos, crypts were sometimes present. This study shows that features of the human pre-hypertrophic HCM phenotype occur in the mouse. In an animal model we demonstrate that there is an embryological HCM phenotype. Crypts are a normal part of cardiac development but, along with the mitral valve and trabeculae, their developmental trajectory is altered by the presence of HCM truncating Mybpc3 gene mutation. PMID:27323879

  5. The embryological basis of subclinical hypertrophic cardiomyopathy

    PubMed Central

    Captur, Gabriella; Ho, Carolyn Y.; Schlossarek, Saskia; Kerwin, Janet; Mirabel, Mariana; Wilson, Robert; Rosmini, Stefania; Obianyo, Chinwe; Reant, Patricia; Bassett, Paul; Cook, Andrew C.; Lindsay, Susan; McKenna, William J.; Mills, Kevin; Elliott, Perry M.; Mohun, Timothy J.; Carrier, Lucie; Moon, James C.

    2016-01-01

    Hypertrophic cardiomyopathy (HCM) is caused by mutations in sarcomeric proteins, the commonest being MYBPC3 encoding myosin-binding protein C. It is characterised by left ventricular hypertrophy but there is an important pre-hypertrophic phenotype with features including crypts, abnormal mitral leaflets and trabeculae. We investigated these during mouse cardiac development using high-resolution episcopic microscopy. In embryonic hearts from wildtype, homozygous (HO) and heterozygous (HET) Mybpc3-targeted knock-out (KO) mice we show that crypts (one or two) are a normal part of wildtype development but they almost all resolve by birth. By contrast, HO and HET embryos had increased crypt presence, abnormal mitral valve formation and alterations in the compaction process. In scarce normal human embryos, crypts were sometimes present. This study shows that features of the human pre-hypertrophic HCM phenotype occur in the mouse. In an animal model we demonstrate that there is an embryological HCM phenotype. Crypts are a normal part of cardiac development but, along with the mitral valve and trabeculae, their developmental trajectory is altered by the presence of HCM truncating Mybpc3 gene mutation. PMID:27323879

  6. Inflammation and cutaneous nervous system involvement in hypertrophic scarring

    PubMed Central

    Li, Shao-hua; Yang, Heng-lian; Xiao, Hu; Wang, Yi-bing; Wang, De-chang; Huo, Ran

    2015-01-01

    This study aimed to use a mouse model of hypertrophic scarring by mechanical loading on the dorsum of mice to determine whether the nervous system of the skin and inflammation participates in hypertrophic scarring. Results of hematoxylin-eosin and immunohistochemical staining demonstrated that inflammation contributed to the formation of a hypertrophic scar and increased the nerve density in scar tissue.Western blot assay verified that interleukin-13 expression was increased in scar tissue. These findings suggest that inflammation and the cutaneous nervous system play a role in hypertrophic scar formation. PMID:26692869

  7. Right ventricular obstruction in various types of hypertrophic cardiomyopathy.

    PubMed

    Stierle, U; Sheikhzadeh, A; Shakibi, J G; Langbehn, A F; Diederich, K W

    1987-01-01

    Hypertrophic cardiomyopathy (HCM) is most probably a genetically transmitted disease with different clinical and hemodynamic features. In hypertrophic obstructive cardiomyopathy (HOCM) the obstruction is predominantly in the left ventricular outflow tract (IHSS). In a minority of cases the obstruction is strictly located in midventricle (midventricular obstruction, MO). Hypertrophic nonobstructive cardiomyopathy (HNCM) includes asymmetric septal hypertrophy (ASH) and apical hypertrophy (AH). Right ventricular hypertrophic obstruction (RVHO) is an uncommon type of HCM and is almost always combined with other types of left ventricular HCM. We describe in the present report 1 case of RVHO with IHSS, 2 cases with MO and, to our knowledge, the first case with AH. PMID:3599397

  8. CHEMISTRY OF WILDERNESS LAKES IN THE WESTERN UNITED STATES

    EPA Science Inventory

    A synopic survey of 719 lakes representing over 10,000 lakes in mountainous areas of the western U.S. was conducted in autumn 1985. Nearly two-thirds of the study lakes were located in wilderness areas or national parks. The lake selection process employed a stratified design wit...

  9. Occurrence of Clinically Diagnosed Hypertrophic Cardiomyopathy in the United States.

    PubMed

    Maron, Martin S; Hellawell, Jennifer L; Lucove, Jaime C; Farzaneh-Far, Ramin; Olivotto, Iacopo

    2016-05-15

    Hypertrophic cardiomyopathy (HC) is the most common genetic heart disease and an important cause of sudden death and heart failure symptoms. The current prevalence for HC (1:500) is based on echocardiographic population studies in which a substantial proportion of affected subjects have not come to clinical recognition. Therefore, we sought to define the subset of patients with HC who are diagnosed in the US. A proprietary integrated claims database including medical condition International Classification of Diseases, Ninth Revision diagnostic codes for over 160 million individual patients in the US was interrogated for 2013 to identify the prevalence of clinically recognized HC. Patients with ≥1 claim for any of the HC International Classification of Diseases, Ninth Revision diagnosis codes from January to December 2013 were identified. The combined occurrence rate of HC was stratified by age and gender and multiplied by the 2013 United States population in the same age/gender categories to produce the final projected prevalence. The analysis was performed on 169,089,614 patients, of whom 59,009 unique patients were identified with ≥1 claim for HC. The projected estimated occurrence of diagnosed HC in the US in 2013 was 1:3,195 for a total of 98,958 subjects. Average age at HC diagnosis was in the fifth decade of life, with 43% of the cohort composed of women. In conclusion, leveraging a claims-based data analytic technique, about 100,000 patients are diagnosed clinically with HC in the US, an occurrence which is less than the prevalence reported in systematic population studies based on echocardiographic diagnosis. This observation supports the view that many patients with HC are undiagnosed throughout life and enhances our understanding of the burden of this genetic heart disease on the health care system. PMID:27006153

  10. Muscular (hypertrophic) subaortic stenosis (hypertrophic obstructive cardiomyopathy): the evidence for true obstruction to left ventricular outflow.

    PubMed Central

    Wigle, E. D.; Henderson, M.; Rakowski, H.; Wilansky, S.

    1986-01-01

    The clinical and haemodynamic significance of the subaortic pressure gradient in patients with muscular (hypertrophic) subaortic stenosis (hypertrophic obstructive cardiomyopathy) has long been debated. In this report we summarize the evidence which indicates that true obstruction to left ventricular outflow exists in these patients. Rapid left ventricular ejection, through an outflow tract narrowed by ventricular septal hypertrophy, results in Venturi forces causing systolic anterior motion of the anterior (or posterior) mitral leaflets. Mitral leaflet-septal contact results in obstruction to outflow and the accompanying mitral regurgitation. The time of onset of mitral leaflet-septal contact determines the magnitude of the pressure gradient and the severity of the mitral regurgitation, as well as the degree of prolongation of left ventricular ejection time and the percentage of left ventricular stroke volume that is ejected in the presence of an obstructive pressure gradient. Early and prolonged mitral leaflet-septal contact results in a large pressure gradient, significant mitral regurgitation, as well as dramatic prolongation of the ejection time and a large percentage of left ventricular stroke volume being obstructed. Late and short mitral leaflet-septal contact results in little haemodynamic perturbation. Hypertrophic cardiomyopathy patients with obstructive pressure gradients are significantly more symptomatic than those without. Thus the obstructive pressure gradients in hypertrophic cardiomyopathy are of clinical as well as haemodynamic significance. To deny the existence of obstruction to outflow in patients with muscular subaortic stenosis is to deny these patients appropriate medical and surgical therapy. PMID:3774688

  11. End-stage hypertrophic cardiomyopathy in a cat

    PubMed Central

    White, Andrew J.M.

    2015-01-01

    A 14-year-old Persian cat was referred for evaluation of the progression of hypertrophic cardiomyopathy (HCM) after an acute episode of congestive heart failure. The diagnosis of HCM had been made almost 13 years ago. Echocardiography and electrocardiography revealed end-stage hypertrophic cardiomyopathy and multifocal atrial tachycardia. The patient was discharged on medical management with a grave prognosis. PMID:25969586

  12. End-stage hypertrophic cardiomyopathy in a cat.

    PubMed

    White, Andrew J M

    2015-05-01

    A 14-year-old Persian cat was referred for evaluation of the progression of hypertrophic cardiomyopathy (HCM) after an acute episode of congestive heart failure. The diagnosis of HCM had been made almost 13 years ago. Echocardiography and electrocardiography revealed end-stage hypertrophic cardiomyopathy and multifocal atrial tachycardia. The patient was discharged on medical management with a grave prognosis. PMID:25969586

  13. Atrioventricular Sequential Pacing for Hypertrophic Cardiomyopathy During Liver Transplantation.

    PubMed

    Ramos, Juan; Pai, Sher-Lu; Perry, Dana K; Blackshear, Joseph L; Aniskevich, Stephen

    2015-10-15

    Hypertrophic cardiomyopathy is a myocardial disorder that carries an increased risk of morbidity and mortality during liver transplantation. We describe the use of atrioventricular sequential pacing, placed preoperatively, to assist with intraoperative management of a patient with severe refractory hypertrophic cardiomyopathy undergoing orthotopic piggyback liver transplantation. We discuss the pathogenesis and treatment of this infrequent but serious comorbidity. PMID:26466305

  14. Hypertrophic osteopathy associated with hepatocellular carcinoma in a dog

    PubMed Central

    Randall, Victoria D.; Souza, Carlos; Vanderhart, Daniel; Boston, Sarah

    2015-01-01

    A 9-year-old spayed female dog diagnosed with hepatocellular carcinoma and hypertrophic osteopathy was negative for additional lesions on computed tomography of the thorax and abdomen. Resection of the affected liver lobe resulted in resolution of clinical signs. This is the first case of hypertrophic osteopathy secondary to hepatocellular carcinoma. PMID:26130837

  15. Topical modalities for treatment and prevention of postsurgical hypertrophic scars.

    PubMed

    Foo, Chong Wee; Tristani-Firouzi, Payam

    2011-08-01

    There is no universally accepted treatment regimen and no evidence-based literature to guide management of hypertrophic scars. This article summarizes the existing literature regarding topical treatments such as silicone gel sheeting and ointment, onion extract, vitamin E, pressure garment therapy, massage therapy, and topical imiquimod 5% cream in the management of hypertrophic scars. PMID:21856542

  16. Blepharoptosis and hypertrophic osteoarthropathy: A case report

    PubMed Central

    Doğan, Aysun Şanal; Acaroğlu, Gölge; Dikmetas, Ozlem

    2016-01-01

    A 52-year-old male patient presented to our hospital with a history of secondary hypertrophic osteoarthropathy (HOA) associated with an abdominal neoplasia and blepharoptosis. He had finger clubbing, hyperhidrosis, and hypertrichosis. He also had a recent history of extensive abdominal surgery with a pathology report of myelolipoma. Routine blood work was unremarkable. Upper eyelid reconstruction with blepharoplasty, upper eyelid wedge resection, and brow suspension was performed to address his eyelid concerns. By this case report, we would like to attract notice that the eyelid involvement may be a part of HOA and to emphasize the importance of systemic and pathologic evaluation in failed blepharoptosis surgery. PMID:27221686

  17. Hypertrophic Cardiomyopathy in Owl Monkeys (Aotus spp.)

    PubMed Central

    Knowlen, Grant G; Weller, Richard E; Perry, Ruby L; Baer, Janet F; Gozalo, Alfonso S

    2013-01-01

    Cardiac hypertrophy is a common postmortem finding in owl monkeys. In most cases the animals do not exhibit clinical signs until the disease is advanced, making antemortem diagnosis of subclinical disease difficult and treatment unrewarding. We obtained echocardiograms, electrocardiograms, and thoracic radiographs from members of a colony of owl monkeys that previously was identified as showing a 40% incidence of gross myocardial hypertrophy at necropsy, to assess the usefulness of these modalities for antemortem diagnosis. No single modality was sufficiently sensitive and specific to detect all monkeys with cardiac hypertrophy. Electrocardiography was the least sensitive method for detecting owl monkeys with hypertrophic cardiomyopathy. Thoracic radiographs were more sensitive than was electrocardiography in this context but cannot detect animals with concentric hypertrophy without an enlarged cardiac silhouette. Echocardiography was the most sensitive method for identifying cardiac hypertrophy in owl monkeys. The most useful parameters suggestive of left ventricular hypertrophy in our owl monkeys were an increased average left ventricular wall thickness to chamber radius ratio and an increased calculated left ventricular myocardial mass. Parameters suggestive of dilative cardiomyopathy were an increased average left ventricular myocardial mass and a decreased average ratio of left ventricular free wall thickness to left ventricular chamber radius. When all 4 noninvasive diagnostic modalities (physical examination, echocardiography, electrocardiography, and thoracic radiography) were used concurrently, the probability of detecting hypertrophic cardiomyopathy in owl monkeys was increased greatly. PMID:23759531

  18. The molecular basis of hypertrophic scars.

    PubMed

    Zhu, Zhensen; Ding, Jie; Tredget, Edward E

    2016-01-01

    Hypertrophic scars (HTS) are caused by dermal injuries such as trauma and burns to the deep dermis, which are red, raised, itchy and painful. They can cause cosmetic disfigurement or contractures if craniofacial areas or mobile region of the skin are affected. Abnormal wound healing with more extracellular matrix deposition than degradation will result in HTS formation. This review will introduce the physiology of wound healing, dermal HTS formation, treatment and difference with keloids in the skin, and it also review the current advance of molecular basis of HTS including the involvement of cytokines, growth factors, and macrophages via chemokine pathway, to bring insights for future prevention and treatment of HTS. PMID:27574672

  19. Epidermolysis Bullosa with Hypertrophic Pyloric Stenosis in a Newborn

    PubMed Central

    Ben Dhaou, Mahdi; Ammar, Saloua; Louati, Hamdi; Zitouni, Hayet; Jallouli, Mohamed; Mhiri, Riadh

    2015-01-01

    Epidermolysis bullosa (EB) is an inherited blistering disorder characterized by the fragility of the skin and mucous membranes. Extracutaneous manifestations can be associated. We report a unique concomitant occurrence of EB and hypertrophic pyloric stenosis in a newborn. PMID:26500857

  20. Septal Myectomy Surgery to Treat Obstructive Hypertrophic Cardiomyopathy (HCM)

    MedlinePlus

    Septal Myectomy Surgery to Treat Obstructive Hypertrophic Cardiomyopathy (HCM) Click Here to view the BroadcastMed, Inc. Privacy Policy and Legal Notice © 2016 BroadcastMed, Inc. All rights reserved.

  1. Septal Myectomy Surgery to Treat Obstructive Hypertrophic Cardiomyopathy (HCM)

    MedlinePlus

    Septal Myectomy Surgery to Treat Obstructive Hypertrophic Cardiomyopathy (HCM) You must have Javascript enabled in your web browser. View Program Transcript Click Here to view the OR-Live, Inc. Privacy Policy ...

  2. MRI and MR tractography in bilateral hypertrophic olivary degeneration

    PubMed Central

    Sen, Debraj; Gulati, Yoginder S.; Malik, Virender; Mohimen, Aneesh; Sibi, Eranki; Reddy, Deepak Chandra

    2014-01-01

    Hypertrophic olivary degeneration is a trans-synaptic neuronal degeneration associated with hypertrophy of the inferior olivary nucleus due to a lesion in the triangle of Guillain-Mollaret. Familiarity with this entity on magnetic resonance imaging (MRI) is essential to avoid other erroneous ominous diagnoses. We present a case of bilateral hypertrophic olivary degeneration and discuss the etiopathogenesis and MRI findings in this entity. The contributory role of MR tractography in the diagnosis is also highlighted. PMID:25489133

  3. Activated keratinocytes in the epidermis of hypertrophic scars.

    PubMed Central

    Machesney, M.; Tidman, N.; Waseem, A.; Kirby, L.; Leigh, I.

    1998-01-01

    The etiology of hypertrophic scarring, a pathological end point of wound healing, is unknown. The scars most commonly occur when epithelialization has been delayed during, for example, the healing of deep dermal burn wounds. Hypertrophic scars are conventionally described as a dermal pathology in which the epidermis has only a passive role. In this study, the expression of keratin intermediate filament proteins and filaggrin has been investigated in the epidermis of hypertrophic scars and site-matched controls from the same patients. Hypertrophic scar epidermis was found to express the hyperproliferative keratins K6 and K16 in interfollicular epidermis in association with K17 and precocious expression of filaggrin. K16 mRNA was localized by in situ hybridization using a highly specific cRNA probe. In contrast to the immunohistochemical location of K16 protein, the K16 mRNA was found to be expressed in the basal cell layer of normal skin. In hypertrophic scars the mRNA distribution corroborated the abnormal K16 protein distribution. These results suggest the keratinocytes in hypertrophic scar epidermis have entered an alternative differentiation pathway and are expressing an activated phenotype. Activated keratinocytes are a feature of the early stages of wound healing producing growth factors that influence fibroblasts, endothelial cells, and the inflammatory response. We propose that cellular mechanisms in the pathogenesis of hypertrophic scarring are more complex than isolated dermal phenomena. The persistence of activated keratinocytes in hypertrophic scar epidermis implicates abnormal epidermal-mesenchymal interactions. Images Figure 1 Figure 3 PMID:9588880

  4. Morphological and immunochemical differences between keloid and hypertrophic scar.

    PubMed Central

    Ehrlich, H. P.; Desmoulière, A.; Diegelmann, R. F.; Cohen, I. K.; Compton, C. C.; Garner, W. L.; Kapanci, Y.; Gabbiani, G.

    1994-01-01

    There are two types of excessive scarring, keloid and hypertrophic scar. Contrary to hypertrophic scars, keloids do not regress with time, are difficult to revise surgically, and do not provoke scar contractures. These two lesions require different therapeutic approaches but are often confused because of an apparent lack of morphological differences. We have investigated the collagen organization and the possible presence of alpha-smooth muscle (SM) actin-expressing myofibroblasts in these conditions. Keloids contain large, thick collagen fibers composed of numerous fibrils closely packed together. In contrast hypertrophic scars exhibit modular structures in which fibroblastic cells, small vessels, and fine, randomly organized collagen fibers are present. We confirm that such nodular structures are always present in hypertrophic scar and rarely in keloid. Furthermore, only nodules of hypertrophic scars contain alpha-SM actin-expressing myofibroblasts. Electron microscopic examination supports the above-mentioned differences in collagen organization and in fibroblastic features and shows the presence of an amorphous extracellular material surrounding fibroblastic cells in keloid. The presence in hypertrophic scar myofibroblasts of alpha-SM actin, the actin isoform typical of vascular SM cells, may represent an important element in the pathogenesis of contraction. Interestingly, when placed in culture fibroblasts from hypertrophic scars and keloid express similar amounts of alpha-SM actin, suggesting that local microenvironmental factors influence in vivo the expression of this protein. Thus several morphological and immunohistochemical differences exist between hypertrophic scar and keloid that are useful for the biological and pathological characterization of the two lesions. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:8030742

  5. Stratified medicine for mental disorders.

    PubMed

    Schumann, Gunter; Binder, Elisabeth B; Holte, Arne; de Kloet, E Ronald; Oedegaard, Ketil J; Robbins, Trevor W; Walker-Tilley, Tom R; Bitter, Istvan; Brown, Verity J; Buitelaar, Jan; Ciccocioppo, Roberto; Cools, Roshan; Escera, Carles; Fleischhacker, Wolfgang; Flor, Herta; Frith, Chris D; Heinz, Andreas; Johnsen, Erik; Kirschbaum, Clemens; Klingberg, Torkel; Lesch, Klaus-Peter; Lewis, Shon; Maier, Wolfgang; Mann, Karl; Martinot, Jean-Luc; Meyer-Lindenberg, Andreas; Müller, Christian P; Müller, Walter E; Nutt, David J; Persico, Antonio; Perugi, Giulio; Pessiglione, Mathias; Preuss, Ulrich W; Roiser, Jonathan P; Rossini, Paolo M; Rybakowski, Janusz K; Sandi, Carmen; Stephan, Klaas E; Undurraga, Juan; Vieta, Eduard; van der Wee, Nic; Wykes, Til; Haro, Josep Maria; Wittchen, Hans Ulrich

    2014-01-01

    There is recognition that biomedical research into the causes of mental disorders and their treatment needs to adopt new approaches to research. Novel biomedical techniques have advanced our understanding of how the brain develops and is shaped by behaviour and environment. This has led to the advent of stratified medicine, which translates advances in basic research by targeting aetiological mechanisms underlying mental disorder. The resulting increase in diagnostic precision and targeted treatments may provide a window of opportunity to address the large public health burden, and individual suffering associated with mental disorders. While mental health and mental disorders have significant representation in the "health, demographic change and wellbeing" challenge identified in Horizon 2020, the framework programme for research and innovation of the European Commission (2014-2020), and in national funding agencies, clear advice on a potential strategy for mental health research investment is needed. The development of such a strategy is supported by the EC-funded "Roadmap for Mental Health Research" (ROAMER) which will provide recommendations for a European mental health research strategy integrating the areas of biomedicine, psychology, public health well being, research integration and structuring, and stakeholder participation. Leading experts on biomedical research on mental disorders have provided an assessment of the state of the art in core psychopathological domains, including arousal and stress regulation, affect, cognition social processes, comorbidity and pharmacotherapy. They have identified major advances and promising methods and pointed out gaps to be addressed in order to achieve the promise of a stratified medicine for mental disorders. PMID:24176673

  6. Stratified Medicine and Reimbursement Issues

    PubMed Central

    Fugel, Hans-Joerg; Nuijten, Mark; Postma, Maarten

    2012-01-01

    Stratified Medicine (SM) has the potential to target patient populations who will most benefit from a therapy while reducing unnecessary health interventions associated with side effects. The link between clinical biomarkers/diagnostics and therapies provides new opportunities for value creation to strengthen the value proposition to pricing and reimbursement (P&R) authorities. However, the introduction of SM challenges current reimbursement schemes in many EU countries and the US as different P&R policies have been adopted for drugs and diagnostics. Also, there is a lack of a consistent process for value assessment of more complex diagnostics in these markets. New, innovative approaches and more flexible P&R systems are needed to reflect the added value of diagnostic tests and to stimulate investments in new technologies. Yet, the framework for access of diagnostic-based therapies still requires further development while setting the right incentives and appropriate align stakeholders interests when realizing long-term patient benefits. This article addresses the reimbursement challenges of SM approaches in several EU countries and the US outlining some options to overcome existing reimbursement barriers for stratified medicine. PMID:23087645

  7. Sedimentation dynamics of disks in a linearly stratified fluid

    NASA Astrophysics Data System (ADS)

    Mercier, Matthieu; Pemeja, Justin; Ern, Patricia

    2014-11-01

    The settling dynamics of small objects in a stratified fluid is important to understand the fate of the biomass in lakes or oceanic environments, for industrial applications such as waste-water disposal for instance. Recent numerical and theoretical studies dedicated to freely falling (or rising) bodies in stratified environments have shown some important differences compared to the same problem in a homogeneous fluid. Experimental results are still needed for validation, especially at low and moderate values of the Reynolds number, Re = Ud / ν <= 100 , with U the instantaneous vertical velocity of the object, d its characteristic length, and ν the kinematic velocity of the fluid. We present original experimental results of freely falling disks of finite thickness in a linearly stratified fluid. Three-dimensional trajectories and the wake of the object are obtained using a pair of cameras visualizing two perpendicular planes, revealing a strong influence of the stratification on the dynamics of the object. In particular, the stratification enhances the steady drag experienced by the disks when falling broadside; and generates a change of stability for the disk orientation (from horizontal to vertical) when the Re number decreases below a threshold value.

  8. Metagenome sequencing of the prokaryotic microbiota of the hypersaline and meromictic soap lake, washington.

    PubMed

    Hawley, Erik R; Hess, Matthias

    2014-01-01

    Soap Lake is a small saline lake in central eastern Washington that is sharply stratified into two layers. In addition to being highly alkaline (~pH 10), Soap Lake also contains high concentrations of sulfide. Here, we report the community profile of the prokaryotic microbiota associated with Soap Lake surface water. PMID:24459273

  9. MR Imaging in Hypertrophic Cardiomyopathy: From Magnet to Bedside.

    PubMed

    Bogaert, Jan; Olivotto, Iacopo

    2014-11-01

    Hypertrophic cardiomyopathy ( HCM hypertrophic cardiomyopathy ), the most common genetically transmitted cardiac disorder, has been the focus of extensive research over the past 50 years. HCM hypertrophic cardiomyopathy is a multifaceted disease with highly heterogeneous genetic background, phenotypic expression, clinical presentation, and long-term outcome. Though most patients have an indolent course with a life expectancy comparable to that of the general population, early diagnosis and accurate risk profiling are essential to identify the sizeable subset at increased risk of sudden cardiac death or disease progression and heart failure-related complications, requiring aggressive management options. Imaging has a central role in the diagnosis and prognostic assessment of HCM hypertrophic cardiomyopathy patients, as well as screening of potentially affected family members. In this context, magnetic resonance (MR) imaging has recently emerged as an ideal complement to transthoracic echocardiography. Its multiparametric approach, fusing spatial, contrast, and temporal resolution, provides the clinician with detailed characterization of the HCM hypertrophic cardiomyopathy phenotype and assessment of its functional consequences including causes and site of dynamic obstruction, presence and extent of myocardial perfusion abnormalities, and fibrosis. Moreover, MR is key in differentiating HCM hypertrophic cardiomyopathy from "phenocopies"-that is, hearts with similar morphology but profoundly different etiology, such as amyloid or Anderson-Fabry disease. Long term, the incremental information provided by MR is relevant to planning of septal reduction therapies, identification of the early stages of end-stage progression, and stratification of arrhythmic risk. The aim of this review is to depict the increasingly important role of MR imaging in relation to the complexity of HCM hypertrophic cardiomyopathy , highlighting its role in clinical decision making. PMID:25340269

  10. Paraneoplastic hypertrophic osteopathy in 30 dogs

    PubMed Central

    Withers, S. S.; Johnson, E. G.; Culp, W. T. N.; Rodriguez, C. O.; Skorupski, K. A.; Rebhun, R. B.

