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Sample records for orconectes limosus exposed

  1. Population Density of the Crayfish, Orconectes limosus, in Relation to Fish and Macroinvertebrate Densities in a Small Mesotrophic Lake - Implications for the Lake's Food Web

    NASA Astrophysics Data System (ADS)

    Haertel-Borer, Susanne S.; Zak, Dominik; Eckmann, Reiner; Baade, Ulrich; Hölker, Franz

    2005-12-01

    The population density of Orconectes limosus in a mesotrophic lake was assessed in the context of fish and macroinvertebrate biomasses, and crayfish consumption by fish. The average O. limosus (6 cm total length) abundance and biomass in the littoral zone was 2200 ind ha-1 and 32.2 kg ha1, respectively. O. limosus biomass accounted for a large percentage (49%) of the lake's macroinvertebrate biomass. O. limosus was equal to 35% of the non-predatory fish biomass and to 81% of the predatory fish biomass. O. limosus comprised 15 and 48% of the annual consumption of pike and predatory perch, respectively. Altogether, O. limosus was identified as quantitatively important for the lake's littoral food web, and might also subsidize the pelagic food web. This strengthens the need for an integrated view on lake food webs.

  2. Laboratory and field assessment of uranium trophic transfer efficiency in the crayfish Orconectes limosus fed the bivalve C. fluminea.

    PubMed

    Simon, Olivier; Garnier-Laplace, Jacqueline

    2005-09-30

    At present, ecotoxicological information regarding the impact of natural uranium (U) on freshwater ecosystems via the trophic contamination route is scarce. We generated an experimental trophic food chain involving the prey species, Corbicula fluminea, and a predator, Orconectes limosus, for a 10-day and a 30-day feeding periods (food ration: one whole soft body/day/crayfish). We studied the efficiency of U trophic transfer and the distribution of U in the predator. During the test, we varied the quantity of dietary U (from beforehand contaminated bivalves at concentrations ranging from 0.9+/-0.1 to 20.2+/-9 microg/g fw provided to each crayfish over the 10 days) applying a daily feeding rate equal to 3.9+/-0.8% fw. The efficiency of U trophic transfer from clams to crayfish varied between 1 and 13% depending on the prey exposure modalities. Accumulation of U was observed in the digestive gland but also in gills, in the muscle, and in the molt of the crayfish after trophic exposure treatments. Under high-level exposure conditions, the digestive gland was the main target-organ, however a significant accumulation was also observed in the stomach. With regard to low levels of trophic exposure, accumulation of U in gills, in the stomach, and in the digestive gland was of the same order of magnitude. Longer exposure period which incorporated a crayfish molt, resulted in a decrease of trophic transfer ratio and a modified U tissue distribution.

  3. Relative importance of direct and trophic uranium exposures in the crayfish Orconectes limosus: Implication for predicting uranium bioaccumulation and its associated toxicity.

    PubMed

    Simon, Olivier; Floriani, Magali; Camilleri, Virginie; Gilbin, Rodolphe; Frelon, Sandrine

    2013-02-01

    Pollutants that occur at sublethal concentrations in the environment may lead to chronic exposure in aquatic organisms. If these pollutants bioaccumulate, then organisms higher in the food chain may also be at risk. Increased attention has thus been focused on the relative importance of dietary uptake, but additional knowledge of the cellular distribution of metals after dietary exposure is required to assess the potential toxicity. The authors address concerns relating to increasing uranium (U) concentrations (from 12 µg/L to 2 mg/L) in the freshwater ecosystem caused by anthropogenic activities. The objective of the present study is to compare uranium bioaccumulation levels in tissues and in the subcellular environment. The authors focused on the cytosol fraction and its microlocalization (TEM-EDX) in the gills and the hepatopancreas (HP) of the crayfish Orconectes limosus after 10 d of direct exposure (at concentrations of 20, 100, and 500 µg/L) and five trophic exposure treatments (at concentrations from 1 to 20 µg/g). Results indicated that adsorption of uranium on the cuticle represents the main contribution of total uranium accumulation to the animal. Accumulation in the gills should be considered only as a marker of waterborne uranium exposure. Accumulation in the HP after trophic environmental exposure conditions was higher (18.9 ± 3.8 µg/g) than after direct exposure. Moreover, no significant difference in the subcellular distribution of uranium (50%) in HP was observed between animals that had been exposed to both types of treatment. A potential toxic effect after uranium accumulation could therefore exist after trophic exposure. This confirms the need to focus further studies on the metal (uranium) risk assessment.

  4. Temporal dynamics of spore release of the crayfish plague pathogen from its natural host, American spiny-cheek crayfish (Orconectes limosus), evaluated by transmission experiments.

    PubMed

    Svoboda, J; Kozubíková-Balcarová, E; Kouba, A; Buřič, M; Kozák, P; Diéguez-Uribeondo, J; Petrusek, A

    2013-05-01

    The crayfish plague pathogen, Aphanomyces astaci, is one of the most serious threats to indigenous European crayfish species. The North American invasive spiny-cheek crayfish, Orconectes limosus, is an important source of this pathogen in central and western Europe. We evaluated potential changes in A. astaci spore release rate from infected individuals of this species by experiments investigating the pathogen transmission to susceptible noble crayfish, Astacus astacus. We filtered defined volumes of water regularly to quantify spore concentration, and sampled crayfish tissues at the end of the experiment. The filters and tissues were then tested for the presence of A. astaci DNA by species-specific quantitative PCR. Additionally, we tested the efficiency of horizontal transmission to apparently uninfected O. limosus. The experiments confirmed that A. astaci can be transmitted to susceptible crayfish during intermoult periods, and that the pathogen was more frequently detected in noble crayfish recipients than in American ones. The pathogen spore concentrations substantially varied in time, and significantly increased during moulting of infected hosts. Our study strengthens the evidence that although the likelihood of crayfish plague transmission by water transfer from localities with infected American crayfish might increase when these are moulting or dying, no time-periods can be proclaimed safe.

  5. Draft genome sequence of Inquilinus limosus strain MP06, a multidrug-resistant clinical isolate

    PubMed Central

    Pino, Marylú; Conza, José Di; Gutkind, Gabriel

    2015-01-01

    The bacterium, Inquilinus limosus, with its remarkable antimicrobial multiresistant profile, has increasingly been isolated in cystic fibrosis patients. We report draft genome sequence of a strain MP06, which is of considerable interest in elucidating the associated mechanisms of antibiotic resistance in this bacterium and for an insight about its persistence in airways of these patients. PMID:26691451

  6. Crayfish (Orconectes virilis) predation on zebra mussels (Dreissena polymorpha)

    USGS Publications Warehouse

    Love, Joy; Savino, Jacqueline F.

    1993-01-01

    In laboratory studies, we quantified predation rates and handling time of crayfish (Orconectes virilis) on zebra mussels (Dreissena polymorpha) and rainbow trout (Oncorhhynchus mykiss) eggs. In single prey species tests, crayfish ate zebra mussels at similar rates as they ate rainbow trout eggs. When both prey were present, crayfish preferred rainbow trout eggs. Handling time of mussels was about twice that of rainbow trout eggs, and energetic content of mussels was lower. Therefore, net benefit for foraging on rainbow trout eggs was about three times that of foraging on zebra mussels.

  7. The Effects of Biodiesel and Crude Oil on the Foraging Behavior of Rusty Crayfish, Orconectes rusticus.

    PubMed

    Jurcak, Ana M; Gauthier, Steven J; Moore, Paul A

    2015-11-01

    Environmental pollutants, such as crude oil and other petroleum-based fuels, inhibit and limit an organism's ability to perceive a chemical stimulus. Despite the increased use of alternative fuels, such as biodiesel, there have been few studies investigating the impact of these chemicals on the behavior of aquatic organisms. The purpose of this study was to compare the sublethal effects of biodiesel and crude oil exposure on chemically mediated behaviors in a freshwater keystone species. Crayfish (Orconectes rusticus) were tested on their ability to respond appropriately to a positive chemical stimulus within a Y-maze choice paradigm. Behavior was quantified by measuring time spent finding an odor source, duration of time spent at the odor source, percentage of crayfish that found the odor source, and percentage of crayfish that chose the correct arm of the arena. Results indicated negative impacts of both biodiesel and crude oil on the ability of crayfish to locate the food source. However, there were no significant differences between behavioral performances when crayfish were exposed to crude oil compared with biodiesel. Thus, biodiesel and crude oil have equally negative effects on the chemosensory behavior of crayfish. These findings indicate that biodiesel has the potential to have similar negative ecological impacts as other fuel source toxins.

  8. Olfactory Sampling Recovery Following Sublethal Copper Exposure in the Rusty Crayfish, Orconectes rusticus.

    PubMed

    Lahman, Sara E; Moore, Paul A

    2015-10-01

    Increasing levels of anthropogenic chemicals within an aquatic ecosystem may inhibit animals from extracting information from chemical signals. We investigated whether antennular flicking, a behavioral mechanism involved in chemically-mediated behaviors of the rusty crayfish, Orconectes rusticus, was altered following a sublethal copper exposure (450 µg/L). Crayfish exposed to copper exhibited lower flicking rates than control crayfish and were significantly less successful in their ability to orient to a food odor. Copper was then eliminated from the housing tanks, providing a recovery period. Groups of crayfish were assayed for antennular flicking rates and orientation success three times over the course of the 21 day recovery period. Crayfish demonstrated significant increases in rates of successful localization of odors and antennular flicking during this portion of the experiment. These results indicate that the mechanism by which copper impairs chemoreception in the rusty crayfish is reversible if elevated levels of copper concentrations are eliminated from aquatic ecosystems contaminated by runoff from agricultural or aquacultural chemicals.

  9. Sublethal copper toxicity impairs chemical orientation in the crayfish, Orconectes rusticus.

    PubMed

    Lahman, Sara E; Trent, Kaitlyn R; Moore, Paul A

    2015-03-01

    Before reaching concentrations that are high enough to cause mortality, elevated levels of chemical pollution can significantly alter a keystone indicator species' ability to extract sensory information. To organisms that rely on chemical signals to make crucial ecological decisions, increased amounts of a pollutant may impact chemoreceptive abilities by altering the perception of the sensory landscape or impairing the functioning of sensory organs. Heavy metal pollutants entering an aquatic ecosystem are of increasing concern due to discernible effects on chemoreception in many ecologically and economically important species. In order to determine the effects of sublethal copper toxicity on chemically mediated behavior, male and female rusty crayfish, Orconectes rusticus, were exposed to ecologically relevant concentrations of copper (4.5, 45, and 450 µg/l) for 120 h. Following exposure, crayfish were allowed to orient toward a food odor stimulus. During orientation trials, select crayfish oriented under a point or nonpoint source copper background pollutant at the same concentration as the exposure period. Orientation trials were videotaped and analyzed using EthoVision XT 8.5 (Noldus Information Technology, The Netherlands) for differences in overall success in locating the food source and orienting parameters. Significant differences were found in the overall orientation ability of O. rusticus to locate an odor source when previously exposed to copper in combination with a source of pollution in the background of orientation trials. Crayfish exposed to copper in any capacity during the experiment (regardless of concentration or background during trials) showed slower walking speeds toward the source, decreased turning angles, increased heading angles toward the source, and decreased upstream heading angles. Results from this experiment support that copper impairs the ability of crayfish to detect, process, and/or respond appropriately to chemosensory

  10. Characterizing the Invasion Front of the Rusty Crayfish, Orconectes Rusticus, in a Pennsylvania Stream

    NASA Astrophysics Data System (ADS)

    Wagner, J. M.; Wallace, J. R.; Perry, W. L.

    2005-05-01

    The rusty crayfish, Orconectes rusticus, was an unknown species in Pennsylvania during the last major assessment of crayfish as documented in a 1906 survey. An intensive survey of Lancaster County, Pennsylvania in 2000 revealed that O. rusticus had successfully invaded many streams. Orconectes rusticus are also sold in local bait shops suggesting its introduction was likely due to its use as bait. Orconectes rusticus has the potential to cause serious ecological harm to aquatic systems by displacing native crayfish species via competition and hybridization leading to alteration of food web dynamics. In order to predict the extent of invasions, identification of the physical and chemical parameters predisposing stream habitats to invasion is needed. Our objectives were to determine how a suite of physical and chemical parameters might influence the distribution of crayfish species along a stream continuum, with particular emphasis on characterizing the invasion front of Orconectes rusticus. Rather than an invasion front, we encountered a distinct invasion boundary created by a natural series of small waterfalls. Our data suggest that parameters such as water velocity, depth, pH, and temperature have little effect on the distribution and invasion of Orconectes rusticus along a stream continuum when natural barriers are present.

  11. The effects of bt corn on rusty crayfish (Orconectes rusticus) growth and survival.

    PubMed

    Linn, Matthew D; Moore, Paul A

    2014-10-01

    Bt crops are one of the most commonly used genetically modified crops worldwide. Bt crops contain a gene that is derived from the bacteria Bacillus thuringiensis, which produces the Cry1Ab toxin. Bt corn that contains the Cry1Ab toxin is used throughout the Midwest United States to control crop pests such as the European corn borer (Ostrinia nubilalis). Headwater streams in regions known for intensive agriculture receive Bt corn detritus after the fall harvest, which is then consumed by a diverse community of stream invertebrates. The rusty crayfish (Orconectes rusticus) is a common invertebrate detritivore in these headwater streams. Both isogenic and Bt corn were grown under the controlled environmental conditions of a greenhouse and, after senescence, were tested for nutritional equality. Rusty crayfish were exposed to one of several detrital treatments composed of Bt corn, Bt corn plus American sycamore (Platanus occidentalis), isogenic corn alone, isogenic corn plus P. occidentalis, or P. occidentalis alone for 8 weeks. Both strains of corn were grown under the controlled environmental conditions in a greenhouse and were tested for nutritional equality after senescence. Crayfish were housed in live streams with a water temperature of 12.8 °C and a 12:12 h light-to-dark photoperiod. Survival and growth of animals within each experimental treatment were monitored each week. After 8 weeks of exposure, there was no statistically significant difference in growth between crayfish in Bt and isogenic treatments. However, survivorship was 31 % lower in the Bt treatment compared with the isogenic treatment. These results suggest that the Bt corn and isogenic corn were of equivalent nutritional value but that Bt corn does have a toxic effect on rusty crayfish during long-term exposure.

  12. Assessing ecosystem vulnerability to invasive rusty crayfish (Orconectes rusticus).

    PubMed

    Olden, Julian D; Vander Zanden, M Jake; Johnson, Pieter T J

    2011-10-01

    Despite the widespread introduction of nonnative species and the heterogeneity of ecosystems in their sensitivity to ecological impacts, few studies have assessed ecosystem vulnerability to the entire invasion process, from arrival to establishment and impacts. Our study addresses this challenge by presenting a probabilistic, spatially explicit approach to predicting ecosystem vulnerability to species invasions. Using the freshwater-rich landscapes of Wisconsin, USA, we model invasive rusty crayfish (Orconectes rusticus) as a function of exposure risk (i.e., likelihood of introduction and establishment of O. rusticus based on a species distribution model) and the sensitivity of the recipient community (i.e., likelihood of impacts on native O. virilis and O. propinquus based on a retrospective analysis of population changes). Artificial neural networks predicted that approximately 10% of 4200 surveyed lakes (n = 388) and approximately 25% of mapped streams (23 523 km total length) are suitable for O. rusticus introduction and establishment. A comparison of repeated surveys before vs. post-1985 revealed that O. virilis was six times as likely and O. propinquus was twice as likely to be extirpated in streams invaded by O. rusticus, compared to streams that were not invaded. Similarly, O. virilis was extirpated in over three-quarters of lakes invaded by O. rusticus compared to half of the uninvaded lakes, whereas no difference was observed for O. propinquus. We identified 115 lakes (approximately 3% of lakes) and approximately 5000 km of streams (approximately 6% of streams) with a 25% chance of introduction, establishment, and extirpation by O. rusticus of either native congener. By identifying highly vulnerable ecosystems, our study offers an effective strategy for prioritizing on-the-ground management action and informing decisions about the most efficient allocation of resources. Moreover, our results provide the flexibility for stakeholders to identify priority

  13. Effects of sublethal exposure to cadmium on shelter-seeking behavior of juvenile Orconectes rusticus (Girard) crayfish

    SciTech Connect

    Alberstadt, P.; Steele, C.; Misra, K.; Skinner, C.; Wilson, B.; Robaskiewicz, S.