    2016-01-01

    Paraneoplastic hypertrophic osteopathy (pHO) is known to occur in both canine and human cancer patients. While the pathology of pHO is well-described in the dog, very little information exists regarding the true clinical presentation of dogs affected with pHO. The primary objective of this study was to provide a more comprehensive clinical picture of pHO. To this end, we retrospectively identified 30 dogs and recorded data regarding presenting complaints and physical examination (PE) findings on the date of pHO diagnosis. As a secondary objective, any blood test results were also collected from the computerized records. The most common clinical signs included leg swelling, ocular discharge and/or episcleral injection, lameness, and lethargy. The most common haematological and serum biochemical abnormalities included anaemia, neutrophilia and elevated alkaline phosphatase. In addition to presenting a more detailed clinical description of pHO in the dog, these data support the previously described haematological, serum biochemical and PE abnormalities published in individual case reports. PMID:23489591

  11. Treatment of hypertrophic obstructive cardiomyopathy with verapamil.

    PubMed Central

    Kaltenbach, M; Hopf, R; Kober, G; Bussmann, W D; Keller, M; Petersen, Y

    1979-01-01

    Twenty-two patients with hypertrophic obstructive cardiomyopathy were treated with the calcium inhibitor, verapamil, which was administered in a mean oral dose of 480 mg per day. After an average of 15 months of treatment (4 to 24 months), the QRS amplitude in the electrocardiogram was significantly reduced from 4.2 to 3.8 mV. Heart volume calculated from chest x-ray films in the supine position decreased significantly from 858 to 766 ml per 1.73 m2. In 10 patients, follow-up heart catheterisation showed a decrease in left ventricular muscle mass in 7 patients and a slight increase in 3 patients. Coronary artery diameter decreased in 7 patients, increased in 1, and was unchanged in 2. The reduction in coronary artery diameter is considered to be a consequence of a reduced heart muscle mass. From all available clinical data it is concluded that verapamil treatment is superior to beta-blocker therapy. Images PMID:573129

  12. Hypertrophic pachymeningitis: significance of myeloperoxidase anti-neutrophil cytoplasmic antibody.

    PubMed

    Yokoseki, Akiko; Saji, Etsuji; Arakawa, Musashi; Kosaka, Takayuki; Hokari, Mariko; Toyoshima, Yasuko; Okamoto, Kouichirou; Takeda, Shigeki; Sanpei, Kazuhiro; Kikuchi, Hirotoshi; Hirohata, Shunsei; Akazawa, Kouhei; Kakita, Akiyoshi; Takahashi, Hitoshi; Nishizawa, Masatoyo; Kawachi, Izumi

    2014-02-01

    The aim of this study was to elucidate the characteristics, pathogenesis and treatment strategy of hypertrophic pachymeningitis that is associated with myeloperoxidase anti-neutrophil cytoplasmic antibody (ANCA). We retrospectively investigated clinical, radiological, immunological and pathological profiles of 36 patients with immune-mediated or idiopathic hypertrophic pachymeningitis, including 17 patients with myeloperoxidase-ANCA, four patients with proteinase 3-ANCA, six patients with other immune-mediated disorders, and nine patients with 'idiopathic' variety. Myeloperoxidase-ANCA-positive hypertrophic pachymeningitis was characterized by: (i) an elderly female predominance; (ii) 82% of patients diagnosed with granulomatosis with polyangiitis (previously known as Wegener's granulomatosis) according to Watts' algorithm; (iii) a high frequency of patients with lesions limited to the dura mater and upper airways, developing headaches, chronic sinusitis, otitis media or mastoiditis; (iv) a low frequency of patients with the 'classical or generalized form' of granulomatosis with polyangiitis involving the entire upper and lower airways and kidney, or progressing to generalized disease, in contrast to proteinase 3-ANCA-positive hypertrophic pachymeningitis; (v) less severe neurological damage according to the modified Rankin Scale and low disease activity according to the Birmingham Vasculitis Activity Score compared with proteinase 3-ANCA-positive hypertrophic pachymeningitis; (vi) increased levels of CXCL10, CXCL8 and interleukin 6 in cerebrospinal fluids, and increased numbers of T cells, neutrophils, eosinophils, plasma cells and monocytes/macrophages in autopsied or biopsied dura mater with pachymeningitis, suggesting TH1-predominant granulomatous lesions in hypertrophic pachymeningitis, as previously reported in pulmonary or renal lesions of granulomatosis with polyangiitis; and (vii) greater efficacy of combination therapy with prednisolone and

  13. Medicinal Plants for the Treatment of Hypertrophic Scars

    PubMed Central

    Ye, Qi; Wang, Su-Juan; Chen, Jian-Yu; Xin, Hai-Liang; Zhang, Hong

    2015-01-01

    Hypertrophic scar is a complication of wound healing and has a high recurrence rate which can lead to significant abnormity in aesthetics and functions. To date, no ideal treatment method has been established. Meanwhile, the underlying mechanism of hypertrophic scarring has not been clearly defined. Although a large amount of scientific research has been reported on the use of medicinal plants as a natural source of treatment for hypertrophic scarring, it is currently scattered across a wide range of publications. Therefore, a systematic summary and knowledge for future prospects are necessary to facilitate further medicinal plant research for their potential use as antihypertrophic scar agents. A bibliographic investigation was accomplished by focusing on medicinal plants which have been scientifically tested in vitro and/or in vivo and proved as potential agents for the treatment of hypertrophic scars. Although the chemical components and mechanisms of action of medicinal plants with antihypertrophic scarring potential have been investigated, many others remain unknown. More investigations and clinical trials are necessary to make use of these medical plants reasonably and phytotherapy is a promising therapeutic approach against hypertrophic scars. PMID:25861351

  14. PHOTOSPHERIC EMISSION FROM STRATIFIED JETS

    SciTech Connect

    Ito, Hirotaka; Nagataki, Shigehiro; Ono, Masaomi; Lee, Shiu-Hang; Mao, Jirong; Yamada, Shoichi; Pe'er, Asaf; Mizuta, Akira; Harikae, Seiji

    2013-11-01

    We explore photospheric emissions from stratified two-component jets, wherein a highly relativistic spine outflow is surrounded by a wider and less relativistic sheath outflow. Thermal photons are injected in regions of high optical depth and propagated until the photons escape at the photosphere. Because of the presence of shear in velocity (Lorentz factor) at the boundary of the spine and sheath region, a fraction of the injected photons are accelerated using a Fermi-like acceleration mechanism such that a high-energy power-law tail is formed in the resultant spectrum. We show, in particular, that if a velocity shear with a considerable variance in the bulk Lorentz factor is present, the high-energy part of observed gamma-ray bursts (GRBs) photon spectrum can be explained by this photon acceleration mechanism. We also show that the accelerated photons might also account for the origin of the extra-hard power-law component above the bump of the thermal-like peak seen in some peculiar bursts (e.g., GRB 090510, 090902B, 090926A). We demonstrate that time-integrated spectra can also reproduce the low-energy spectrum of GRBs consistently using a multi-temperature effect when time evolution of the outflow is considered. Last, we show that the empirical E{sub p}-L{sub p} relation can be explained by differences in the outflow properties of individual sources.

  15. Photospheric Emission from Stratified Jets

    NASA Astrophysics Data System (ADS)

    Ito, Hirotaka; Nagataki, Shigehiro; Ono, Masaomi; Lee, Shiu-Hang; Mao, Jirong; Yamada, Shoichi; Pe'er, Asaf; Mizuta, Akira; Harikae, Seiji

    2013-11-01

    We explore photospheric emissions from stratified two-component jets, wherein a highly relativistic spine outflow is surrounded by a wider and less relativistic sheath outflow. Thermal photons are injected in regions of high optical depth and propagated until the photons escape at the photosphere. Because of the presence of shear in velocity (Lorentz factor) at the boundary of the spine and sheath region, a fraction of the injected photons are accelerated using a Fermi-like acceleration mechanism such that a high-energy power-law tail is formed in the resultant spectrum. We show, in particular, that if a velocity shear with a considerable variance in the bulk Lorentz factor is present, the high-energy part of observed gamma-ray bursts (GRBs) photon spectrum can be explained by this photon acceleration mechanism. We also show that the accelerated photons might also account for the origin of the extra-hard power-law component above the bump of the thermal-like peak seen in some peculiar bursts (e.g., GRB 090510, 090902B, 090926A). We demonstrate that time-integrated spectra can also reproduce the low-energy spectrum of GRBs consistently using a multi-temperature effect when time evolution of the outflow is considered. Last, we show that the empirical E p-L p relation can be explained by differences in the outflow properties of individual sources.

  16. Familial spontaneous complete heart block in hypertrophic cardiomyopathy.

    PubMed Central

    Louie, E K; Maron, B J

    1986-01-01

    Two siblings with hypertrophic cardiomyopathy developed spontaneous complete heart block requiring permanent pacemaker implantation at similar ages (29 and 33 years). The clinical, morphological, and haemodynamic expressions of hypertrophic cardiomyopathy differed considerably in these two patients. The sister had severe functional limitation due to dyspnoea, pronounced and diffuse left ventricular hypertrophy (maximum ventricular septal thickness of 41 mm), and left ventricular outflow obstruction (peak subaortic gradient of 75 mm Hg under basal conditions). In contrast the brother was symptom free, had only modest left ventricular hypertrophy which was confined to the anterior ventricular septum (maximal thickness of 16 mm), and had no echocardiographic evidence of subaortic obstruction. These dissimilar findings in siblings with hypertrophic cardiomyopathy suggest that the predisposition to develop complete heart block was probably genetically transmitted, although it was unrelated to the phenotypic and clinical expression of the disease. Images Fig. 2 Fig. 3 PMID:3707787

  17. Phonoechocardiography and intracardiac phonocardiography in hypertrophic cardiomyopathy.

    PubMed Central

    Shaver, J. A.; Alvares, R. F.; Reddy, P. S.; Salerni, R.

    1986-01-01

    The salient phonoechocardiographic features of patients having hypertrophic cardiomyopathy (HCM) with or without left ventricular outflow tract (LVOT) gradients are reviewed. Intracardiac sound and pressure recordings from high fidelity catheter-tipped micromanometers have documented that the precordial murmur is the summation of both the systolic ejection murmur (SEM) arising from the LVOT, as well as the mitral regurgitant murmur recorded from the left atrium. The intensity of the precordial murmur varies directly with the LVOT gradient, which in turn is determined primarily by the contractility and loading conditions of the left ventricle. Reversed splitting of the second heart sound (S2) with paradoxical respiratory movement is a common finding in HCM, and when present, almost always denotes a significant LVOT gradient. It is due to marked lengthening of the left ventricular ejection time secondary to prolongation of the contraction and relaxation phases of left ventricular systole. The presence of a fourth heart sound (S4) is the rule in HCM when normal sinus rhythm is present, and is a reflection of a forceful left atrial contraction into a hypertrophied noncompliant left ventricle. A third heart sound (S3) is also common in HCM, and often the initial vibrations occur before the 0 point of the apexcardiogram (ACG) and continue giving the auscultatory impression of a diastolic rumble. When associated with a loud S1, which is frequently present, the clinical presentation may mimic mitral stenosis. This is particularly true when the patient has chronic atrial fibrillation. Careful attention to evidence of marked left ventricular hypertrophy as well as the typical echocardiographic findings of HCM preclude this diagnosis. In conclusion, phonoechocardiography is a simple non-invasive technique which almost always makes the definitive diagnosis of HCM. PMID:3774689

  18. Lake Life.

    ERIC Educational Resources Information Center

    Ohrn, Deborah Gore, Ed.

    1993-01-01

    This quarterly publication of the State Historical Society of Iowa features articles and activities for elementary school students. This summer issue focuses on the topic of lake life. The issue includes the following features: (1) "Where the Lakes Are Map"; (2) "Letter from the Lake"; (3) "Lake People"; (4) "Spirit Lake"; (5) "Lake Manawa"; (6)…

  19. Familial idiopathic hypertrophic osteoarthropathy and cranial suture defects in children

    SciTech Connect

    Reginato, A.J.; Schiapachasse, V.; Guerrero, R.

    1982-05-01

    Three children with idiopathic hypertrophic osteoarthropathy and cranial suture defects are reported. The syndrome was recognized after birth and in the two oldest siblings, the cranial defects and subperiosteal bone formation resolved almost completely by age 4 and 6 years. The joint swelling and clubbing persisted and mild bone reabsorption of the distal phalanges became apparent at an older age. Two siblings and both parents had normal bone X-rays and no clubbing. This study confirms the association of cranial sutural defects and familial idopathic hypertrophic osteoarthropathy.

  20. [Left ventricular hypertrophy in the cat - "when hypertrophic cardiomyopathy is not hypertrophic cardiomyopathy"].

    PubMed

    Glaus, T; Wess, G

    2010-07-01

    According to WHO classification hypertrophic cardiomyopathy (HCM) is a primary genetic cardiomyopathy. Echocardiographically HCM is characterized by symmetric, asymmetric or focal left ventricular hypertrophy (LVH) without recognizable underlying physical cause. However, echocardiographically HCM in cats may not be distinguishable from other causes of a thick appearing left ventricle. Hypovolemia can look like a hypertrophied ventricle but is basically only pseudohypertrophic. Well recognized and logical physical causes of LVH include systemic hypertension and outflow obstruction. LVH similar to HCM may also be found in feline hyperthyroidism. The context of the disease helps to differentiate these physical / physiological causes of LVH. Difficult to distinguish from HCM, particularly when based on a snapshot of a single echocardiographic exam, are myocarditis and . Only the clinical and echocardiographic course allow a reasonably confident etiological diagnosis and the differentiation between HCM and secondary LVH. PMID:20582898

  1. Hypertrophic osteoarthropathy presenting as unilateral cellulitis with successful treatment using pamidronate disodium.

    PubMed

    Bernardo, Sebastian G; Emer, Jason J; Burnett, Mark E; Gordon, Marsha

    2012-09-01

    Hypertrophic pulmonary osteoarthropathy is a paraneoplastic syndrome seen in patients with lung cancer. This condition is characterized by the presence of digital clubbing, periosteal thickening, synovial thickening, and severe pain of the affected joints. Other syndromes exhibiting clubbing may or may not have underlying diseases causing their manifestation. An example is primary hypertrophic osteoarthropathy, or pachydermoperiostosis. While clubbing makes up part of the clinical picture in both hypertrophic pulmonary osteoarthropathy and hypertrophic osteoarthropathy, the latter has no underlying disease associations. Rather, primary hypertrophic osteoarthropathy is familial, idiopathic, and has a chronic course often beginning during puberty in males. Secondary hypertrophic osteoarthropathy is an acquired form of clubbing that is classically associated with lung disease. However, it has also been associated with diseases of the heart, liver, and intestines. In the setting of pulmonary malignancy, secondary hypertrophic osteoarthropathy is known as hypertrophic pulmonary osteoarthropathy. Hypertrophic pulmonary osteoarthropathy has a distinct constellation of clinical findings that includes intractable pain often refractory to treatments other than resolution of the underlying disease process. The authors herein report a case of hypertrophic pulmonary osteoarthropathy masquerading as recurrent lower extremity cellulitis with chronic hand and foot pain in the setting of pulmonary malignancy that responded dramatically to intravenous pamidronate disodium (a bisphosphonate). Given the rarity of hypertrophic osteoarthropathy associated with lung cancer and the difficulty with pain management in such circumstances, the authors present the following case in which pain was mitigated by treatment with bisphosphonate therapy. PMID:23050033

  2. Photoinduced spinodal decomposition in stratifying solutions

    NASA Astrophysics Data System (ADS)

    Bunkin, F. V.; Podgaetskii, V. I.; Semin, V. N.

    1988-01-01

    The effect of photoinduced spinodal decomposition in stratifying solutions is examined with particular reference to experimental results obtained for an aqueous solution of butyl Cellosolve of critical concentration (30.14 percent by mass). At the late stages of spinodal decomposition, the coalescence of similar microheterophase inhomogeneities leads to the formation of small-scale (up to 5 microns) grains of each of the phases, which are then grouped into larger-scale (up to 100 microns) segregations. Such multilevel self-organization of the stratifying phases leads to the formation of a granular-cellular structure. This effect can be used for the quick interruption of chemical reactions in a stratifying solution.

  3. Waves in Turbulent Stably Stratified Shear Flow

    NASA Technical Reports Server (NTRS)

    Jacobitz, F. G.; Rogers, M. M.; Ferziger, J. H.; Parks, John W. (Technical Monitor)

    2002-01-01

    Two approaches for the identification of internal gravity waves in sheared and unsheared homogeneous stratified turbulence are investigated. First, the phase angle between the vertical velocity and density fluctuations is considered. It was found, however, that a continuous distribution of the phase angle is present in weakly and strongly stratified flow. Second, a projection onto the solution of the linearized inviscid equations of motion of unsheared stratified flow is investigated. It was found that a solution of the fully nonlinear viscous Navier-Stokes equations can be represented by the linearized inviscid solution. The projection yields a decomposition into vertical wave modes and horizontal vortical modes.

  4. Sediment Ammonia-Oxidizing Microorganisms in Two Plateau Freshwater Lakes at Different Trophic States.

    PubMed

    Yang, Yuyin; Zhang, Jingxu; Zhao, Qun; Zhou, Qiheng; Li, Ningning; Wang, Yilin; Xie, Shuguang; Liu, Yong

    2016-02-01

    Both ammonia-oxidizing archaea (AOA) and bacteria (AOB) can contribute to ammonia biotransformation in freshwater lake ecosystems. However, the factors shaping the distribution of sediment AOA and AOB in plateau freshwater lake remains unclear. The present study investigated sediment AOA and AOB communities in two freshwater lakes (hypertrophic Dianchi Lake and mesotrophic Erhai Lake) on the Yunnan Plateau (China). A remarkable difference in the abundance, diversity, and composition of sediment AOA and AOB communities was observed between Dianchi Lake and Erhai Lake. AOB usually outnumbered AOA in Dianchi Lake, but AOA showed the dominance in Erhai Lake. Organic matter (OM), total nitrogen (TN), and total phosphorus (TP) might be the key determinants of AOB abundance, while AOA abundance was likely influenced by the ration of OM to TN (C/N). AOA or AOB community structure was found to be relatively similar in the same lake. TN and TP might play important roles in shaping sediment AOA and AOB compositions in Dianchi Lake and Erhai Lake. Moreover, Nitrososphaera-like AOA were detected in Dianchi Lake. Nitrosospira- and Nitrosomonas-like AOB were dominant in Dianchi Lake and Erhai Lake, respectively. Sediment AOA and AOB communities in Dianchi Lake and Erhai Lake were generally regulated by trophic state. PMID:26111964

  5. How stratified is mantle convection?

    NASA Astrophysics Data System (ADS)

    Puster, Peter; Jordan, Thomas H.

    1997-04-01

    due to slabs alone. A stratification index, Sƒ≲0.2, is sufficient to exclude many stratified convection models still under active consideration, including most forms of chemical layering between the upper and lower mantle, as well as the more extreme versions of avalanching convection governed by a strong endothermic phase change.

  6. Red blood cell sodium heteroexchange in familial primary hypertrophic cardiomyopathy.

    PubMed

    Semplicini, A; Mozzato, M G; Bongiovi, S; Marzola, M; Macor, F; Ceolotto, G; Serena, L; Pessina, A C

    1994-03-01

    The hallmark of primary hypertrophic cardiomyopathy is an inappropriate myocardial hypertrophy, linked to myofibril disarray of the left ventricle. Its variable clinical expression may be due to genetic heterogeneity and variable penetrance. Since we have recently shown that abnormalities of cation transport in the erythrocytes are associated with cardiac hypertrophy in essential hypertensives and insulin-dependent diabetics, we have investigated the relationship between cardiac anatomy and function and red cell Li+/Na+ and Na+/H+ exchange in 33 relatives of a patient who died of cardiac failure and was found to have a primary hypertrophic cardiomyopathy at autopsy. According to echocardiographic examination, 11 members of the family also had a hypertrophic cardiomyopathy, with a family distribution compatible with autosomal dominant genetic transmission and variable penetrance. Red cell Li+/Na+ and Na+/H+ exchange were not significantly different in the affected members as compared to the unaffected, but in the former, after correction for potentially confounding variables, interventricular septum thickness was positively correlated to Na+/H+ exchange and diastolic function (Area E/Area A and Vmax E/Vmax A) negatively correlated to Li+/Na+ exchange. Since a generalized overactivity of the cell membrane Na+/H+ exchange, reflected by increased Na+/H+ and Li+/Na+ exchanges in the red cells, could favour cellular growth and diastolic dysfunction, our data suggest that abnormalities of cell membrane cation transport could play a role in the phenotypic expression of hypertrophic cardiomyopathy. PMID:8013504

  7. Hypertrophic Cardiomyopathy: Practical Steps for Preventing Sudden Death.

    ERIC Educational Resources Information Center

    Maron, Barry J.

    2002-01-01

    Hypertrophic cardiomyopathy (HCM) is a rare cause of death among athletes, with deaths occurring in young, apparently healthy people. Differentiating HCM from conditioning hypertrophy is challenging. Routine detection involves family history, physical examination, electrocardiography, and echocardiography. Keys to differential diagnosis include…

  8. Hypertrophic cardiomyopathy in infants: clinical features and natural history

    SciTech Connect

    Maron, B.J.; Tajik, A.J.; Ruttenberg, H.D.; Graham, T.P.; Atwood, G.F.; Victorica, B.E.; Lie, J.T.; Roberts, W.C.

    1982-01-01

    The clinical and morphologic features of hypertrophic cardiomyopathy in 20 patients recognized as having cardiac disease in the first year of life are described. Fourteen of these 20 infants were initially suspected of having heart disease solely because a heart murmur was identified. However, the infants showed a variety of clinical findings, including signs of marked congestive heart failure (in the presence of nondilated ventricular cavities and normal or increased left ventricular contractility) and substantial cardiac enlargement on chest radiograph. Other findings were markedly different from those usually present in older children and adults with hypertrophic cardiomyopathy (e.g., right ventricular hypertrophy on the ECG and cyanosis). Consequently, in 14 infants, the initial clinical diagnosis was congenital cardiac malformation other than hypertrophic cardiomyopathy. The clinical course was variable in these patients, but the onset of marked congestive heart failure in the first year of life appeared to be an unfavorable prognostic sign; nine of the 11 infants with congestive heart failure died within the first year of life. In infants with hypertrophic cardiomyopathy, unlike older children and adults with this condition, sudden death was less common (two patients) than death due to progressive congestive heart failure.

  9. Difficulty of diagnosing infected hypertrophic pseudarthrosis by radionuclide imaging

    SciTech Connect

    Hadjipavlou, A.; Lisbona, R.; Rosenthall, L.

    1983-02-01

    Hypertrophic pseudarthrosis was studied with /sup 99m/Tc MDP and /sup 67/Ga citrate in 11 patients. Two of the 11 pseudarthroses were complicated by infection. A high concentration of both radiopharmaceuticals was obtained at all 11 sites and their distribution patterns were identical. It was therefore impossible to distinguish the infected from the noninfected pseudarthroses by using /sup 67/Ga.

  10. Interaction of two spheres settling in a linearly stratified fluid

    NASA Astrophysics Data System (ADS)

    Mercier, Matthieu; Toupoint, Clement; Ern, Patricia

    2015-11-01

    The settling dynamics of small objects in stratified fluids is important to understand the fate of the biomass in lakes or oceanic environments, for industrial applications such as waste-water disposal. More specifically, the interaction of two settling bodies is a fundamental problem recently studied numerically for spheres. Experimental results are needed for validation, especially at low and moderate values of the Reynolds number, for different values of the Froude number, the other parameter of interest. We present experimental results on the interaction of two spheres settling in a linearly stratified fluid. The settling dynamics is investigated by tracking their trajectories in three dimensions, using a pair of cameras imaging two perpendicular planes. Two typical cases are observed, the horizontal repulsion of particles initially aligned horizontally, and the Drafting-Kissing-Tumbling of spheres initially aligned vertically. The influence of the initial positions of the spheres, the Reynolds and Froude numbers, is investigated to quantify these effects and their robustness, in comparison to the dynamics in an homogeneous fluid.

  11. UPSTREAM MOTIONS IN STRATIFIED FLOW (JOURNAL VERSION)

    EPA Science Inventory

    In the paper experimental measurements of the time-dependent velocity and density perturbations upstream of obstacles in linearly stratified flow are presented. Attention is concentrated on obstacles which generate turbulent separated wakes at Froude numbers, based on velocity an...

  12. Future volcanic lake research: revealing secrets from poorly studied lakes

    NASA Astrophysics Data System (ADS)

    Rouwet, D.; Tassi, F.; Mora-Amador, R. A.

    2012-04-01

    Volcanic lake research boosted after the 1986 Lake Nyos lethal gas burst, a limnic rather than volcanic event. This led to the formation of the IAVCEI-Commission on Volcanic Lakes, which grew out into a multi-disciplinary scientific community since the 1990's. At Lake Nyos, a degassing pipe is functional since 2001, and two additional pipes were added in 2011, aimed to prevent further limnic eruption events. There are between 150 and 200 volcanic lakes on Earth. Some acidic crater lakes topping active magmatic-hydrothermal systems are monitored continuously or discontinuously. Such detailed studies have shown their usefulness in volcanic surveillance (e.g. Ruapehu, Yugama-Kusatsu-Shiran, Poás). Others are "Nyos-type" lakes, with possible gas accumulation in bottom waters and thus potentially hazardous. "Nyos-type" lakes tend to remain stably stratified in tropical and sub-tropical climates (meromictic), leading to long-term gas build-up and thus higher potential risk. In temperate climates, such lakes tend to turn over in winter (monomictic), and thus liberating its gas charge yearly. We line out research strategies for the different types of lakes. We believe a complementary, multi-disciplinary approach (geochemistry, geophysics, limnology, biology, statistics, etc.) will lead to new insights and ideas, which can be the base for future following-up and monitoring. After 25 years of pioneering studies on rather few lakes, the scientific community should be challenged to study the many poorly studied volcanic lakes, in order to better constrain the related hazard, based on probabilistic approaches.

  13. THE WESTERN LAKE SUPERIOR COMPARATIVE WATERSHED FRAMEWORK: A FIELD TEST OF GEOGRAPHICALLY-DEPENDENT VS. THRESHOLD-BASED GEOGRAPHICALLY-INDEPENDENT CLASSIFICATION

    EPA Science Inventory

    Stratified random selection of watersheds allowed us to compare geographically-independent classification schemes based on watershed storage (wetland + lake area/watershed area) and forest fragmentation with a geographically-based classification scheme within the Northern Lakes a...

  14. BEHAVIOR OF ARSENIC AND OTHER REDOX-SENSITIVE ELEMENTS IN CROWLEY LAKE, CA: A RESERVOIR IN THE LOS ANGELES AQUEDUCT SYSTEM. (R826202)

    EPA Science Inventory

    Elevated arsenic concentrations in Crowley Lake derive from upstream geothermal inputs. We examined the water column of Crowley Lake under stratified and unstratified conditions, seeking evidence for algal uptake and transformation of arsenic and its deposition to and release fro...

  15. Magnetized stratified rotating shear waves

    NASA Astrophysics Data System (ADS)

    Salhi, A.; Lehner, T.; Godeferd, F.; Cambon, C.

    2012-02-01

    solution at infinite vertical wavelength (k3=0): There is an oscillatory behavior for τ>1+|K2/k1|, where τ=St is a dimensionless time and K2 is the radial component of the wave vector at τ=0. The model is suitable to describe instabilities leading to turbulence by the bypass mechanism that can be relevant for the analysis of magnetized stratified Keplerian disks with a purely azimuthal field. For initial isotropic conditions, the time evolution of the spectral density of total energy (kinetic + magnetic + potential) is considered. At k3=0, the vertical motion is purely oscillatory, and the sum of the vertical (kinetic + magnetic) energy plus the potential energy does not evolve with time and remains equal to its initial value. The horizontal motion can induce a rapid transient growth provided K2/k1≫1. This rapid growth is due to the aperiodic velocity vortex mode that behaves like Kh/kh where kh(τ)=[k12+(K2-k1τ)2]1/2 and Kh=kh(0). After the leading phase (τ>K2/k1≫1), the horizontal magnetic energy and the horizontal kinetic energy exhibit a similar (oscillatory) behavior yielding a high level of total energy. The contribution to energies coming from the modes k1=0 and k3=0 is addressed by investigating the one-dimensional spectra for an initial Gaussian dense spectrum. For a magnetized Keplerian disk with a purely vertical field, it is found that an important contribution to magnetic and kinetic energies comes from the region near k1=0. The limit at k1=0 of the streamwise one-dimensional spectra of energies, or equivalently, the streamwise two-dimensional (2D) energy, is then computed. The comparison of the ratios of these 2D quantities with their three-dimensional counterparts provided by previous direct numerical simulations shows a quantitative agreement.