    1999-07-01

    Sublethal behavioral effect of heavy metals on crayfishes may adversely effect their survival in the environment. They may experience increased predation due to changes in their ability to remain in or under shelter. The effect of sublethal cadmium exposure on the ability of juvenile Orconectes rusticus crayfish to remain in shelter was evaluated. Four different treatment groups were used: a control group not exposed to cadmium, and three experimental groups exposed to 1, 2 ,or 3 mg Cd/L for 7 days. Crayfish were placed, individually, into small glass aquaria containing 3 L of laboratory water, with continuous aeration. Each crayfish was provided with a dark, thigmotactic shelter. Cadmium was introduced into the aquaria on days 1 and 4 to establish and maintain the nominal concentration. On days 5 through 7, observations were taken on each crayfish five times per day, with a minimum of 30 minutes between observations. The locations of the animals were recorded as in cover or in the open area of an aquarium. Repeated measures ANOVA was used to examine the effects of sublethal exposure to cadmium on shelter use by the juveniles.

  14. The Effect of the Crayfish Orconectes virilis (Crustacea: Decapoda: Cambaridae) in the Decomposition and Succession of Submerged Small Mammal Carrion

    NASA Astrophysics Data System (ADS)

    de Jong, G. D.; Chadwick, J. W.

    2005-05-01

    The role of the crayfish Orconectes virilis in the decomposition of submerged rat carrion and succession of other benthic macroinvertebrates was experimentally investigated in Slaughterhouse Gulch, a small, urban stream in Littleton, Colorado. Crayfish participation in carrion decomposition significantly altered the decomposition rate of the carrion. Nine carcasses were exposed in anchored minnow traps at three degrees of crayfish access: crayfish always present, crayfish having free access, and crayfish excluded. These three treatments required 23 days, 29 days, and 65 days, respectively, for complete decomposition of the rat carrion (<2% original biomass). Sample variability increased with number of crayfish present, especially as decomposition proceeded. Seven other macroinvertebrate taxa were collected from the carcasses, but their presence or absence could not be correlated with crayfish presence. The leech Haemopis marmoratus was generally the first macroinvertebrate to arrive at the carrion, being present in densities of <5 individuals/carcass early in succession and in larger densities (up to 25 individuals/carcass) after extensive decomposition and exposure of the viscera.

  15. Fine structure of the spermatozoon in three species of Cambaridae (Arthropoda: Crustacea: Decapoda) Cambarus robustus, Orconectes propinquus and Orconectes rusticus: a comparative biometrical study

    PubMed Central

    Yazicioglu, Buket; Hamr, Přemek; Kozák, Pavel

    2016-01-01

    The ultrastructure of spermatozoa in three species of cambarid crayfish, Cambarus robustus, Orconectes propinquus, and Orconectes rusticus, were studied and compared with eight previously studied species from different crayfish families using morphological features and biometrical data. The ultrastructure of spermatozoa show a generally conserved pattern including an acrosome and nucleus in the anterior and posterior parts of the cell, respectively, radial arms that wrap around the nucleus, and the whole cell is enclosed by an extracellular capsule. The most outstanding morphological feature in spermatozoa of three studied cambarid crayfish is the crest-like protrusions in the anterior part of the acrosome that can be used as one of the features for distinguishing the members of this family. Results of biometrical data reveal that acrosome size in the representatives of Parastacidae are the smallest, while representatives of Astacidae show the biggest acrosome. The acrosome size in species belonging to Cambaridae occupy an intermediate position between the two other families of freshwater crayfish. In conclusion, a combination of morphological features and biometrical data of spermatozoa can help distinguishing different species of the freshwater crayfish. PMID:27635333

  16. Acute toxicity and accumulation of zinc in the crayfish, Orconectes virilis (Hagen)

    SciTech Connect

    Not Available

    1986-09-01

    Zinc produces acute toxicity to freshwater organisms over a range of concentrations from 90 to 58, 100..mu..g Zn/L; with the range of acute median effect concentrations being similar for freshwater fish and invertebrates. The capacity to regulate internal zinc concentrations in decapod crustaceans has been described. Studies with the crayfish Austropotambius pallipes suggested a relatively high degree of tolerance to zinc by this animal. The present study is designed to describe the toxicity of zinc to the crayfish Orconectes virilis over a 2-wk exposure period. In addition, whole animal and tissue analyses were performed on the test organisms and compared to previous results.

  17. Crayfish (Orconectes virilis) feeding on young lake trout (Salvelinus namaycush): effect of rock size

    USGS Publications Warehouse

    Savino, Jacqueline F.; Miller, John E.

    1991-01-01

    In laboratory studies, we quantified predation rates of crayfish (Orconectes virilis) on the eggs and sac fry of lake trout (Salvelinus namaycush) and a surrogate species, rainbow trout (Oncorhynchus mvkiss), dispersed among different sized substrates (bare bottom, gravel, cobble, large rocks). Predation was most severe when no rocks were present. Feeding rate then decreased as the substrate changed from large rocks to cobble to gravel. Crayfish predation rate did not change with prey type—rainbow trout and lake trout eggs or sac fry. Crayfish foraging in large tanks containing cobble averaged about two eggs or sac fry per day. In most instances, crayfish would have little impact on lake trout egg survival. Only in lake trout spawning grounds with relatively low egg densities, large crayfish populations, and cobble or large rock substrate, would crayfish be expected to have some impact on lake trout egg survival.

  18. Ontogenetic Variation in Food Consumption of Rusty Crayfish (Orconectes rusticus) in a Central New York Stream

    USGS Publications Warehouse

    Johnson, James H.; Nack, Christopher C.

    2010-01-01

    We examined feeding periodicity of three size groups of the rusty crayfish (Orconectes rusticus) at four-hour intervals over a 28-hour period during July in a headwater stream of the Susquehanna River drainage in central New York. Feeding activity was expressed as the ratio of stomach weight divided by the crayfish wet weight. The diel food consumption patterns of all three size groups of rusty crayfish (i.e., ≤ 10 mm, 11–20 mm, and > 20 mm carapace length) were significantly different. Peak feeding of the smallest crayfish occurred during crepuscular periods. Food consumption of the intermediate size crayfish was highest at 2000 h, and feeding of large crayfish was consistently high from 1200 h to 0400 h. Feeding intensity of both small and intermediate size crayfish was highest when feeding intensity of large crayfsh was lowest. Ontogenetic differences in feeding periodicity may be associated with predation pressure from large rusty crayfish on smaller individuals.

  19. Ontogenetic variation in food consumption of rusty crayfish (Orconectes rusticus) in a central New York stream

    USGS Publications Warehouse

    Johnson, J.H.; Nack, C.C.

    2010-01-01

    We examined feeding periodicity of three size groups of the rusty crayfish (Orconectes rusticus) at four-hour intervals over a 28-hour period during July in a headwater stream of the Susquehanna River drainage in central New York. Feeding activity was expressed as the ratio of stomach weight divided by the crayfish wet weight. The diel food consumption patterns of all three size groups of rusty crayfish (i.e., ??? 10 mm, 11-20 mm, and > 20 mm carapace length) were significantly different. Peak feeding of the smallest crayfish occurred during crepuscular periods. Food consumption of the intermediate size crayfish was highest at 2000 h, and feeding of large crayfish was consistently high from 1200 h to 0400 h. Feeding intensity of both small and intermediate size crayfish was highest when feeding intensity of large crayfsh was lowest. Ontogenetic differences in feeding periodicity may be associated with predation pressure from large rusty crayfish on smaller individuals.

  20. Population genetic structure of the crayfish,Orconectes juvenilis, in central Kentucky

    NASA Astrophysics Data System (ADS)

    Ziemba, R.; Reneer, D.; Buhay, J.; Crandall, K.

    2005-05-01

    Orconectes juvenilis is distributed throughout the Kentucky River basin and surrounding drainages. Little is known about the patterns of gene flow between populations of this species, but such information is critical for understanding patterns of diversification in the genus and in conservation planning for the group. We assessed sequence-level variation in the 16S region of mitochondrial DNA within and among fourteen populations of O. juvenilis. We also compared these data to sequences collected from two populations of O. cristavarius and one population of O. rusticus, two closely related species. The geographic distribution of haplotypes and patterns of mtDNA polymorphism are consistent with current isolation among some populations and suggest recent population growth, perhaps associated with geographic expansion. The data also suggest gene flow between morphologically divergent populations of O. juvenilis and O. cristavarius.

  1. Do antennule and aesthetasc structure in the crayfish Orconectes virilis correlate with flow habitat?

    PubMed

    Mead, Kristina S

    2008-12-01

    The local flow environment affects the shape of waterborne chemical signals through a variety of physical mechanisms and at several scales. Since crayfish rely on these chemical signals to extract information about predators, prey, and mates, one might expect the chemical sensors (aesthetascs) on crayfish antennules to be physically tuned to the presentation of chemical cues by the flow environment. This hypothesis was tested by comparing length, diameter, and spacing of antennules and aesthetascs among geographically distinct populations of Orconectes virilis. Crayfish were collected from the Chagrin river, Hebron hatchery, and Burt lake. In addition, antennules were sampled from 43 museum populations representing 12 lake, 10 creek, and 21 river populations from multiple states and river drainages. Mean velocities from the collection sites were either measured directly or calculated from United States Geological Survey (USGS) historical data. Structural parameters were measured using Scion Image software on Scanning electron microscope micrographs, and analyses of variance were performed using StatView. Structural parameters of aesthetascs were found to vary with flow environment. Aesthetascs from lake populations were inserted at a larger angle, extended out farther from the supporting antennule relative to the width of the antennule, and were more widely spaced than aesthetascs from creek, hatchery, and river populations.

  2. Effectiveness of two commercial rotenone formulations in the eradication of virile crayfish Orconectes virillis

    USGS Publications Warehouse

    Recsetar, Matthew S.; Bonar, Scott A.

    2015-01-01

    The virile or northern crayfish Orconectes virilis is an invasive species throughout much of the USA, damaging aquatic communities where it is introduced. Therefore, identification of effective methods for its eradication from areas in which it is unwanted is important. We studied the effectiveness of two commercial formulations of rotenone, Chem Fish Regular and CFT Legumine, for virile crayfish control. Although both formulations were effective for fish eradication, earlier observations by fisheries managers suggested that the relative effectiveness of the two formulations differs for crayfish. The only noteworthy difference between the formulations is that the former contains a synergist. In our first experiment, we tested each toxicant at the maximum labeled dosage (5 ppm) and found CFT Legumine to be 100% ineffective (0% mortality), while the Chem Fish Regular treatment resulted in 12.5% mortality. After we deemed Chem Fish Regular to be the only toxicant with any effectiveness against virile crayfish, we tested concentrations from 5 to 50 ppm and found 10 times the maximum labeled dosage (50 ppm rotenone) was needed to kill all virile crayfish. Because crayfish burrow and can leave water, and because 100% eradication is usually desired, rotenone applied at the labeled rates will not be effective for crayfish control. However, treating a body of water with CFT Legumine to eradicate invasive fish while leaving desirable crayfish unharmed is possible.

  3. Competition for food between crayfish (Orconectes virilis) and the slimy sculpin (Cottus cognatus)

    USGS Publications Warehouse

    Miller, John E.; Savino, Jacqueline F.; Neely, Robert K.

    1992-01-01

    Interspecific competition for a food resource (fish eggs) was examined in a laboratory setting between two common benthic organisms of the Great Lakes, the slimy sculpin (Cottus cognatus) and crayfish (Orconectes virilis). In monospecific tests, the median egg predation in aquarium microcosms ranged from 2.5 eggs/d for the sculpin to 3.0 eggs/d for the crayfish. In mixed-species tests, sculpin feeding rates were no different than in the monospecific tests. Feeding rates for crayfish, however, were significantly reduced by the presence of sculpin. In mixed-species treatments in which small refuges were included in the aquaria, crayfish predation of eggs was 50% less than in the monospecific tests, i.e., 1.5 eggs/d, and, crayfish went on 93% fewer excursions outside refuges, spent 94% less time outside refuges, and engaged in 83% fewer feeding bouts than sculpin (P≤ 0.05 for all comparisons). When no refuges were provided, crayfish ceased feeding (0 eggs/d). These results suggest the potential for an asymmetrical competitive interaction in a natural setting in which crayfish may be forced into a suboptimal diet by such an interaction with the slimy sculpin.

  4. A trematode parasite alters growth, feeding behavior, and demographic success of invasive rusty crayfish (Orconectes rusticus).

    PubMed

    Sargent, Lindsey W; Baldridge, Ashley K; Vega-Ross, Maraliz; Towle, Kevin M; Lodge, David M

    2014-07-01

    Nonindigenous species can cause major changes to community interactions and ecosystem processes. The strong impacts of these species are often attributed to their high demographic success. While the importance of enemy release in facilitating invasions has often been emphasized, few studies have addressed the role of parasites in the invasive range in controlling demographic success of potential invaders. Here we examine whether a trematode parasite (Microphallus spp.) can contribute to previously documented alternate states in the abundance of invasive rusty crayfish (Orconectes rusticus) in north temperate lakes in Wisconsin, USA. Microphallus infect O. rusticus after emerging from their first intermediate host, a hydrobiid snail. As previously documented, O. rusticus reduce densities of hydrobiid snails through direct predation and destruction of macrophyte habitat. Therefore, if Microphallus substantially reduce O. rusticus fitness, these parasites may reinforce a state of low crayfish abundance, and, at the other extreme, abundant crayfish may repress these parasites, reinforcing a state of high crayfish abundance. From samples collected from 109 sites in 16 lakes, we discovered (1) a positive relationship between crayfish infection intensity and hydrobiid snail abundance, (2) a negative relationship between parasite prevalence and crayfish abundance, and (3) a negative relationship between parasite prevalence and crayfish population growth. With experiments, we found that infection with Microphallus reduced foraging behavior and growth in O. rusticus, which may be the mechanisms responsible for the population reductions we observed. Overall results are consistent with the hypothesis that Microphallus contributes to alternate states in the abundance and impacts of O. rusticus.

  5. Effects of Current Velocity, Particle Size, and Substrate Heterogeneity on Crayfish (Orconectes propinquus) Activity

    NASA Astrophysics Data System (ADS)

    Clark, J. M.; Kershner, M. W.

    2005-05-01

    The use of flow refugia (e.g., substrate) by lotic invertebrates often increases their likelihood of survival during flood events. Movement to potential refugia becomes risky as velocities increase, and the range of velocities that benthic invertebrates can withstand is variable. In this study, activity time and slip velocities of small [carapace length (CL)=10-20 mm] and large (CL=20-30 mm) Orconectes propinquus were measured in an artificial flume across ranges of current velocity and substrate heterogeneity. Particle sizes included small pebbles (16-32 mm), large pebbles (32-64 mm), and small cobble (64-128 mm). Water velocity was increased by 0.1 m/s increments from 0.1-1.5 m/s at 5-minute intervals or until the crayfish was dislodged from the substrate. As current velocity increased, the probability of slipping increased for all crayfish. Regardless of the degree of substrate heterogeneity, small crayfish held their position at higher velocities than large crayfish and were also less active. Slip rates were generally lower for both sizes as substrate heterogeneity increased. Essentially, the availability and probability of finding refugia increased with increased habitat heterogeneity and allowed crayfish to avoid being swept into the drift.

  6. Preliminary investigation of effects of sublethal acid exposure on maternal behavior in the Crayfish Orconectes virilis

    SciTech Connect

    France, R.L.

    1985-11-01

    The occurrence of crayfish inhabiting the littoral regions of many oligotrophic acid sensitive lakes makes these organisms vulnerable to spring pH decreases. Egg extrusion in Orconectes spp. found in south-central Ontario is generally synchronous and occurs during or slightly after ice melting in late April, a time at which these lakes receive between 36-77% of the year's export of H from their watersheds. To understand how a toxicant affects crayfish reproduction it is necessary that the maternal and embryonic responses to experimental perturbation be separated. In an acidified lake in the Experimental Lakes Area, northwestern Ontario, 6.9-16.9% of the egg-bearing females experienced partial mortality of their broods at pH 5.4-5.6. An ancillary experiment was undertaken here to determine if this egg mortality could be a result of low pH-induced behavioral modification of the maternal female, rather than direct acid toxicity to the developing eggs.

  7. Habitat use and growth of the western painted crayfish Orconectes palmeri longimanus

    USGS Publications Warehouse

    Dyer, Joseph J.; Mouser, Joshua; Brewer, Shannon K.