  16. Magnetized stratified rotating shear waves.

    PubMed

    Salhi, A; Lehner, T; Godeferd, F; Cambon, C

    2012-02-01

    stability of the solution at infinite vertical wavelength (k(3) = 0): There is an oscillatory behavior for τ > 1+|K(2)/k(1)|, where τ = St is a dimensionless time and K(2) is the radial component of the wave vector at τ = 0. The model is suitable to describe instabilities leading to turbulence by the bypass mechanism that can be relevant for the analysis of magnetized stratified Keplerian disks with a purely azimuthal field. For initial isotropic conditions, the time evolution of the spectral density of total energy (kinetic + magnetic + potential) is considered. At k(3) = 0, the vertical motion is purely oscillatory, and the sum of the vertical (kinetic + magnetic) energy plus the potential energy does not evolve with time and remains equal to its initial value. The horizontal motion can induce a rapid transient growth provided K(2)/k(1)>1. This rapid growth is due to the aperiodic velocity vortex mode that behaves like K(h)/k(h) where k(h)(τ)=[k(1)(2) + (K(2) - k(1)τ)(2)](1/2) and K(h) =k(h)(0). After the leading phase (τ > K(2)/k(1)>1), the horizontal magnetic energy and the horizontal kinetic energy exhibit a similar (oscillatory) behavior yielding a high level of total energy. The contribution to energies coming from the modes k(1) = 0 and k(3) = 0 is addressed by investigating the one-dimensional spectra for an initial Gaussian dense spectrum. For a magnetized Keplerian disk with a purely vertical field, it is found that an important contribution to magnetic and kinetic energies comes from the region near k(1) = 0. The limit at k(1) = 0 of the streamwise one-dimensional spectra of energies, or equivalently, the streamwise two-dimensional (2D) energy, is then computed. The comparison of the ratios of these 2D quantities with their three-dimensional counterparts provided by previous direct numerical simulations shows a quantitative agreement. PMID:22463311

  17. Analysis of hypertrophic and normal scar gene expression with cDNA microarrays.

    PubMed

    Tsou, R; Cole, J K; Nathens, A B; Isik, F F; Heimbach, D M; Engrav, L H; Gibran, N S

    2000-01-01

    Hypertrophic scar is one form of abnormal wound healing. Previous studies have suggested that hypertrophic scar formation results from altered gene expression of extracellular matrix molecules. A broadscale evaluation of gene expression in hypertrophic scars has not been reported. To better understand abnormalities in hypertrophic scar gene expression, we compared messenger RNA expression in hypertrophic scars, normal scars, and uninjured skin with the use of complementary (c)DNA microarrays. Total RNA was extracted from freshly excised human hypertrophic scars, normal scars, or uninjured skin and reverse transcribed into cDNA with the incorporation of [33P] deoxycytidine triphosphate. The resulting radioactive cDNA probes were hybridized onto cDNA microarrays of 4000 genes. Hybridization signals were normalized and analyzed. In the comparison of tissue samples, mean intensities were calculated for each gene within each group (hypertrophic scars, normal scars, and uninjured skin). Ratios of the mean intensities of hypertrophic scars to normal scars, hypertrophic scars to uninjured skin, and normal scars to uninjured skin were generated. A ratio that was greater than 1 indicated upregulation of any particular gene and a ratio that was less than 1 indicated downregulation of any particular gene. Our data indicated that 142 genes were overexpressed and 50 genes were underexpressed in normal scars compared with uninjured skin, 107 genes were overexpressed and 71 were underexpressed in hypertrophic scars compared with uninjured skin, and 44 genes were overexpressed and 124 were underexpressed in hypertrophic scars compared with normal scars. Our analysis of collagen, growth factor, and metalloproteinase gene expression confirmed that our molecular data were consistent with published biochemical and clinical observations of normal scars and hypertrophic scars. cDNA microarray analysis provides a powerful tool for the investigation of differential gene expression in

  18. Hypertrophic Cardiomyopathy Registry (HCMR): The rationale and design of an international, observational study of hypertrophic cardiomyopathy

    PubMed Central

    Kramer, Christopher M.; Appelbaum, Evan; Desai, Milind Y.; Desvigne-Nickens, Patrice; DiMarco, John P.; Friedrich, Matthias G.; Geller, Nancy; Heckler, Sarahfaye; Ho, Carolyn Y.; Jerosch-Herold, Michael; Ivey, Elizabeth A.; Keleti, Julianna; Kim, Dong-Yun; Kolm, Paul; Kwong, Raymond Y.; Maron, Martin S.; Schulz-Menger, Jeanette; Piechnik, Stefan; Watkins, Hugh; Weintraub, William S.; Wu, Pan; Neubauer, Stefan

    2015-01-01

    Hypertrophic cardiomyopathy (HCM) is the most common monogenic heart disease with a frequency as high as 1 in 200. In many cases, HCM is caused by mutations in genes encoding the different components of the sarcomere apparatus. HCM is characterized by unexplained left ventricular hypertrophy (LVH), myofibrillar disarray, and myocardial fibrosis. The phenotypic expression is quite variable. While the majority of patients with HCM are asymptomatic, serious consequences are experienced in a subset of affected individuals who present initially with sudden cardiac death (SCD) or progress to refractory heart failure (HF). The HCMR study is a National Heart Lung and Blood Institute (NHLBI)-sponsored 2750 patient, 41 site, international registry and natural history study designed to address limitations in extant evidence to improve prognostication in HCM (NCT01915615). In addition to collection of standard demographic, clinical, and echocardiographic variables, patients will undergo state-of-the-art cardiac magnetic resonance (CMR) for assessment of left ventricular (LV) mass and volumes as well as replacement scarring and interstitial fibrosis. In addition, genetic and biomarker analysis will be performed. HCMR has the potential to change the paradigm of risk stratification in HCM, using novel markers to identify those at higher risk. PMID:26299218

  19. Effects of Noscarna™ on hypertrophic scarring in the rabbit ear model: histopathological aspects.

    PubMed

    Lee, Dong Won; Ku, Sae Kwang; Cho, Hyuk Jun; Kim, Jeong Hwan; Hiep, Tran Tuan; Han, Sang Duk; Kim, Bo Gyun; Kang, Min Kyung; Do, Eui Seon; Jun, Joon Ho; Jang, Sun Woo; Son, Mi-Won; Sohn, Young Taek; Choi, Han-Gon; Yong, Chul Soon; Kim, Jong Oh

    2012-11-01

    In this study, we evaluated the effects of silicone-based gel on the healing of hypertrophic scars in the rabbit ear model. After 4-week application of silicone-based gel containing allantoin, dexpanthenol and heparin (Noscarna™) to scars in a rabbit ear model of hypertrophic scarring, significant improvements in hypertrophic scar healing and a great loss of skin pigment were observed compared to the non-treated control, base or silicone control-treated scars. Furthermore, histological analysis of Noscarna™-treated scars revealed a significant reduction in scar elevation index (SEI), anterior skin and epithelial thicknesses, inflammatory cells, vessels, collagen disorganization and fibroblasts compared to all control hypertrophic scars. Furthermore, Noscarna™ showed more favorable effects on hypertrophic scars than a commercial product, Contractubex®. Therefore, these results clearly demonstrated that the newly developed silicone-based gel, Noscarna™, could be a promising formulation as an effective therapeutic agent for hypertrophic scars. PMID:23212642

  20. Primary antiphospholipid syndrome, hypertrophic non-obstructive cardiomyopathy and hypotelorism.

    PubMed

    Kellermair, Joerg; Kammler, Juergen; Laubichler, Peter; Steinwender, Clemens

    2016-01-01

    Antiphospholipid syndrome (APS) is an autoimmune disorder associated with arterial/venous thrombosis. Cardiac manifestations of APS include valve stenosis/insufficiency, coronary artery disease and myocardial dysfunction presenting as dilated cardiomyopathy. In the following report, we present the case of a man with primary APS, hypertrophic non-obstructive cardiomyopathy and hypotelorism-a combination that has not yet been reported in the literature. PMID:27048398

  1. Hypertrophic osteopathy associated with a renal adenoma in a cat.

    PubMed

    Johnson, Robert L; Lenz, Stephen D

    2011-01-01

    Hypertrophic osteopathy is a hyperostotic syndrome of the appendicular skeleton that is most commonly associated with intrathoracic neoplasia or inflammation. The condition is rarely associated with intra-abdominal lesions. The majority of cases have occurred in dogs and human beings, with fewer cases reported in cats, horses, and other species. A 15-year-old male neutered Domestic Shorthair cat presented for swollen limbs and difficulty in ambulation. Radiographs and gross postmortem revealed severe periosteal hyperostosis of the diaphysis and metaphysis of all 4 limbs, including the humerus, radius, ulna, carpi, metacarpi, femur, tibia, tarsi, metatarsi, and phalanges. The axial skeleton was spared. Hyperostotic lesions were characterized microscopically by lamellar bony trabeculae separated by adipocytes and scant hematopoietic tissue. In several areas, fibrovascular connective tissue, woven bone, and islands of cartilage were also present. A 2.5 cm × 2.5 cm perirenal neoplasm compressed the left kidney and adrenal gland. This mass consisted of well-differentiated tubules of cuboidal epithelial cells and was most consistent with a renal tubular adenoma, because mitotic figures were rare, and no distant metastases were found. Thoracic pathology was absent. Hyperostosis was consistent with hypertrophic osteopathy secondary to the renal adenoma. The pathogenesis of hypertrophic osteopathy is uncertain, but predominant theories point to increased peripheral circulation and angiogenesis as a key initiating event. Recent literature highlights the potential role of vascular endothelial growth factor and platelet-derived growth factor in the human condition. The mechanism by which this renal adenoma caused hypertrophic osteopathy is unknown. PMID:21217054

  2. Hypertrophic neuropathy in Noonan syndrome with multiple lentigines.

    PubMed

    Maridet, Claire; Sole, Guilhem; Morice-Picard, Fanny; Taieb, Alain

    2016-06-01

    RASopathies comprise several genetic syndromes with mainly cardio-facial-cutaneous manifestations. We report a patient with Noonan syndrome with multiple lentigines (NSML) due to a PTPN11 (p.Thr468Met) mutation associated with hypertrophic neuropathy of lumbar plexus in an adult woman, initially referred for neuropathic pain. Differential diagnosis of neurofibromatosis type 1 (NF1) and other RASopathies is difficult without molecular testing. © 2016 Wiley Periodicals, Inc. PMID:26952712

  3. [The sonographic diagnosis of hypertrophic stenosis of the pylorus].

    PubMed

    Rodríguez, R I; Briceño de Rodríguez, J A; Urrutia, M

    1993-09-01

    The clinical records of 18 children were studied, between 15 and 60 days old. They were hospitalized due to vomiting and diagnosis of suspected pyloric hypertrophic stenosis (PHS). The sonography confirmed the diagnosis in 8 children, by the thickening of the muscular layer and enlargement of the pyloric canal. The surgery (pyloromyotomy) ratified the diagnosis in all 8 children. They all were in good health after being operated. PMID:8146343

  4. [The sonographic diagnosis of hypertrophic stenosis of the pylorus].

    PubMed

    Rodríguez, R I; Briceño de Rodríguez, J A; Urrutia, M

    1993-05-01

    The clinical records of 18 children were studied, between 15 and 60 days old. They were hospitalized due to vomiting and diagnosis of suspected pyloric hypertrophic stenosis (PHS). The sonography confirmed the diagnosis in 8 children, by the thickening of the muscular layer and enlargement of the pyloric canal. The surgery (pyloromyotomy) ratified the diagnosis in all 8 children. They all were in good health after being operated. PMID:8327749

  5. Nd:YAG Laser Treatment of Keloids and Hypertrophic Scars

    PubMed Central

    Akaishi, Satoshi; Koike, Sachiko; Dohi, Teruyuki; Kobe, Kyoko; Hyakusoku, Hiko; Ogawa, Rei

    2012-01-01

    Pathological cutaneous scars such as keloids and hypertrophic scars (HSs) are characterized by a diffuse redness that is caused by the overgrowth of capillary vessels due to chronic inflammation. Our group has been using long-pulsed, 1064-nm Nd:YAG laser in noncontact mode with low fluence and a submillisecond pulse duration to treat keloids and hypertrophic scars since 2006 with satisfactory results. The present study examined the efficacy of this approach in 22 Japanese patients with keloids (n = 16) or hypertrophic scars (n = 6) who were treated every 3 to 4 weeks. Treatment settings were as follows: 5 mm spot size diameter; 14 J/cm2 energy density; 300 μs exposure time per pulse; and 10 Hz repetition rate. The responses of the pathological scars to the treatment were assessed by measuring their erythema, hypertrophy, hardness, itching, and pain or tenderness. Moreover, skin samples from 3 volunteer patients were subjected to histological evaluation and 5 patients underwent thermography during therapy. The average total scar assessment score dropped from 9.86 to 6.34. Hematoxylin and eosin staining and Elastica Masson-Goldner staining showed that laser treatment structurally changed the tissue collagen. This influence reached a depth of 0.5 to 1 mm. Electron microscopy revealed plasma protein leakage, proteoglycan particles, and a change in the collagen fiber fascicles. Further analyses revealed that noncontact mode Nd:YAG laser treatment is highly effective for keloids and hypertrophic scars regardless of patient age, the origin and multiplicity of scarring, the location of the scar(s), or the tension on the scar. PMID:22259645

  6. Monomelic hypertrophic osteoarthropathy secondary to aortic prosthesis infection.

    PubMed

    Hernández, M V; Antonio del Olmo, J; Orellana, C; Mestres, C A; Mũnoz-Gómez, J

    1995-01-01

    We describe a case of hypertrophic osteoarthropathy (HOA), exclusively located in the left lower leg and secondary to vascular prosthesis infection. Four years before, the patient underwent aortofemoral bifurcation grafting because of a ruptured aortic aneurysm. The investigations revealed prosthesis infection by Pseudomona aeruginosa and Bacteroides thetaiotamicron. The onset of HOA in a patient with a vascular prosthesis can help to achieve an early diagnosis of graft infection. The literature on this uncommon association is reviewed. PMID:7699670

  7. Stratified charge rotary engine for general aviation

    NASA Technical Reports Server (NTRS)

    Mount, R. E.; Parente, A. M.; Hady, W. F.

    1986-01-01

    A development history, a current development status assessment, and a design feature and performance capabilities account are given for stratified-charge rotary engines applicable to aircraft propulsion. Such engines are capable of operating on Jet-A fuel with substantial cost savings, improved altitude capability, and lower fuel consumption by comparison with gas turbine powerplants. Attention is given to the current development program of a 400-hp engine scheduled for initial operations in early 1990. Stratified charge rotary engines are also applicable to ground power units, airborne APUs, shipboard generators, and vehicular engines.

  8. Thermal laminarization of a stratified pipe flow

    SciTech Connect

    Oras, J.J.; Kasza, K.E.

    1984-01-01

    The present work constitutes a new program that grew out of a scoping assessment by ANL to determine the propensity for pipe stratification to occur in the reactor outlet nozzles and hot-leg piping of a generic LMFBR during events producing reverse pipe flow. This paper focuses on the role that thermal buoyancy plays relative to being able to laminarize a turbulent stratified shear zone in a horizontal pipe. The preceeding can influence the behavior of a pipe stratified-backflow-recirculation zone (cold plenum water down into the hot pipe flow) which developes as the result of a temperature difference between the pipe flow and the plenum.

  9. Mixing in thermally stratified energy stores

    SciTech Connect

    Berkle, J. van

    1996-10-01

    Two important aspects of short-term thermally stratified energy storage, thermocline mixing and thermocline thickness, are studied analytically, experimentally and numerically. The storage detrimental aspects are investigated for a simplified configuration, i.e., an adiabatic box containing a quasi-stationary thermocline. Numerical finite difference/volume simulations agree well with experiments. The dissipation-free 1D analytical model shows a large discrepancy. It appears that mixing inside thermally stratified stores is a two-state process. First fluid is withdrawn from the thermocline by viscous drag. Subsequent mixing takes place by stretching and folding of fluid particles, thereby enabling diffusion to become active. 17 refs., 10 figs., 2 tabs.

  10. Familial hypertrophic cardiomyopathy: vectorcardiographic findings in echocardiographically unaffected relative.

    PubMed Central

    Loperfido, F; Fiorilli, R; Digaetano, A; Di Gennaro, M; Santarelli, P; Bellocci, F; Coppola, E; Zecchi, P

    1982-01-01

    The electrocardiographic and vectorcardiographic (Frank system) features of the first degree relatives of subjects with documented familial hypertrophic cardiomyopathy were analysed. A total of nine affected members and 29 relatives were examined in four families. THe subjects were considered to be affected when the septal to free posterior wall thickness ratio exceeded 1.3 at M-mode echocardiography. Four relatives had asymmetric septal hypertrophy. Among 25 relatives without evidence of asymmetric septal hypertrophy, two over 20 years and 10 under 20 years of age showed increased voltage of QRS anterior forces (Qz amplitude greater than 0.80 mV) on the orthogonal electrocardiogram. The vectorcardiographic data of the relatives under 20 years of age without evidence of asymmetric septal hypertrophy (18 subjects) were compared with those of 38 normal control subjects of comparable age range. The young relatives without disproportionate septal hypertrophy had significantly greater Qz amplitude and Q/Rz ratio than the normal control subjects. In contrast, the echocardiographic data were not significantly different. We suggest that the electrocardiographic finding of abnormal anterior forces in one or more first degree relatives of subjects with documented hypertrophic cardiomyopathy may constitute a valuable aid in ascertaining the genetic transmission of the disease and in recognising affected members without echocardiographic evidence of hypertrophic cardiomyopathy. Images PMID:7200794

  11. Pregnancy related complications in women with hypertrophic cardiomyopathy

    PubMed Central

    Thaman, R; Varnava, A; Hamid, M S; Firoozi, S; Sachdev, B; Condon, M; Gimeno, J R; Murphy, R; Elliott, P M; McKenna, W J

    2003-01-01

    Objectives: To determine whether pregnancy is well tolerated in hypertrophic cardiomyopathy. Setting: Referral clinic. Design: The study cohort comprised 127 consecutively referred women with hypertrophic cardiomyopathy. Forty (31.5%) underwent clinical evaluation before pregnancy. The remaining 87 (68.5%) were referred after their first pregnancy. All underwent history, examination, electrocardiography, and echocardiography. Pregnancy related symptoms and complications were determined by questionnaire and review of medical and obstetric records where available. Results: There were 271 pregnancies in total. Thirty six (28.3%) women reported cardiac symptoms in pregnancy. Over 90% of these women had been symptomatic before pregnancy. Symptoms deteriorated during pregnancy in fewer than 10%. Of the 36 women with symptoms during pregnancy, 30 had further pregnancies. Symptoms reoccurred in 18 (60%); symptomatic deterioration was not reported. Heart failure occurred postnatally in two women (1.6%). No complications were reported in 19 (15%) women who underwent general anaesthesia and in 22 (17.4%) women who received epidural anaesthesia, three of whom had a significant left ventricular outflow tract gradient at diagnosis after pregnancy. Three unexplained intrauterine deaths occurred in women taking cardiac medication throughout pregnancy. No echocardiographic or clinical feature was a useful indicator of pregnancy related complications. Conclusions: Most women with hypertrophic cardiomyopathy tolerate pregnancy well. However, rare complications can occur and therefore planned delivery and fetal monitoring are still required for some patients. PMID:12807849

  12. A nude mouse model of hypertrophic scar shows morphologic and histologic characteristics of human hypertrophic scar.

    PubMed

    Momtazi, Moein; Kwan, Peter; Ding, Jie; Anderson, Colin C; Honardoust, Dariush; Goekjian, Serge; Tredget, Edward E

    2013-01-01

    Hypertrophic scar (HSc) is a fibroproliferative disorder that occurs following deep dermal injury. Lack of a relevant animal model is one barrier toward better understanding its pathophysiology. Our objective is to demonstrate that grafting split-thickness human skin onto nude mice results in survival of engrafted human skin and murine scars that are morphologically, histologically, and immunohistochemically consistent with human HSc. Twenty nude mice were xenografted with split-thickness human skin. Animals were euthanized at 30, 60, 120, and 180 days postoperatively. Eighteen controls were autografted with full-thickness nude mouse skin and euthanized at 30 and 60 days postoperatively. Scar biopsies were harvested at each time point. Blinded scar assessment was performed using a modified Manchester Scar Scale. Histologic analysis included hematoxylin and eosin, Masson's trichrome, toluidine blue, and picrosirius red staining. Immunohistochemistry included anti-human human leukocyte antigen-ABC, α-smooth muscle actin, decorin, and biglycan staining. Xenografted mice developed red, shiny, elevated scars similar to human HSc and supported by blinded scar assessment. Autograft controls appeared morphologically and histologically similar to normal skin. Xenografts survived up to 180 days and showed increased thickness, loss of hair follicles, adnexal structures and rete pegs, hypercellularity, whorled collagen fibers parallel to the surface, myofibroblasts, decreased decorin and increased biglycan expression, and increased mast cell density. Grafting split-thickness human skin onto nude mice results in persistent scars that show morphologic, histologic, and immunohistochemical consistency with human HSc. Therefore, this model provides a promising technique to study HSc formation and to test novel treatment options. PMID:23126488

  13. Flow and transport within a coastal aquifer adjacent to a stratified water body

    NASA Astrophysics Data System (ADS)

    Oz, Imri; Yechieli, Yoseph; Eyal, Shalev; Gavrieli, Ittai; Gvirtzman, Haim

    2016-04-01

    The existence of a freshwater-saltwater interface and the circulation flow of saltwater beneath the interface is a well-known phenomenon found at coastal aquifers. This flow is a natural phenomenon that occurs due to density differences between fresh groundwater and the saltwater body. The goals of this research are to use analytical, numerical, and physical models in order to examine the configuration of the freshwater-saltwater interface and the density-driven flow patterns within a coastal aquifer adjacent to long-term stratified saltwater bodies (e.g. meromictic lake). Such hydrological systems are unique, as they consist of three different water types: the regional fresh groundwater, and low and high salinity brines forming the upper and lower water layers of the stratified water body, respectively. This research also aims to examine the influence of such stratification on hydrogeological processes within the coastal aquifer. The coastal aquifer adjacent to the Dead Sea, under its possible future meromictic conditions, serves as an ideal example to examine these processes. The results show that adjacent to a stratified saltwater body three interfaces between three different water bodies are formed, and that a complex flow system, controlled by the density differences, is created, where three circulation cells are developed. These results are significantly different from the classic circulation cell that is found adjacent to non-stratified water bodies (lakes or oceans). In order to obtain a more generalized insight into the groundwater behavior adjacent to a stratified water body, we used the numerical model to perform sensitivity analysis. The hydrological system was found be sensitive to three dimensionless parameters: dimensionless density (i.e. the relative density of the three water bodies'); dimensionless thickness (i.e. the ratio between the relative thickness of the upper layer and the whole thickness of the lake); and dimensionless flux. The results

  14. Characteristics of Stratified Bedded Pack Dairy Manure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    "Compost" dairy barns are a relatively new housing system that generates a deep (0.9 to 1.5 m), stratified bedded pack (SBP) manure source. Bedding composed of sawdust, wood chips, or crop residues accumulates as additions are made to maintain a dry surface. Surface drying is promoted by a combinati...

  15. MERGING BUOYANT JETS IN A STRATIFIED CROSSFLOW

    EPA Science Inventory

    Some of the results of an extensive series of experiments to study the characteristics of merging, horizontally discharged buoyant jets in a linearly density stratified current are summarized. The experiments were conducted in a towing tank to simulate conditions typical of ocean...

  16. Oscillations in a Linearly Stratified Salt Solution

    ERIC Educational Resources Information Center

    Heavers, Richard M.

    2007-01-01

    Our physics students like to watch a ball bouncing underwater. They do this by dropping a weighted plastic ball into a 1000-ml cylinder filled with a linearly stratified salt-water solution at room temperature. The ball oscillates and comes to rest at about mid-depth. Its motion is analogous to the damped vertical oscillations of a mass hanging…

  17. Broadband acoustic quantification of stratified turbulence.

    PubMed

    Lavery, Andone C; Geyer, W Rockwell; Scully, Malcolm E

    2013-07-01

    High-frequency broadband acoustic scattering techniques have enabled the remote, high-resolution imaging and quantification of highly salt-stratified turbulence in an estuary. Turbulent salinity spectra in the stratified shear layer have been measured acoustically and by in situ turbulence sensors. The acoustic frequencies used span 120-600 kHz, which, for the highly stratified and dynamic estuarine environment, correspond to wavenumbers in the viscous-convective subrange (500-2500 m(-1)). The acoustically measured spectral levels are in close agreement with spectral levels measured with closely co-located micro-conductivity probes. The acoustically measured spectral shapes allow discrimination between scattering dominated by turbulent salinity microstructure and suspended sediments or swim-bladdered fish, the two primary sources of scattering observed in the estuary in addition to turbulent salinity microstructure. The direct comparison of salinity spectra inferred acoustically and by the in situ turbulence sensors provides a test of both the acoustic scattering model and the quantitative skill of acoustical remote sensing of turbulence dissipation in a strongly sheared and salt-stratified estuary. PMID:23862783

  18. Role of verapamil in preventing and treating hypertrophic scars and keloids.

    PubMed

    Wang, Ru; Mao, Yu; Zhang, Zhenyu; Li, Zhengyong; Chen, Junjie; Cen, Ying

    2016-08-01

    Keloid and hypertrophic scars are difficult to manage and remain a therapeutic challenge. Verapamil has shown a great potential in the management of keloid and hypertrophic scars. Comparing with conventional corticosteroid injections, verapamil could improve the appearance of keloid and hypertrophic scars, and is associated with a lower incidence of adverse effects. Is verapamil an effective alternative modality in the prevention and treatment of keloid and hypertrophic scars? The aim of this study was to assess the effectiveness of verapamil in preventing and treating keloid and hypertrophic scars. Searches were conducted in Medline, EMbase and Cochrane databases from 1974 to January 2015. The selection of articles was limited to human subjects. Five randomised controlled trials (RCTs) or cluster-randomised trials or controlled clinical trials (CCTs) comparing the efficacy of verapamil with conventional treatments were identified. The results showed that verapamil could improve keloid and hypertrophic scars, and was not significantly different from conventional corticosteroid injections. Few adverse effects were observed. However, this result should be considered carefully, as most of the included studies have a high risk of bias because of issues with randomization, allocation concealment, blinding, incomplete outcomes and selective reporting. In conclusion, verapamil could act as an effective alternative modality in the prevention and treatment of keloid and hypertrophic scars. More high-quality, multiple-centre, large-sample (RCTs) are required to define the role of verapamil in preventing and treating keloid and hypertrophic scars. PMID:25968157

  19. Thallium-201 imaging in a patient with mid-ventricular hypertrophic obstructive cardiomyopathy

    SciTech Connect

    Wakasugi, S.; Shibata, N.; Kobayashi, T.; Fudemoto, Y.; Hasegawa, Y.; Nakano, S.

    1988-10-01

    Findings specific to mid-ventricular hypertrophic obstructive cardiomyopathy were obtained in a patient by means of /sup 201/Tl planar myocardial scintigraphy. Namely, a myocardial band-like image dividing the left ventricle into two chambers was clearly shown. This was identified as hypertrophic muscle with sphincter-like muscular stenosis at the mid portion of the left ventricle.

  20. Wakes of Maneuvering Bodies in Stratified Fluids

    NASA Astrophysics Data System (ADS)

    Voropayev, S. I.; Fernando, H. J.

    2007-05-01

    We present the results of experimental/theoretical studies on large momentum eddies generated in late wakes of unsteady moving self-propelled bodies in stratified fluids. The experiments were conducted with scaled submarine model at high Reynolds numbers (50,000), corresponding to the fully turbulent flow regime. Dye visualization and PIV were used for flow diagnostics. When a self-propelled body makes a maneuver, e.g. accelerates, it imparts net momentum on the surrounding fluid. We show that in a stratified fluid this leads to impulsive momentum wakes with large, long-lived coherent vortices in the late flows, which may be used as a signature for identification of submarine wakes in oceanic thermocline. First, we consider dynamics and properties of such wakes in a linearly stratified fluid and present a model that permits to predict the main flow characteristics. Second, we consider wakes in a two layer stratified fluid (analog of the upper ocean) and show that such wakes may penetrate to the water surface; we present a model for this phenomenon and propose criteria for the penetration of wake signatures to the water surface in terms of main governing parameters (signature contrast versus confinement number). Finally, we consider the evolution of such momentum wake eddies in the field of decaying background turbulence, which mimics the oceanic thermocline, and show that for the flow configuration studied the contrast number remains sufficiently large and detectable wake imprints survive for a long period of time. Some pertinent estimates for submarines cruising in the upper ocean are also given. For more details see [1-3]. This study was supported by grant from the Office of Naval Research. 1. Voropayev S.I., Fernando H.J.S., Smirnov S.A. & Morrison R.J. 2006. On surface signatures generated by submersed momentum sources. Phys. Fluids, under revision. 2. Voropayev S.I., Fernando H.J.S. & Morrison R.J. 2006. Dipolar eddies in a stratified turbulent flow. J. Fluid

  1. Stable isotope composition of Earth's large lakes

    NASA Astrophysics Data System (ADS)

    Jasechko, S.; Gibson, J. J.; YI, Y.; Birks, S. J.; Sharp, Z. D.

    2011-12-01

    Lakes cover about three percent of Earth's continental area. Large lakes can significantly influence lake shore and regional climates by increasing specific humidity during evaporation and by moderating air temperatures. Stable isotopes of oxygen and hydrogen can be used to quantify lake evaporation, providing a supplementary and often cost-advantageous alternative to conventional hydrologic approaches that require over lake monitoring. Further, stable isotopes in lake sediments are an established tool in paleolimnology; however, interpreting changes to a lake's past isotope composition requires a comprehensive understanding of contemporary controls. Here, δ18O and δ2H values of water in modern lakes exceeding roughly five hundred square kilometres are compiled (n > 35). Voluminous and seasonally mixed lakes - such as the North American Great Lakes - have the most homogenous stable isotope compositions, while perennially-stratified and shallow lakes show greater variability. A rudimentary stable isotope mass balance is used to assess evaporation fluxes from large lakes on Earth. The approach taken simultaneously constrains evaporation outputs for both oxygen and hydrogen stable isotopes by accounting for lake effects on the overlying atmosphere. Model development highlights important considerations such as isotopic stratification (Tanganyika), disequilibrium isotopic mass balances (Baikal), and non-steady hydrologic balances. Further, the isotope composition of Earth's continental surface water reservoir is calculated. This value - weighted to volume - is δ18O = -7.5±1.7 per mille relative to standard mean ocean water. The compiled data may be a useful tracer of continental evaporate in global atmospheric water cycle studies and could be coupled to climate models capable of incorporating oxygen-18 and deuterium tracers to improve or validate calculations of lake effects on regional water cycling.

  2. A Novel Triple Medicine Combination Injection for the Resolution of Keloids and Hypertrophic Scars

    PubMed Central

    Gold, Michael H.

    2014-01-01

    Keloids and hypertrophic scars remain one of the more difficult treatment concerns for clinicians. A variety of therapies have been used in the past with moderate success. On occasion, combination therapy has been used to treat these lesion, in an attempt to lessen the symptoms of pain and pruritus that often accompanies keloids and hypertrophic scars, as well as treating the actual lesions themselves. A novel triple combination injection process is introduced here in an attempt to further reduce the signs and symptoms of these lesions. The combination includes 5-fluoruracil, triamcinolone acetonide, and hyaluronidase. All three work in concert to treat keloids and hypertrophic scars, and this is the first work at looking at these medicines given together, at the same time, in a series of recalcitrant keloids and hypertrophic scars. The positive results warrant further investigation and hope for those with keloids and hypertrophic scars. PMID:25489380

  3. Deglacial and lake level fluctuation history recorded in cores, Beaver Lake, Upper Peninsula, Michigan

    USGS Publications Warehouse

    Fisher, Timothy G.; Whitman, Richard L.

    1999-01-01

    Sediment cores collected from the littoral and pelagic zones of Beaver Lake, Michigan record fluctuations in the water level of Lake Superior. Beaver Lake is a small 300 ha lake in Pictured Rocks National Lakeshore (PRNL) now separated from Lake Superior by a dune-capped barrier bar. Cores were collected using a vibracorer from a lake-ice platform in February 1997. A 2.85 m long core in 10 m of water contains well-sorted sand, rhythmites, peat, interbedded sand and gyttja, and is capped with 1 m of massive gyttja. A 9480 BP AMS age from the basal sand provides a minimum deglacial date for the area. Further analysis indicates a sand-dominated depositional environment from a low lake stand at approximately 8500 BP to present. An approximate 8800 BP red to gray sediment color transition records either the cessation of meltwater input from Lake Agassiz or receding ice, while a younger similarly colored transition, 6600 BP in age, likely records sediment reworking in the coastal zone. Four AMS ages on peat range from 8520 to 7340 BP and are indicative of the Houghton low phase. Burial of the peat by stratified sand and gyttja after 7340 BP indicates a rising lake level. Peat at a higher level in the lake basin, encountered in shallow littoral cores, ranges in age from 6800 to 6420 BP, which estimates a 0.91 m rise/century in lake level to the Nipissing level by 5000 BP.

  4. Stably Stratified Flow in a Shallow Valley

    NASA Astrophysics Data System (ADS)

    Mahrt, L.

    2016-07-01

    Stratified nocturnal flow above and within a small valley of approximately 12-m depth and a few hundred metres width is examined as a case study, based on a network of 20 sonic anemometers and a central 20-m tower with eight levels of sonic anemometers. Several regimes of stratified flow over gentle topography are conceptually defined for organizing the data analysis and comparing with the existing literature. In our case study, a marginal cold pool forms within the shallow valley in the early evening but yields to larger ambient wind speeds after a few hours, corresponding to stratified terrain-following flow where the flow outside the valley descends to the valley floor. The terrain-following flow lasts about 10 h and then undergoes transition to an intermittent marginal cold pool towards the end of the night when the larger-scale flow collapses. During this 10-h period, the stratified terrain-following flow is characterized by a three-layer structure, consisting of a thin surface boundary layer of a few metres depth on the valley floor, a deeper boundary layer corresponding to the larger-scale flow, and an intermediate transition layer with significant wind-directional shear and possible advection of lee turbulence that is generated even for the gentle topography of our study. The flow in the valley is often modulated by oscillations with a typical period of 10 min. Cold events with smaller turbulent intensity and duration of tens of minutes move through the observational domain throughout the terrain-following period. One of these events is examined in detail.

  5. Sports and Exercise in Athletes with Hypertrophic Cardiomyopathy.

    PubMed

    Alpert, Craig; Day, Sharlene M; Saberi, Sara

    2015-07-01

    Hypertrophic cardiomyopathy (HCM) is the most common genetic cardiovascular disease and one of the most common causes of sudden cardiac death (SCD). Current guidelines restrict the participation of patients with HCM in competitive sports, limiting the health benefits of exercise. However, many individuals with HCM have safely participated in sports, with a low incidence of SCD. Improved stratification of patients and desired activity may allow most individuals with HCM to engage in physical activity safely. Therefore, physicians should create an individualized approach in guiding each patient with HCM eager to enjoy the benefits of physical activity in a safe manner. PMID:26100424

  6. Pseudoidiopathic hypertrophic subaortic stenosis in a patient with cardiac tamponade.

    PubMed

    Pandi, A S; Kronik, G

    1987-04-01

    A 53-year-old woman with a large pericardial effusion and tamponade presented with signs of IHSS including a grade 4/6 apical systolic murmur, severe SAM, early systolic aortic valve closure and a small hypercontractile left ventricle but at most borderline left ventricular hypertrophy. Following pericardiocentesis, the clinical and echocardiographic signs of subvalvular obstruction resolved completely. One year later the patient died of bronchial carcinoma and no evidence of hypertrophic cardiomyopathy was found at autopsy. Pericardial tamponade should be added to the list of possible causes of dynamic subvalvular obstruction in a structurally normal heart. PMID:3829760

  7. Evolution of a forced stratified mixing layer

    NASA Astrophysics Data System (ADS)

    Rotter, J.; Fernando, H. J. S.; Kit, E.

    2007-06-01

    Laboratory measurements were carried out in a spatially developing stably stratified shear layer generated downstream of a splitter plate. The instabilities were controlled using a flapper spanning the entire shear layer, with the flapper forced at the fastest growing frequency of the primary [Kelvin-Helmholtz (KH)] instability. The measurements were taken as the KH instabilities roll up, break down, and degenerate into stratified turbulence. Both stratified and homogeneous shear layers were considered, the latter acting as the "baseline" case. The measurements included the streamwise and vertical velocities (made using X-wire hot film probes), which allowed calculation of the mean and rms velocities, turbulent kinetic energy (TKE) dissipation, and TKE production. The density and its gradients were measured using miniature conductivity probes. The measurements and flow visualization elicited interesting features of KH evolution, namely that KH billows may be turbulent from the onset, the TKE dissipation is largest at early stages of evolution, the production of TKE is a maximum at the breakdown of billows, the decay of turbulence to fossilized motions and concomitant formation of fine (layered) structure occur rapidly after the breakdown of billows, and episodic rebirth of (zombie) turbulence develops before a final permanently fossilized state is achieved.

  8. Gravity-driven intrusions in stratified fluids

    NASA Astrophysics Data System (ADS)

    Maurer, Benjamin Dudley

    All natural fluids stratify. Stable stratifications, in which isobars and isopycnals are parallel, are capable of supporting internal wave motion. Unstable stratification, in which density and pressure gradients are not aligned, results in gravity-driven flow. Gravity currents are a subset of these flows in which horizontal density gradients sharpen and propagate horizontally, transporting mass, momentum, and energy. If the density of the gravity current is within the density extrema of the stably stratified ambient fluid, it propagates as an intrusion at an intermediate height. Through laboratory experiments and numerical simulations, this dissertation explores the influence of stratification on the dynamics of gravity-driven intrusions. Intrusions require stable stratification in the ambient fluid, which is capable of transporting momentum and energy away from the current in the form of internal waves. We investigate the constant velocity propagation of well-mixed intrusions propagating into a linearly stratified ambient fluid. Varying the level of neutral buoyancy, we quantify the corresponding variation in structure, momentum, and energy of the upstream wave field. Adjacent stable stratifications of differing vertical density structure necessarily entail horizontal density gradients. These gradients determine the hydrostatic pressure differences driving the ensuing gravity current. We examine the mid-depth, constant velocity propagation of one linearly stratified fluid into another more strongly linearly stratified fluid. Working from the available potential energy of the system and measurements of the intrusion thickness, we develop an energy model to describe the speed of the intrusion in terms of the ratio of the two buoyancy frequencies. Distinct from adjacent linear stratifications, adjacent discrete stratifications may create flow consisting of interleaving intrusions. Single intrusions into a two-layer ambient fluid are well understood. Limiting our

  9. CONNECTICUT LAKES

    EPA Science Inventory

    This is a 1:24,000-scale datalayer of named lakes in Connecticut. It is a polygon Shapefile that includes all lakes that are named on the U.S. Geologicial Survey (USGS) 7½ minute topographic quadrangle maps that cover the State of Connecticut, plus other officially named lakes i...

  10. Lake Powell

    Atmospheric Science Data Center

    2014-05-15

    article title:  Lake Powell     View Larger Image ... (14.42 mb)   This true-color image over Lake Powell was acquired by Multi-angle Imaging SpectroRadiometer (MISR) in late March 2000. Lake Powell was formed with the construction of the Glen Canyon Dam in 1963, on the ...

  11. Lake Eyre

    Atmospheric Science Data Center

    2013-04-16

    ...   View Larger Image Lake Eyre is a large salt lake situated between two deserts in one of Australia's driest regions. ... the effect of sunglint at the nadir camera view angle. Dry, salt encrusted parts of the lake appear bright white or gray. Purple areas have ...

  12. Effects of spatial allocation and parameter variability on lakewide estimates from surveys of Lake Superior, North America’s largest lake

    EPA Science Inventory

    Lake Superior was sampled in 2011 using a Generalized Random Tessellation Stratified design (n=54 sites) to characterize biological and chemical properties of this huge aquatic resource, with statistical confidence. The lake was divided into two strata (inshore <100m and offsh...

  13. Restrictive myocardium with an unusual pattern of apical hypertrophic cardiomyopathy.

    PubMed

    Sato, Takuma; Matsuyama, Taka-Aki; Seguchi, Osamu; Murata, Yoshihiro; Sunami, Haruki; Yanase, Masanobu; Fujita, Tomoyuki; Ishibashi-Ueda, Hatsue; Nakatani, Takeshi

    2015-01-01

    Loeffler endocarditis is a fibrous restrictive cardiomyopathy thought to be caused by persistent eosinophilia. It is difficult to diagnose, and the prognosis is often poor if the underlying eosinophilia is not promptly recognized and treated. We describe the case of a middle-aged woman treated for hypertrophic cardiomyopathy first detected during a routine check-up at age 35years but whose symptoms gradually progressed over the next 14years. Right ventricular biopsy showed extensive fibrosis of the endocardial tissue, and right heart catheterization revealed right heart failure and a low cardiac output state. Ultimately, she became reliant on inotropic and mechanical cardiovascular support, but we were not able to bridge her to transplant. Autopsy findings were typical of endocardial fibroelastosis, but she had not suffered from any tropical disease or traveled to high-risk areas. The presence of abnormal capillary proliferation suggested a diagnosis of Loeffler endocarditis. Nonetheless, apart from a 6-month period of eosinophilia 7years before her death, a history of well-controlled asthma and several drug sensitivities, we were unable to definitively identify the disease trigger. It is critical to diagnose and treat the underlying eosinophilia of Loeffler endocarditis to avoid a poor prognosis. This case highlights the importance of considering the diagnosis of eosinophilic endomyocarditis in patients with an unusual pattern of apical hypertrophic cardiomyopathy (or myocardial fibrosis of unknown etiology), even when there is no apparent history of eosinophilia. PMID:25804825

  14. ANCA-Associated Systemic Vasculitis Presenting With Hypertrophic Spinal Pachymeningitis

    PubMed Central

    Li, Xia; Zhao, Jiuliang; Wang, Qian; Fei, Yunyun; Zhao, Yan

    2015-01-01

    Abstract Reports of hypertrophic pachymeningitis associated with myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA) localized exclusively in the spine were quite rare. Two cases of ANCA-associated systemic vasculitis (AASV) presenting with hypertrophic spinal pachymeningitis (HSP) causing low back pain and numbness are described. Two patients showed prominent systemic and local inflammatory reactions manifested as fever, elevated levels of erythrocyte sedimentation rate and C-reactive protein, and markedly increased levels of total protein of cerebrospinal fluid. The gadolinium (Gd)-enhanced T1-weighted magnetic resonance imaging scan of spinal cord demonstrated diffuse spinal dura matter thickening. Additionally, simple microscopic hematuria was found in 1 case suggestive of renal involvement and the other 1 complicated with interstitial lung disease. Then, a diagnosis of HSP secondary to AASV was made. Combination therapy of corticosteroids and cyclophosphamide produced a rapid improvement in the clinical symptoms and laboratory parameters. Followed up for 6 months, 1 case relapsed when the dosage of prednisone was tapered to 10 mg daily. Since the patient refused rituximab-based regimen, an immunosuppressive triple-therapy (corticosteroid, cyclophosphamide, and azathioprine) was initiated and brought control of the disease during the subsequent 6 months of follow-up. HSP is a relatively rare form of central nervous system involvement of AASV. Early recognition and intervention are of great significance since the pathogenesis of HSP starts with an inflammatory and fibrosing process. PMID:26579814

  15. Subaortic and midventricular obstructive hypertrophic cardiomyopathy with extreme segmental hypertrophy

    PubMed Central

    Efthimiadis, Georgios K; Giannakoulas, Georgios; Parcharidou, Despina G; Ziakas, Antonios G; Papadopoulos, Christodoulos E; Karoulas, Takis; Pliakos, Christodoulos; Parcharidis, Georgios

    2007-01-01

    Background Subaortic and midventricular hypertrophic cardiomyopathy in a patient with extreme segmental hypertrophy exceeding the usual maximum wall thickness reported in the literature is a rare phenomenon. Case Presentation A 19-year-old man with recently diagnosed hypertrophic cardiomyopathy (HCM) was referred for sudden death risk assessment. The patient had mild exertional dyspnea (New York Heart Association functional class II), but without syncope or chest pain. There was no family history of HCM or sudden death. A two dimensional echocardiogram revealed an asymmetric type of LV hypertrophy; anterior ventricular septum = 49 mm; posterior ventricular septum = 20 mm; anterolateral free wall = 12 mm; and posterior free wall = 6 mm. The patient had 2 types of obstruction; a LV outflow obstruction due to systolic anterior motion of both mitral leaflets (Doppler-estimated 38 mm Hg gradient at rest); and a midventricular obstruction (Doppler-estimated 43 mm Hg gradient), but without apical aneurysm or dyskinesia. The patient had a normal blood pressure response on exercise test and no episodes of non-sustained ventricular tachycardia in 24-h ECG recording. Cardiac MRI showed a gross late enhancement at the hypertrophied septum. Based on the extreme degree of LV hypertrophy and the myocardial hyperenhancement, an implantation of a cardioverter-defibrillator was recommended prophylactically for primary prevention of sudden death. Conclusion Midventricular HCM is an infrequent phenotype, but may be associated with an apical aneurysm and progression to systolic dysfunction (end-stage HCM). PMID:17349063

  16. The KCNE genes in hypertrophic cardiomyopathy: a candidate gene study

    PubMed Central

    2011-01-01

    Background The gene family KCNE1-5, which encode modulating β-subunits of several repolarising K+-ion channels, has been associated with genetic cardiac diseases such as long QT syndrome, atrial fibrillation and Brugada syndrome. The minK peptide, encoded by KCNE1, is attached to the Z-disc of the sarcomere as well as the T-tubules of the sarcolemma. It has been suggested that minK forms part of an "electro-mechanical feed-back" which links cardiomyocyte stretching to changes in ion channel function. We examined whether mutations in KCNE genes were associated with hypertrophic cardiomyopathy (HCM), a genetic disease associated with an improper hypertrophic response. Results The coding regions of KCNE1, KCNE2, KCNE3, KCNE4, and KCNE5 were examined, by direct DNA sequencing, in a cohort of 93 unrelated HCM probands and 188 blood donor controls. Fifteen genetic variants, four previously unknown, were identified in the HCM probands. Eight variants were non-synonymous and one was located in the 3'UTR-region of KCNE4. No disease-causing mutations were found and no significant difference in the frequency of genetic variants was found between HCM probands and controls. Two variants of likely functional significance were found in controls only. Conclusions Mutations in KCNE genes are not a common cause of HCM and polymorphisms in these genes do not seem to be associated with a propensity to develop arrhythmia PMID:21967835

  17. Family communication in a population at risk for hypertrophic cardiomyopathy.

    PubMed

    Batte, Brittany; Sheldon, Jane P; Arscott, Patricia; Huismann, Darcy J; Salberg, Lisa; Day, Sharlene M; Yashar, Beverly M

    2015-04-01

    Encouraging family communication is an integral component of genetic counseling; therefore, we sought to identify factors impacting communication to family members at risk for Hypertrophic Cardiomyopathy (HCM). Participants (N = 383) completed an online survey assessing: 1) demographics (gender, genetic test results, HCM family history, and disease severity); 2) illness representations; 3) family functioning and cohesiveness; 4) coping styles; 5) comprehension of HCM autosomal dominant inheritance; and 6) communication of HCM risk information to at-risk relatives. Participants were a national sample of individuals with HCM, recruited through the Hypertrophic Cardiomyopathy Association. Data from 183 participants were analyzed using a logistic regression analysis, with family communication as a dichotomous dependent variable. We found that female gender and higher comprehension of autosomal dominant inheritance were significant predictors of participants' communication of HCM risk information to all their siblings and children. Our results suggest that utilizing interventions that promote patient comprehension (e.g., a teaching-focused model of genetic counseling) are important and may positively impact family communication within families with HCM. PMID:25304619

  18. Waves in stratified geomaterials with sliding layers

    NASA Astrophysics Data System (ADS)

    Pasternak, Elena; Dyskin, Arcady

    2016-04-01

    Wave propagation in stratified geomaterials with sliding layers is strongly anisotropic. The simplest representation of this behaviour is an elastic transverse-isotropic (orthotropic in 2D) continuum. Such a model is however only applicable when loading that is sufficiently uniform or when the wavelength is much larger than the layer thickness. In this case the stress non-uniformity over the layer thickness and the associated layer bending can be neglected. In an intermediate case when the wavelength is still higher than the layer thickness but not as high to neglect the stress non-uniformity at least bending moments and layer bending need to be taken into account. This is equivalent to retaining only the linear term of the normal stress variation over the layer thickness. The layer bending creates additional, rotational degrees of freedom. In 2D only one rotational degree of freedom exists, which considerably simplifies the modelling. The corresponding rotation is represented by the average gradient of layer deflection. The presence of rotations makes the stress tensor non-symmetrical. On top of that the rotation gradient creates moment stresses, which represent bending moments over the unit area in the layer cross-section. This requires the use of a 2D orthotropic Cosserat continuum to model the dynamics of such a stratified geomaterial. We show that in the stratified geomaterial shear-bending waves propagate. We determine the wave velocities and demonstrate that as the resistance to sliding reduces, the waves tend to localise over a line normal to the layering.

  19. Stably stratified canopy flow in complex terrain

    NASA Astrophysics Data System (ADS)

    Xu, X.; Yi, C.; Kutter, E.

    2015-07-01

    Stably stratified canopy flow in complex terrain has been considered a difficult condition for measuring net ecosystem-atmosphere exchanges of carbon, water vapor, and energy. A long-standing advection error in eddy-flux measurements is caused by stably stratified canopy flow. Such a condition with strong thermal gradient and less turbulent air is also difficult for modeling. To understand the challenging atmospheric condition for eddy-flux measurements, we use the renormalized group (RNG) k-ϵ turbulence model to investigate the main characteristics of stably stratified canopy flows in complex terrain. In this two-dimensional simulation, we imposed persistent constant heat flux at ground surface and linearly increasing cooling rate in the upper-canopy layer, vertically varying dissipative force from canopy drag elements, buoyancy forcing induced from thermal stratification and the hill terrain. These strong boundary effects keep nonlinearity in the two-dimensional Navier-Stokes equations high enough to generate turbulent behavior. The fundamental characteristics of nighttime canopy flow over complex terrain measured by the small number of available multi-tower advection experiments can be reproduced by this numerical simulation, such as (1) unstable layer in the canopy and super-stable layers associated with flow decoupling in deep canopy and near the top of canopy; (2) sub-canopy drainage flow and drainage flow near the top of canopy in calm night; (3) upward momentum transfer in canopy, downward heat transfer in upper canopy and upward heat transfer in deep canopy; and (4) large buoyancy suppression and weak shear production in strong stability.

  20. Smad ubiquitination regulatory factor 2 expression is enhanced in hypertrophic scar fibroblasts from burned children

    PubMed Central

    Finnerty, Celeste C; He, Jing; Herndon, David N

    2013-01-01

    Transforming growth factor-β1 (TGF-β1) plays a key role in hypertrophic scar formation. A lot of studies have shown that TGF-β1 stimulates fibroblast proliferation, collagen production, and α-smooth muscle actin (α-SMA) expression, inhibits matrix degradation and eventually leads to scar formation. Smad proteins are important intracellular mediators of TGF-β1 signaling, and Smad ubiquitination regulatory factor 2 (Smurf2), an ubiquitin ligase for Smads, plays critical roles in the regulation of TGF-β1/Smad signaling. It was reported that Smurf2 was abnormally expressed during the process of liver fibrosis and lung fibrosis. Hypertrophic scarring is a fibroproliferative disorder of the dermis that occurs following wounding. However, little is known about the expression of Smurf2 in hypertrophic scarring. We hypothesized that TGF-β1 signaling cannot be disrupted after wound epithelialization probably due to abnormal expression of Smurf2 in hypertrophic scar fibroblasts. In the present study, we found that hypertrophic scar fibroblasts exhibited increased Smurf2 protein and mRNA levels compared with normal fibroblasts, and the expression of Smurf2 gradually increased in hypertrophic scar fibroblasts after TGF-β1 stimulation. Furthermore, we transfected Smurf2 siRNA into hypertrophic scar fibroblasts, and we found that silencing the expression of Smurf2 in hypertrophic scar fibroblasts dramatically reduced TGF-β1 production, inhibited TGF-β1-induced α-SMA expression and inhibited TGF-β1-induced collagen I synthesis. Our results suggest that the enhanced expression of Smurf2 is involved in the progression of hypertrophic scarring. PMID:21920670

  1. Diffuse reflection coefficient of a stratified sea.

    PubMed

    Haltrin, V I

    1999-02-20

    A differential equation of a Riccati type for the diffuse reflection coefficient of a stratified sea is proposed. For a homogeneous sea with arbitrary inherent optical properties this equation is solved analytically. For an inhomogeneous sea it is solved approximately for any arbitrary stratification. The resulting equation expresses the diffuse reflection coefficient of the sea through vertical profiles of absorption and backscattering coefficients, bottom albedo, and sea depth. The results of calculations with this equation are compared with Monte Carlo computations. It was found that the precision of this approach is in the range of 15%. PMID:18305694

  2. White dwarf stars with chemically stratified atmospheres

    NASA Technical Reports Server (NTRS)

    Muchmore, D.

    1982-01-01

    Recent observations and theory suggest that some white dwarfs may have chemically stratified atmospheres - thin layers of hydrogen lying above helium-rich envelopes. Models of such atmospheres show that a discontinuous temperature inversion can occur at the boundary between the layers. Model spectra for layered atmospheres at 30,000 K and 50,000 K tend to have smaller decrements at 912 A, 504 A, and 228 A than uniform atmospheres would have. On the basis of their continuous extreme ultraviolet spectra, it is possible to distinguish observationally between uniform and layered atmospheres for hot white dwarfs.

  3. A Filtering Method For Gravitationally Stratified Flows

    SciTech Connect

    Gatti-Bono, Caroline; Colella, Phillip

    2005-04-25

    Gravity waves arise in gravitationally stratified compressible flows at low Mach and Froude numbers. These waves can have a negligible influence on the overall dynamics of the fluid but, for numerical methods where the acoustic waves are treated implicitly, they impose a significant restriction on the time step. A way to alleviate this restriction is to filter out the modes corresponding to the fastest gravity waves so that a larger time step can be used. This paper presents a filtering strategy of the fully compressible equations based on normal mode analysis that is used throughout the simulation to compute the fast dynamics and that is able to damp only fast gravity modes.

  4. Internal wave solitons. [in stratified fluids

    NASA Technical Reports Server (NTRS)

    Meiss, J. D.; Pereira, N. R.