    2016-01-01

    Identifying ontogenetic shifts in habitat use by aquatic organisms is necessary for improving conservation strategies; however, our ability to designate life stages based on surrogate metrics (i.e., length) is questionable without validation. This study identified growth patterns of age-0 western painted crayfish Orconectes palmeri longimanus (Faxon, 1898) reared in the laboratory, provided support for field-based designations of age-0 lengths, and identified microhabitat factors important to adult and juvenile presence from field collections. Two growth periods of a laboratory crayfish population were described using a broken line model: a rapid, early-growth period (weeks 2-20, slope = 0.81 ± 0.03SE), and a slower, late-growth period (weeks 22-50, slope = 0.13 ± 0.03SE). A smoothed curve was generated to represent the size distribution of juveniles from our laboratory population to determine the probability that an age-0 crayfish from our laboratory population had a carapace length (CL) similar to that found in previous field studies using onset of maturity (22.4 mm CL). We determined that the probability of the age-0 crayfish in our summer laboratory population exceeding 22.4 mm CL was 0.06. The threshold between the lower 0.95 and upper 0.05 probabilities was 22.9 mm CL, confirming previous field observations of onset at maturity. We used this threshold to identify juveniles and adults from our field collections, and found that both life stages were positively associated with coarse substrate and negatively associated with water depth. Adults, however, were negatively related to gravel, whereas juveniles showed a positive relationship. This result is reflective of the relationship between crayfish body size and refuge use within the interstitial spaces of substrates, whereby adult crayfish are unable to seek refuge in the small interstitial spaces of gravel.

  8. Environmental DNA (eDNA) detects the invasive rusty crayfish Orconectes rusticus at low abundances.

    PubMed

    Dougherty, Matthew M; Larson, Eric R; Renshaw, Mark A; Gantz, Crysta A; Egan, Scott P; Erickson, Daniel M; Lodge, David M

    2016-06-01

    Early detection is invaluable for the cost-effective control and eradication of invasive species, yet many traditional sampling techniques are ineffective at the low population abundances found at the onset of the invasion process. Environmental DNA (eDNA) is a promising and sensitive tool for early detection of some invasive species, but its efficacy has not yet been evaluated for many taxonomic groups and habitat types.We evaluated the ability of eDNA to detect the invasive rusty crayfish Orconectes rusticus and to reflect patterns of its relative abundance, in upper Midwest, USA, inland lakes. We paired conventional baited trapping as a measure of crayfish relative abundance with water samples for eDNA, which were analysed in the laboratory with a qPCR assay. We modelled detection probability for O. rusticus eDNA using relative abundance and site characteristics as covariates and also tested the relationship between eDNA copy number and O. rusticus relative abundance.We detected O. rusticus eDNA in all lakes where this species was collected by trapping, down to low relative abundances, as well as in two lakes where trap catch was zero. Detection probability of O. rusticus eDNA was well predicted by relative abundance of this species and lake water clarity. However, there was poor correspondence between eDNA copy number and O. rusticus relative abundance estimated by trap catches. Synthesis and applications. Our study demonstrates a field and laboratory protocol for eDNA monitoring of crayfish invasions, with results of statistical models that provide guidance of sampling effort and detection probabilities for researchers in other regions and systems. We propose eDNA be included as a tool in surveillance for invasive or imperilled crayfishes and other benthic arthropods.

  9. Acute Atrazine Exposure has Lasting Effects on Chemosensory Responses to Food Odors in Crayfish (Orconectes virilis).

    PubMed

    Belanger, Rachelle M; Mooney, Lauren N; Nguyen, Hung M; Abraham, Noor K; Peters, Tyler J; Kana, Maria A; May, Lauren A

    2016-02-01

    The herbicide atrazine is known to impact negatively olfactory-mediated behaviors in aquatic animals. We have shown that atrazine exposure has deleterious effects on olfactory-mediated behavioral responses to food odors in crayfish; however, recovery of chemosensory abilities post-atrazine exposure has not been investigated. We examined whether crayfish (Orconectes virilis) recovered chemosensory abilities after a 96-h exposure to sublethal, environmentally relevant concentrations of 80 ppb (µg/L) atrazine. Following treatment, we analyzed the ability of the crayfish to locate a food source using a Y-maze with one arm containing fish-flavored gelatin and the other containing unflavored gelatin. We compared the time spent in the food arm of the Y-maze, near the food source, as well as moving and walking speed of control and atrazine-treated crayfish. We also compared the number of crayfish that handled the food source and the amount of food consumed. Following 24-, 48-, and 72-h recovery periods in fresh water, behavioral trials were repeated to determine if there was any observable recovery of chemosensory-mediated behaviors. Atrazine-treated crayfish spent less time in the food arm, at the odor source, and were less successful at finding the food odor source than control crayfish for all times tested. Additionally, atrazine-treated crayfish consumed less fish-flavored than control crayfish; however, treatment did not affect locomotion. Overall, we found that crayfish are not able to recover chemosensory abilities 72 h post-atrazine exposure. Because crayfish rely heavily on their chemosensory abilities to acquire food, the negative impacts of atrazine exposure could affect population size in areas where atrazine is heavily applied.

  10. Ecological effects of lead mining on Ozark streams: In-situ toxicity to woodland crayfish (Orconectes hylas)

    USGS Publications Warehouse

    Allert, A.L.; Fairchild, J.F.; DiStefano, R.J.; Schmitt, C.J.; Brumbaugh, W.G.; Besser, J.M.

    2009-01-01

    The Viburnum Trend mining district in southeast Missouri, USA is one of the largest producers of lead-zinc ore in the world. Previous stream surveys found evidence of increased metal exposure and reduced population densities of crayfish immediately downstream of mining sites. We conducted an in-situ 28-d exposure to assess toxicity of mining-derived metals to the woodland crayfish (Orconectes hylas). Crayfish survival and biomass were significantly lower at mining sites than at reference and downstream sites. Metal concentrations in water, detritus, macroinvertebrates, fish, and crayfish were significantly higher at mining sites, and were negatively correlated with caged crayfish survival. These results support previous field and laboratory studies that showed mining-derived metals negatively affect O. hylas populations in streams draining the Viburnum Trend, and that in-situ toxicity testing was a valuable tool for assessing the impacts of mining on crayfish populations.

  11. Differences found in the macroinvertebrate community composition in the presence or absence of the invasive alien crayfish, Orconectes hylas

    USGS Publications Warehouse

    Freeland-Riggert, Brandye T.; Cairns, Stefan H.; Poulton, Barry C.; Riggert, Chris M.

    2016-01-01

    Introductions of alien species into aquatic ecosystems have been well documented, including invasions of crayfish species; however, little is known about the effects of these introductions on macroinvertebrate communities. The woodland crayfish (Orconectes hylas (Faxon)) has been introduced into the St. Francis River watershed in southeast Missouri and has displaced populations of native crayfish. The effects of O. hylas on macroinvertebrate community composition were investigated in a fourth-order Ozark stream at two locations, one with the presence of O. hylas and one without. Significant differences between sites and across four sampling periods and two habitats were found in five categories of benthic macroinvertebrate metrics: species richness, percent/composition, dominance/diversity, functional feeding groups, and biotic indices. In most seasons and habitat combinations, the invaded site had significantly higher relative abundance of riffle beetles (Coleoptera: Elmidae), and significantly lower Missouri biotic index values, total taxa richness, and both richness and relative abundance of midges (Diptera: Chironomidae). Overall study results indicate that some macroinvertebrate community differences due to the O. hylas invasion were not consistent between seasons and habitats, suggesting that further research on spatial and temporal habitat use and feeding ecology of Ozark crayfish species is needed to improve our understanding of the effects of these invasions on aquatic communities.

  12. Differences Found in the Macroinvertebrate Community Composition in the Presence or Absence of the Invasive Alien Crayfish, Orconectes hylas

    PubMed Central

    Freeland-Riggert, Brandye T.

    2016-01-01

    Introductions of alien species into aquatic ecosystems have been well documented, including invasions of crayfish species; however, little is known about the effects of these introductions on macroinvertebrate communities. The woodland crayfish (Orconectes hylas (Faxon)) has been introduced into the St. Francis River watershed in southeast Missouri and has displaced populations of native crayfish. The effects of O. hylas on macroinvertebrate community composition were investigated in a fourth-order Ozark stream at two locations, one with the presence of O. hylas and one without. Significant differences between sites and across four sampling periods and two habitats were found in five categories of benthic macroinvertebrate metrics: species richness, percent/composition, dominance/diversity, functional feeding groups, and biotic indices. In most seasons and habitat combinations, the invaded site had significantly higher relative abundance of riffle beetles (Coleoptera: Elmidae), and significantly lower Missouri biotic index values, total taxa richness, and both richness and relative abundance of midges (Diptera: Chironomidae). Overall study results indicate that some macroinvertebrate community differences due to the O. hylas invasion were not consistent between seasons and habitats, suggesting that further research on spatial and temporal habitat use and feeding ecology of Ozark crayfish species is needed to improve our understanding of the effects of these invasions on aquatic communities. PMID:26986207

  13. Differences Found in the Macroinvertebrate Community Composition in the Presence or Absence of the Invasive Alien Crayfish, Orconectes hylas.

    PubMed

    Freeland-Riggert, Brandye T; Cairns, Stefan H; Poulton, Barry C; Riggert, Christopher M

    2016-01-01

    Introductions of alien species into aquatic ecosystems have been well documented, including invasions of crayfish species; however, little is known about the effects of these introductions on macroinvertebrate communities. The woodland crayfish (Orconectes hylas (Faxon)) has been introduced into the St. Francis River watershed in southeast Missouri and has displaced populations of native crayfish. The effects of O. hylas on macroinvertebrate community composition were investigated in a fourth-order Ozark stream at two locations, one with the presence of O. hylas and one without. Significant differences between sites and across four sampling periods and two habitats were found in five categories of benthic macroinvertebrate metrics: species richness, percent/composition, dominance/diversity, functional feeding groups, and biotic indices. In most seasons and habitat combinations, the invaded site had significantly higher relative abundance of riffle beetles (Coleoptera: Elmidae), and significantly lower Missouri biotic index values, total taxa richness, and both richness and relative abundance of midges (Diptera: Chironomidae). Overall study results indicate that some macroinvertebrate community differences due to the O. hylas invasion were not consistent between seasons and habitats, suggesting that further research on spatial and temporal habitat use and feeding ecology of Ozark crayfish species is needed to improve our understanding of the effects of these invasions on aquatic communities.

  14. Evolution of invasive traits in nonindigenous species: increased survival and faster growth in invasive populations of rusty crayfish (Orconectes rusticus).

    PubMed

    Sargent, Lindsey W; Lodge, David M

    2014-09-01

    The importance of evolution in enhancing the invasiveness of species is not well understood, especially in animals. To evaluate evolution in crayfish invasions, we tested for differences in growth rate, survival, and response to predators between native and invaded range populations of rusty crayfish (Orconectes rusticus). We hypothesized that low conspecific densities during introductions into lakes would select for increased investment in growth and reproduction in invasive populations. We reared crayfish from both ranges in common garden experiments in lakes and mesocosms, the latter in which we also included treatments of predatory fish presence and food quality. In both lake and mesocosm experiments, O. rusticus from invasive populations had significantly faster growth rates and higher survival than individuals from the native range, especially in mesocosms where fish were present. There was no influence of within-range collection location on growth rate. Egg size was similar between ranges and did not affect crayfish growth. Our results, therefore, suggest that growth rate, which previous work has shown contributes to strong community-level impacts of this invasive species, has diverged since O. rusticus was introduced to the invaded range. This result highlights the need to consider evolutionary dynamics in invasive species mitigation strategies.

  15. Evolution of invasive traits in nonindigenous species: increased survival and faster growth in invasive populations of rusty crayfish (Orconectes rusticus)

    PubMed Central

    Sargent, Lindsey W; Lodge, David M

    2014-01-01

    The importance of evolution in enhancing the invasiveness of species is not well understood, especially in animals. To evaluate evolution in crayfish invasions, we tested for differences in growth rate, survival, and response to predators between native and invaded range populations of rusty crayfish (Orconectes rusticus). We hypothesized that low conspecific densities during introductions into lakes would select for increased investment in growth and reproduction in invasive populations. We reared crayfish from both ranges in common garden experiments in lakes and mesocosms, the latter in which we also included treatments of predatory fish presence and food quality. In both lake and mesocosm experiments, O. rusticus from invasive populations had significantly faster growth rates and higher survival than individuals from the native range, especially in mesocosms where fish were present. There was no influence of within-range collection location on growth rate. Egg size was similar between ranges and did not affect crayfish growth. Our results, therefore, suggest that growth rate, which previous work has shown contributes to strong community-level impacts of this invasive species, has diverged since O. rusticus was introduced to the invaded range. This result highlights the need to consider evolutionary dynamics in invasive species mitigation strategies. PMID:25469173

  16. Ionoregulatory responses of the crayfish Orconectes immunis to selenium in fresh water

    SciTech Connect

    Short, T.M.

    1983-01-01

    The purpose of this study was to investigate the effects of chronic exposure to sublethal concentrations of selenium on fluid and tissue electrolyte balance of the crayfish Orconcectes immunis. An ionic profile of O. immunis was obtained from measurements of hemolymph sodium, potassium, calcium, magnesium, and copper in several populations of crayfish in eastern Colorado. The bioassay portion of the study consisted of groups of crayfish maintained in reconstituted fresh water while exposed for 30 days to concentrations of 0.01 mg/liter, 0.10 mg/liter, or 1.00 mg/liter selenium as sodium selenite. Exposure to selenium resulted in various branchial histopathologies to include hypertrophy, necrosis, and sloughing of the cuticular membrane. Hemolymph potassium and copper, however, were significantly reduced in crayfish exposed for 10 days to 1.00 mg/liter selenium and 30 days to 0.10 mg/liter selenium. Copper appeared to be the more responsive to selenium toxicity with reductions of 47.4%-53.7% in hemolymph levels after exposure for 30 days to 1.00 mg/liter selenium. Selenium-induced changes in tissue ionic content (abdominal muscle and carapace) were most evident with respect to muscle levels of potassium and calcium. It is suggested that the observed alterations in fluid and tissue ionic content are largely in response to changes in concentration or electrochemical potential gradients brought about by selenium-induced disturbance of membrance permeability and ionic transport characteristics.

  17. Toxicological studies of cadmium and zinc on the crayfish Orconectes virilis

    SciTech Connect

    Mirenda, R.J.

    1985-01-01

    The acute toxicities of cadmium and of zinc to the crayfish Oronectes virilis were determined. Adult, intermolt crayfish were exposed to a series of concentrations of either cadmium or zinc for a two week period. Cadmium was found to be a cumulative poison to the crayfish; LC50 values decreased from 6.1 mg Cd/I for 96 hours to 0.7 mg Cd/I for two weeks. An incipient LC50 was also estimated to be 0.0604 mg Cd/I. Zinc was found to have a relatively low toxicity to O. virilis under the present exposure conditions. Whole animal and tissue analyses for cadmium or zinc were performed on the crayfish used in the acute toxicity tests. Whole animals concentrations both for cadmium and for zinc exhibited a linear relationship to exposure concentrations (r = 0.85 and 0.87, respectively). The gills had the highest concentrations (r = 0.85 and 0.87, respectively). The gills had the highest concentrations of cadmium and zinc, and displayed a linear relationship to exposure concentrations (r = 0.82 and 0.87 respectively). The hepatopancreas displayed a plateau in metal concentrations and is probably the main storage site for both metals in the crayfish. The relationship of cadmium concentration to exposure concentration in the antennal glands also showed linearity (r = 0.65), while zinc levels reached a steady state level. All the remaining tissues analyzed exhibited a plateau in metal concentration.

  18. Atrazine exposure affects the ability of crayfish (Orconectes rusticus) to localize a food odor source.

    PubMed

    Belanger, Rachelle M; Peters, Tyler J; Sabhapathy, Gita S; Khan, Sana; Katta, Juhi; Abraham, Noor K

    2015-05-01

    Environmental pollutants, found in aquatic ecosystems, have been shown to have an effect on olfactory-mediated behaviors including feeding, mate attraction, and other important social behaviors. Crayfish are polytrophic, meaning that they feed on and become prey for all levels of the aquatic food web as well as are also important for the transfer of energy between benthic and terrestrial food webs. Because crayfish are a keystone species, it is important to investigate any factors that may affect their population size. Crayfish are active at night and rely heavily on their sensory appendages (e.g., antennulues, maxillipeds, and pereopods) to localize food sources. In this experiment, we investigated the effects of atrazine (ATR) exposure on the chemosensory responses of male and female crayfish to food odors. We exposed crayfish to environmentally relevant, sublethal levels of ATR [80 ppb (µg/L)] for 72 h and then examined the behavioral responses of both ATR-treated and control crayfish to food odor delivered from one end of a test arena. We used Noldus Ethovision XT software to measure odor localization and locomotory behaviors of crayfish in response to food (fish) odor. We found that control crayfish spent more time in the proximal region of the test arena and at the odor source compared with ATR-treated crayfish. Furthermore, there were no differences in the time spent moving and not moving, total distance travelled in the tank, and walking speed (cm/s) when control and ATR-treated crayfish were compared. Overall, this indicates that acute ATR exposure alters chemosensory abilities of crayfish, whereas overall motor function remains unchanged.

  19. Regulation of crayfish, Orconectes virilis, tail muscle lactate dehydrogenase (LDH) in response to anoxic conditions is associated with alterations in phosphorylation patterns.

    PubMed

    Green, Stuart R; Storey, Kenneth B

    2016-12-01

    Lactate dehydrogenase (LDH), the terminal enzyme of anaerobic glycolysis, has a crucial role in sustaining ATP production by glycolysis during periods of anoxia via regenerating NAD(+) through the production of lactate. The present study examined the effects of prolonged (20h) anoxic submergence on LDH from the tail muscle of an anoxia-tolerant crayfish (Orconectes virilis). LDH was purified to homogeneity from tail muscle of both aerobic control and anoxic crayfish in a three step process. Analysis of the kinetic parameters and the stability of LDH showed that the Vmax in the pyruvate-reducing direction was significantly higher for the enzyme from anoxic crayfish whereas in the lactate-oxidizing direction the Vmax was significantly higher for the control enzyme. Differential scanning fluorimetry was used to assess thermal unfolding of crayfish LDH. The results showed that the enzyme from control muscle had a significantly higher melting temperature (greater thermal stability) than the anoxic enzyme form, suggesting that there was a structural difference between the two enzyme forms. Immunoblotting of purified LDH implicated post-translational modification as the reason for this difference; purified LDH from aerobic control crayfish showed significantly higher amounts of serine/threonine phosphorylation than did the anoxic enzyme form. This study provides evidence for anoxia-induced modifications of crayfish muscle LDH that may contribute significantly to modulating enzyme function under anoxic conditions.

  20. The Degree of Impairment of Foraging in Crayfish (Orconectes virilis) due to Insecticide Exposure is Dependent upon Turbulence Dispersion.

    PubMed

    Ludington, Timothy S; Moore, Paul A

    2017-02-01

    As toxicants move into aquatic systems, the concentration at any point in space or time is heavily influenced by the flow dynamics. The dispersion of these chemicals creates a toxicant concentration that fluctuates widely in time and is highly dependent on the spatial heterogeneity of turbulence. Despite this knowledge on the movement of toxicants in natural systems, most ecotoxicological studies use static exposure paradigms that ignore the spatio-temporal dynamics of toxicants in aquatic systems. Although recent studies have begun to use pulsed paradigms in an attempt to mimic natural conditions, the heterogeneity of real concentrations in natural systems rarely is considered for use in these tests. Thus, understanding how organisms are impaired by naturally distributed toxicants is relatively unknown. The purpose of this experiment was to determine how turbulent dispersion of a toxicant negatively impacts a behavioral task and if altering the nature of turbulence will change the negative impact of the toxicant. Crayfish were exposed to a turbulent plume of carbaryl, an insecticide, under two different turbulent conditions and two different spatial conditions. Turbulence was altered by placing an obstruction within the flow which mimics a natural obstruction in lentic systems. Crayfish were exposed to sublethal concentrations of carbaryl for 48 h under these different dynamic conditions. After toxicant exposure, crayfish foraging ability was measured in a flow-through Y maze. We hypothesized that crayfish exposed to the toxicant under more turbulent conditions would exhibit more detrimental responses due to the increased variation in chemical fluctuations. The fine-scale chemical distribution of the toxicant and the three-dimensional velocity profile were characterized for each of the turbulent conditions and each of the spatial locations. Analyses of these data showed that changes in turbulence or spatial location created a unique exposure condition

  1. Window contamination on Expose-R

    NASA Astrophysics Data System (ADS)

    Demets, R.; Bertrand, M.; Bolkhovitinov, A.; Bryson, K.; Colas, C.; Cottin, H.; Dettmann, J.; Ehrenfreund, P.; Elsaesser, A.; Jaramillo, E.; Lebert, M.; van Papendrecht, G.; Pereira, C.; Rohr, T.; Saiagh, K.

    2015-01-01

    Expose is a multi-user instrument for astrobiological and astrochemical experiments in space. Installed at the outer surface of the International Space Station, it enables investigators to study the impact of the open space environment on biological and biochemical test samples. Two Expose missions have been completed so far, designated as Expose-E (Rabbow et al. 2012) and Expose-R (Rabbow et al. this issue). One of the space-unique environmental factors offered by Expose is full-spectrum, ultraviolet (UV)-rich electromagnetic radiation from the Sun. This paper describes and analyses how on Expose-R, access of the test samples to Solar radiation degraded during space exposure in an unpredicted way. Several windows in front of the Sun-exposed test samples acquired a brown shade, resulting in a reduced transparency in visible light, UV and vacuum UV (VUV). Post-flight investigations revealed the discolouration to be caused by a homogenous film of cross-linked organic polymers at the inside of the windows. The chemical signature varied per sample carrier. No such films were found on windows from sealed, pressurized compartments, or on windows that had been kept out of the Sun. This suggests that volatile compounds originating from the interior of the Expose facility were cross-linked and photo-fixed by Solar irradiation at the rear side of the windows. The origin of the volatiles was not fully identified; most probably there was a variety of sources involved including the biological test samples, adhesives, plastics and printed circuit boards. The outer surface of the windows (pointing into space) was chemically impacted as well, with a probable effect on the transparency in VUV. The reported analysis of the window contamination on Expose-R is expected to help the interpretation of the scientific results and offers possibilities to mitigate this problem on future missions - in particular Expose-R2, the direct successor of Expose-R.

  2. Reproductive Plasticity in Freshwater Invader: From Long-Term Sperm Storage to Parthenogenesis

    PubMed Central

    Buřič, Miloš; Kouba, Antonín; Kozák, Pavel

    2013-01-01

    Orconectes limosus, a North American crayfish species, is one of the most important aquatic invaders in European inland waters. Despite more than 120 years occurrence in Europe and intense research, there are still gaps in knowledge of its life history and ecology. Investigation into O. limosus invasive success requires identifying the mechanisms that enabled them to establish dense and widespread populations from small initial numbers without observable limitation by an introduction bottleneck. In part, O. limosus success may lie in its ability to reproduce by facultative parthenogenesis. Moreover, there are possible other mating scenarios, because of two mating seasons (autumn and spring) in O. limosus. This work investigated the effect of four reproductive scenarios (autumn mating only, spring mating only, autumn and spring mating, and without mating) on the reproductive success of O. limosus. Females successfully reproduced in all tested mating regimes using parthenogenesis as well as log term sperm storage. This reproductive plasticity likely facilitates the overwhelming success of O. limosus spread and establishment in new localities. It can explain the spread of O. limosus from the initial introduction of 90 specimens to most of continental Europe and Great Britain. These conclusions imply a serious threat, not only for autochthonous European astacofauna, but for other aquatic organisms as well as entire ecosystems. PMID:24204886

  3. Reproductive plasticity in freshwater invader: from long-term sperm storage to parthenogenesis.

    PubMed

    Buřič, Miloš; Kouba, Antonín; Kozák, Pavel

    2013-01-01

    Orconectes limosus, a North American crayfish species, is one of the most important aquatic invaders in European inland waters. Despite more than 120 years occurrence in Europe and intense research, there are still gaps in knowledge of its life history and ecology. Investigation into O. limosus invasive success requires identifying the mechanisms that enabled them to establish dense and widespread populations from small initial numbers without observable limitation by an introduction bottleneck. In part, O. limosus success may lie in its ability to reproduce by facultative parthenogenesis. Moreover, there are possible other mating scenarios, because of two mating seasons (autumn and spring) in O. limosus. This work investigated the effect of four reproductive scenarios (autumn mating only, spring mating only, autumn and spring mating, and without mating) on the reproductive success of O. limosus. Females successfully reproduced in all tested mating regimes using parthenogenesis as well as log term sperm storage. This reproductive plasticity likely facilitates the overwhelming success of O. limosus spread and establishment in new localities. It can explain the spread of O. limosus from the initial introduction of 90 specimens to most of continental Europe and Great Britain. These conclusions imply a serious threat, not only for autochthonous European astacofauna, but for other aquatic organisms as well as entire ecosystems.

  4. Copper accumulation in the crayfish (Orconectes rusticus)

    SciTech Connect

    Evans, M.L.

    1980-06-01

    The purpose of this study was to determine whether or not the crayfish, O. rusticus could fulfill Nehring's (1976) criteria for a good biological monitor of heavy metal pollution. Since there is some evidence that the cupric ion is the most toxic form of aqueous copper, crayfish-accumulated copper was compared to both total and cupric copper in the culture water.

  5. Effect of experimental exposure to differently virulent Aphanomyces astaci strains on the immune response of the noble crayfish Astacus astacus.

    PubMed

    Becking, Thomas; Mrugała, Agata; Delaunay, Carine; Svoboda, Jiří; Raimond, Maryline; Viljamaa-Dirks, Satu; Petrusek, Adam; Grandjean, Frédéric; Braquart-Varnier, Christine

    2015-11-01

    European crayfish are sensitive to the crayfish plague pathogen, Aphanomyces astaci, carried by North American crayfish species due to their less effective immune defence mechanisms against this disease. During a controlled infection experiment with a susceptible crayfish species Astacus astacus using three A. astaci strains (representing genotype groups A, B, and E), we investigated variation in their virulence and in crayfish immune defence indicators (haemocyte density, phenoloxidase activity, and production of reactive oxygen species). Experimental crayfish were exposed to two dosages of A. astaci spores (1 and 10 spores mL(-1)). The intensity and timing of the immune response differed between the strains as well as between the spore concentrations. Stronger and faster change in each immune parameter was observed in crayfish infected with two more virulent strains, indicating a relationship between crayfish immune response and A. astaci virulence. Similarly, the immune response was stronger and was observed earlier for the higher spore concentration. For the first time, the virulence of a strain of the genotype group E (isolated from Orconectes limosus) was experimentally tested. Total mortality was reached after 10 days for the two higher spore dosages (10 and 100 spores mL(-1)), and after 16 days for the lowest (1 spore mL(-1)), revealing equally high and rapid mortality as caused by the genotype group B (from Pacifastacus leniusculus). No mortality occurred after infection with genotype group A during 60 days of the experimental trial.

  6. EXPOSE-R on Mission on the ISS

    NASA Astrophysics Data System (ADS)

    Panitz, Corinna; Rabbow, Elke; Rettberg, Petra; Barczyk, Simon; Kloss, Maria; Reitz, Guenther

    Currently EXPOSE-R is on mission! This astrobiological exposure facility was accommodated at the universal workplace URM-D Zenith payload site, located outside the Russian Svezda Module of the International Space Station (ISS) by extravehicular activity (EVA) on March 10th 2009. It contains 3 trays accommodating 12 sample compartments with sample carriers in three levels either open to space vacuum or kept in a defined gas environment. In its 8 experiments of biological and chemical content, more than 1200 individual samples are exposed to solar ultraviolet (UV) radiations, vacuum, cosmic rays or extreme temperature variations. In their different experiments the involved scientists are studying the question of life's origin on Earth and the results of their experiments are contributing to different aspects of the evolution and distribution of life in the Universe. Additionally integrated into the EXPOSE-R facility are several dosimeters monitoring the ionising and the solar UV-radiation during the mission to deliver useful information to complement the sample analysis. In close cooperation with the DLR and the Technical University Munich (TUM), the Rheinisch -Westfülische Technischen Hochschule Aachen (RWTH Aachen) operates the experiment "Spores". a This is one of the 6 astrobiological experiments of the ROSE-Consortium" (Response of Or-ganisms to Space Environment) of the EXPOSE-R mission. In these experiments spores of bacteria, fungi and ferns are being over layered or mixed with meteorite material. The analysis of the effect of the space parameters on different biological endpoints of the spores of the mi-croorganism Bacillus subtilis will be performed after the retrieval of the experiment scheduled for the end of 2010. Parallel to the space mission an identical set of samples was accommodated into EXPOSE-R trays identical in construction to perform the Mission Ground Reference (MGR) Test. Currently this MGR Test is carried out in the Planetary and Space

  7. Welding tritium exposed stainless steel

    SciTech Connect

    Kanne, W.R. Jr.

    1994-11-01

    Stainless steels that are exposed to tritium become unweldable by conventional methods due to buildup of decay helium within the metal matrix. With longer service lives expected for tritium containment systems, methods for welding on tritium exposed material will become important for repair or modification of the systems. Solid-state resistance welding and low-penetration overlay welding have been shown to mitigate helium embrittlement cracking in tritium exposed 304 stainless steel. These processes can also be used on stainless steel containing helium from neutron irradiation, such as occurs in nuclear reactors.

  8. Brucellosis in Occupationally Exposed Groups

    PubMed Central

    Sajjan, Annapurna G.; Mohite, Shivajirao T.; Gajul, Shivali

    2016-01-01

    Introduction In India, high incidence of human brucellosis may be expected, as the conditions conducive for human brucellosis exist. Limited studies have been undertaken on human brucellosis especially in occupationally-exposed groups. Aim To estimate prevalence of anti-brucellar antibodies, evaluate the clinical manifestations, risk factors and Knowledge, Attitude and Practices (KAP) levels about brucellosis among occupationally exposed groups. Materials and Methods Blood samples were collected from 2337 occupationally exposed individuals. The serum samples were screened for the presence of anti-brucellar antibodies by Rose Bengal Plate Test (RBPT), Serum Agglutination Test (SAT) and 2-Mercaptoethanol test (2-ME). Clinical manifestations, risk factors and KAP levels were evaluated by personal interview using a structured questionnaire. Results Seroprevalence of brucellosis by RBPT, SAT and 2-ME test was 9.46%, 4.45% and 3.64 % respectively. Clinical symptoms resembling brucellosis were seen in 91 subjects. The major risk factors were animal exposure in veterinarians and abattoirs, both animal exposure and raw milk ingestion in farmers and shepherds, exposure to raw milk and its ingestion in dairy workers and exposure to Brucella culture in laboratory workers. Except laboratory workers, few veterinarians and dairy workers none had heard about brucellosis. KAP levels regarding brucellosis were too poor in all the groups except laboratory workers. Conclusion Brucellosis most of the times was missed or misdiagnosed. Regular screenings for brucellosis and awareness programmes to increase KAP levels are necessary to control brucellosis in occupationally exposed groups. PMID:27190804

  9. The ORGANIC Experiment on the ISS EXPOSE-R

    NASA Astrophysics Data System (ADS)

    Bryson, K.; Peeters, Z.; Salama, F.; Foing, B.; Ehrenfreund, P.; Jessberger, E.; Bischoff, A.; Breitfellner, M.; Schmidt, W.

    2011-05-01

    Polycyclic aromatic hydrocarbons (PAHs) and aromatic networks are among the most abundant organic material in space. PAHs and fullerenes have been identified in meteorites and are proposed as carriers for numerous astronomical absorption and emission features. Recently the fullerenes C60 and C70 have been discovered in a young planetary nebula, Tc 1 and in other astronomical environments. Thin films of selected PAHs and fullerenes have been subjected to the low Earth orbit environment as part of the ORGANIC experiment on the multi-user facility EXPOSE-R, which was deployed onboard the International Space Station (ISS) in March 2009 and retrieved by extra-vehicular activity (EVA) in January 2011. The ORGANIC experiment monitors the chemical evolution, survival, destruction, and chemical modification of PAHs and fullerenes exposed to solar illumination and cosmic radiation. The radiation dose that is collected on the ISS by the samples cannot be accurately simulated in Earth laboratories. Dark samples are shielded from the UV photons and will enable us to differentiate between the effects of exposure to photons and cosmic rays. The samples are monitored before and after space exposure; ground control samples were continuously monitored. We describe the ORGANIC experiment on the Space Station and report on laboratory ground-control measurements in the UV-Vis-NIR at NASA-Ames. Extended space exposure allows us to collect data on multiple samples which can be extrapolated to other astrophysical environments and thus greatly enhance our knowledge on the evolution of organic compounds in space environment.