    1978-01-01

    Attention is given to the Benjamin-Ono equation for waves within a stratified fluid, i.e., internal waves. Numerical computations indicate soliton-like behavior since solitary waves pass through each other upon collision. In addition, two and three Lorentzian solitons are noted to pass through one another. An initial Lorentzian having an amplitude larger than soliton amplitude is observed to decay into solitons. The velocities of these solitons may be predicted by conservation laws. Future work will be directed toward determining exact solutions.

  5. Abnormalities of the Mitral Apparatus in Hypertrophic Cardiomyopathy: Echocardiographic, Pathophysiologic, and Surgical Insights.

    PubMed

    Silbiger, Jeffrey J

    2016-07-01

    Hypertrophic cardiomyopathy is a genetic disorder characterized by increased cardiac muscle mass. This disorder has broad phenotypic expression, including, among others, asymmetric septal hypertrophy, midcavity hypertrophy, and apical hypertrophy. In recent years, it has been recognized that hypertrophic cardiomyopathy is not characterized solely by ventricular hypertrophy but that a number of abnormalities of the mitral apparatus (papillary muscles, leaflets, chords, and annulus) may also occur. These figure prominently in the echocardiographic evaluation and surgical planning of patients with hypertrophic cardiomyopathy and serve as the focus of this review. PMID:27146120

  6. Hearing Profile in Patients with Dilated and Hypertrophic Cardiomyopathies

    PubMed Central

    El-Zarea, Gehan Abd El-Rahman; Hassan, Yasser Elsayed Mohamed; Mahmoud, Ahmed Mohamed Ahmed

    2016-01-01

    Introduction Cardiomyopathy may cause disruptions in the micro-vascular system of the stria vascularis in the cochlea, and, subsequently, may result in cochlear degeneration. Degeneration in the stria vascularis affects the physical and chemical processes in the organ of Corti, thereby causing a possible hearing impairment. The objective of this study was to assess the hearing profiles of patients with dilated and hypertrophic cardiomyopathies to determine the relationship between the degree of hearing loss and the degree and duration of the disease and to compare the dilated and hypertrophic cardiomyopathies as regards hearing profile. Methods In this case control study, we studied 21 patients (cases/study group/group 1) and 15 healthy individuals (controls/group 2). Six patients (group 1a) had hypertrophic cardiomyopathy (HCM), and 15 patients (group 1b) had dilated cardiomyopathy (DCM). The data were analyzed using the t-test, chi-squared test, Kruskal-Wallis test, and the Multiple Mann-Whitney test. Results The results of this study showed that 80% of those patients with DCM (group 1b) had bilateral sensorineural hearing loss (SNHL), and 100% of the patients with HCM (group 1a) had mild to severe bilateral sloping SNHL. Distortion Product Otoacoustic Emissions (DPOAEs) were present in 14% of the study group and in 100 % of the control group. The results of the measurements of auditory brainstem response (ABR) showed that 50% of the study group had abnormal latencies compared to the control group, and there was no correlation between the duration of the disease and the degree of hearing loss or DPOAE. Fifty percent of the patients with HCM and 35% of the patients with DCM had positive family histories of similar conditions, and 35% of those with HCM had a positive family history of sudden death. Conclusion The results of this study suggested that the link between heart disease and hearing loss and early identification of hearing loss in patients with

  7. Jet-mixing of initially stratified flows

    NASA Astrophysics Data System (ADS)

    Wright, Stuart; Markides, Christos; Matar, Omar

    2015-11-01

    Low pipeline velocities in the oil-and-gas industry generally lead to liquid-liquid flows stratifying due to density differences. Pipeline stratified flows inherently have no single point for sub-sampling and phase slip leads to in situ phase fractions differing from input volume fractions. Establishing representative or average properties and phase fractions is therefore difficult for industry. This leads to sampling errors through measurement uncertainty. In-line mixing overcomes liquid-liquid stratification, establishing a liquid-liquid dispersion that minimises slip between phases. Here, we use jets-in-crossflow (JICF) as a means of mixing. We present results of CFD simulations using the volume-of- fluid method that demonstrate the breakup of stratification as a result of the application of JICF. A number of simple jet configurations are described, and their effectiveness in generating dispersions is compared. We also present preliminary experimental results based on the use of a matched-refractive-index method, laser-induced fluorescence, particle-tracking- and particle-image-velocimetry. Funding from Cameron for Ph.D. studentship (SW) gratefully acknowledged.

  8. Stratified coastal ocean interactions with tropical cyclones

    NASA Astrophysics Data System (ADS)

    Glenn, S. M.; Miles, T. N.; Seroka, G. N.; Xu, Y.; Forney, R. K.; Yu, F.; Roarty, H.; Schofield, O.; Kohut, J.

    2016-03-01

    Hurricane-intensity forecast improvements currently lag the progress achieved for hurricane tracks. Integrated ocean observations and simulations during hurricane Irene (2011) reveal that the wind-forced two-layer circulation of the stratified coastal ocean, and resultant shear-induced mixing, led to significant and rapid ahead-of-eye-centre cooling (at least 6 °C and up to 11 °C) over a wide swath of the continental shelf. Atmospheric simulations establish this cooling as the missing contribution required to reproduce Irene's accelerated intensity reduction. Historical buoys from 1985 to 2015 show that ahead-of-eye-centre cooling occurred beneath all 11 tropical cyclones that traversed the Mid-Atlantic Bight continental shelf during stratified summer conditions. A Yellow Sea buoy similarly revealed significant and rapid ahead-of-eye-centre cooling during Typhoon Muifa (2011). These findings establish that including realistic coastal baroclinic processes in forecasts of storm intensity and impacts will be increasingly critical to mid-latitude population centres as sea levels rise and tropical cyclone maximum intensities migrate poleward.

  9. High frequency scattering from corrugated stratified cylinders

    NASA Technical Reports Server (NTRS)

    Sarabandi, Kamal; Ulaby, Fawwaz T.

    1991-01-01

    Interest in applying radar remote sensing for the study of forested areas led to the development of a model for scattering from corrugated stratified dielectric cylinders. The model is used to investigate the effect of bark and its roughness on scattering from tree trunks and branches. The outer layer of the cylinder (bark) is assumed to be a low-loss dielectric material and to have a regular (periodic) corrugation pattern. The inner layers are treated as lossy dielectrics with smooth boundaries. A hybrid solution based on the moment method and the physical optics approximation is obtained. In the solution, the corrugations are replaced with polarization currents that are identical to those of the local tangential periodic corrugated surface, and the stratified cylinder is replaced with equivalent surface currents. New expressions for the equivalent physical-optics currents are used which are more convenient than the standard ones. It is shown that the bark layer and its roughness both reduce the radar cross-section. It is also demonstrated that the corrugations can be replaced by an equivalent anisotropic layer.

  10. Stratified coastal ocean interactions with tropical cyclones

    PubMed Central

    Glenn, S. M.; Miles, T. N.; Seroka, G. N.; Xu, Y.; Forney, R. K.; Yu, F.; Roarty, H.; Schofield, O.; Kohut, J.

    2016-01-01

    Hurricane-intensity forecast improvements currently lag the progress achieved for hurricane tracks. Integrated ocean observations and simulations during hurricane Irene (2011) reveal that the wind-forced two-layer circulation of the stratified coastal ocean, and resultant shear-induced mixing, led to significant and rapid ahead-of-eye-centre cooling (at least 6 °C and up to 11 °C) over a wide swath of the continental shelf. Atmospheric simulations establish this cooling as the missing contribution required to reproduce Irene's accelerated intensity reduction. Historical buoys from 1985 to 2015 show that ahead-of-eye-centre cooling occurred beneath all 11 tropical cyclones that traversed the Mid-Atlantic Bight continental shelf during stratified summer conditions. A Yellow Sea buoy similarly revealed significant and rapid ahead-of-eye-centre cooling during Typhoon Muifa (2011). These findings establish that including realistic coastal baroclinic processes in forecasts of storm intensity and impacts will be increasingly critical to mid-latitude population centres as sea levels rise and tropical cyclone maximum intensities migrate poleward. PMID:26953963

  11. Transition phenomena in unstably stratified turbulent flows.

    PubMed

    Bukai, M; Eidelman, A; Elperin, T; Kleeorin, N; Rogachevskii, I; Sapir-Katiraie, I

    2011-03-01

    We study experimentally and theoretically the transition phenomena caused by external forcing from Rayleigh-Bénard convection with large-scale circulation (LSC) to the limiting regime of unstably stratified turbulent flow without LSC, where the temperature field behaves like a passive scalar. In the experiments we use the Rayleigh-Bénard apparatus with an additional source of turbulence produced by two oscillating grids located near the sidewalls of the chamber. When the frequency of the grid oscillations is larger than 2 Hz, the LSC in turbulent convection is destroyed, and the destruction of the LSC is accompanied by a strong change of the mean temperature distribution. However, in all regimes of the unstably stratified turbulent flow the ratio [(ℓ{x}∇{x}T)²+(ℓ{y}∇{y}T)² + (ℓ{z}∇{z}T)²]/<θ²> varies slightly (even in the range of parameters where the behavior of the temperature field is different from that of the passive scalar). Here ℓ{i} are the integral scales of turbulence along the x,y,z directions, and T and θ are the mean and fluctuating parts of the fluid temperature. At all frequencies of the grid oscillations we have detected long-term nonlinear oscillations of the mean temperature. The theoretical predictions based on the budget equations for turbulent kinetic energy, turbulent temperature fluctuations, and turbulent heat flux, are in agreement with the experimental results. PMID:21517582

  12. Stratified coastal ocean interactions with tropical cyclones.

    PubMed

    Glenn, S M; Miles, T N; Seroka, G N; Xu, Y; Forney, R K; Yu, F; Roarty, H; Schofield, O; Kohut, J

    2016-01-01

    Hurricane-intensity forecast improvements currently lag the progress achieved for hurricane tracks. Integrated ocean observations and simulations during hurricane Irene (2011) reveal that the wind-forced two-layer circulation of the stratified coastal ocean, and resultant shear-induced mixing, led to significant and rapid ahead-of-eye-centre cooling (at least 6 °C and up to 11 °C) over a wide swath of the continental shelf. Atmospheric simulations establish this cooling as the missing contribution required to reproduce Irene's accelerated intensity reduction. Historical buoys from 1985 to 2015 show that ahead-of-eye-centre cooling occurred beneath all 11 tropical cyclones that traversed the Mid-Atlantic Bight continental shelf during stratified summer conditions. A Yellow Sea buoy similarly revealed significant and rapid ahead-of-eye-centre cooling during Typhoon Muifa (2011). These findings establish that including realistic coastal baroclinic processes in forecasts of storm intensity and impacts will be increasingly critical to mid-latitude population centres as sea levels rise and tropical cyclone maximum intensities migrate poleward. PMID:26953963

  13. SNOHATS: Stratified atmospheric turbulence over snow surfaces

    NASA Astrophysics Data System (ADS)

    Parlange, M. B.; Bou-Zeid, E.; Huwald, H.; Chamecki, M.; Meneveau, C.

    2006-12-01

    Stably stratified flows present particular challenges for both experimental and numerical studies of the atmosphere and its interaction with the underlying surfaces. Turbulence damping and gravity waves are just two examples of stable flow features that complicate the application of turbulence similarity theories and the formulation of effective turbulence models for subgrid-scales in Large Eddy Simulation (LES). To address these concerns, a field study (SNOHATS) was held at the extensive "Plaine-Morte" glacier in the Swiss Alps (3000 m) from February to April 2006. The snow covered surface is constantly colder than the air guaranteeing stable conditions over long periods. Two horizontal arrays of vertically separated 3D sonic anemometers were deployed. This setup was specifically designed to measure subgrid scale fluxes (upwind uninterrupted fetch of 2 km) and then to assess the success of various models in reproducing these fluxes. We first study the influence of stratification on the spectra and co-spectra of velocity and temperature. Then, we compare dissipation computed using the second order and third order structure functions to the SGS dissipation. Subsequently, the eddy viscosity subgrid scale model is assessed for LES of stably stratified atmospheric flows. Specifically, we measure the Smagorinsky coefficient and the SGS turbulent Prandtl number by matching measured and modeled dissipation rates. Finally, we present the dependence of these coefficients on stability, height above the ground, filter size, and strain rates. Results are compared to previously reported data for stable flows over soil surfaces (HATS, Kleissl et al., 2004; Horst et al., 2004).

  14. Energy transfer in stably stratified turbulence

    NASA Astrophysics Data System (ADS)

    Kimura, Yoshifumi; Herring, Jackson

    2015-11-01

    Energy transfer in forced stable stratified turbulence is investigated using pseudo-spectral DNS of the Navier-Stokes equations under the Boussinesq approximation with 10243 grid points. Making use of the Craya-Herring decomposition, the velocity field is decomposed into vortex (Φ1) and wave (Φ2) modes. To understand the anisotropy of stably stratified turbulence, the energy flues in terms of the spherical, the horizontal and the vertical wave numbers, are investigated for the total kinetic, Φ1, Φ2 energies, respectively. Among the three fluxes, the spherical and the horizontal look similar for strong stratification, and Φ1 flux shows a wave number region of constant value, which implies Kolmogorov's inertial range. The corresponding spectral power are, however, k - 5 / 2 for the spherical and k⊥- 5 / 3 for the horizontal cases. In contrast to these, the vertical energy fluxes show completely different features. We have observed the saturation spectrum E (kz) ~ CN2kz-3 for strong stratification as before, but the mechanism to produce this spectrum seems different from the Kolmogorov picture.

  15. Measurement of High Reynolds Number Near-Field Turbulent Sphere Wakes under Stratified Conditions

    NASA Astrophysics Data System (ADS)

    Kalumuck, Kenneth; Brandt, Alan; Decker, Kirk; Shipley, Kara

    2015-11-01

    To characterize the near-field of a stratified wake at Reynolds numbers, Re = 2 x 105 - 106, experiments were conducted with a large diameter (0.5 m) sphere towed through a thermally stratified fresh water lake. Stratification produced BV frequencies, N, up to 0.07/s (42 cph) resulting in Froude numbers F = U/ND >= 15. The submerged sphere and associated instrumentation including two Acoustic Doppler Velocimeters (ADVs) and an array of fast response thermistors were affixed to a common frame towed over a range of speeds. Three components of the instantaneous wake velocities were obtained simultaneously at two cross-wake locations with the ADVs while density fluctuations were inferred from temperature measurements made by the thermistors. These measurements were used to determine the mean, rms, and spectra of all three components of the turbulent velocity field and density fluctuations at multiple locations. The turbulence power spectra follow the expected -5/3 slope with wavenumber. Existing stratified near-field wake data for spheres are for Re =104 and less, and only a very limited set of data under unstratified conditions exists at these large values of Re. Those data are primarily measurements of the sphere drag, surface pressure distribution, and separation rather than in wake turbulence. Advances in CFD modeling have enabled simulations at these high Reynolds numbers without quantitative data available for validation. Sponsored by ONR Turbulence and Wakes program.

  16. Distinguishing Hypertrophic Cardiomyopathy-Associated Mutations from Background Genetic Noise

    PubMed Central

    Kapplinger, Jamie D.; Landstrom, Andrew P.; Bos, J. Martijn; Salisbury, Benjamin A.; Callis, Thomas E.; Ackerman, Michael J.

    2014-01-01

    Despite the significant progress that has been made in identifying disease-associated mutations, the utility of the Hypertrophic Cardiomyopathy (HCM) genetic test is limited by a lack of understanding of the background genetic variation inherent to these sarcomeric genes in seemingly healthy subjects. This study represents the first comprehensive analysis of genetic variation in 427 ostensibly healthy individuals for the HCM genetic test using the “Gold Standard” Sanger sequencing method validating the background rate identified in the publically available exomes. While mutations are clearly over-represented in disease, a background rate as high as ~5% among healthy individuals prevents diagnostic certainty. To this end, we have identified a number of estimated predictive value-based associations including gene-specific, topology, and conservation methods generating an algorithm aiding in the probabilistic interpretation of an HCM genetic test. PMID:24510615

  17. Surgery Management of Rare Hypertrophic Frenum in an Infant

    PubMed Central

    Stroppa, Sheila de Carvalho; da Silva, Juliana Yassue Barbosa; Tavares, Maria Cristina Reis; Duda, João Gilberto; Losso, Estela Maris

    2014-01-01

    To report a rare case of a lateral frenum hypertrophy in an infant, this paper describes the case of a girl who came to a first dental appointment when she was 4 months old. A hypertrophic lateral frenum in the upper left canine region was detected. A great depression in the gingival rodet separated the anterior maxillary segment from the posterior one and also decreased the lip mobility in this region. A frenectomy was performed when the patient was 11 months old and the clinical follow-up was done up to the age of 30 months. There was normalization in the vestibular insertion of the lateral frenum, lip mobility, physiological development of the maxilla, and eruption of the upper incisors, canines, and first primary molars. Infants should go to a dental examination precociously in order to detect possible congenital and development alterations. PMID:25180104

  18. Cerebrovascular complications associated with idiopathic hypertrophic subaortic stenosis.

    PubMed

    Furlan, A J; Craciun, A R; Raju, N R; Hart, N

    1984-01-01

    One hundred fifty patients with idiopathic hypertrophic subaortic stenosis (IHSS) were followed-up for an average of 5.5 years. There were 95 males and 55 females with a mean age of 51 years. Patients usually presented with cardiac symptoms or syncope; no patient presented with stroke. Eight patients (5%) died during follow-up, all from cardiac causes. Eleven patients (7%) developed cerebrovascular complications; 5 (3%) had a stroke and 6 (4%) had TIA only. Patients with IHSS and atrial fibrillation have a much greater stroke risk. Mitral annulus calcification may also increase stroke risk in IHSS. However, stroke is almost never the presenting manifestation of IHSS, and the longterm risk of stroke for most patients with known IHSS is low. PMID:6538354

  19. Recent advances in diagnosis and management of hypertrophic cardiomyopathy

    PubMed Central

    Siswanto, B B; Aryani, R

    2009-01-01

    Hypertrophic cardiomyopathy (HCM) is characterised by a thickened but non-dilated left ventricle in the absence of another cardiac or systemic condition capable of producing the magnitude of hypertrophy evident. It is the most common familial genetic disease of the heart (1/500 to 1/1000), as well as the most common cause of sudden cardiac death in young people and athletes. Survival rates of patients with HCM have improved from the 1960s onwards. Natural history in patients with HCM might vary from developing severe heart failure or atrial fibrillation, some die suddenly, often at a young age and in the absence of previous symptoms. Because of its heterogeneous clinical course and expression, HCM frequently presents uncertainty and represents a management dilemma to cardiovascular specialists and other practitioners.

  20. Ehlers-Danlos Syndrome associated with cardiomyopathy hypertrophic obstructive.

    PubMed

    Pinto, Raimundo José Almeida de Oliveira; Santos, Adaílton Araújo dos; Azevedo, Mablo de Castro; Meira, Saulo Sacramento

    2015-01-01

    Ehlers-Danlos syndrome is a rare clinical condition caused by a genetic change that results in the formation of structurally or functionally altered collagen. The clinical manifestations are varied, being the most obvious skin hypermotility and increased joint flexibility, although other systems - such as cardiovascular, respiratory and neurological - may also be affected. This paper presents the report of a patient who sought medical attention with complaints of atypical chest pain. Clinical evaluation enabled hypothetical diagnosis of hypertrophic obstructive cardiomyopathy and Ehlers-Danlos syndrome. Initial electrocardiogram, echocardiogram and 24 hours holter allowed the confirmation of the first hypothesis. A skin biopsy performed later associated clinical data and confirmed the second hypothesis. PMID:26312722

  1. Pressure therapy for hypertrophic scarrings: preliminary communication1

    PubMed Central

    Robertson, J C; Druett, J E; Hodgson, B; Druett, Jane

    1980-01-01

    A six-point programme for the prevention and pressure therapy of hypertrophic scarring started in 1975 at Odstock Hospital. The work reported here includes a pressure calibration of batches of the material chosen for pressure bandaging; a pressure study of the bandages on volunteers' limbs; and the formation of a pressure therapy clinic. The clinic results were similar to those reported by Thomson (1974) and were considered sufficiently favourable to justify continuing the clinic and instituting a policy of close review and early therapy for all burns patients. The programme proved the accuracy of the pressure sensor and attempted to develop an objective method of recording progress. Arguments for pressure versus occlusion as the therapeutic agent are discussed and supported by a case report. It is suggested that a controlled trial of pressure therapy should be carried out. PMID:7241460

  2. Keloids and Hypertrophic Scars: A Spectrum of Clinical Challenges.

    PubMed

    Trace, Anthony P; Enos, Clinton W; Mantel, Alon; Harvey, Valerie M

    2016-06-01

    Since their earliest description, keloids and hypertrophic scars have beleaguered patients and clinicians alike. These scars can be aesthetically disfiguring, functionally debilitating, emotionally distressing, and psychologically damaging, culminating in a significant burden for patients. Our current understanding of keloid pathophysiology has grown and continues to advance while molecular biology, genetics, and technology provide ever-deepening insight into the nature of wound healing and the pathologic perturbations thereof. Greater understanding will lead to the development and application of refined therapeutic modalities. This article provides an overview of our current understanding of keloids, highlighting clinical characteristics and diagnostic criteria while providing a comprehensive summary of the many therapeutic modalities available. The proposed mechanism, application, adverse events, and reported efficacy of each modality is evaluated, and current recommendations are summarized. PMID:26894654

  3. Ehlers-Danlos Syndrome associated with cardiomyopathy hypertrophic obstructive*

    PubMed Central

    Pinto, Raimundo José Almeida de Oliveira; dos Santos, Adaílton Araújo; Azevedo, Mablo de Castro; Meira, Saulo Sacramento

    2015-01-01

    Ehlers-Danlos syndrome is a rare clinical condition caused by a genetic change that results in the formation of structurally or functionally altered collagen. The clinical manifestations are varied, being the most obvious skin hypermotility and increased joint flexibility, although other systems - such as cardiovascular, respiratory and neurological - may also be affected. This paper presents the report of a patient who sought medical attention with complaints of atypical chest pain. Clinical evaluation enabled hypothetical diagnosis of hypertrophic obstructive cardiomyopathy and Ehlers-Danlos syndrome. Initial electrocardiogram, echocardiogram and 24 hours holter allowed the confirmation of the first hypothesis. A skin biopsy performed later associated clinical data and confirmed the second hypothesis. PMID:26312722

  4. Hypertrophic osteoarthropathy in patient with Crohn's disease: a case report.

    PubMed

    Rhee, Sung-Min; Park, Ki Jeong; Ha, Yong-Chan

    2014-05-01

    Numerous causes of hypertrophic osteoarthropathy (HOA) have been reported. Commonly, secondary osteoarthropathy accompanies pulmonary diseases such as carcinoma of the lung, pleural tumors, lung abscesses, and bronchiectasis. However, HOA in inflammatory bowel disease is a rare complication. There are only a few reports of secondary HOA with Crohn's disease. Our purpose was to report another case of HOA in Crohn's disease. We describe a case of a 27-year-old man with underlying Crohn's disease presenting with 2 years of pain in multiple joints. Radiographic findings suggested HOA in extremities. We performed a conservative treatment including medication and rehabilitations. The patient's symptoms were much improved at the latest follow-up. Although numerous studies on HOA have been published, the pathogenesis of HOA is still unclear. Various treatment modalities were recommended but further studies to uncover the pathogenesis of HOA with Crohn's disease and to establish a treatment modality are needed. PMID:25025001

  5. Clinical utility of natriuretic peptides and troponins in hypertrophic cardiomyopathy.

    PubMed

    Kehl, Devin W; Buttan, Anshu; Siegel, Robert J; Rader, Florian

    2016-09-01

    The diagnosis of hypertrophic cardiomyopathy (HCM) is based on clinical, echocardiographic and in some cases genetic findings. However, prognostication remains limited except in the subset of patients with high-risk indicators for sudden cardiac death. Additional methods are needed for risk stratification and to guide clinical management in HCM. We reviewed the available data regarding natriuretic peptides and troponins in HCM. Plasma levels of natriuretic peptides, and to a lesser extent serum levels of troponins, correlate with established disease markers, including left ventricular thickness, symptom status, and left ventricular hemodynamics by Doppler measurements. As a reflection of left ventricular filling pressure, natriuretic peptides may provide an objective measure of the efficacy of a specific therapy. Both natriuretic peptides and troponins predict clinical risk in HCM independently of established risk factors, and their prognostic power is additive. Routine measurement of biomarker levels therefore may be useful in the clinical evaluation and management of patients with HCM. PMID:27236124

  6. Hypertrophic pulmonary osteoarthropathy demonstrated on SPECT/CT.

    PubMed

    Russo, Robert R; Lee, Allen; Mansberg, Robert; Emmett, Louise

    2009-09-01

    A 51-year-old man with a known history of hepatic cirrhosis and a right lung mass presented with hemoptysis and widespread bone pain. Sputum cytology demonstrated atypical cells. A CT scan of the chest demonstrated a 3-cm spiculating mass in the right lower lobe, in addition to nodules in both upper lobes and lymphadenopathy within the mediastinum and both hila. Skeletal scintigraphy was performed to assess for metastatic bone disease, and demonstrated increased tracer uptake along the cortex of the distal femurs bilaterally. There was also low-grade cortical uptake in the mid femur and tibia bilaterally on planar imaging. SPECT/CT was able to improve the specificity of the planar scintigraphic findings, by confirming tracer uptake was localized to the periosteum as expected for hypertrophic pulmonary osteoarthropathy, thereby excluding the presence of skeletal metastases. PMID:19692832

  7. Abnormal skeletal muscle bioenergetics in familial hypertrophic cardiomyopathy.

    PubMed Central

    Thompson, C. H.; Kemp, G. J.; Taylor, D. J.; Conway, M.; Rajagopalan, B.; O'Donoghue, A.; Styles, P.; McKenna, W. J.; Radda, G. K.

    1997-01-01

    OBJECTIVE: To determine the skeletal muscle metabolic manifestations of familial hypertrophic cardiomyopathy. DESIGN: A case-control study. SETTING: 31P magnetic resonance spectroscopy of the calf muscle was performed on volunteers from a centre specialising in familial hypertrophic cardiomyopathy. PATIENTS: Five patients with abnormal beta myosin heavy chain protein in cardiac and skeletal muscle and five patients with a troponin T abnormality in cardiac muscle were compared with healthy controls. RESULTS: High energy phosphate metabolism in vivo was examined in a non-invasive manner. In resting muscle, the beta myosin heavy chain group had a higher ratio of phosphocreatine to ATP concentration (4.51 (SD 0.17)) than either the troponin T group (3.88 (0.42)) or controls (n = 16; 4.04 (0.40)). Exercise duration was reduced compared to controls, and during the fourth minute of exercise phosphocreatine depletion and muscle acidification were greater in both patient groups. After exercise, the recovery of phosphocreatine-an index of oxidative metabolic capacity of the muscle-was slower in the beta myosin heavy chain group (mean half time 0.65 (0.08) minutes) than in the troponin T group (0.60 (0.17) minutes) or controls (0.48 (0.14) minutes). CONCLUSIONS: Exercise metabolism was abnormal in both groups of subjects, and the affected contractile protein determined the metabolic changes in muscle at rest and during recovery. In patients with abnormal beta myosin heavy chain protein, there was a decrease in oxidative capacity consistent with the reduction in mitochondria reported in muscle biopsy studies of similar patients. PMID:9326994

  8. Obstruction is unimportant in the pathophysiology of hypertrophic cardiomyopathy.

    PubMed Central

    Criley, J. M.; Siegel, R. J.