  10. West Virginia crayfishes (Decapoda: Cambaridae): observations on distribution, natural history, and conservation

    USGS Publications Warehouse

    Loughman, Zachary J.; Simon, Thomas P.; Welsh, Stuart A.

    2015-01-01

    West Virginia's crayfishes have received moderate attention since publication of Jezerinac et al.'s (1995) monograph of the state fauna. Survey efforts were initiated over the summers of 2006 and 2007 to gather voucher material for the Indiana Biological Survey's Crustacean Collection. These collections have provided new information regarding the distribution, natural history, life history, taxonomy, and conservation status of Cambarus (Cambarus) carinirostris, C. (C.) bartonii cavatus, C. (C.) sciotensis, C. (Hiaticambarus) chasmodactylus, C. (H.) elkensis, C. (H.) longulus, C. (Jugicambarus) dubius, C. (Puncticambarus) robustus, Orconectes (Procericambarus) cristavarius, and O. (P.) rusticus. Orconectes (Faxonius) limosus has apparently been extirpated from West Virginia and should be removed from the state's list of extant crayfishes.

  11. West Virginia crayfishes (Decapoda: Cambaridae): observations on distribution, natural history, and conservation

    USGS Publications Warehouse

    Loughman, Zachary J.; Simon, Thomas P.; Welsh, Stuart A.

    2009-01-01

    West Virginia's crayfishes have received moderate attention since publication of Jezerinac et al.'s (1995) monograph of the state fauna. Survey efforts were initiated over the summers of 2006 and 2007 to gather voucher material for the Indiana Biological Survey's Crustacean Collection. These collections have provided new information regarding the distribution, natural history, life history, taxonomy, and conservation status of Cambarus (Cambarus) carinirostris, C. (C.) bartonii cavatus, C. (C.) sciotensis, C. (Hiaticambarus) chasmodactylus, C. (H.) elkensis, C. (H.) longulus, C. (Jugicambarus) dubius, C. (Puncticambarus) robustus, Orconectes (Procericambarus) cristavarius, and O. (P.) rusticus. Orconectes (Faxonius) limosus has apparently been extirpated from West Virginia and should be removed from the state's list of extant crayfishes.

  12. Reprocessing of nonoptimally exposed holograms

    SciTech Connect

    Phipps, G.S.; Robertson, C.E.; Tamashiro, F.M.

    1980-03-01

    Two reprocessing techniques have been investigated that are capable of correcting the effects of nonoptimum optical density of photographic amplitude holograms recorded on Agfa-Gevaert type 10E75 plates. In some cases a reprocessed hologram will exhibit a diffraction efficiency even higher than that obtainable from a hologram exposed and processed to the optimum density. The SNR of the reprocessed holograms is much higher than that of the same holograms belached with cupric bromide. In some cases the SNR approaches the optimum value for a properly exposed amplitude hologram. Subjective image quality and resolution of reprocessed hologram reconstructins appear to be no different than for normal single-development holograms. Repeated reprocessing is feasible and in some cases desirable as a means of increasing diffraction efficiency.

  13. Advances in treating exposed fractures.

    PubMed

    Nogueira Giglio, Pedro; Fogaça Cristante, Alexandre; Ricardo Pécora, José; Partezani Helito, Camilo; Lei Munhoz Lima, Ana Lucia; Dos Santos Silva, Jorge

    2015-01-01

    The management of exposed fractures has been discussed since ancient times and remains of great interest to present-day orthopedics and traumatology. These injuries are still a challenge. Infection and nonunion are feared complications. Aspects of the diagnosis, classification and initial management are discussed here. Early administration of antibiotics, surgical cleaning and meticulous debridement are essential. The systemic conditions of patients with multiple trauma and the local conditions of the limb affected need to be taken into consideration. Early skeletal stabilization is necessary. Definitive fixation should be considered when possible and provisional fixation methods should be used when necessary. Early closure should be the aim, and flaps can be used for this purpose.

  14. [Drug Exposed Infants and Their Families.

    ERIC Educational Resources Information Center

    Fenichel, Emily, Ed.

    1992-01-01

    This bulletin issue addresses the theme of drug-exposed infants and the services required by these infants and their families. "Cocaine-Exposed Infants: Myths and Misunderstandings" (Barbara J. Myers and others) comments on the negative accounts of drug-exposed babies presented by mass media and reviews the mix of positive and negative…

  15. Survey of the crayfish plague pathogen presence in the Netherlands reveals a new Aphanomyces astaci carrier.

    PubMed

    Tilmans, M; Mrugała, A; Svoboda, J; Engelsma, M Y; Petie, M; Soes, D M; Nutbeam-Tuffs, S; Oidtmann, B; Roessink, I; Petrusek, A

    2014-07-01

    North American crayfish species as hosts for the crayfish plague pathogen Aphanomyces astaci contribute to the decline of native European crayfish populations. At least six American crayfish species have been reported in the Netherlands but the presence of this pathogenic oomycete with substantial conservational impact has not yet been confirmed in the country. We evaluated A. astaci prevalence in Dutch populations of six alien crustaceans using species-specific quantitative PCR. These included three confirmed crayfish carriers (Orconectes limosus, Pacifastacus leniusculus, Procambarus clarkii), two recently introduced but yet unstudied crayfish (Orconectes cf. virilis, Procambarus cf. acutus), and a catadromous crab Eriocheir sinensis. Moderate levels of infection were observed in some populations of O. limosus and P. leniusculus. Positive results were also obtained for E. sinensis and two Dutch populations of O. cf. virilis. English population of the latter species was also found infected, confirming this taxon as another A. astaci carrier in European waters. In contrast, Dutch P. clarkii seem only sporadically infected, and the pathogen was not yet detected in P. cf. acutus. Our study is the first confirmation of crayfish plague infections in the Netherlands and demonstrates substantial variation in A. astaci prevalence among potential hosts within a single region, a pattern possibly linked to their introduction history and coexistence.

  16. Preventing Alcohol-Exposed Pregnancies

    PubMed Central

    Floyd, R. Louise; Sobell, Mark; Velasquez, Mary M.; Ingersoll, Karen; Nettleman, Mary; Sobell, Linda; Mullen, Patricia Dolan; Ceperich, Sherry; von Sternberg, Kirk; Bolton, Burt; Skarpness, Bradley; Nagaraja, Jyothi

    2010-01-01

    Background Prenatal alcohol exposure is a leading preventable cause of birth defects and developmental disabilities in the United States. Design A randomized controlled trial (2002–2005; data analyzed 2005–2006) of a brief motivational intervention to reduce the risk of an alcohol-exposed pregnancy (AEP) in preconceptional women by focusing on both risk drinking and ineffective contraception use. Setting/Participants A total of 830 nonpregnant women, aged 18–44 years, and currently at risk for an AEP were recruited in six diverse settings in Florida, Texas, and Virginia. Combined settings had higher proportions of women at risk for AEP (12.5% overall) than in the general population (2%). Interventions Participants were randomized to receive information plus a brief motivational intervention (n=416) or to receive information only (n=414). The brief motivational intervention consisted of four counseling sessions and one contraception consultation and services visit. Main Outcome Measures Women consuming more than five drinks on any day or more than eight drinks per week on average, were considered risk drinkers; women who had intercourse without effective contraception were considered at risk of pregnancy. Reversing either or both risk conditions resulted in reduced risk of an AEP. Results Across the follow-up period, the odds ratios (ORs) of being at reduced risk for AEP were twofold greater in the intervention group: 3 months, 2.31 (95% confidence interval [CI]=1.69–3.20); 6 months, 2.15 (CI=1.52–3.06); 9 months, 2.11 (CI=1.47–3.03). Between-groups differences by time phase were 18.0%, 17.0%, and 14. 8%, respectively. Conclusions A brief motivational intervention can reduce the risk of an AEP. PMID:17218187

  17. Plasticity in fecundity highlights the females' importance in the spiny-cheek crayfish invasion mechanism.

    PubMed

    Pârvulescu, Lucian; Pîrvu, Mălina; Moroşan, Loredana-Giorgiana; Zaharia, Claudia

    2015-12-01

    Invasion is one of the most consequential phenomena affecting the distribution of native species. Few in number of species, European crayfish are losing the competition with introduced North American crayfish. The spiny-cheek crayfish, Orconectes limosus, is an outstanding example, successfully competing against the native narrow-clawed crayfish, Astacus leptodactylus. For four years, we collected data regarding crayfish occurrences, their relative abundance, and the structure of populations in the ongoing colonisation process of O. limosus in the lower Danube. The mature females of both invasive and indigenous crayfish species were analysed with respect to biometry and production of oocytes in relation to the dynamics of invasion. The interspecific comparisons showed no significant differences regarding body size, with an average of approximately 102 mm total length and 31 g wet weight for both species. However, the fecundity of the indigenous species was found to be constant throughout the investigated area, whereas the number of eggs produced by the invasive females was significantly increased at the active front of the invasion. The maximum number of ovarian eggs found was 887 and 1156 in the indigenous species and the invasive species, respectively. We propose the scenario that the invasive species, which carries the deadly crayfish plague, creates an ecological advantage by reducing the populations of indigenous crayfish. Subsequently, the invasive females opportunistically use the available resources to enhance their fecundity, resulting in the acute growth of populations. However, the long-term competitiveness and colonisation success of O. limosus still remain in question.

  18. Silent Victims: Children Exposed to Family Violence

    ERIC Educational Resources Information Center

    Kolar, Kathryn R.; Davey, Debrynda

    2007-01-01

    Annually an estimated 3 million or more children are exposed to acts of domestic violence between adults in their homes. These children are at risk for abuse themselves as well as other immediate and long-term problems, especially if they have been exposed to repeated episodes of domestic violence. Multiple behavioral manifestations, including…

  19. Eryptosis in lead-exposed workers.

    PubMed

    Aguilar-Dorado, Itzel-Citlalli; Hernández, Gerardo; Quintanar-Escorza, Martha-Angelica; Maldonado-Vega, María; Rosas-Flores, Margarita; Calderón-Salinas, José-Víctor

    2014-12-01

    Eryptosis is a physiological phenomenon in which old and damaged erythrocytes are removed from circulation. Erythrocytes incubated with lead have exhibited major eryptosis. In the present work we found evidence of high levels of eryptosis in lead exposed workers possibly via oxidation. Blood samples were taken from 40 male workers exposed to lead (mean blood lead concentration 64.8μg/dl) and non-exposed workers (4.2μg/dl). The exposure to lead produced an intoxication characterized by 88.3% less δ-aminolevulinic acid dehydratase (δALAD) activity in lead exposed workers with respect to non-lead exposed workers. An increment of oxidation in lead exposed workers was characterized by 2.4 times higher thiobarbituric acid-reactive substance (TBARS) concentration and 32.8% lower reduced/oxidized glutathione (GSH/GSSG) ratio. Oxidative stress in erythrocytes of lead exposed workers is expressed in 192% higher free calcium concentration [Ca(2+)]i and 1.6 times higher μ-calpain activity with respect to non-lead exposed workers. The adenosine triphosphate (ATP) concentration was not significantly different between the two worker groups. No externalization of phosphatidylserine (PS) was found in non-lead exposed workers (<0.1%), but lead exposed workers showed 2.82% externalization. Lead intoxication induces eryptosis possibly through a molecular pathway that includes oxidation, depletion of reduced glutathione (GSH), increment of [Ca(2+)], μ-calpain activation and externalization of PS in erythrocytes. Identifying molecular signals that induce eryptosis in lead intoxication is necessary to understand its physiopathology and chronic complications.

  20. Eryptosis in lead-exposed workers

    SciTech Connect

    Aguilar-Dorado, Itzel-Citlalli; Hernández, Gerardo; Quintanar-Escorza, Martha-Angelica; Maldonado-Vega, María; Rosas-Flores, Margarita; Calderón-Salinas, José-Víctor

    2014-12-01

    Eryptosis is a physiological phenomenon in which old and damaged erythrocytes are removed from circulation. Erythrocytes incubated with lead have exhibited major eryptosis. In the present work we found evidence of high levels of eryptosis in lead exposed workers possibly via oxidation. Blood samples were taken from 40 male workers exposed to lead (mean blood lead concentration 64.8 μg/dl) and non-exposed workers (4.2 μg/dl). The exposure to lead produced an intoxication characterized by 88.3% less δ-aminolevulinic acid dehydratase (δALAD) activity in lead exposed workers with respect to non-lead exposed workers. An increment of oxidation in lead exposed workers was characterized by 2.4 times higher thiobarbituric acid-reactive substance (TBARS) concentration and 32.8% lower reduced/oxidized glutathione (GSH/GSSG) ratio. Oxidative stress in erythrocytes of lead exposed workers is expressed in 192% higher free calcium concentration [Ca{sup 2+}]{sub i} and 1.6 times higher μ-calpain activity with respect to non-lead exposed workers. The adenosine triphosphate (ATP) concentration was not significantly different between the two worker groups. No externalization of phosphatidylserine (PS) was found in non-lead exposed workers (< 0.1%), but lead exposed workers showed 2.82% externalization. Lead intoxication induces eryptosis possibly through a molecular pathway that includes oxidation, depletion of reduced glutathione (GSH), increment of [Ca{sup 2+}], μ-calpain activation and externalization of PS in erythrocytes. Identifying molecular signals that induce eryptosis in lead intoxication is necessary to understand its physiopathology and chronic complications. - Graphical abstract: Fig. 1. (A) Blood lead concentration (PbB) and (B) phosphatidylserine externalization on erythrocyte membranes of non-lead exposed (□) and lead exposed workers (■). Values are mean ± SD. *Significantly different (P < 0.001). - Highlights: • Erythrocytes of lead exposed workers

  1. [Observations of neurobehavior in lead exposed workers].

    PubMed

    Zhang, X Q

    1991-09-01

    A neurobehavioral test of lead-exposed workers and the correlations between test scores and certain biochemical indices was made. The results showed that the scores of digit span, mental arithmetic, block design, digit symbol, Santa-Ana dexterity, Benton visual retention and pursuit aiming of lead-exposed workers tests were significantly lower than those of control groups. The scores of Santa-Ana dexterity, block design and digit span tests of lead-exposed workers were highly negatively correlated with levels of ZPP in blood.

  2. Field observations of intraspecific agonistic behavior of two crayfish species, Orconectes rusticus and Orconectes virilis, in different habitats.

    PubMed

    Bergman, Daniel A; Moore, Paul A

    2003-08-01

    Agonistic behavior is a fundamental aspect of ecological theories on resource acquisition and sexual selection. Crustaceans are exemplary models for agonistic behavior within the laboratory, but agonistic behavior in natural habitats is often neglected. Laboratory studies do not achieve the same ecological realism as field studies. In an attempt to connect laboratory results to field data and investigate how habitat structure affects agonistic interactions, the nocturnal behavior of two crayfish species was observed by scuba diving and snorkeling in two northern Michigan lakes. Intraspecific agonistic interactions were analyzed in three habitats: two food resources-macrophytes and detritus-and one sheltered habitat. The overall observations reinforce the concept that resources influence agonistic bouts. Fights in the presence of shelters were longer and more intense, suggesting that shelters have a higher perceived value than food resources. Fights in the presence of detritus patches had higher average intensities and ended with more tailflips away from an opponent, suggesting that detritus was a more valuable food resource than macrophytes. In addition, observations of aggressive behavior within a natural setting can add validity to laboratory studies. When fights in nature are compared with laboratory fights, those in nature are shorter, less intense, and less likely to end with a tailflip, but do show the fundamental fight dynamics associated with laboratory studies. Extrinsic and intrinsic factors affect intraspecific aggression in many ways, and both should always be recognized as having the potential to alter agonistic behavior.