    1986-01-01

    There has been a longstanding controversy about the significance of intracavitary pressure gradients in hypertrophic cardiomyopathy (HCM). It has been generally assumed that the gradient is the result of an 'obstruction' that impedes left ventricular outflow and which can be relieved by operative intervention. In the first decade after the discovery of HCM (1957-66), the site of 'obstruction' was thought to be a muscular sphincter or contraction ring in the submitral region of the left ventricle, and operations designed to emulate pyloromyectomy (for hypertrophic pyloric stenosis) were developed. Following a challenge to the existence of the 'contraction ring' and an alternative non-obstructive explanation of the pressure gradient, the site of 'obstruction' was translocated to a point of apposition between the anterior mitral leaflet and the interventricular septum, a result of systolic anterior motion (SAM) of the mitral valve. Despite the translocation of the site and mechanism of 'obstruction', the operation for 'relief of obstruction' has not changed significantly. The newer site of 'obstruction' has been challenged on the grounds that the ventricle is not demonstrably impeded in its emptying; when a gradient is provoked, the ventricle empties more rapidly and more completely than it does without a gradient. In addition to a non-obstructive explanation of the gradient, other phenomena thought to be indicative of 'obstruction' can be explained by rapid and complete emptying of the ventricle (cavitary obliteration). Since the morbidity and mortality of symptomatic HCM patients without pressure gradients may exceed that of patients with pressure gradients, it is suggested that 'obstruction' may be unimportant in the pathophysiology of HCM and attention should be focused on abnormal diastolic function and life threatening arrhythmias. Images Figure 4 Figure 8b PMID:3534838

  9. DDD pacing in hypertrophic cardiomyopathy: a multicentre clinical experience.

    PubMed Central

    Slade, A. K.; Sadoul, N.; Shapiro, L.; Chojnowska, L.; Simon, J. P.; Saumarez, R. C.; Dodinot, B.; Camm, A. J.; McKenna, W. J.; Aliot, E.

    1996-01-01

    BACKGROUND--DDD pacing has been advocated as an effective treatment for drug refractory obstructive hypertrophic cardiomyopathy. This study reports the outcome of pacing in 56 patients with refractory symptoms referred to four tertiary centres. METHODS--Core data on symptoms, drug burden, and left ventricular outflow tract gradient were recorded. Patients underwent a temporary pacing study with optimisation of the atrioventricular (AV) delay for greatest gradient reduction without haemodynamic compromise. Patients were assessed after implantation in terms of changes in symptoms, drug load, and outflow tract gradient. RESULTS--56 patients underwent pacing assessment. The mean (SD) left ventricular outflow tract gradient before pacing was 78 (31) mm Hg. At temporary study the mean (SD) left ventricular outflow tract gradient was 38 (24) mm Hg with a median (range) optimised sensed AV delay of 65 (25-125) ms. Fifty three patients were implanted and followed up for a mean (SD) of 11 (11) months. The median (range) programmed sensed AV delay was 60 (31-200) ms. Left ventricular outflow tract gradient at follow up was 36 (25) mm Hg. Forty four patients had improved functional class. Although a correlation (r = 0.69) was shown between acute and chronic left ventricular outflow tract gradient reduction, there was no correlation between magnitude of gradient reduction and functional improvement, and no appreciable change in pharmacological burden. CONCLUSION--This series confirms symptomatic improvement after DDD pacing in hypertrophic cardiomyopathy. There remains, however, a discrepancy between perceived symptomatic benefit and modest objective improvement. Furthermore, the optimal outcome has been achieved only with continued pharmacological treatment. Current methods of temporary evaluation do not predict functional outcome which seems to be independent of the magnitude of gradient reduction. PMID:8624871

  10. Echo-guided transaortic left ventricular myotomy for idiopathic hypertrophic subaortic stenosis.

    PubMed

    Nitta, S; Yambe, T; Nitta, K; Katahira, Y; Saijo, Y; Sonobe, T; Naganuma, S; Kakinuma, Y; Tanaka, M; Miura, M

    1991-12-01

    Idiopathic hypertrophic subaortic stenosis (IHSS) is a progressive cardiac disease known to induce sudden death occasionally. The authors tested echocardiography as a method of guiding myotomy, and observed its clinical usefulness as a safe surgical procedure for IHSS. PMID:1843048

  11. Sudden death following AV node ablation in a man with Fabry disease mimicking hypertrophic cardiomyopathy.

    PubMed

    Rodda, Odette A; Lynch, Matthew; Parsons, Sarah

    2016-08-01

    We present a case of Fabry disease with an uncommon pattern of asymmetrical hypertrophy with septal prominence resulting in an erroneous diagnosis of hypertrophic cardilmyopathy clinically. The deceased presented for a medicolegal autopsy following his sudden death after an AV node ablation. Fabry disease continues to be an important misdiagnosis of hypertrophic cardiomyopathy in a clinical setting. Early diagnosis of Fabry disease is essential so that early treatment can be instituted. PMID:27213840

  12. Surgical Treatment of a 4-Year-Old Child with Hypertrophic Obstructive Cardiomyopathy: Case Report.

    PubMed

    Chen, Jin; Wu, Qingyu; Xu, Zhonghua; Kong, Xiangchen

    2016-01-01

    The incidence of pediatric hypertrophic obstructive cardiomyopathy is low. The lesions usually involve the left ventricle or ventricular septum, leading to either left or right ventricular outflow tract stenosis. However, combined left and right ventricular outflow tract stenosis is rare, and the surgical treatment is limited, especially in children. Surgery to release the obstruction was performed successfully in a 4-year-old child with right and left ventricular outflow tract obstruction together with a hypertrophic cardiomyopathy. The result was excellent. PMID:26913685

  13. Successful treatment of hypertrophic herpes simplex genitalis in HIV-infected patient with topical imiquimod.

    PubMed

    Deza, Gustavo; Martin-Ezquerra, Gemma; Curto-Barredo, Laia; Villar García, Judit; Pujol, Ramon M

    2015-12-01

    Hypertrophic herpes simplex genitalis is an atypical presentation of genital herpes described in the context of immunosuppression, particularly HIV-positive patients. This situation can become a diagnostic and therapeutic challenge. For this reason, alternative therapies are currently being discussed in the literature. We report a case of hypertrophic genital herpes in a HIV-positive patient who was successfully treated with topical 5% imiquimod after treatment failures with oral and i.v. antivirals. PMID:26074211

  14. Assessing iron dynamics in the release from a stratified reservoir

    USGS Publications Warehouse

    Ashby, S.L.; Faulkner, S.P.; Gambrell, R.P.; Smith, B.A.

    2004-01-01

    Field and laboratory studies were conducted to describe the fate of total, dissolved, and ferrous (Fe2.) iron in the release from a stratified reservoir with an anoxic hypolimnion. Concentrations of total iron in the tail water indicated a first order removal process during a low flow release (0.6 m3sec1), yet negligible loss was observed during a period of increased discharge (2.8 m 3 sec-1). Dissolved and ferrous iron concentrations in the tailwater were highly variable during both release regimes and did not follow responses based on theoretical predictions. Ferrous iron concentrations in unfiltered samples were consistently greater than concentrations observed in samples filtered separately through 0.4, 0.2, and 0.1 ??m filters. Total iron removal in laboratory studies followed first order kinetics, but was twice that rate (0.077 mg.L-1 .hr 1) observed during low flow discharge in the tailwater (0.036 mg. L1 .hr1). Dissolved and ferrous iron losses in laboratory studies were rapid (???75% in the first 15 minutes and 95% within 1 hour), followed theoretical predictions, and were much faster than observations in the tailwater (???30% within the first hour). The presence of particulate forms of ferrous iron in the field and differences in removal rates observed in field and laboratory studies indicate a need for improved field assessment techniques and consideration of complexation reactions when assessing the dynamics of iron in reservoir releases and downstream impacts as a result of operation regimes. ?? Copyright by the North American Lake Management Society 2004.

  15. Tomographic reconstruction of stratified fluid flow.

    PubMed

    Winters, K B; Rouseff, D

    1993-01-01

    A method for imaging a moving fluid is proposed and evaluated by numerical simulation. A cross-section of a three-dimensional fluid is probed by high-frequency acoustic waves from several different directions. Assuming straight-ray geometric acoustics, the time of flight depends on both the scaler sound speed and the vector fluid velocity. By appropriately combining travel times, projections of both the sound speed and the velocity are isolated. The sound speed is reconstructed using the standard filtered backprojection algorithm. Though complete inversion of velocity is not possible, sufficient information is available to recover the component of fluid vorticity transverse to the plane of insonification. A new filtered backprojection algorithm for vorticity is developed and implemented. To demonstrate the inversion procedure, a 3-D stratified fluid is simulated and travel time data are calculated by path integration. These data are then inverted to recover both the scaler sound speed and the vorticity of the evolving flow. PMID:18263153

  16. Plasmonics of graphene laced stratified media

    NASA Astrophysics Data System (ADS)

    Aparajita, Upali; Roslyak, Oleksiy

    Strong overlap of fields of graphene physics and photonics drawn a lot of attention recently. Not only graphene possesses intrinsic highly tunable plasmons but a combination of grapheme with noble metal nano structures promises a variety of existing applications for conventional plasmonics , such as novel optical devices working in a broad range from THz to visible spectra. We report simulations of those devices using combination of discrete dipole approximation (DDA) and boundary element methods (BEM). While DDA is an essential tool for modeling large molecule polarizabilities and scattering the BEM provides necessary Green's function tensors when those molecules are in close proximity to the nano-structures. As an example of that technique we study electron energy loss and Raman spectra for complex molecules in presence of metal plasmon active nano particles embedded into a stratified graphene laced medium.

  17. Emergence of helicity in rotating stratified turbulence

    NASA Astrophysics Data System (ADS)

    Marino, Raffaele; Mininni, Pablo D.; Rosenberg, Duane; Pouquet, Annick

    2013-03-01

    We perform numerical simulations of decaying rotating stratified turbulence and show, in the Boussinesq framework, that helicity (velocity-vorticity correlation), as observed in supercell storms and hurricanes, is spontaneously created due to an interplay between buoyancy and rotation common to large-scale atmospheric and oceanic flows. Helicity emerges from the joint action of eddies and of inertia-gravity waves (with inertia and gravity with respective associated frequencies f and N), and it occurs when the waves are sufficiently strong. For N/f<3 the amount of helicity produced is correctly predicted by a quasilinear balance equation. Outside this regime, and up to the highest Reynolds number obtained in this study, namely Re≈10000, helicity production is found to be persistent for N/f as large as ≈17, and for ReFr2 and ReRo2, respectively, as large as ≈100 and ≈24000.

  18. Domain Growth Kinetics in Stratifying Foam Films

    NASA Astrophysics Data System (ADS)

    Zhang, Yiran; Sharma, Vivek

    2015-03-01

    Baking bread, brewing cappuccino, pouring beer, washing dishes, shaving, shampooing, whipping eggs and blowing bubbles all involve creation of aqueous foam films. Typical foam films consist of two surfactant-laden surfaces that are μ 5 nm - 10 micron apart. Sandwiched between these interfacial layers is a fluid that drains primarily under the influence of viscous and interfacial forces, including disjoining pressure. Interestingly, for certain low molecular weight surfactants, a layered ordering of micelles inside the foam films (thickness <100 nm) leads to a stepwise thinning phenomena called stratification. We experimentally elucidate the influence of these different driving forces, and confinement on drainage kinetics of horizontal stratifying foam films. Thinner, darker domains spontaneously grow within foam films. Quantitative characterization of domain growth visualized in a using Scheludko-type thin film cell and a theoretical model based on lubrication analysis, provide critical insights into hydrodynamics of thin foam films, and the strength and nature of surface forces, including supramolecular oscillatory structural forces.

  19. Direct multiangle solution for poorly stratified atmospheres.

    PubMed

    Kovalev, Vladimir; Wold, Cyle; Petkov, Alexander; Hao, Wei Min

    2012-09-01

    The direct multiangle solution is considered, which allows improving the scanning lidar-data-inversion accuracy when the requirement of the horizontally stratified atmosphere is poorly met. The signal measured at zenith or close to zenith is used as a core source for extracting optical characteristics of the atmospheric aerosol loading. The multiangle signals are used as auxiliary data to extract the vertical transmittance profile from the zenith signal. Details of the retrieval methodology are considered that eliminate, or at least soften, some specific ambiguities in the multiangle measurements in horizontally heterogeneous atmospheres. Simulated and experimental elastic lidar data are presented that illustrate the essentials of the data-processing technique. Finally, the prospects of the utilization of high-spectral-resolution lidar in the multiangle mode are discussed. PMID:22945162

  20. Stably stratified canopy flow in complex terrain

    NASA Astrophysics Data System (ADS)

    Xu, X.; Yi, C.; Kutter, E.

    2014-11-01

    The characteristics of stably stratified canopy flows in complex terrain are investigated by employing the Renormalized Group (RNG) k-ɛ turbulence model. In this two-dimensional simulation, we imposed persistent constant heat flux at ground surface and linearly increasing cooling rate in the upper canopy layer, vertically varying dissipative force from canopy drag elements, buoyancy forcing induced from thermal stratification and the hill terrain. These strong boundary effects keep nonlinearity in the two-dimensional Navier-Stokes equations high enough to generate turbulent behavior. The fundamental characteristics of nighttime canopy flow over complex terrain measured by a few multi-tower advection experiments can be produced by this numerical simulation, such as: (1) unstable layer in the canopy, (2) super-stable layer associated with flow decoupling in deep canopy and near the top of canopy, (3) upward momentum transfer in canopy, and (4) large buoyancy suppression and weak shear production in strong stability.

  1. Stratified charge rotary engine combustion studies

    NASA Technical Reports Server (NTRS)

    Shock, H.; Hamady, F.; Somerton, C.; Stuecken, T.; Chouinard, E.; Rachal, T.; Kosterman, J.; Lambeth, M.; Olbrich, C.

    1989-01-01

    Analytical and experimental studies of the combustion process in a stratified charge rotary engine (SCRE) continue to be the subject of active research in recent years. Specifically to meet the demand for more sophisticated products, a detailed understanding of the engine system of interest is warranted. With this in mind the objective of this work is to develop an understanding of the controlling factors that affect the SCRE combustion process so that an efficient power dense rotary engine can be designed. The influence of the induction-exhaust systems and the rotor geometry are believed to have a significant effect on combustion chamber flow characteristics. In this report, emphasis is centered on Laser Doppler Velocimetry (LDV) measurements and on qualitative flow visualizations in the combustion chamber of the motored rotary engine assembly. This will provide a basic understanding of the flow process in the RCE and serve as a data base for verification of numerical simulations. Understanding fuel injection provisions is also important to the successful operation of the stratified charge rotary engine. Toward this end, flow visualizations depicting the development of high speed, high pressure fuel jets are described. Friction is an important consideration in an engine from the standpoint of lost work, durability and reliability. MSU Engine Research Laboratory efforts in accessing the frictional losses associated with the rotary engine are described. This includes work which describes losses in bearing, seal and auxillary components. Finally, a computer controlled mapping system under development is described. This system can be used to map shapes such as combustion chamber, intake manifolds or turbine blades accurately.

  2. Stratified scaffold design for engineering composite tissues.

    PubMed

    Mosher, Christopher Z; Spalazzi, Jeffrey P; Lu, Helen H

    2015-08-01

    A significant challenge to orthopaedic soft tissue repair is the biological fixation of autologous or allogeneic grafts with bone, whereby the lack of functional integration between such grafts and host bone has limited the clinical success of anterior cruciate ligament (ACL) and other common soft tissue-based reconstructive grafts. The inability of current surgical reconstruction to restore the native fibrocartilaginous insertion between the ACL and the femur or tibia, which minimizes stress concentration and facilitates load transfer between the soft and hard tissues, compromises the long-term clinical functionality of these grafts. To enable integration, a stratified scaffold design that mimics the multiple tissue regions of the ACL interface (ligament-fibrocartilage-bone) represents a promising strategy for composite tissue formation. Moreover, distinct cellular organization and phase-specific matrix heterogeneity achieved through co- or tri-culture within the scaffold system can promote biomimetic multi-tissue regeneration. Here, we describe the methods for fabricating a tri-phasic scaffold intended for ligament-bone integration, as well as the tri-culture of fibroblasts, chondrocytes, and osteoblasts on the stratified scaffold for the formation of structurally contiguous and compositionally distinct regions of ligament, fibrocartilage and bone. The primary advantage of the tri-phasic scaffold is the recapitulation of the multi-tissue organization across the native interface through the layered design. Moreover, in addition to ease of fabrication, each scaffold phase is similar in polymer composition and therefore can be joined together by sintering, enabling the seamless integration of each region and avoiding delamination between scaffold layers. PMID:25846397

  3. LAKE FORK

    EPA Science Inventory

    The Lake Fork of the Arkansas River Watershed has been adversely affected through mining, water diversion and storage projects, grazing, logging, and other human influences over the past 120 years. It is the goals of the LFWWG to improve the health of Lake fork by addressing th...

  4. Lake Constance

    Atmospheric Science Data Center

    2013-04-17

    ... Swiss shores of Lake Constance at the town of Rorschach. Eutrophication, or the process of nutrient enrichment, is rapidly accelerated ... of the value of Lake Constance, efforts to mitigate eutrophication were initiated in the 1970's. MISR was built and is managed ...

  5. The effect of surfactant on stratified and stratifying gas-liquid flows

    NASA Astrophysics Data System (ADS)

    Heiles, Baptiste; Zadrazil, Ivan; Matar, Omar

    2013-11-01

    We consider the dynamics of a stratified/stratifying gas-liquid flow in horizontal tubes. This flow regime is characterised by the thin liquid films that drain under gravity along the pipe interior, forming a pool at the bottom of the tube, and the formation of large-amplitude waves at the gas-liquid interface. This regime is also accompanied by the detachment of droplets from the interface and their entrainment into the gas phase. We carry out an experimental study involving axial- and radial-view photography of the flow, in the presence and absence of surfactant. We show that the effect of surfactant is to reduce significantly the average diameter of the entrained droplets, through a tip-streaming mechanism. We also highlight the influence of surfactant on the characteristics of the interfacial waves, and the pressure gradient that drives the flow. EPSRC Programme Grant EP/K003976/1.

  6. Lake Superior Phytoplankton Characterization from the 2006 Probability Based Survey

    EPA Science Inventory

    We conducted a late summer probability based survey of Lake Superior in 2006 which consisted of 52 sites stratified across 3 depth zones. As part of this effort, we collected composite phytoplankton samples from the epilimnion and the fluorescence maxima (Fmax) at 29 of the site...

  7. MicroRNA-21 Regulates hTERT via PTEN in Hypertrophic Scar Fibroblasts

    PubMed Central

    Su, Lin-Lin; Liu, Jia-Qi; Li, Yan; Shi, Ji-Hong; Cai, Wei-Xia; Bai, Xiao-Zhi; Jia, Yan-Hui; Zhao, Bin; Wu, Xue; Li, Jun; Hu, Da-Hai

    2014-01-01

    Background As an important oncogenic miRNA, microRNA-21 (miR-21) is associated with various malignant diseases. However, the precise biological function of miR-21 and its molecular mechanism in hypertrophic scar fibroblast cells has not been fully elucidated. Methodology/Principal Findings Quantitative Real-Time PCR (qRT-PCR) analysis revealed significant upregulation of miR-21 in hypertrophic scar fibroblast cells compared with that in normal skin fibroblast cells. The effects of miR-21 were then assessed in MTT and apoptosis assays through in vitro transfection with a miR-21 mimic or inhibitor. Next, PTEN (phosphatase and tensin homologue deleted on chromosome ten) was identified as a target gene of miR-21 in hypertrophic scar fibroblast cells. Furthermore, Western-blot and qRT-PCR analyses revealed that miR-21 increased the expression of human telomerase reverse transcriptase (hTERT) via the PTEN/PI3K/AKT pathway. Introduction of PTEN cDNA led to a remarkable depletion of hTERT and PI3K/AKT at the protein level as well as inhibition of miR-21-induced proliferation. In addition, Western-blot and qRT-PCR analyses confirmed that hTERT was the downstream target of PTEN. Finally, miR-21 and PTEN RNA expression levels in hypertrophic scar tissue samples were examined. Immunohistochemistry assays revealed an inverse correlation between PTEN and hTERT levels in high miR-21 RNA expressing-hypertrophic scar tissues. Conclusions/Significance These data indicate that miR-21 regulates hTERT expression via the PTEN/PI3K/AKT signaling pathway by directly targeting PTEN, therefore controlling hypertrophic scar fibroblast cell growth. MiR-21 may be a potential novel molecular target for the treatment of hypertrophic scarring. PMID:24817011

  8. Involvement of impaired desmosome-related proteins in hypertrophic scar intraepidermal blister formation.

    PubMed

    Tan, Jianglin; He, Weifeng; Luo, Gaoxing; Wu, Jun

    2015-11-01

    Hypertrophic scar is one of the unique fibrotic diseases in human. Intraepidermal blister is a common clinical symptom following the hypertrophic scar formation. However, little is known about the reason of blister creation. In this study, we selected three patients with hypertrophic scar as manifested by raised, erythematous, pruritic, blister and thickened appearance undergoing scar resection. The first scar sample was 6 months after burn from the neck of a 3 years old male patient with 10 score by Vancouver Scar Scale (VSS). The second scar sample was 12 months after burn from the dorsal foot of a 16 years old female patient with 13 score by VSS. The third one was 9 months after burn from the elbow of a 34 years old male patients with 13 score by VSS. In order to understand the molecular mechanism of blister formation, we screened the different protein expression between hypertrophic scar and normal skin tissue by means of isobaric tags for relative and absolute quantitation (iTRAQ) labeling technology and high throughput 2D LC-MS/MS. There were 48 proteins found to be downregulated in hypertrophic scar. Among the downregulated ones, plakophilin1 (PKP1), plakophilin3 (PKP3) and desmoplakin (DSP) were the desmosome-related proteins which were validated by immunohistochemistry and western blotting assay. Transmission electron microscopy further showed the considerably reduced size and intensity of hemidesmosome and desmosome in hypertrophic scar tissue, compared to control normal skin. Our data indicted for the first time that downregulation of DSP, PKP1 and PKP3 in hypertrophic scar might be responsible for intraepidermal blister formation. PMID:25922301

  9. STREAMLINES IN STRATIFIED FLOW OVER A THREE-DIMENSIONAL HILL

    EPA Science Inventory

    A fluid modeling study was performed in the EPA Fluid Modeling Facility's stratified towing tank to determine the effects of stratification on the flow field over a three-dimensional hill. Streamlines in the stratified flow over an axisymmetric hill were marked with a dye tracer ...

  10. Thermally unstable perturbations in stratified conducting atmospheres

    NASA Astrophysics Data System (ADS)

    Reale, Fabio; Serio, Salvatore; Peres, Giovanni

    1994-10-01

    We investigate the thermal stability of isobaric perturbations in a stratified isothermal background atmosphere with solar abundances, as resulting from the competition of optically thin plasma radiative cooling and of heating conducted from the surrounding atmosphere. We have analyzed the threshold line between stable and unstable perturbations, in the plane of the two important control parameters: the initial size of the perturbation and the temperature of the unperturbed medium; this line changes with the pressure of the unperturbed atmosphere. We have extended the results of linear perturbation analysis by means of numerical calculations of the evolution of spherical isobaric perturbations, using a two-dimensional hydrodynamic code including Spitzer heat conduction. We explore a wide range of the parameters appropriate to the solar and stellar upper atmospheres: the background uniform temperature is between 105 K and 107 K, the initial pressure betweeen 0.1 and 10 dyn/sq cm, and the perturbation size between 105 and 1010 cm. The numerical results are in substantial agreement with the linear analysis. We discuss possible implications of our results also in terms of observable effects, especially concerning plasma downflows, and propose thermal instability as a possible candidate to explain the observed redshifts in solar and stellar transition region lines.

  11. Aligning the economic value of companion diagnostics and stratified medicines.

    PubMed

    Blair, Edward D; Stratton, Elyse K; Kaufmann, Martina

    2012-01-01

    The twin forces of payors seeking fair pricing and the rising costs of developing new medicines has driven a closer relationship between pharmaceutical companies and diagnostics companies, because stratified medicines, guided by companion diagnostics, offer better commercial, as well as clinical, outcomes. Stratified medicines have created clinical success and provided rapid product approvals, particularly in oncology, and indeed have changed the dynamic between drug and diagnostic developers. The commercial payback for such partnerships offered by stratified medicines has been less well articulated, but this has shifted as the benefits in risk management, pricing and value creation for all stakeholders become clearer. In this larger healthcare setting, stratified medicine provides both physicians and patients with greater insight on the disease and provides rationale for providers to understand cost-effectiveness of treatment. This article considers how the economic value of stratified medicine relationships can be recognized and translated into better outcomes for all healthcare stakeholders. PMID:25562363

  12. Aligning the Economic Value of Companion Diagnostics and Stratified Medicines

    PubMed Central

    Blair, Edward D.; Stratton, Elyse K.; Kaufmann, Martina

    2012-01-01

    The twin forces of payors seeking fair pricing and the rising costs of developing new medicines has driven a closer relationship between pharmaceutical companies and diagnostics companies, because stratified medicines, guided by companion diagnostics, offer better commercial, as well as clinical, outcomes. Stratified medicines have created clinical success and provided rapid product approvals, particularly in oncology, and indeed have changed the dynamic between drug and diagnostic developers. The commercial payback for such partnerships offered by stratified medicines has been less well articulated, but this has shifted as the benefits in risk management, pricing and value creation for all stakeholders become clearer. In this larger healthcare setting, stratified medicine provides both physicians and patients with greater insight on the disease and provides rationale for providers to understand cost-effectiveness of treatment. This article considers how the economic value of stratified medicine relationships can be recognized and translated into better outcomes for all healthcare stakeholders. PMID:25562363

  13. Keloids and Hypertrophic Scars: Update and Future Directions

    PubMed Central

    Huang, Chenyu; Murphy, George F.; Akaishi, Satoshi

    2013-01-01

    Summary: The development of cutaneous pathological scars, namely, hypertrophic scars (HSs) and keloids, involves complex pathways, and the exact mechanisms by which they are initiated, evolved, and regulated remain to be fully elucidated. The generally held concepts that keloids and HSs represent “aberrant wound healing” or that they are “characterized by hyalinized collagen bundles” have done little to promote their accurate clinicopathological classification or to stimulate research into the specific causes of these scars and effective preventative therapies. To overcome this barrier, we review here the most recent findings regarding the pathology and pathogenesis of keloids and HSs. The aberrations of HSs and keloids in terms of the inflammation, proliferation, and remodeling phases of the wound healing process are described. In particular, the significant roles that the extracellular matrix and the epidermal and dermal layers of skin play in scar pathogenesis are examined. Finally, the current hypotheses of pathological scar etiology that should be tested by basic and clinical investigators are detailed. Therapies that have been found to be effective are described, including several that evolved directly from the aforementioned etiology hypotheses. A better understanding of pathological scar etiology and manifestations will improve the clinical and histopathological classification and treatment of these important lesions. PMID:25289219

  14. Idiopathic Hypertrophic Cranial Pachymeningitis Misdiagnosed as Acute Subtentorial Hematoma

    PubMed Central

    Park, Ik-Seong; Kim, Hoon; Chung, Eun Yong

    2010-01-01

    A case of idiopathic hypertrophic cranial pachymeningitis (IHCP) misdiagnosed as an acute subdural hematoma is reported. A 37-year-old male patient presented with headache following head trauma 2 weeks earlier. Computerized tomography showed a diffuse high-density lesion along the left tentorium and falx cerebri. Initial chest X-rays revealed a small mass in the right upper lobe with right lower pleural thickening, which suggested lung cancer, such as an adenoma or mediastinal metastasis. During conservative treatment under the diagnosis of a subdural hematoma, left cranial nerve palsies were developed (3rd and 6th), followed by scleritis and uveitis involving both eyes. Magnetic resonance imaging (MRI) revealed an unusual tentorium-falx enhancement on gadolinium-enhanced T1-weighted images. Non-specific chronic inflammation of the pachymeninges was noticed on histopathologic examination following an open biopsy. Systemic steroid treatment was initiated, resulting in dramatic improvement of symptoms. A follow-up brain MRI showed total resolution of the lesion 2 months after steroid treatment. IHCP should be included in the differential diagnosis of subtentorial-enhancing lesions. PMID:20856672

  15. Current concepts related to hypertrophic scarring in burn injuries.

    PubMed

    Chiang, Ryan S; Borovikova, Anna A; King, Kassandra; Banyard, Derek A; Lalezari, Shadi; Toranto, Jason D; Paydar, Keyianoosh Z; Wirth, Garrett A; Evans, Gregory R D; Widgerow, Alan D

    2016-05-01

    Scarring following burn injury and its accompanying aesthetic and functional sequelae still pose major challenges. Hypertrophic scarring (HTS) can greatly impact patients' quality of life related to appearance, pain, pruritus and even loss of function of the injured body region. The identification of molecular events occurring in the evolution of the burn scar has increased our knowledge; however, this information has not yet translated into effective treatment modalities. Although many of the pathophysiologic pathways that bring about exaggerated scarring have been identified, certain nuances in burn scar formation are starting to be recognized. These include the effects of neurogenic inflammation, mechanotransduction, and the unique interactions of burn wound fluid with fat tissue in the deeper dermal layers, all of which may influence scarring outcome. Tension on the healing scar, pruritus, and pain all induce signaling pathways that ultimately result in increased collagen formation and myofibroblast phenotypic changes. Exposure of the fat domes in the deep dermis is associated with increased HTS, possibly on the basis of altered interaction of adipose-derived stem cells and the deep burn exudate. These pathophysiologic patterns related to stem cell-cytokine interactions, mechanotransduction, and neurogenic inflammation can provide new avenues of exploration for possible therapeutic interventions. PMID:27027596

  16. What Do Patients With Hypertrophic Cardiomyopathy Die from?

    PubMed

    Maron, Barry J; Rowin, Ethan J; Casey, Susan A; Garberich, Ross F; Maron, Martin S

    2016-02-01

    Hypertrophic cardiomyopathy (HC) has become a contemporary and treatable genetic heart disease, now with disease-related mortality reduced to as low as 0.5% per year, based largely on more effective risk stratification and the use of the implantable cardioverter-defibrillator for primary prevention of sudden death. This paradigm change in the natural history of HC has caused us to reconsider the overall mortality risk in this disease. We interrogated the databases of 2 HC referral centers, Minneapolis Heart Institute and Tufts Medical Center. Of 1,902 consecutive patients evaluated between 1992 and 2013, 1,653 patients (87%) have survived to the end of follow-up and 249 patients (13%) have died. Most deaths (178 of 249; 72%) were unrelated to HC, commonly because of cancer and predominantly in older patients. Non-HC mortality was significantly more common in adults presenting ≥ 60 years and least common in the youngest patients aged <30 years (p <0.001). Notably, deaths from non-HC causes substantially exceeded HC-related causes by 2.6-fold (p <0.001). In conclusion, only about 25% of patients with HC ultimately died of their disease, including predominantly those who were <30 years of age. These data allow patients with HC to develop a more realistic and reassured perception of their disease. PMID:26718233

  17. Private Mitochondrial DNA Variants in Danish Patients with Hypertrophic Cardiomyopathy

    PubMed Central

    Hagen, Christian M.; Aidt, Frederik H.; Havndrup, Ole; Hedley, Paula L.; Jensen, Morten K.; Kanters, Jørgen K.; Pham, Tam T.; Bundgaard, Henning; Christiansen, Michael

    2015-01-01

    Hypertrophic cardiomyopathy (HCM) is a genetic cardiac disease primarily caused by mutations in genes coding for sarcomeric proteins. A molecular-genetic etiology can be established in ~60% of cases. Evolutionarily conserved mitochondrial DNA (mtDNA) haplogroups are susceptibility factors for HCM. Several polymorphic mtDNA variants are associated with a variety of late-onset degenerative diseases and affect mitochondrial function. We examined the role of private, non-haplogroup associated, mitochondrial variants in the etiology of HCM. In 87 Danish HCM patients, full mtDNA sequencing revealed 446 variants. After elimination of 312 (69.9%) non-coding and synonymous variants, a further 109 (24.4%) with a global prevalence > 0.1%, three (0.7%) haplogroup associated and 19 (2.0%) variants with a low predicted in silico likelihood of pathogenicity, three variants: MT-TC: m.5772G>A, MT-TF: m.644A>G, and MT-CYB: m.15024G>A, p.C93Y remained. A detailed analysis of these variants indicated that none of them are likely to cause HCM. In conclusion, private mtDNA mutations are frequent, but they are rarely, if ever, associated with HCM. PMID:25923817

  18. Comprehensive Versus Targeted Genetic Testing in Children with Hypertrophic Cardiomyopathy.

    PubMed

    Bales, Nathan D; Johnson, Nicole M; Judge, Daniel P; Murphy, Anne M

    2016-06-01

    Hypertrophic cardiomyopathy (HCM) is a genetic disease of the sarcomere that can be found in both children and adults and is associated with many causative mutations. In children who are not the index case of HCM in their families, current recommendations call only for targeted genetic testing for familial mutations. However, clinical experience suggests that de novo mutations are possible, as are mutations inherited from apparently an unaffected parent. A chart review was conducted of all patients who received HCM genetic testing at Johns Hopkins from 2004 to 2013. In total, 239 patient charts were analyzed for personal and familial genetic findings. Eighty-one patients with sarcomere gene mutations were identified, of which 66 had a clinical diagnosis of HCM. Importantly, eight patients had >1 pathogenic or likely pathogenic mutation, including six patients who were diagnosed with HCM as children (18 or younger). In this analysis, when a sarcomere mutation is identified in a family, the likelihood of a child with HCM having >1 mutation is 25 % (6/24), compared to 4.8 % (2/42) for adults. The large number of children with multiple mutations suggests that broad panel rather than targeted genetic testing should be considered in HCM presenting during childhood even if the child is not the index case. PMID:26936621

  19. Echocardiographic diagnosis of the different phenotypes of hypertrophic cardiomyopathy.

    PubMed

    Parato, Vito Maurizio; Antoncecchi, Valeria; Sozzi, Fabiola; Marazia, Stefania; Zito, Annapaola; Maiello, Maria; Palmiero, Pasquale

    2016-01-01

    Hypertrophic Cardiomyopathy (HCM) is an inherited cardiovascular disorder of great genetic heterogeneity and has a prevalence of 0.1 - 0.2 % in the general population. Several hundred mutations in more than 27 genes, most of which encode sarcomeric structures, are associated with the HCM phenotype. Then, HCM is an extremely heterogeneous disease and several phenotypes have been described over the years. Originally only two phenotypes were considered, a more common, obstructive type (HOCM, 70 %) and a less common, non-obstructive type (HNCM, 30 %) (Maron BJ, et al. Am J Cardiol 48:418 -28, 1981). Wigle et al. (Circ 92:1680-92, 1995) considered three types of functional phenotypes: subaortic obstruction, midventricular obstruction and cavity obliteration. A leader american working group suggested that HCM should be defined genetically and not morphologically (Maron BJ, et al. Circ 113:1807-16, 2006). The European Society of Cardiology Working Group on Myocardial and Pericardial Diseases recommended otherwise a morphological classification (Elliott P, et al. Eur Heart J 29:270-6, 2008). Echocardiography is still the principal tool for the diagnosis, prognosis and clinical management of HCM. It is well known that the echocardiographic picture may have a clinical and prognostic impact. For this reason, in this article, we summarize the state of the art regarding the echocardiographic pattern of the HCM phenotypes and its impact on clinical course and prognosis. PMID:27519172

  20. Diastolic filling in a physical model of obstructive hypertrophic cardiomyopathy

    NASA Astrophysics Data System (ADS)

    Schovanec, Joseph; Samaee, Milad; Lai, Hong Kuan; Santhanakrishnan, Arvind

    2015-11-01

    Hypertrophic Cardiomyopathy (HCM) is an inherited heart disease that affects as much as one in 500 individuals, and is the most common cause of sudden death in young athletes. The myocardium becomes abnormally thick in HCM and deforms the internal geometry of the left ventricle (LV). Previous studies have shown that a vortex is formed during diastolic filling, and further that the dilated LV morphology seen in systolic heart failure results in altering the filling vortex from elliptical to spherical shape. We have also previously shown that increasing LV wall stiffness decreases the filling vortex circulation. However, alterations to intraventricular filling fluid dynamics due to an obstructive LV morphology and locally elevated wall stiffness (in the hypertrophied region) have not been previously examined from a mechanistic standpoint. We conducted an experimental study using an idealized HCM physical model and compared the intraventricular flow fields obtained from 2D PIV to a baseline LV physical model with lower wall stiffness and anatomical geometry. The obstruction in the HCM model leads to earlier breakdown of the filling vortex as compared to the anatomical LV. Intraventricular filling in both models under increased heart rates will be discussed.

  1. Idiopathic hypertrophic pachymeningitis mimicking prolactinoma with recurrent vision loss.

    PubMed

    Lok, Julie Y C; Yip, Nelson K F; Chong, Kelvin K L; Li, C L; Young, Alvin L

    2015-08-01

    Idiopathic hypertrophic pachymeningitis is a rare inflammatory condition with diffuse thickening of the dura mater, which may cause a compressive effect or vascular compromise. We report on a 28-year-old Chinese woman with a history of granulomatous mastitis 7 years previously and oligomenorrhoea, headache, blurred vision, and raised prolactin level 2 years previously, that was diagnosed as prolactinoma and treated conservatively with bromocriptine. However, she had recurrent bilateral vision loss when the bromocriptine was stopped. Her symptoms were resolved by high-dose steroid injection but remained steroid-dependent. Serial magnetic resonance imaging scan showed progressive diffuse thickening of the pachymeningitis with disappearance of pituitary apoplexy. Lumbar puncture showed lymphocytosis with no organisms. Open biopsy of the meninges was performed and histology showed features of inflammatory infiltrates and vasculitis. This is an unusual presentation of a rare condition in this age-group, with co-existing granulomatous mastitis and chronic otitis media, and is a diagnostic challenge mimicking pituitary macroadenoma and meningioma in initial magnetic resonance imaging scans. PMID:26238133

  2. Distinguishing ventricular septal bulge versus hypertrophic cardiomyopathy in the elderly.

    PubMed

    Canepa, Marco; Pozios, Iraklis; Vianello, Pier Filippo; Ameri, Pietro; Brunelli, Claudio; Ferrucci, Luigi; Abraham, Theodore P

    2016-07-15

    The burgeoning evidence of patients diagnosed with sigmoidal hypertrophic cardiomyopathy (HCM) later in life has revived the quest for distinctive features that may help discriminate it from more benign forms of isolated septal hypertrophy often labelled ventricular septal bulge (VSB). HCM is diagnosed less frequently than VSB at older ages, with a reversed female predominance. Most patients diagnosed with HCM at older ages suffer from hypertension, similar to those with VSB. A positive family history of HCM and/or sudden cardiac death and the presence of exertional symptoms usually support HCM, though they are less likely in older patients with HCM, and poorly investigated in individuals with VSB. A more severe hypertrophy and the presence of left ventricular outflow obstruction are considered diagnostic of HCM, though stress echocardiography has not been consistently used in VSB. Mitral annulus calcification is very prevalent in both conditions, whereas a restrictive filling pattern is found in a minority of older patients with HCM. Genetic testing has low applicability in this differential diagnosis at the current time, given that a causative mutation is found in less than 10% of elderly patients with suspected HCM. Emerging imaging modalities that allow non-invasive detection of myocardial fibrosis and disarray may help, but have not been fully investigated. Nonetheless, there remains a considerable morphological overlap between the two conditions. Comprehensive studies, particularly imaging based, are warranted to offer a more evidence-based approach to elderly patients with focal septal thickening. PMID:27122487

  3. Magnetic flux concentrations from turbulent stratified convection

    NASA Astrophysics Data System (ADS)

    Käpylä, P. J.; Brandenburg, A.; Kleeorin, N.; Käpylä, M. J.; Rogachevskii, I.

    2016-04-01

    Context. The formation of magnetic flux concentrations within the solar convection zone leading to sunspot formation is unexplained. Aims: We study the self-organization of initially uniform sub-equipartition magnetic fields by highly stratified turbulent convection. Methods: We perform simulations of magnetoconvection in Cartesian domains representing the uppermost 8.5-24 Mm of the solar convection zone with the horizontal size of the domain varying between 34 and 96 Mm. The density contrast in the 24 Mm deep models is more than 3 × 103 or eight density scale heights, corresponding to a little over 12 pressure scale heights. We impose either a vertical or a horizontal uniform magnetic field in a convection-driven turbulent flow in set-ups where no small-scale dynamos are present. In the most highly stratified cases we employ the reduced sound speed method to relax the time step constraint arising from the high sound speed in the deep layers. We model radiation via the diffusion approximation and neglect detailed radiative transfer in order to concentrate on purely magnetohydrodynamic effects. Results: We find that super-equipartition magnetic flux concentrations are formed near the surface in cases with moderate and high density stratification, corresponding to domain depths of 12.5 and 24 Mm. The size of the concentrations increases as the box size increases and the largest structures (20 Mm horizontally near the surface) are obtained in the models that are 24 Mm deep. The field strength in the concentrations is in the range of 3-5 kG, almost independent of the magnitude of the imposed field. The amplitude of the concentrations grows approximately linearly in time. The effective magnetic pressure measured in the simulations is positive near the surface and negative in the bulk of the convection zone. Its derivative with respect to the mean magnetic field, however, is positive in most of the domain, which is unfavourable for the operation of the negative

  4. Enteric neuronal plasticity and a reduced number of interstitial cells of Cajal in hypertrophic rat ileum

    PubMed Central

    Ekblad, E; Sjuve, R; Arner, A; Sundler, F

    1998-01-01

    Background—Partial obstruction of the ileum causes a notable hypertrophy of smooth muscle cells and enteric neurones in the proximally located intestine. 
Aims—To study the expression of neuromessengers in the hypertrophic ileum of rat as little is known about neuromessenger plasticity under these conditions. To investigate the presence of interstitial cells of Cajal (ICC) in hypertrophic ileum. 
Methods—Ileal hypertrophy was induced by circumferential application of a strip of plastic film for 18-24 days. Immunocytochemistry, in situ hybridisation, nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase histochemistry, and ethidium bromide staining were used to investigate the number of enteric neurones expressing neuropeptides and nitric oxide synthase, and the frequency of ICC. 
Results—In the hypertrophic ileum several neuronal populations showed changes in their expression of neuromessengers. Myenteric neurones expressing vasoactive intestinal peptide (VIP), pituitary adenylate cyclase activating peptide, and galanin were notably increased in number. In submucous ganglia the number of VIP immunoreactive neurones decreased while those expressing VIP mRNA increased. NADPH diaphorase positive submucous neurones increased dramatically while the number of neuronal type nitric oxide synthase expressing ones was unchanged. The number of ICC decreased notably in hypertrophic ileum. 
Conclusion—Enteric neurones change their levels of expression of neuromessengers in hypertrophic ileum. ICC are also affected. The changes are presumably part of an adaptive response to the increased work load. 

 Keywords: enteric nerves; interstitial cells of Cajal; hypertrophy; neuropeptides; nitric oxide; neuronal plasticity PMID:9691923

  5. Curative Effects of Oleanolic Acid on Formed Hypertrophic Scars in the Rabbit Ear Model

    PubMed Central

    Zhang, Hong; Zhang, Yan; Jiang, Yi-Ping; Zhang, Lan-Ke; Peng, Cheng; He, Kun; Rahman, Khalid; Qin, Lu-Ping

    2012-01-01

    Hypertrophic scarring is a common proliferative disorder of dermal fibroblasts characterized by collagen overproduction and excessive deposition of extracellular matrix (ECM). There is no consensus about the best therapeutics to produce complete and permanent improvement of scars with few side effects. To investigate the therapeutic effects of oleanolic acid (OA) on hypertrophic scars and explore the possible mechanism of action involved, a rabbit ear model with hypertrophic scars was established. OA (2.5%, 5%, and 10%) was given once daily to the scars for 28 consecutive days. As a result, OA significantly alleviated formed hypertrophic scars on rabbit ears. The levels of TGF-β1, MMP-1, TIMP-1, and collagens I and III were notably decreased, and the number of apoptosis cells and mRNA expression of MMP-2, caspase-3, and caspase-9 were markedly increased in the scar tissue. The scar elevation index (SEI) was also evidently reduced. Histological findings exhibited significant amelioration of the collagen tissue. These results suggest that OA has the favorable curative effects on formed hypertrophic scars in the rabbit ear model, and the possible mechanism of action is that OA decreases HSFs proliferation and increases HSFs apoptosis by reduction of P311 gene expression and TGF-β1 production, inhibition of TIMP-1 secretion, enhancement of MMP-2 activity, and subsequently facilitation of degradation of collagen types I and III. PMID:23326292

  6. 3-D Eutrophication Modeling for Lake Simcoe, Canada

    NASA Astrophysics Data System (ADS)

    Lu, Q.; Duckett, F.; Nairn, R.; Brunton, A.

    2006-12-01

    The Lake Simcoe Region Conservation Authority (LSRCA) and the Province of Ontario are undertaking a series of studies to facilitate management of the pressures of population growth in the Lake Simcoe watershed. With rapid population growth and urban development comes additional land clearing, storm water runoff and the discharge of treated sewage, all of which are sources of increased phosphorus loading to Lake Simcoe. Depressed oxygen levels were linked to phosphorous enrichment of the lake, with the resultant stimulation of algal growth in the sunlit upper waters of the lake, and its subsequent senescence and settling into the hypolimnion where bacterial decomposition consumes oxygen from the stratified waters. This poster describes a 3-D hydrodynamic, thermal and water quality model of Lake Simcoe developed using the Danish Hydraulics Institute (DHI) MIKE3 model. The hydrodynamic module includes wind-driven circulation, temperature variation, development of the thermocline and thermal stratification, and hydraulic forcing from inflowing tributaries. This is linked to the water quality module which simulates the eutrophication processes in the response of the lake to loadings of phosphorus, such as algal growth, the growth of aquatic plants and subsequent oxygen consumption. The model has been calibrated against Acoustic Doppler Current Profiler velocity data, plus measured temperature and water quality data at MOE stations in the lake and water intakes. The model is an important assessment tool for the management of the lake and its watersheds, allowing assessment of the impacts of the urban growth and land use change on the water quality in Lake Simcoe.

  7. STRATIFIED COMPOSITION EFFECTS ON PLANETARY NEUTRON FLUX

    SciTech Connect

    O. GASNAULT; ET AL

    2001-01-01

    All the bodies of the solar system that are directly irradiated by the galactic cosmic rays, emit enough neutrons to allow a measurement from space. These leakage neutron fluxes are indexes of the surface composition, depending on the energy of the neutrons [1]. Recent work propose geochemical interpretations of these fluxes: the thermal energy range is sensitive to iron, titanium, rare earth elements and thorium [2, 3], the epithermal energy range is sensitive to hydrogen, samarium and gadolinium [2] and the fast energy range is representative of the average soil atomic mass [4]. Nevertheless these studies make the hypothesis of a composition uniform within the footprint of the spectrometer and independent of depth. We show in this abstract that a stratified composition could change significantly the flux intensity and complicate the interpretation of the measurements. The neutron leakage flux is a competition between production effects (sensitive at high energy) and diffusion-capture effects (mostly sensitive at low energy). On one hand, it happens to be that the elements which produce the higher number of neutrons in typical lunar compositions are iron and titanium, which have also large cross section of absorption with the neutrons. On the other hand, the maximum of neutron intensity does not occur at the surface but at about 180 g cm{sup {minus}2} in depth. Therefore, if we have an iron- and/or titanium-rich soil (important production of neutrons) with a top layer having less iron and/or titanium (i.e. more transparent to the neutrons), we can expect an enhancement of the flux compared to a uniform composition.

  8. Seasonal habitat selection by lake trout (Salvelinus namaycush) in a small Canadian shield lake: Constraints imposed by winter conditions

    USGS Publications Warehouse

    Blanchfield, P.J.; Tate, L.S.; Plumb, J.M.; Acolas, M.-L.; Beaty, K.G.

    2009-01-01

    The need for cold, well-oxygenated waters significantly reduces the habitat available for lake trout (Salvelinus namaycush) during stratification of small temperate lakes. We examined the spatial and pelagic distribution of lake trout over two consecutive summers and winters and tested whether winter increased habitat availability and access to littoral regions in a boreal shield lake in which pelagic prey fish are absent. In winter, lake trout had a narrowly defined pelagic distribution that was skewed to the upper 3 m of the water column and spatially situated in the central region of the lake. Individual core areas of use (50% Kernel utilization distributions) in winter were much reduced (75%) and spatially non-overlapping compared to summer areas, but activity levels were similar between seasons. Winter habitat selection is in contrast to observations from the stratified season, when lake trout were consistently located in much deeper waters (>6 m) and widely distributed throughout the lake. Winter distribution of lake trout appeared to be strongly influenced by ambient light levels; snow depth and day length accounted for up to 69% of the variation in daily median fish depth. More restricted habitat use during winter than summer was in contrast to our original prediction and illustrates that a different suite of factors influence lake trout distribution between these seasons. ?? Springer Science+Business Media B.V. 2009.

  9. An Atypical Case of Apical Hypertrophic Cardiomyopathy: Absence of Giant T Waves in spite of Extreme Apical Wall Hypertrophy.

    PubMed

    Sanidas, Elias; Bonou, Maria; Anastasiadis, Georgios; Tzanis, Georgios; Barbetseas, John

    2015-01-01

    Apical hypertrophic cardiomyopathy is an uncommon variant of hypertrophic cardiomyopathy, with hypertrophy mainly affecting the apex of the left ventricle. We hereby describe a case of an octogenarian female patient who was randomly diagnosed with AHCM due to other comorbidities. PMID:26779351

  10. An Atypical Case of Apical Hypertrophic Cardiomyopathy: Absence of Giant T Waves in spite of Extreme Apical Wall Hypertrophy

    PubMed Central

    Sanidas, Elias; Bonou, Maria; Anastasiadis, Georgios; Tzanis, Georgios; Barbetseas, John

    2015-01-01

    Apical hypertrophic cardiomyopathy is an uncommon variant of hypertrophic cardiomyopathy, with hypertrophy mainly affecting the apex of the left ventricle. We hereby describe a case of an octogenarian female patient who was randomly diagnosed with AHCM due to other comorbidities. PMID:26779351

  11. Bimodal spectroscopy for in vivo characterization of hypertrophic skin tissue : pre-clinical experimentation, data selection and classification.

    PubMed

    Liu, H; Gisquet, H; Blondel, W; Guillemin, F

    2012-12-01

    This study aims at investigating the efficiency of bimodal spectroscopy in detection of hypertrophic scar tissue on a preclinical model. Fluorescence and Diffuse Reflectance spectra were collected from 55 scars deliberately created on ears of 20 rabbits, amongst which some received tacrolimus injection to provide non-hypertrophic scar tissue. The spectroscopic data measured on hypertrophic and non-hypertrophic scar tissues were used for developing our classification algorithm. Spectral features were extracted from corrected data and analyzed to classify the scar tissues into hypertrophic or non-hypertrophic. The Algorithm was developed using k-NN classifier and validated by comparing to histological classification result with Leave-One-Out cross validation. Bimodal spectroscopy showed promising results in detecting hypertrophic tissue (sensibility 90.5%, specificity 94.4%). The features used for classification were extracted from the autofluorescence spectra collected at 4 CEFS with excitations at 360, 410, and 420 nm. This indicates the hypertrophic process may involve change in concentration of several fluorophores (collagen, elastin and NADH) excited in this range, or modification in volume of explored tissue layers (epidermis and dermis) due to tissue thickening. PMID:23243577

  12. Effect of Drag Reducing Polymers on Stratified and Stratified/Annular Flow in a Horizontal Duct

    NASA Astrophysics Data System (ADS)

    Pernica, Patricia; Fleck, Brian; Heidrick, Ted

    2006-11-01

    An investigation was carried out to determine the effects of a drag reducing additive (DRA) on two phase flow in horizontal stratified and stratified/annular flow patterns. Experiments were conducted in an air-water flow in a transparent rectangular channel of cross-section 25.4 mm x 50.8 mm and 2.5 m in length. Pressure drop measurements, wave characteristics and observations of entrainment with and without DRA are presented. A non-contact measurement technique using laser induced fluorescence and high speed videography was used to measure span-wise liquid wave heights and to characterize the air-water interface. Pressure drop was measured at the centerline of the duct over a one meter distance. The onset of entrainment was observed visually. Effects of DRA were observed even at a low concentration of 5ppm. This concentration yielded pressure drop reductions of 10-15% which correlate with previous experiments done in horizontal pipelines. Observations also show dampening of roll waves and the suppression of atomization. Al-Sarkhi, A., Hanratty, T.J., Int J. Multiphase Flow, 27, 1151 (2001)

  13. The presence of lysylpyridinoline in the hypertrophic cartilage of newly hatched chicks

    NASA Technical Reports Server (NTRS)

    Orth, M. W.; Martinez, D. A.; Cook, M. E.; Vailas, A. C.

    1993-01-01

    The presence of lysylpyridinoline (LP) as a nonreducible cross-link in appreciable quantities has primarily been limited to the mineralized tissues, bone and dentin. However, the results reported here show that LP is not only present in the hypertrophic cartilage of the tibiotarsus isolated from newly hatched broiler chicks, but it is approx. 4-fold as concentrated as hydroxylysylpyridinoline (HP). Bone and articular cartilage surrounding the hypertrophic cartilage do not contain measurable quantities of LP. Purified LP has a fluorescent scan similar to purified HP and literature values, confirming that we indeed were measuring LP. Also, the cartilage lesion produced by immature chondrocytes from birds with tibial dyschondroplasia had LP but the HP:LP ratio was > 1. Thus, the low HP:LP ratio could be a marker for hypertrophic cartilage in avians.

  14. Using Nuclear Receptor Activity to Stratify Hepatocarcinogens

    PubMed Central

    Shah, Imran; Houck, Keith; Judson, Richard S.; Kavlock, Robert J.; Martin, Matthew T.; Reif, David M.; Wambaugh, John; Dix, David J.

    2011-01-01

    utility of in vitro assays for stratifying environmental contaminants based on a combination of human bioactivity and rodent toxicity. PMID:21339822

  15. Gas slug ascent through rheologically stratified conduits

    NASA Astrophysics Data System (ADS)

    Capponi, Antonio; James, Mike R.; Lane, Steve J.