  3. The astrobiological mission EXPOSE-R on board of the International Space Station

    NASA Astrophysics Data System (ADS)

    Rabbow, Elke; Rettberg, Petra; Barczyk, Simon; Bohmeier, Maria; Parpart, Andre; Panitz, Corinna; Horneck, Gerda; Burfeindt, Jürgen; Molter, Ferdinand; Jaramillo, Esther; Pereira, Carlos; Weiß, Peter; Willnecker, Rainer; Demets, René; Dettmann, Jan

    2015-01-01

    EXPOSE-R flew as the second of the European Space Agency (ESA) EXPOSE multi-user facilities on the International Space Station. During the mission on the external URM-D platform of the Zvezda service module, samples of eight international astrobiology experiments selected by ESA and one Russian guest experiment were exposed to low Earth orbit space parameters from March 10th, 2009 to January 21st, 2011. EXPOSE-R accommodated a total of 1220 samples for exposure to selected space conditions and combinations, including space vacuum, temperature cycles through 273 K, cosmic radiation, solar electromagnetic radiation at >110, >170 or >200 nm at various fluences up to GJ m-2. Samples ranged from chemical compounds via unicellular organisms and multicellular mosquito larvae and seeds to passive radiation dosimeters. Additionally, one active radiation measurement instrument was accommodated on EXPOSE-R and commanded from ground in accordance with the facility itself. Data on ultraviolet radiation, cosmic radiation and temperature were measured every 10 s and downlinked by telemetry and data carrier every few months. The EXPOSE-R trays and samples returned to Earth on March 9th, 2011 with Shuttle flight, Space Transportation System (STS)-133/ULF 5, Discovery, after successful total mission duration of 27 months in space. The samples were analysed in the individual investigators laboratories. A parallel Mission Ground Reference experiment was performed on ground with a parallel set of hardware and samples under simulated space conditions following to the data transmitted from the flight mission.

  4. Hormonal Perturbations in Occupationally Exposed Nickel Workers

    PubMed Central

    Beshir, Safia; Ibrahim, Khadiga Salah; Shaheen, Weam; Shahy, Eman M.

    2016-01-01

    BACKGROUND: Nickel exposure is recognized as an endocrine disruptor because of its adverse effects on reproduction. AIM: This study was designed to investigate the possible testiculo-hormonal perturbations on workers occupationally exposed to nickel and to assess its effects on human male sexual function. METHODS: Cross-sectional comparative study, comprising 105 electroplating male non-smoker, non-alcoholic workers exposed to soluble nickel and 60 controls was done. Serum luteinizing hormone, follicle stimulating hormone, testosterone levels and urinary nickel concentrations were determined for the studied groups. RESULTS: Serum luteinizing hormone, follicle stimulating hormone, urinary nickel and the simultaneous incidence of more than one sexual disorder were significantly higher in the exposed workers compared to controls. The occurrence of various types of sexual disorders (decreased libido, impotence and premature ejaculation) in the exposed workers was 9.5, 5.1 and 4.4 folds respectively than the controls. CONCLUSIONS: Exposure to nickel produces possible testiculo-hormonal perturbations in those exposed workers. PMID:27335607

  5. The Expose-R2 mission: astrobiology and astrochemistry in low Earth orbit

    NASA Astrophysics Data System (ADS)

    Demets, René

    EXPOSE is an exposure platform developed by ESA which permits scientists to install test samples for 1 to 2 years at the outer surface of the ISS. In that way, the impact of the open space environment on biological and biochemical sample materials can be explored. This environment, featuring full-spectrum solar light, near-vacuum, cosmic radiation, wide temperature variations and near-weightlessness, is impossible to reproduce in its entirety in the lab. As such, EXPOSE offers astrochemists and astrobiologists a chance to acquire novel scientific data. Astrochemists are interested in Low Earth Orbit conditions due to the fact that photochemistry in space is quite different from photochemistry on Earth, where the high-energy UV compounds of the solar spectrum are filtered away by our atmosphere. As for the astro biologists, EXPOSE offers an attractive opportunity to expand earlier results obtained during short-duration LEO flights, which have shown that particular microbes and, amazingly, even some multi-cellular macroscopic organisms were able to cope with a two-week exposure to space. The open space environment, often described as harsh and hostile, can apparently be tolerated by some robust inhabitants of our Earth - unprotected, in the absence of a space suit! The first mission of EXPOSE, as an external payload on the European Columbus module, happened during 2008-2009 with the test samples provided by five separate research teams. Three additional teams were involved in the monitoring of space environment. The results were published collectively in 2012 in a special issue of the monthly journal Astrobiology. Several organisms survived, having spent 1.5 years in space. The second mission was called EXPOSE-R, the R referring to ‘Russian segment’, the location where the EXPOSE instrument was installed this time. The EXPOSE-R mission took place in 2009-2011, ten science teams were involved. The publication of the results, again as a collection, is currently in

  6. Metabolomic analysis of sun exposed skin.

    PubMed

    Randhawa, Manpreet; Southall, Michael; Samaras, Samantha Tucker

    2013-08-01

    It is very well known that exposure of skin to sun chronically accelerates the mechanism of aging as well as making it more susceptible toward skin cancer. This aspect of aging has been studied very well through genomics and proteomics tools. In this study we have used a metabolomic approach for the first time to determine the differences in the metabolome from full thickness skin biopsies from sun exposed and sun protected sites. We have primarily investigated the energy metabolism and the oxidative pathway in sun exposed skin. Biochemical pathway analysis revealed that energy metabolism in photoexposed skin is predominantly anaerobic. The study also validated the increased oxidative stress in skin.

  7. Autophagy in ethanol-exposed liver disease.

    PubMed

    Wang, Li-Ren; Zhu, Gui-Qi; Shi, Ke-Qing; Braddock, Martin; Zheng, Ming-Hua

    2015-01-01

    Ethanol metabolism in hepatocytes causes the generation of reactive oxygen species, endoplasmic reticulum stress and alterations in mitochondrial energy and REDOX metabolism. In ethanol-exposed liver disease, autophagy not only acts as a cleanser to remove damaged organelles and cytosolic components, but also selectively clears specific targets such as lipid droplets and damaged mitochondria. Moreover, ethanol appears to play a role in protecting hepatocytes from apoptosis at certain concentrations. This article describes the evidence, function and potential mechanism of autophagy in ethanol-exposed liver disease and the controversy surrounding the effects of ethanol on autophagy.

  8. Lipid abnormalities in workers exposed to dioxin.

    PubMed Central

    Martin, J V

    1984-01-01

    Ten years after an incident in which workers were exposed to tetrachlorodibenzodioxin (TCDD) a controlled biochemical study showed statistically significant increases in the serum cholesterol and triglyceride concentrations of workers both with and without chloracne. Urinary excretion of D-glucaric acid was significantly higher for all workers. PMID:6232943

  9. Rural Canadian Youth Exposed to Physical Violence

    ERIC Educational Resources Information Center

    Laye, Adele M.; Mykota, David B.

    2014-01-01

    Exposure to physical violence is an unfortunate reality for many Canadian youth as it is associated with numerous negative psychosocial effects. The study aims to assist in understanding resilience in rural Canadian youth exposed to physical violence. This is accomplished by identifying the importance of protective factors, as measured by the…

  10. Cocaine Babies: Florida's Substance-Exposed Youth.

    ERIC Educational Resources Information Center

    Harpring, Jayme

    This report is designed to provide Florida's school personnel with assistance in working with students prenatally exposed to cocaine or other toxic substances. The report offers background data, practical strategies for teaching and learning, and resources for networking. The first chapter outlines statistics on the incidence of the problem of…

  11. Interviews with Children Exposed to Violence

    ERIC Educational Resources Information Center

    Eriksson, Maria; Nasman, Elisabet

    2012-01-01

    The aim of this article is to show how research practices may simultaneously follow principles of children's citizenship rights to participation and principles of protection and support when children exposed to violence are informants. The article focuses upon organisation of interview processes and interactions between adult researchers and child…

  12. Exposing the Mathematical Wizard: Approximating Trigonometric Functions

    ERIC Educational Resources Information Center

    Gordon, Sheldon P.

    2011-01-01

    For almost all students, what happens when they push buttons on their calculators is essentially magic, and the techniques used are seemingly pure wizardry. In this article, the author draws back the curtain to expose some of the mathematics behind computational wizardry and introduces some fundamental ideas that are accessible to precalculus…

  13. Expose Mechanical Engineering Students to Biomechanics Topics

    ERIC Educational Resources Information Center

    Shen, Hui

    2011-01-01

    To adapt the focus of engineering education to emerging new industries and technologies nationwide and in the local area, a biomechanics module has been developed and incorporated into a mechanical engineering technical elective course to expose mechanical engineering students at ONU (Ohio Northern University) to the biomedical engineering topics.…

  14. Mitochondrial DNA deletion percentage in sun exposed and non sun exposed skin.

    PubMed

    Powers, Julia M; Murphy, Gillian; Ralph, Nikki; O'Gorman, Susan M; Murphy, James E J

    2016-12-01

    The percentages of mitochondrial genomes carrying the mtDNA(3895) and the mtDNA(4977) (common) deletion were quantified in sun exposed and non sun exposed skin biopsies, for five cohorts of patients varying either in sun exposure profile, age or skin cancer status. Non-melanoma skin cancer diagnoses are rising in Ireland and worldwide [12] but most risk prediction is based on subjective visual estimations of sun exposure history. A quantitative objective test for pre-neoplastic markers may result in better adherence to sun protective behaviours. Mitochondrial DNA (mtDNA) is known to be subject to the loss of a significant proportion of specific sections of genetic code due to exposure to ultraviolet light in sunlight. Although one such deletion has been deemed more sensitive, another, called the mtDNA(4977) or common deletion, has proved to be a more useful indicator of possible risk in this study. Quantitative molecular analysis was carried out to determine the percentage of genomes carrying the deletion using non sun exposed and sun exposed skin biopsies in cohorts of patients with high or low sun exposure profiles and two high exposure groups undergoing treatment for NMSC. Results indicate that mtDNA deletions correlate to sun exposure; in groups with high sun exposure habits a significant increase in deletion number in exposed over non sun exposed skin occurred. An increase in deletion percentage was also seen in older cohorts compared to the younger group. The mtDNA(3895) deletion was detected in small amounts in exposed skin of many patients, the mtDNA(4977) common deletion, although present to some extent in non sun exposed skin, is suggested to be the more reliable and easily detected marker. In all cohorts except the younger group with relatively lower sun exposure, the mtDNA(4977) deletion was more frequent in sun exposed skin samples compared to non-sun exposed skin.

  15. Reactions of latent prints exposed to blood.

    PubMed

    Praska, Nicole; Langenburg, Glenn

    2013-01-10

    We explored whether an undeveloped latent print (fingermark) exposed to blood and later developed by enhancement with blood reagents such as amido black (AB) or leucocrystal violet (LCV) could appear as a genuine blood mark. We examined three different experimental conditions. In Experiment I, fingermark residue only was tested, as a control to confirm that fingermark residue alone does not react with the blood reagents AB and LCV. Experiment II investigated whether latent fingermarks exposed to blood dilutions could be treated with AB or LCV and subsequently appear as a genuine blood mark enhanced with AB or LCV. Experiment III tested whether latent fingermarks exposed to whole blood could be processed with AB or LCV and subsequently appear as a genuine blood mark enhanced with AB or LCV. The present study found that indeed, fingermark residue alone does not react with the blood reagents AB and LCV. In Experiment II, an interaction occurred between the fingermark residue and the diluted blood that caused the ridges to appear a red color. In the present study, this interaction is called a faux blood mark. While the faux blood mark phenomenon occurred most often following exposure to diluted blood, it did not occur consistently, and a predictable pattern could not be established. However, the reaction occurred more frequently following extended fingermark residue drying times. Faux blood marks are distinguishable from genuine blood marks prior to enhancement with blood reagents. Following treatment with blood reagents, it became increasingly difficult to determine whether the enhanced mark was a genuine blood print or a latent fingermark exposed to diluted blood. Latent fingermarks exposed to whole blood often resulted in a void prior to enhancement, but following treatment with blood reagents, were difficult to distinguish from a genuine blood mark enhanced with blood reagents.

  16. Surface contamination on LDEF exposed materials

    NASA Technical Reports Server (NTRS)

    Hemminger, Carol S.

    1992-01-01

    X-ray photoelectron spectroscopy (XPS) has been used to study the surface composition and chemistry of Long Duration Exposure Facility (LDEF) exposed materials including silvered Teflon (Ag/FEP), Kapton, S13GLO paint, quartz crystal monitors (QCM's), carbon fiber/organic matrix composites, and carbon fiber/Al Alloy composites. In each set of samples, silicones were the major contributors to the molecular film accumulated on the LDEF exposed surfaces. All surfaces analyzed have been contaminated with Si, O, and C; most have low levels (less than 1 atom percent) of N, S, and F. Occasionally observed contaminants included Cl, Na, K, P, and various metals. Orange/brown discoloration observed near vent slots in some Ag/FEP blankets were higher in carbon, sulfur, and nitrogen relative to other contamination types. The source of contamination has not been identified, but amine/amide functionalities were detected. It is probable that this same source of contamination account for the low levels of sulfur and nitrogen observed on most LDEF exposed surfaces. XPS, which probes 50 to 100 A in depth, detected the major sample components underneath the contaminant film in every analysis. This probably indicates that the contaminant overlayer is patchy, with significant areas covered by less that 100 A of molecular film. Energy dispersive x-ray spectroscopy (EDS) of LDEF exposed surfaces during secondary electron microscopy (SEM) of the samples confirmed contamination of the surfaces with Si and O. In general, particulates were not observed to develop from the contaminant overlayer on the exposed LDEF material surfaces. However, many SiO2 submicron particles were seen on a masked edge of an Ag/FEP blanket. In some cases such as the carbon fiber/organic matrix composites, interpretation of the contamination data was hindered by the lack of good laboratory controls. Examination of laboratory controls for the carbon fiber/Al alloy composites showed that preflight contamination was

  17. The EXPOSE-R Experiment ROSE-3 SPORES in artificial meteorites

    NASA Astrophysics Data System (ADS)

    Panitz, C.; Horneck, G.; Rabbow, E.; Rettberg, P.; Reitz, G.

    2011-10-01

    In the conducted experiment, spores of bacteria, fungi and ferns, especially adapted to survive extreme conditions, were either solely or embedded in artificial meteorites exposed to space environment in the ESA facility EXPOSE-R for 22 months (10.03.2009-21.02.2011). The experiment will provide experimental clues to the question whether meteorite material offers enough protection against the harsh environment of space for spores to survive a long-term stay in space. This question has received increased attention since the discovery of Martian meteorites has provided evidence that rocks can be transported from one planet to another in our solar

  18. Children exposed to war/terrorism.

    PubMed

    Shaw, Jon A

    2003-12-01

    This paper reviews the prevalence of psychological morbidities in children who have been exposed to war-related traumas or terrorism as well as the diversity of war-related casualties and their associated psychological responses. The psychological responses to war-related stressors are categorized as (1) little or no reaction, (2) acute emotional and behavioral effects, and (3) long-term effects. Specific categories of war-related casualties discussed include refugee status, traumatic bereavement, effects of parental absence, and child soldiers. Psychological responses associated with terrorism and bioterrorism are presented. Lastly, mediators of the psychological response to war-related stressors are discussed, to include exposure effects, gender effects, parental, family and social factors, and child-specific factors. Children exposed to war-related stressors experience a spectrum of psychological morbidities including posttraumatic stress symptomatology, mood disorders, externalizing and disruptive behaviors, and somatic symptoms determined by exposure dose effect. Specific questions for future research are identified.

  19. Viability of bacterial spores exposed to hydrazine

    NASA Astrophysics Data System (ADS)

    Schubert, W.; Plett, G.; Yavrouian, A.; Barengoltz, J.

    2008-09-01

    For the purposes of planetary protection, a series of experiments were performed to answer a long-standing question about the potential of bacterial contamination of interplanetary spacecraft from liquid hydrazine. Spores of Bacillus atrophaeus (ATCC No. 9372, also known as Bacillus subtilis var. niger, and BSN) were exposed to hydrazine and survivors were enumerated using the NASA standard planetary protection pour plate assay. Results indicate that bulk hydrazine rocket propellant may be considered free of living bacterial cells for planetary protection compliance.

  20. Genetic Alterations in Pesticide Exposed Bolivian Farmers

    PubMed Central

    Jørs, Erik; Gonzáles, Ana Rosa; Ascarrunz, Maria Eugenia; Tirado, Noemi; Takahashi, Catharina; Lafuente, Erika; Dos Santos, Raquel A; Bailon, Natalia; Cervantes, Rafael; O, Huici; Bælum, Jesper; Lander., Flemming

    2007-01-01

    Background Pesticides are of concern in Bolivia because of increasing use. Frequent intoxications have been demonstrated due to use of very toxic pesticides, insufficient control of distribution and sale and little knowledge among farmers of protective measures and hygienic procedures. Method Questionnaires were applied and blood tests taken from 81 volunteers from La Paz County, of whom 48 were pesticide exposed farmers and 33 non-exposed controls. Sixty males and 21 females participated with a mean age of 37.3 years (range 17–76). Data of exposure and possible genetic damage were collected and evaluated by well known statistical methods, controlling for relevant confounders. To measure genetic damage chromosomal aberrations and the comet assay analysis were performed. Results Pesticide exposed farmers had a higher degree of genetic damage compared to the control group. The number of chromosomal aberrations increased with the intensity of pesticide exposure. Females had a lower number of chromosomal aberrations than males, and people living at altitudes above 2500 metres seemed to exhibit more DNA damage measured by the comet assay. Conclusions Bolivian farmers showed signs of genotoxic damage, probably related to exposure to pesticides. Due to the potentially negative long term health effects of genetic damage on reproduction and the development of cancer, preventive measures are recommended. Effective control with imports and sales, banning of the most toxic pesticides, education and information are possible measures, which could help preventing the negative effects of pesticides on human health and the environment. PMID:19662224

  1. Mortality patterns among workers exposed to acrylamide

    SciTech Connect

    Collins, J.J.; Swaen, G.M.; Marsh, G.M.; Utidjian, H.M.; Caporossi, J.C.; Lucas, L.J. )

    1989-07-01

    A cohort of 8854 men, 2293 of whom were exposed to acrylamide, was examined from 1925 to 1983 for mortality. This cohort consisted of four plant populations in two countries: the United States and The Netherlands. No statistically significant excess of all-cause or cause-specific mortality was found among acrylamide workers. Analysis by acrylamide exposure levels showed no trend of increased risk of mortality from several cancer sites. These results do not support the hypothesis that acrylamide is a human carcinogen.

  2. The PUR Experiment on the EXPOSE-R facility: biological dosimetry of solar extraterrestrial UV radiation

    NASA Astrophysics Data System (ADS)

    Bérces, A.; Egyeki, M.; Fekete, A.; Horneck, G.; Kovács, G.; Panitz, C.

    2015-01-01

    The aim of our experiment Phage and Uracil Response was to extend the use of bacteriophage T7 and uracil biological dosimeters for measuring the biologically effective ultraviolet (UV) dose in the harsh extraterrestrial radiation conditions. The biological detectors were exposed in vacuum-tightly cases in the European Space Agency (ESA) astrobiological exposure facility attached to the external platform of Zvezda (EXPOSE-R). EXPOSE-R took off to the International Space Station (ISS) in November 2008 and was installed on the External platform of the Russian module Zvezda of the ISS in March 2009. Our goal was to determine the dose-effect relation for the formation of photoproducts (i.e. damage to phage DNA and uracil, respectively). The extraterrestrial solar UV radiation ranges over the whole spectrum from vacuum-UV (λ<200 nm) to UVA (315 nm<λ<400 nm), which causes photolesions (photoproducts) in the nucleic acids/their components either by photoionization or excitation. However, these wavelengths cause not only photolesions but in a wavelength-dependent efficiency the reversion of some photolesions, too. Our biological detectors measured in situ conditions the resultant of both reactions induced by the extraterrestrial UV radiation. From this aspect the role of the photoreversion in the extension of the biological UV dosimetry are discussed.

  3. Dynamic properties of ultraviolet-exposed polyurea

    NASA Astrophysics Data System (ADS)

    Youssef, George; Whitten, Ian

    2016-11-01

    Polyurea is used in military and civilian applications, where exposure to the sun in long durations is imminent. Extended exposure to ultraviolet radiation from the sun can deteriorate its mechanical performance to suboptimal levels. This study reports on the dynamic mechanical properties of polyurea as a function of ultraviolet radiation exposure duration. Six sets of samples were continuously exposed to ultraviolet radiation for different durations up to 18 weeks. Control samples were also tested that did not receive ultraviolet exposure. The dynamic properties were measured using a dynamic mechanical analyzer. Exposed samples exhibited significant color changes from transparent yellow to opaque tan after 18 weeks of exposure. Changes of color were observed as early as 3 weeks of exposure. The dynamic properties showed an initial increase in the dynamic modulus after 3 weeks of exposure, with no further significant change in the stiffness thereafter. The ultraviolet exposure had a significant impact at relatively short loading times or low temperature, for example, up to 6 decades of time. As loading time increases or polyurea operates at high temperature, the effect of ultraviolet exposure and temperature on the performance become highly coupled.

  4. Expose hidden failures to prevent cascading outages

    SciTech Connect

    Phadke, A.G.; Thorp, J.S.

    1996-07-01

    This article describes how to identify lines and buses that present the greatest hazard to system reliability, and add digital equipment to supervise and control hidden failures of the associated relays. Major blackouts are rare events, but their impact can be catastrophic. A study of significant disturbances reported by NERC in the period from 1984 through 1988 indicates that protective relays are involved in one way or another in 75% of major disturbances. A common scenario is that the relay has an undetected (hidden) defect that was exposed due to the conditions created by other disturbances. For example, near-by faults, overloads, or reverse power flows expose the defective relay and cause a false trip, which exacerbates the situation. Given the importance of hidden failure modes in traditional relaying systems, intervention by computer-based rational control schemes is proposed in this article. Relays with high-vulnerability indices can be identified, and their vulnerable functions and failure modes identified. Countermeasures to reduce or eliminate the likelihood of the hidden failure of key relays can be provided.

  5. Endometriosis among Women Exposed to Polybrominated Biphenyls

    PubMed Central

    Hoffman, Caroline S.; Small, Chanley M.; Blanck, Heidi Michels; Tolbert, Paige; Rubin, Carol; Marcus, Michele

    2007-01-01

    Purpose We examined the association between endometriosis and exposure to polybrominated biphenyls (PBBs) and polychlorinated biphenyls (PCBs) among women inadvertently exposed to PBBs in 1973. Methods Serum PBB and PCB were measured in the late 1970s. Women self-reported endometriosis at interview in 1997. We constructed Cox models to estimate the relative incidence of endometriosis in relation to PBB and PCB levels. Results Seventy-nine of 943 women (9%) reported endometriosis. Compared to women with low PBB exposure (≤ 1 parts per billion [ppb]), women with moderate PBB (1–4 ppb) (hazard ratio [HR] = 0.72; 95% confidence interval [CI], 0.39–1.31) and high PBB (≥ 4 ppb) (HR = 0.90; 95% CI, 0.51–1.59) exposure did not have increased incidence of endometriosis. Increased incidence of endometriosis was suggested among women exposed to moderate PCB (5–8 ppb) (HR = 1.67; 95% CI, 0.91–3.10) and high PCB (≥ 8 ppb) (HR = 1.68; 95% CI, 0.95–2.98) levels compared to low PCB exposure (≤ 5 ppb). Conclusions Our study does not support an association between PBB exposure and endometriosis. Findings for serum PCB level are consistent with an emerging body of literature suggesting an association between PCB exposure and endometriosis. PMID:17448678

  6. Cancer occurrence among workers exposed to acrylonitrile.

    PubMed

    Rothman, K J

    1994-10-01

    A MEDLINE search identified 12 published epidemiologic studies that have reported incidence or mortality experience among workers exposed to acrylonitrile. Many of the studies contain scanty descriptions of subject ascertainment, and most do not have good information on exposure assessment. Many also may have suffered from incomplete follow-up, as evinced by an overall deficit in the number of deaths observed, compared with the number expected from general population mortality rates. Such problems are not unique to studies on acrylonitrile, and to some extent they reflect the difficulties of conducting retrospective cohort studies. Despite these drawbacks, a simplified meta-analysis of the mortality experience reported for these cohorts revealed little evidence for carcinogenicity. Approximately the same number of cancer deaths was observed as was expected according to general population mortality rates (standardized mortality ratio 1.03, 90% confidence interval 0.92-1.15). The combined information from these studies is insufficient to support confidence about a lack of carcinogenicity at all sites. Nevertheless, despite the flaws in some of the individual studies, the summarized findings offer reassurance that workers exposed to acrylonitrile face no striking increases in mortality for all cancers or for respiratory cancer.

  7. Erythrocyte survival in sheep exposed to ozone

    SciTech Connect

    Moore, G.S.; Calabrese, E.J.; Labato, F.J.

    1981-07-01

    Erythrocyte survival studies in the Dorset ewe using chromium 51 were performed. The purpose of the study was to determine if ozone exposure produces decreased cell survival which may be the result of premature erythrocyte aging. This strain of sheep has an erythrocyte glucose-6-phosphate dehydrogenase (G6PD) activity that is very low, being comparable to human A-variants with G6PD deficiency. Ozone exposure may produce hemolytic effects in G6PD deficients more readily than in erythrocytes with normal activity. A decrease in hematocrit was observed in the ozone exposed groups. With respect to red cell destruction, ozone does not appear to act immediately, but rather there appears to be a delayed effect. At 0.25 ppM ozone, the group reached the 50% remaining level an average of 1 day sooner than the control group. There was no significant difference between control and exposed groups at the 0.50 ppM and 0.70 ppM levels. Also, the results demonstrate a net decrease in hematocrit which is greater for 0.25 ppM ozone than any other exposure level. (RJC)

  8. Blood morphine levels in naltrexone-exposed compared to non-naltrexone-exposed fatal heroin overdoses.

    PubMed

    Arnold-Reed, Diane E; Hulse, Gary K; Hansson, Robert C; Murray, Sean D; O'Neil, George; Basso, Maria R; Holman, C D'Arcy J

    2003-09-01

    The aim of this study was to investigate the association between prior exposure to naltrexone and increased risk of fatal heroin overdose using a review of toxicology reports for heroin-related fatalities between July 1997 to August 1999 for two groups: those treated with oral naltrexone and those who were not treated. Additional information for the oral naltrexone group was obtained from clinic files. Naltrexone-treated deaths were identified from the patient database at the Australian Medical Procedures Research Foundation (AMPRF), Perth, Western Australia (WA) through the Western Australian Department of Health, Data Linkage Project. Non-treated cases were identified from the database at the Forensic Science Laboratory, State Chemistry Centre (WA). We identified and investigated blood morphine concentrations following 21 fatal heroin overdoses with prior exposure to naltrexone and in 71 non-naltrexone-exposed cases over the same time period. The proportion of deaths where heroin use was a major contributing factor was little different in the non-naltrexone compared to the naltrexone-exposed group. Furthermore, in 'acute opiate toxicity' deaths, blood morphine levels were lower in non-naltrexone-exposed compared with naltrexone-exposed cases. Although there was a higher number of deaths designated as rapid (i.e. occurring within 20 minutes) in the naltrexone-exposed (89%) compared with the non-exposed group (72%) this was not statistically significant. Other drug use in relation to heroin-related fatalities is discussed. Findings do not support the hypothesis that prior exposure to naltrexone increases sensitivity to heroin toxicity.

  9. Normal Modes Expose Active Sites in Enzymes

    PubMed Central

    Glantz-Gashai, Yitav; Samson, Abraham O.

    2016-01-01

    Accurate prediction of active sites is an important tool in bioinformatics. Here we present an improved structure based technique to expose active sites that is based on large changes of solvent accessibility accompanying normal mode dynamics. The technique which detects EXPOsure of active SITes through normal modEs is named EXPOSITE. The technique is trained using a small 133 enzyme dataset and tested using a large 845 enzyme dataset, both with known active site residues. EXPOSITE is also tested in a benchmark protein ligand dataset (PLD) comprising 48 proteins with and without bound ligands. EXPOSITE is shown to successfully locate the active site in most instances, and is found to be more accurate than other structure-based techniques. Interestingly, in several instances, the active site does not correspond to the largest pocket. EXPOSITE is advantageous due to its high precision and paves the way for structure based prediction of active site in enzymes. PMID:28002427

  10. Plasma prolactin concentrations in lead exposed workers.

    PubMed

    Govoni, S; Battaini, F; Fernicola, C; Castelletti, L; Trabucchi, M

    1987-01-01

    Plasma Prolactin (Prl) Zinc protoporphyrin (Zpp) and blood lead concentrations (PbB) were measured in 76 exposed male workers. All of them were employed in small (not more than 30 persons) pewter factories and were randomly selected from those regularly controlled by the National Health Service, Occupational Health Unit of Brescia (USSL 41). Although all plasma Prl values were within the normal range, the mean value of the subgroup having Zpp and PbB higher than 40 micrograms/dl was significantly higher (+47%) than that observed in the group of workers having Zpp and PbB less than 40 micrograms/dl. The data indicate the possibility of a lead-induced Prl secretion dysfunction, probably mediated by a decrease in dopaminergic inhibitory control.

  11. Dust release from surfaces exposed to plasma

    SciTech Connect

    Flanagan, T. M.; Goree, J.

    2006-12-15

    Micrometer-sized particles adhered to a surface can be released when exposed to plasma. In an experiment with a glass surface coated with lunar-simulant dust, it was found that particle release requires exposure to both plasma and an electron beam. The dust release rate diminishes almost exponentially in time, which is consistent with a random process. As proposed here, charges of particles adhered to the surface fluctuate. These charges experience a fluctuating electric force that occasionally overcomes the adhesive van der Waals force, causing particle release. The release rate increases with plasma density, so that plasma cleaning is feasible at high plasma densities. Applications of this cleaning include controlling particulate contamination in semiconductor manufacturing, dust mitigation in the exploration of the moon and Mars, and dusty plasmas.

  12. Viability of bacterial spores exposed to hydrazine

    NASA Astrophysics Data System (ADS)

    Schubert, W.; Plett, G.; Yavrouian, A.; Barengoltz, J.

    For the purposes of planetary protection a series of experiments were performed to answer a long-standing question about the potential of bacterial contamination of interplanetary spacecraft from liquid hydrazine Spores of Bacillus atrophaeus ATCC No 9372 also known as Bacillus subtilis var niger and BSN were exposed to hydrazine for various durations Then the survivors were enumerated using the NASA standard planetary protection pour plate assay It is important to note that in these experiments the hydrazine was removed prior to the assay This eliminated the possibility that the presence of hydrazine rather than a prior exposure was inhibiting germination and or reproduction Populations of 10 6 spores were eliminated within 30 minutes These results indicate that bulk hydrazine rocket propellant may be considered free of living bacterial cells for planetary protection compliance

  13. Population exposed to landslide risk in Italy

    NASA Astrophysics Data System (ADS)

    Trigila, Alessandro; Iadanza, Carla; Munafò, Michele; Baiocco, Fabio; Marinosci, Ines; Chiocchini, Raffaella; Mugnoli, Stefano

    2013-04-01

    Italy is one of the European countries most affected by landslides counting over 486,000 mass movements with a total area of 20,700 square kilometres equal to 6.9% of the national territory. Moreover Italy is a densely urbanized country: 8101 municipalities, about 200 inhabitants per sq. km, 16,000 km of rail network and 180,000 km of road network. Landslides caused more than 5000 fatalities in the last century and considerable damage to urban areas, transport infrastructure and facilities, environmental and cultural heritage. The aim of this work is to estimate the population exposed to landslide risk in Italy. The input data are: the Italian Landslide Inventory, the Italian Population Census data and the high-resolution Artificial surfaces-Imperviousness Layer (Geoland2). The Italian Landslide Inventory (Progetto IFFI) realised by ISPRA (Italian National Institute for Environmental Protection and Research) and the Regions and Self-governing Provinces, identifies landslides occurred in the national territory in accordance with standardized methods and using a detailed landslide mapping (1:10,000 scale). The 14th Population Census, made by ISTAT (Italian National Institute of Statistics) in 2001, contains data of resident population for the 382,534 census tracts in which Italy is divided. The pan-European high-resolution (HR) Artificial surfaces-Imperviousness Layer, realized using remote sensing data within the GMES initiative (Global Monitoring for Environment and Security) by European Commission and European Space Agency, contains the degree of imperviousness (between 0 and 100%). GIS overlay of this information layer (20 x 20 m grid) with census tracts has allowed the spatialization of population within urban settlements of each census tract. This methodology has been particularly useful in the case of rural census tracts characterized by large surface area and low population density. The methodology could be also applied to estimate the population exposed to

  14. Mortality of aerospace workers exposed to trichloroethylene.

    PubMed

    Morgan, R W; Kelsh, M A; Zhao, K; Heringer, S

    1998-07-01

    We measured mortality rates in a cohort of 20,508 aerospace workers who were followed up over the period 1950-1993. A total of 4,733 workers had occupational exposure to trichloroethylene. In addition, trichloroethylene was present in some of the washing and drinking water used at the work site. We developed a job-exposure matrix to classify all jobs by trichloroethylene exposure levels into four categories ranging from "none" to "high" exposure. We calculated standardized mortality ratios for the entire cohort and the trichloroethylene exposed subcohort. In the standardized mortality ratio analyses, we observed a consistent elevation for nonmalignant respiratory disease, which we attribute primarily to the higher background rates of respiratory disease in this region. We also compared trichloroethylene-exposed workers with workers in the "low" and "none" exposure categories. Mortality rate ratios for nonmalignant respiratory disease were near or less than 1.00 for trichloroethylene exposure groups. We observed elevated rare ratios for ovarian cancer among those with peak exposure at medium and high levels] relative risk (RR) = 2.74; 95% confidence interval (CI) = 0.84-8.99] and among women with high cumulative exposure (RR = 7.09; 95% CI = 2.14-23.54). Among those with peak exposures at medium and high levels, we observed slightly elevated rate ratios for cancers of the kidney (RR = 1.89; 95% CI = 0.85-4.23), bladder (RR = 1.41; 95% CI = 0.52-3.81), and prostate (RR = 1.47; 95% CI = 0.85-2.55). Our findings do not indicate an association between trichloroethylene exposure and respiratory cancer, liver cancer, leukemia or lymphoma, or all cancers combined.