    2016-04-01

    Textural and petrological evidence has indicated the presence of viscous, degassed magma layers at the top of the conduit at Stromboli. This layer acts as a plug through which gas slugs burst and it is thought to have a role in controlling the eruptive dynamics. Here, we present the results of laboratory experiments which detail the range of slug flow configurations that can develop in a rheologically stratified conduit. A gas slug can burst (1) after being fully accommodated within the plug volume, (2) whilst its base is still in the underlying low-viscosity liquid or (3) within a low-viscosity layer dynamically emplaced above the plug during the slug ascent. We illustrate the relevance of the same flow configurations at volcanic-scale through a new experimentally-validated 1D model and 3D computational fluid dynamic simulations. Applied to Stromboli, our results show that gas volume, plug thickness, plug viscosity and conduit radius control the transition between each configuration; in contrast, the configuration distribution seems insensitive to the viscosity of magma beneath the plug, which acts mainly to deliver the slug into the plug. Each identified flow configuration encompasses a variety of processes including dynamic narrowing and widening of the conduit, generation of instabilities along the falling liquid film, transient blockages of the slug path and slug break-up. All these complexities, in turn, lead to variations in the slug overpressure, mirrored by changes in infrasonic signatures which are also associated to different eruptive styles. Acoustic amplitudes are strongly dependent on the flow configuration in which the slugs burst, with both acoustic peak amplitudes and waveform shapes reflecting different burst dynamics. When compared to infrasonic signals from Stromboli, the similarity between real signals and laboratory waveforms suggests that the burst of a slug through a plug may represent a viable first-order mechanism for the generation of

  16. Waves and vortices in rotating stratified turbulence

    NASA Astrophysics Data System (ADS)

    Pouquet, Annick; Herbert, Corentin; Marino, Raffaele; Rosenberg, Duane

    2015-04-01

    The interactions between vortices and waves is a long-standing problem in fluid turbulence. It can lead to a self-sustaining process that is dominant, for example in pipe flows, and to the prediction of large-scale coherent structures such as baroclinic jets in planetary atmospheres, and it can also be used as a control tool for the onset of turbulence. Similarly, the dynamics of the atmosphere and the ocean is dominated by complex interactions between nonlinear eddies and waves due to a combination of rotation and stratification (characterized respectively by frequencies f and N), as well as shear layers. The waves are faster at large scales, and this leads to a quasi-geostrophic quasi-linear regime in which there is a balance between pressure gradient and the Coriolis and gravity forces. The range of scales in these geophysical flows before dissipation prevails is such that other regimes can arise in which turbulence comes into play, with the eddy turn-over time becoming comparable to the wave period, and for which isotropy recovers for sufficiently high Reynolds numbers. One may decompose the flow-- observational, experimental or numerical, in terms of the normal modes that it supports, i.e. the inertia-gravity waves and the (slow, zero frequency) vortical modes carrying the potential vorticity, thanks to the existence of a small parameter, as for example the fluctuation around a mean flow or the ratio of the wave period to the eddy turn-over time. In this context an ensemble of data sets of rotating stratified turbulence will be analyzed, stemming from accurate direct numerical simulations of the Boussinesq equations at high resolution, up to 40963 grid points, using high-performance computing. These flows all support a constant-flux bi-directional cascade of energy towards both the large scales and the small scales. The parameter space includes the Reynolds number, the Prandtl number(s), and the Rossby and Froude numbers, and a universal response to a variety

  17. Pak1 as a Novel Therapeutic Target for Anti-Hypertrophic Treatment in the Heart

    PubMed Central

    Liu, Wei; Zi, Min; Naumann, Ronald; Ulm, Susanne; Jin, Jiawei; Taglieri, Domenico M.; Prehar, Sukhpal; Gui, Junhong; Tsui, Hoyee; Xiao, Rui-Ping; Neyses, Ludwig; Solaro, R. John; Ke, Yunbo; Cartwright, Elizabeth J.; Lei, Ming; Wang, Xin

    2011-01-01

    Background Stress-induced hypertrophic remodeling is a critical pathogenetic process leading to heart failure. While many signal transduction cascades are demonstrated as important regulators to facilitate the induction of cardiac hypertrophy, the signaling pathways for suppressing hypertrophic remodeling remain largely unexplored. In this study, we identified p21-activated kinase 1 (Pak1) as a novel signaling regulator which antagonizes cardiac hypertrophy. Methods and Results Hypertrophic stress applied to primary neonatal rat cardiomyocytes (NRCMs), or murine hearts caused the activation of Pak1. Analysis of NRCMs expressing constitutively active Pak1 or in which Pak1 was silenced disclosed that Pak1 played an anti-hypertrophic role. To investigate the in vivo role of Pak1 in the heart, we generated mice with a cardiomyocyte-specific deletion of Pak1 (Pak1cko). When subject to 2 weeks of pressure overload, Pak1cko mice compared to controls, developed greater cardiac hypertrophy with attendant blunting of JNK activation, and these knockout mice underwent the transition into heart failure when prolonged stress was applied. In addition, chronic angiotensin II infusion also caused increased cardiac hypertrophy in Pak1cko mice. Moreover, we discovered that the Pak1 activator FTY720, a sphingosine-like analogue, was able to prevent pressure overload-induced hypertrophy in wild-type mice, without compromising their cardiac functions. Meanwhile FTY720 failed to exert such an effect on Pak1cko mice, suggesting that the anti-hypertrophic effect of FTY720 likely acts through Pak1 activation. Conclusions These results, for the first time, establish Pak1 as a novel anti-hypertrophic regulator and suggest that it may be a potential therapeutic target for the treatment of cardiac hypertrophy and heart failure. PMID:22082674

  18. Effect of lipopolysaccharide on the biological characteristics of human skin fibroblasts and hypertrophic scar tissue formation.

    PubMed

    Yang, Hongming; Hu, Chao; Li, Fengyu; Liang, Liming; Liu, Lingying

    2013-06-01

    Burn injury-mediated destruction of the skin barrier normally induces microbial invasion, in turn leading to the development of systemic infection and occasional septic shock by the release of endotoxins. The objective of this work was to study the influence of lipopolysaccharide (LPS) on the biological characteristics of normal skin fibroblasts and to elucidate the influence of LPS in the initial stage of skin wound healing. Twenty patients with hypertrophic scar in proliferative stage were selected randomly and primary cultures were established from fibroblasts derived from their hypertrophic scar tissue and normal skin. Normal skin fibroblasts of passage 3 were stimulated with different concentrations of LPS. LPS stimulated the proliferation and collagen synthesis of fibroblasts within a certain extent of concentrations (0.005-0.5 μg/mL) (P < 0.05), whereas at a concentration of 1 μg/mL inhibited the proliferation and collagen synthesis of fibroblasts (P < 0.05). Collagen synthesis by normal skin fibroblasts after LPS stimulation mimicked those derived from hypertrophic scar tissue. LPS of 0.1 μg/mL had significant effect on normal skin fibroblasts-continuous passage of these fibroblasts resulted in ultrastructural pattern similar to fibroblasts derived from hypertrophic scar tissue, and the findings was substantiated by hematoxylin and eosin staining and immunohistochemistry detection of proliferation cell nuclear antigen, type I procollagen and α-smooth muscle actin. Our results suggest that LPS might convert normal skin fibroblasts to hypertrophic scar tissue fibroblasts and participate in the formation of hypertrophic scar; hence, appropriate concentration of LPS may have no effect or be beneficial to skin wound healing, whereas excessive concentration of LPS may delay the time of wound healing. PMID:23653386

  19. Clinical significance of giant negative T waves in hypertrophic cardiomyopathy

    SciTech Connect

    Alfonso, F.; Nihoyannopoulos, P.; Stewart, J.; Dickie, S.; Lemery, R.; McKenna, W.J. )

    1990-04-01

    To assess the clinical significance of giant negative T waves in patients with hypertrophic cardiomyopathy from Western nations, clinical, echocardiographic, radionuclide and 48 h electrocardiographic (ECG) monitoring findings were compared in 27 patients with and 56 patients without giant negative T waves. Patients with giant negative T waves were older at diagnosis (43 +/- 15 versus 32 +/- 14 years, p less than 0.005), had greater ECG voltage (SV1 + RV5 = 57 +/- 20 versus 37 +/- 18 mm, p less than 0.001) and had a more vertical frontal plane axis (38.4 +/- 34 versus 13.4 +/- 45 degrees, p less than 0.05). Left ventricular wall thickness on two-dimensional echocardiography was similar at the mitral valve level (mean 16.5 +/- 4 versus 16.6 +/- 3 cm), but was greater at the papillary muscle level (mean 20.7 +/- 5 versus 17.6 +/- 3 mm, p less than 0.01) and apex (mean 23.3 +/- 5 versus 17.3 +/- 3 mm, p less than 0.001) in patients with giant negative T waves. Fewer patients with giant negative T waves had asymmetric septal hypertrophy (12 (44%) of 27 versus 36 (64%) of 56, p = 0.08) or systolic anterior motion of the mitral valve (4 (14%) of 27 versus 25 (45%) of 56, p less than 0.01), whereas left ventricular end-diastolic (44.1 +/- 6 versus 39.6 +/- 5 mm, p = 0.01) and end-systolic dimensions (27.8 +/- 4 versus 24 +/- 6 mm, p less than 0.05) were greater in this group. Nonsustained ventricular tachycardia was seen on ECG monitoring in 21% of patients in both groups.

  20. Operation for hypertrophic subaortic stenosis in the aged.

    PubMed

    Cooper, M M; McIntosh, C L; Tucker, E; Clark, R E

    1987-10-01

    To determine if operative palliation of idiopathic hypertrophic subaortic stenosis (IHSS) is worthwhile in the elderly, hemodynamic, cardiac conduction, symptomatological, functional, and survival data were examined in 52 patients (39 women) 65 years old and older (mean age, 69 years; range, 65 to 81 years) who had a left ventricular myotomy and myectomy (LVMM) (Morrow procedure) alone or with concomitant operations. Seventy-four percent of all operative survivors underwent catheterization an average of 6 months postoperatively. The mean follow-up was 54 months (range, 5 to 120 months). The population was divided for analyses into those with coronary artery disease (CAD) (N = 11,21%) and those without (N = 41). The peak resting left ventricular outflow tract gradient was reduced from 65 +/- 16 mm Hg to 3 +/- 1 mm Hg (p less than 0.01) in the group with CAD and from 95 +/- 13 mm Hg to 17 +/- 9 mm Hg (p less than 0.001) in the group without CAD. Significant reductions in peak gradients in response to provocation also occurred in both groups. New conduction abnormalities occurred in 72% of survivors, 85% of whom showed improvement in regard to symptoms. The overall average New York Heart Association Functional Class was 3.2 +/- 0.1 preoperatively and at latest follow-up, 1.9 +/- 0.1 (p less than 0.001). The hospital mortality for LVMM alone in the absence of CAD was 8% with a 5-year actuarial survival of 75 +/- 8%. LVMM in the presence of CAD resulted in an operative mortality of 27% (N = 3); all deaths were related to an acquired ventricular septal defect.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3662685

  1. Quantitative measurement of hypertrophic scar: interrater reliability and concurrent validity.

    PubMed

    Nedelec, Bernadette; Correa, José A; Rachelska, Grazyna; Armour, Alexis; LaSalle, Léo

    2008-01-01

    Research into the pathophysiology and treatment of hypertrophic scar (HSc) remains limited by the heterogeneity of scar and the imprecision with which its severity is measured. The objective of this study was to test the interrater reliability and concurrent validity of the Cutometer measurement of elasticity, the Mexameter measurement of erythema and pigmentation, and total thickness measure of the DermaScan C relative to the modified Vancouver Scar Scale (mVSS) in patient-matched normal skin, normal scar, and HSc. Three independent investigators evaluated 128 sites (severe HSc, moderate or mild HSc, donor site, and normal skin) on 32 burn survivors using all of the above measurement tools. The intraclass correlation coefficient, which was used to measure interrater reliability, reflects the inherent amount of error in the measure and is considered acceptable when it is >0.75. Interrater reliability of the totals of the height, pliability, and vascularity subscales of the mVSS fell below the acceptable limit ( congruent with0.50). The individual subscales of the mVSS fell well below the acceptable level (< or =0.3). The Cutometer reading of elasticity provided acceptable reliability (>0.89) for each study site with the exception of severe scar. Mexameter and DermaScan C reliability measurements were acceptable for all sites (>0.82). Concurrent validity correlations with the mVSS were significant except for the comparison of the mVSS pliability subscale and the Cutometer maximum deformation measure comparison in severe scar. In conclusion, the Mexameter and DermaScan C measurements of scar color and thickness of all sites, as well as the Cutometer measurement of elasticity in all but the most severe scars shows high interrater reliability. Their significant concurrent validity with the mVSS confirms that these tools are measuring the same traits as the mVSS, and in a more objective way. PMID:18388576

  2. Hypertrophic Osteoarthropathy and Follicular Thyroid Cancer: A Rare Paraneoplastic Syndrome

    PubMed Central

    Tavarelli, Martina; Sarfati, Julie; De Gennes, Christian; Haroche, Julien; Buffet, Camille; Ghander, Cécile; Simon, Jean Marc; Ménégaux, Fabrice; Leenhardt, Laurence

    2015-01-01

    Background Hypertrophic osteoarthropathy (HOA) is a rare condition characterized by bone and joint pain and digital clubbing usually associated with bronchopulmonary diseases. Primary HOA is rare and the pathogenesis remains unclear. Objectives Cases of HOA as a paraneoplastic syndrome associated with thyroid carcinoma are very rare – only 2 cases have been described in the literature. Results We present the first case of a 40-year-old patient affected by HOA associated with invasive differentiated follicular thyroid carcinoma operated in 2 stages. Both operations were followed by radioiodine ablation, and then a rapid unresectable local recurrence developed requiring cervical radiotherapy (70 Gy). A second treatment with 100 mCi of 131I confirmed it was a refractory thyroid cancer. Further surgery confirmed a poorly differentiated follicular cancer and 12 cycles of chemotherapy by gemcitabine and oxaliplatin followed. During the 8 years of follow-up, cervical recurrence was stable, but severe episodes of hemoptysis occurred requiring iterative embolization of the bronchial and tracheal arteries. Other lung diseases were excluded. Digital clubbing appeared, which was associated with arthritis, bone pain and inflammatory syndrome. X-rays and magnetic resonance imaging found periosteal apposition in the long bones; bone scintigraphy confirmed the HOA diagnosis. Other causes of arthritis were eliminated. She was treated with colchicine, corticosteroids and nonsteroidal anti-inflammatory drugs, but only the combination of methotrexate and hydroxychloroquine reduced the morphine requirements. Conclusion HOA is exceptionally associated with thyroid cancer and we raised the hypothesis of the secretion of a circulating factor in a patient with invasive and recurrent follicular thyroid cancer, refractory to radioiodine. PMID:26835431

  3. Utilizing ECG-Based Heartbeat Classification for Hypertrophic Cardiomyopathy Identification.

    PubMed

    Rahman, Quazi Abidur; Tereshchenko, Larisa G; Kongkatong, Matthew; Abraham, Theodore; Abraham, M Roselle; Shatkay, Hagit

    2015-07-01

    Hypertrophic cardiomyopathy (HCM) is a cardiovascular disease where the heart muscle is partially thickened and blood flow is (potentially fatally) obstructed. A test based on electrocardiograms (ECG) that record the heart electrical activity can help in early detection of HCM patients. This paper presents a cardiovascular-patient classifier we developed to identify HCM patients using standard 10-second, 12-lead ECG signals. Patients are classified as having HCM if the majority of their recorded heartbeats are recognized as characteristic of HCM. Thus, the classifier's underlying task is to recognize individual heartbeats segmented from 12-lead ECG signals as HCM beats, where heartbeats from non-HCM cardiovascular patients are used as controls. We extracted 504 morphological and temporal features—both commonly used and newly-developed ones—from ECG signals for heartbeat classification. To assess classification performance, we trained and tested a random forest classifier and a support vector machine classifier using 5-fold cross validation. We also compared the performance of these two classifiers to that obtained by a logistic regression classifier, and the first two methods performed better than logistic regression. The patient-classification precision of random forests and of support vector machine classifiers is close to 0.85. Recall (sensitivity) and specificity are approximately 0.90. We also conducted feature selection experiments by gradually removing the least informative features; the results show that a relatively small subset of 264 highly informative features can achieve performance measures comparable to those achieved by using the complete set of features. PMID:25915962

  4. Abnormal Mitral Valve Dimensions in Pediatric Patients with Hypertrophic Cardiomyopathy.

    PubMed

    Schantz, Daryl; Benson, Lee; Windram, Jonathan; Wong, Derek; Dragulescu, Andreea; Yoo, Shi-Joon; Mertens, Luc; Friedberg, Mark; Al Nafisi, Bahiyah; Grosse-Wortmann, Lars

    2016-04-01

    The hearts of patients with hypertrophic cardiomyopathy (HCM) show structural abnormalities other than isolated wall thickening. Recently, adult HCM patients have been found to have longer mitral valve leaflets than control subjects. The aim of the current study was to assess whether children and adolescents with HCM have similar measureable differences in mitral valve leaflet dimensions when compared to a healthy control group. Clinical and echocardiographic data from 46 children with myocardial hypertrophy and a phenotype and/or genotype consistent with sarcomeric HCM were reviewed. Cardiac magnetic resonance imaging studies were evaluated. The anterior and posterior mitral valve leaflet lengths and myocardial structure were compared to 20 healthy controls. The anterior mitral valve was longer in the HCM group than in the control group (28.4 ± 4.9 vs. 25.2 ± 3.6 mm in control patients, p = 0.013) as was the posterior mitral valve leaflet (16.3 ± 3.0 vs. 13.1 ± 2.3 mm for controls <0.0001). There was no correlation between the resting left ventricular outflow tract gradient and anterior mitral valve leaflet length, nor was the anterior mitral valve leaflet longer in those with systolic anterior motion of the mitral valve compared to those without (28.9 ± 6.1 vs. 28.1 ± 4.5 mm, p = 0.61). Children and adolescents with HCM have abnormally long mitral valve leaflets when compared with healthy control subjects. These abnormalities do not appear to result in, or be due to, obstruction to left ventricular outflow. The mechanism of this mitral valve elongation is not clear but appears to be independent of hemodynamic disturbances. PMID:26961572

  5. Radiofrequency catheter septal ablation for hypertrophic obstructive cardiomyopathy in children

    PubMed Central

    Emmel, M.; Sreeram, N.

    2005-01-01

    Background The definitive therapeutic options for symptomatic obstructive cardiomyopathy in childhood are restricted. At present, extensive surgical myectomy is the only procedure that is of proven benefit. Patients and Methods Three patients, aged 5, 11 and 17 years, respectively, with progressive hypertrophic obstructive cardiomyopathy and increasing symptoms were considered for radiofrequency catheter septal ablation. The peak Doppler gradient recorded on several occasions ranged between 50 to 90mmHg. Via a femoral arterial approach, the His bundle was initially plotted and marked using the LocaLisa navigation system. Subsequently, using a cooled tip catheter a series of lesions were placed in the hypertrophied septum, taking care to stay away from the His bundle. A total of 17, 50 and 45 lesions were applied in the three patients. In one case, the procedure was complicated by two episodes of ventricular fibrillation requiring DC cardioversion but without any neurological sequelae. Results The preablation peak-to-peak gradient between left ventricle and aorta was 50 mmHg, 60 mmHg and 60 mmHg, respectively, and remained unchanged immediately after the procedure. All patients were discharged from hospital 48 hours later. Serial measurement of serum troponin T and CK-MB isoenzyme confirmed significant myocardial necrosis. Follow-up echocardiography both at seven days and at six weeks postablation confirmed a beneficial haemodynamic result, with reduction of left ventricular outflow obstruction and relief of symptoms. Conclusion In young children, in whom alcohol-induced septal ablation is not an option, radiofrequency catheter ablation offers an alternative to surgery, with the benefits of repeatability and a lower risk of procedure-related permanent AV block. ImagesFigure 1Figure 2Figure 3Figure 4 PMID:25696442

  6. [Regional right ventricular hypertrophy in hypertrophic cardiomyopathy and hypertension].

    PubMed

    Seo, T; Yokota, Y; Kumaki, T; Takarada, A; Kubo, M; Kaku, K; Toh, S; Fukuzaki, H

    1985-06-01

    The mode of right ventricular hypertrophy was assessed by two-dimensional echocardiography (2DE) for 24 patients with hypertrophic cardiomyopathy (HCM), and the results were compared with those of 51 patients with hypertension (HT). The patients with HT were categorized in four groups depending on the thickness of the interventricular septum (IVST) and left ventricular posterior wall (PWT): HT-ASH with both left ventricular hypertrophy (LVH) (IVST greater than or equal to 13 mm) and asymmetric septal hypertrophy (ASH) (IVST/PWT greater than or equal to 1.3), severe HT with LVH and without ASH, and mild HT without LVH and ASH. Anterior wall thickness (AWT), posterior wall thickness (PWT), and diaphragmatic wall thickness (DWT) of the right ventricle were obtained from 2DE in the parasternal long-axis view, the short-axis view and subxiphoid view, respectively. These were recorded on video tape, and the measurements were made on the stop frames. Right ventricular hypertrophy (RVH) was estimated by the maximal right ventricular wall thickness (max RVWT), and the ratio of the maximal and minimal thickness (max RVWT/min RVWT) was calculated to evaluate asymmetrical hypertrophy (AH) of the right ventricle (RV). The incidence of RVH (Max RVWT greater than or equal to 5 mm) and asymmetrical hypertrophy (AH) (max RVWT/min RVWT greater than or equal to 1.3) of the RV in HCM, HT-ASH and mild HT were 67% and 41%, 57% and 45%, and 15% and 11%, respectively. The incidence of RVH with AH was more frequent in patients with HCM as well as HT with ASH than in patients with HT without ASH.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:4093619

  7. Differential expression of cyclooxygenases in hypertrophic scar and keloid tissues.

    PubMed

    Rossiello, Luigi; D'Andrea, Francesco; Grella, Roberto; Signoriello, Giuseppe; Abbondanza, Ciro; De Rosa, Caterina; Prudente, Mariaevelina; Morlando, Marianna; Rossiello, Raffaele

    2009-01-01

    Hypertrophic scar (HS) and keloid (KL) are two forms of an abnormal cutaneous scarring process, mainly characterized by excessive extracellular matrix deposition and fibroblast proliferation. Despite the increased understanding of the molecular and cellular events leading to HS and KL, the pathogenesis of these lesions remains poorly understood. A pivotal role in the formation of abnormal scars has been ascribed to transforming growth factor-beta, whose activity appears to be mediated through a link with pathways acting via cyclooxygenases (COX-1 and COX-2). To date, there is no report on the in vivo expression of COX-1 and COX-2 in human HS and KL tissues. Therefore, using immunohistochemistry and Western blot analysis, we investigated 36 cases of KL, 32 cases of HS, and 25 cases of normal skin in order to define the localization and distribution of COX-1 and COX-2 in the tissues of these scar lesions and the overlying epidermis. The results mainly show the following: (a) a significant overexpression of COX-1 in HS tissues and the overlying epidermis as compared with normal skin and KL tissues and (b) a significant overexpression of COX-2 in KL tissue and the overlying epidermis in contrast to normal skin and HS tissues. Our data support the hypothesis that both COXs are involved in the pathogenesis of scar lesions in different ways and, particularly, COX-1 in the formation of HS and COX-2 in the formation of KL. In addition, the overexpression of COX-1 and COX-2 in the epidermis overlying HS and KL tissues, respectively, underlines the importance of epithelial-mesenchymal interactions in the pathogenesis of scar lesions. PMID:19769727

  8. Hypertrophic lichen planus versus prurigo nodularis: a dermoscopic perspective

    PubMed Central

    Ankad, Balachandra S.; Beergouder, Savitha L.

    2016-01-01

    Background: Hypertrophic lichen planus (HLP) classically involves shin and ankles and is characterized by hyperkeratotic plaques and nodules. Prurigo nodularis (PN) is a chronic neurodermatitis that presents with intensely pruritic nodules. Histopathology of HLP and PN demonstrate epidermal hyperplasia, hypergranulosis, and compact hyperkeratosis. The dermis shows vertically arranged collagen fibers and an increased number of fibroblasts and capillaries in both conditions. Moreover, basal cell degeneration is confined to the tips of rete ridges, and band-like infiltration is conspicuously absent in HLP. Therefore, both conditions mimic each other clinically, which makes diagnosis difficult. Hence, there is a need for a diagnostic technique to differentiate both conditions. Objective: To evaluate dermoscopic patterns in HLP and PN and to study these patterns histopathologically. Materials and methods: The study was conducted at S. Nijalingappa Medical College in Bagalkot. It was an observational case series study. Ethical clearance and informed consent was obtained. A Dermlite 3 dermoscope (3Gen, San Juan Capistrano, CA, USA) attached to a Sony Cyber Shot camera DSC-W800 (Sony Electronics Inc., San Diego, California, USA) was employed. Histopathology was done to confirm the diagnosis. Results: There were 10 patients each with HLP and PN. HLP was seen in 8 males and 2 females. PN was observed in 7 females and 3 males. Dermoscopy of HLP demonstrated pearly white areas and peripheral striations (100%), gray-blue globules (60%), comedo-like openings (30%), red dots (40%), red globules (10%), brownish-black globules (30%), and yellowish structures (90%). In PN, red dots (70%), red globules (60%), and pearly white areas with peripheral striations (100%) were observed under dermoscopy. Conclusion: Both HLP and PN demonstrated specific dermoscopic patterns which can be demonstrated on histopathologic findings. The authors propose that these patterns are hallmarks of each

  9. Altered patterns of cardiac intercellular junction distribution in hypertrophic cardiomyopathy.

    PubMed Central

    Sepp, R.; Severs, N. J.; Gourdie, R. G.

    1996-01-01

    OBJECTIVE: To examine the distribution pattern of intercellular junctions (the mechanically coupling desmosomes and the electrically coupling gap junctions) in hypertrophic cardiomyopathy (HCM) hearts showing myofibre disarray. DESIGN: Samples from six necropsied hearts were studied, representing the interventricular septum and the free walls of the left and right ventricles. Immunohistochemical labelling of desmoplakin was used as a marker for desmosomes, and of connexin43 as a marker for gap junctions, in single and double stainings. The slides were examined by confocal laser scanning microscopy. RESULTS: Marked disorganisation of intercalated discs was observed in areas featuring myofibre disarray. Besides overall derangement, localised abnormalities in desmosome organisation were evident, which included: (1) the formation of abnormally enlarged megadiscs; (2) the presence of intersecting disc structures; and (3) aberrant side to side desmosomal connections. Gap junctional abnormalities included: (1) random distribution of gap junctions over the surface of myocytes, rather than localisation to intercalated discs; (2) abundant side to side gap junction connections between adjacent myocytes; and (3) formation of abnormally shaped gap junctions. Circles of myocytes continuously interconnected by gap junctions were also observed. Regions of the diseased hearts lacking myofibre disarray, and control hearts of normal patients and patients with other cardiac diseases, did not show these alterations. CONCLUSIONS: The disorganisation of the intercellular junctions associated with myofibre disarray in HCM may play an important role in the pathophysiological manifestations of the disease. The remodelling of gap junction distribution may underlie the formation of an arrhythmogenic substrate, thereby contributing to the generation and maintenance of cardiac arrhythmias associated with HCM. Images PMID:8944586

  10. Lake Powell

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The white ring around Lake Powell tells the story. The surface is down 98 feet. This is critical, because Powell, Lake Mead, and other lakes along the Colorado River provide water for millions of people in five states. We are in the eighth year of a drought on the Colorado River. This year was the driest year ever reported in Southern California, and there is a severe drought in Northern California, down to less than 30-percent of snow pack. This ASTER image of part of Lake Powell was acquired in 2001. The gray area depicts the shrunken, reduced 2007 lake extent compared to the extended, larger black area in 2001.

    The image covers an area of 24 x 30 km, and is centered near 37.1 degrees north latitude, 111.3 degrees west longitude.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.