  15. First results of the ORGANIC experiment on EXPOSE-R on the ISS

    NASA Astrophysics Data System (ADS)

    Bryson, K. L.; Salama, F.; Elsaesser, A.; Peeters, Z.; Ricco, A. J.; Foing, B. H.

    2015-01-01

    The ORGANIC experiment on EXPOSE-R spent 682 days outside the International Space Station, providing continuous exposure to the cosmic-, solar- and trapped-particle radiation background for fourteen samples: 11 polycyclic aromatic hydrocarbons (PAHs) and three fullerenes. The thin films of the ORGANIC experiment received, during space exposure, an irradiation dose of the order of 14 000 MJ m-2 over 2900 h of unshadowed solar illumination. Extensive analyses were performed on the returned samples and the results compared to ground control measurements. Analytical studies of the returned samples included spectral measurements from the vacuum ultraviolet to the infrared range and time-of-flight secondary ion mass spectrometry. Limited spectral changes were observed in most cases pointing to the stability of PAHs and fullerenes under space exposure conditions. Furthermore, the results of these experiments confirm the known trend in the stability of PAH species according to molecular structure: compact PAHs are more stable than non-compact PAHs, which are themselves more stable than PAHs containing heteroatoms, the last category being the most prone to degradation in the space environment. We estimate a depletion rate of the order of 85 +/- 5% over the 17 equivalent weeks of continuous unshadowed solar exposure in the most extreme case tetracene (smallest, non-compact PAH sample). The insignificant spectral changes (below 10%) measured for solid films of large or compact PAHs and fullerenes indicate a high stability under the range of space exposure conditions investigated on EXPOSE-R.

  16. 9 CFR 78.23 - Brucellosis exposed bison.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Brucellosis exposed bison. 78.23... Restrictions on Interstate Movement of Bison Because of Brucellosis § 78.23 Brucellosis exposed bison. Brucellosis exposed bison may be moved interstate only as follows: (a) Movement to recognized...

  17. 9 CFR 78.23 - Brucellosis exposed bison.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Brucellosis exposed bison. 78.23... Restrictions on Interstate Movement of Bison Because of Brucellosis § 78.23 Brucellosis exposed bison. Brucellosis exposed bison may be moved interstate only as follows: (a) Movement to recognized...

  18. 9 CFR 78.23 - Brucellosis exposed bison.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Brucellosis exposed bison. 78.23... Restrictions on Interstate Movement of Bison Because of Brucellosis § 78.23 Brucellosis exposed bison. Brucellosis exposed bison may be moved interstate only as follows: (a) Movement to recognized...

  19. 9 CFR 78.23 - Brucellosis exposed bison.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Brucellosis exposed bison. 78.23... Restrictions on Interstate Movement of Bison Because of Brucellosis § 78.23 Brucellosis exposed bison. Brucellosis exposed bison may be moved interstate only as follows: (a) Movement to recognized...

  20. 9 CFR 78.32 - Brucellosis exposed swine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Brucellosis exposed swine. 78.32... Restrictions on Interstate Movement of Swine Because of Brucellosis § 78.32 Brucellosis exposed swine. (a) Brucellosis exposed swine may be moved interstate only if accompanied by a permit and only for...

  1. 9 CFR 78.32 - Brucellosis exposed swine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Brucellosis exposed swine. 78.32... Restrictions on Interstate Movement of Swine Because of Brucellosis § 78.32 Brucellosis exposed swine. (a) Brucellosis exposed swine may be moved interstate only if accompanied by a permit and only for...

  2. 9 CFR 78.32 - Brucellosis exposed swine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Brucellosis exposed swine. 78.32... Restrictions on Interstate Movement of Swine Because of Brucellosis § 78.32 Brucellosis exposed swine. (a) Brucellosis exposed swine may be moved interstate only if accompanied by a permit and only for...

  3. Post-exposed fiber Bragg gratings

    NASA Astrophysics Data System (ADS)

    Miller, Gary A.

    This thesis explains the development and characterization of a novel technique to fabricate weak fiber Bragg gratings for highly specific multi-element sensor arrays. This method, termed the "rescan technique," involves re-exposing a local region of a grating to fringeless ultraviolet light to "trim" unwanted portions of the reflection spectrum. The spectral effects that result from a rescan can only be adequately described by inventing the concept of a three-dimensional index growth surface, where induced index is a function of both the writing intensity and the exposure time. Using this information, it is possible to predict the spectral response of a rescanned grating using a numerical model. For our model, we have modified the piecewise-uniform approach to include coefficients within the coupled-mode formulism that imitate the same scattering properties as the actual grating. By taking high accuracy measurements of the refractive index change in germanosilicate fiber, we have created the necessary 3D map of photoinduced index to accurately model gratings and their post-exposure spectra. We will also demonstrate that optical fiber exhibits what we call "exposure history"; the final index change in a region depends on the previous exposures conditions.

  4. Cancer incidence among creosote-exposed workers.

    PubMed

    Karlehagen, S; Andersen, A; Ohlson, C G

    1992-02-01

    Cancer incidence was studied among 922 creosote-exposed impregnators at 13 plants in Sweden and Norway. The subjects had been impregnating wood (eg, railroad cross-ties and telegraph poles), but no data on individual exposures were available. The study population was restricted to men employed during the period 1950-1975, and their cancer morbidity was checked through the cancer registries. The total cancer incidence was somewhat lower than expected, 129 cases versus 137 expected [standardized incidence ratio (SIR) 0.94]. Increased risks in both countries combined were observed for lip cancer (SIR 2.50, 95% confidence interval (95% CI) 0.81-5.83), skin cancer (SIR 2.37, 95% CI 1.08-4.50), and malignant lymphoma (SIR 1.9, 95% CI 0.83-3.78). Exposure to sunlight may have contributed to the risk of lip and skin cancer. The small number of cancer cases does not permit valid conclusions. The findings indicate that impregnating wood with creosote in earlier decades increased the risk of skin cancer.

  5. Neurotoxicity of Acrylamide in Exposed Workers

    PubMed Central

    Pennisi, Manuela; Malaguarnera, Giulia; Puglisi, Valentina; Vinciguerra, Luisa; Vacante, Marco; Malaguarnera, Mariano

    2013-01-01

    Acrylamide (ACR) is a water-soluble chemical used in different industrial and laboratory processes. ACR monomer is neurotoxic in humans and laboratory animals. Subchronic exposure to this chemical causes neuropathies, hands and feet numbness, gait abnormalities, muscle weakness, ataxia, skin and in some cases, cerebellar alterations. ACR neurotoxicity involves mostly the peripheral but also the central nervous system, because of damage to the nerve terminal through membrane fusion mechanisms and tubulovescicular alterations. Nevertheless, the exact action mechanism is not completely elucidated. In this paper we have reviewed the current literature on its neurotoxicity connected to work-related ACR exposure. We have analyzed not only the different pathogenetic hypotheses focusing on possible neuropathological targets, but also the critical behavior of ACR poisoning. In addition we have evaluated the ACR-exposed workers case studies. Despite all the amount of work which have being carried out on this topic more studies are necessary to fully understand the pathogenetic mechanisms, in order to propose suitable therapies. PMID:23985770

  6. Thyroid hormones in chronic heat exposed men

    NASA Astrophysics Data System (ADS)

    Gertner, A.; Israeli, R.; Lev, A.; Cassuto, Y.

    1983-03-01

    Previous reports have indicated that thyroid gland activity, is depressed in the heat. Total thyroxine (T4) and triiodothyronine (T3) serum levels in 17 workers of the metal work shop at a plant near the Dead Sea and 8 workers in Beer Sheva, Israel were examined. The metal workshop of the plant near the Dead Sea is part of a large chemical plant. The one in Beer Sheva is part of a large construction company. Maintenance work, as well as metal work projects are performed in both workshops. During the work shifts, the workers of the Dead Sea plant were exposed to temperatures ranging from 30 36°C (May Oct.) and 14 21°C (Dec. Feb). In Beer Sheva the range was 25 32°C (June Sept.) and 10 17°C (Dec. Feb.). Total T4 was measured by competitive protein binding and total T3 by radioimmunoassay in blood drawn before work (0700) in July and January. In summer. T4 was higher and T3 was lower for both groups than in winter. The observed summer T3 decrease may result from depressed extrathyroidal conversion of T4 to T3. We conclude that the regulation of energy metabolism in hot climates may be related to extrathyroidal conversion of T4 to T3.

  7. Single authentication: exposing weighted splining artifacts

    NASA Astrophysics Data System (ADS)

    Ciptasari, Rimba W.

    2016-05-01

    A common form of manipulation is to combine parts of the image fragment into another different image either to remove or blend the objects. Inspired by this situation, we propose a single authentication technique for detecting traces of weighted average splining technique. In this paper, we assume that image composite could be created by joining two images so that the edge between them is imperceptible. The weighted average technique is constructed from overlapped images so that it is possible to compute the gray level value of points within a transition zone. This approach works on the assumption that although splining process leaves the transition zone smoothly. They may, nevertheless, alter the underlying statistics of an image. In other words, it introduces specific correlation into the image. The proposed idea dealing with identifying these correlations is to generate an original model of both weighting function, left and right functions, as references to their synthetic models. The overall process of the authentication is divided into two main stages, which are pixel predictive coding and weighting function estimation. In the former stage, the set of intensity pairs {Il,Ir} is computed by exploiting pixel extrapolation technique. The least-squares estimation method is then employed to yield the weighted coefficients. We show the efficacy of the proposed scheme on revealing the splining artifacts. We believe that this is the first work that exposes the image splining artifact as evidence of digital tampering.

  8. Risk and Protective Profiles Among Never Exposed, Single Form, and Multiple Form Violence Exposed Youth

    PubMed Central

    Nurius, Paula S.; Russell, Patricia L.; Herting, Jerald R.; Hooven, Carole; Thompson, Elaine A.

    2010-01-01

    This investigation integrated violence exposure with critical risk and protective factors linked to healthy adolescent adaptation and transition into early adulthood. A racially diverse sample of 848 adolescents identified as at-risk for school drop-out were assessed for no, single, or multiple forms of violence exposure. MANOVA tests revealed that youth with single form victimization fared more poorly than never-exposed youth, and that multiple-form victimization held the greatest jeopardy to development. Youth with multiple-form victimization reported significantly elevated risk factors (emotional distress, life stress, suicide risk, risky behaviors) and lower protective factors (social support, school engagement, family structure) than both single-form and never-exposed youth. Implications are discussed for preventive and early intervention programming and for examining the transition of at-risk youth into young adulthood. PMID:21494415

  9. A Successful Crayfish Invader Is Capable of Facultative Parthenogenesis: A Novel Reproductive Mode in Decapod Crustaceans

    PubMed Central

    Buřič, Miloš; Hulák, Martin; Kouba, Antonín

    2011-01-01

    Biological invasions are impacting biota worldwide, and explaining why some taxa tend to become invasive is of major scientific interest. North American crayfish species, particularly of the family Cambaridae, are prominent invaders in freshwaters, defying the “tens rule” which states that only a minority of species introduced to new regions become established, and only a minority of those become invasive and pests. So far, success of cambarid invaders has largely been attributed to rapid maturation, high reproductive output, aggressiveness, and tolerance to pollution. We provide experimental evidence that females of one cambarid species particularly widespread in Europe, the spiny-cheek crayfish Orconectes limosus, are capable of facultative parthenogenesis. Such reproductive mode has never before been recognized in decapods, the most diverse crustacean order. As shown by analysis of seven microsatellite loci, crayfish females kept physically separated from males produced genetically homogeneous offspring identical with maternal individuals; this suggests they reproduced by apomixis, unlike those females which mated with males and had a diverse offspring. Further research is needed to clarify what environmental conditions are necessary for a switch to parthenogenesis in O. limosus, and what role it plays in natural crayfish populations. However, if such reproductive plasticity is present in other cambarid crayfish species, it may contribute to the overwhelming invasive success of this group. PMID:21655282

  10. A successful crayfish invader is capable of facultative parthenogenesis: a novel reproductive mode in decapod crustaceans.

    PubMed

    Buřič, Miloš; Hulák, Martin; Kouba, Antonín; Petrusek, Adam; Kozák, Pavel

    2011-01-01

    Biological invasions are impacting biota worldwide, and explaining why some taxa tend to become invasive is of major scientific interest. North American crayfish species, particularly of the family Cambaridae, are prominent invaders in freshwaters, defying the "tens rule" which states that only a minority of species introduced to new regions become established, and only a minority of those become invasive and pests. So far, success of cambarid invaders has largely been attributed to rapid maturation, high reproductive output, aggressiveness, and tolerance to pollution. We provide experimental evidence that females of one cambarid species particularly widespread in Europe, the spiny-cheek crayfish Orconectes limosus, are capable of facultative parthenogenesis. Such reproductive mode has never before been recognized in decapods, the most diverse crustacean order. As shown by analysis of seven microsatellite loci, crayfish females kept physically separated from males produced genetically homogeneous offspring identical with maternal individuals; this suggests they reproduced by apomixis, unlike those females which mated with males and had a diverse offspring. Further research is needed to clarify what environmental conditions are necessary for a switch to parthenogenesis in O. limosus, and what role it plays in natural crayfish populations. However, if such reproductive plasticity is present in other cambarid crayfish species, it may contribute to the overwhelming invasive success of this group.

  11. The SPORES experiment of the EXPOSE-R mission: Bacillus subtilis spores in artificial meteorites

    NASA Astrophysics Data System (ADS)

    Panitz, Corinna; Horneck, Gerda; Rabbow, Elke; Rettberg, Petra; Moeller, Ralf; Cadet, Jean; Douki, Thierry

    2015-01-01

    The experiment SPORES `Spores in artificial meteorites' was part of European Space Agency's EXPOSE-R mission, which exposed chemical and biological samples for nearly 2 years (March 10, 2009 to February 21, 2011) to outer space, when attached to the outside of the Russian Zvezda module of the International Space Station. The overall objective of the SPORES experiment was to address the question whether the meteorite material offers enough protection against the harsh environment of space for spores to survive a long-term journey in space by experimentally mimicking the hypothetical scenario of Lithopanspermia, which assumes interplanetary transfer of life via impact-ejected rocks. For this purpose, spores of Bacillus subtilis 168 were exposed to selected parameters of outer space (solar ultraviolet (UV) radiation at λ>110 or >200 nm, space vacuum, galactic cosmic radiation and temperature fluctuations) either as a pure spore monolayer or mixed with different concentrations of artificial meteorite powder. Total fluence of solar UV radiation (100-400 nm) during the mission was 859 MJ m-2. After retrieval the viability of the samples was analysed. A Mission Ground Reference program was performed in parallel to the flight experiment. The results of SPORES demonstrate the high inactivating potential of extraterrestrial UV radiation as one of the most harmful factors of space, especially UV at λ>110 nm. The UV-induced inactivation is mainly caused by photodamaging of the DNA, as documented by the identification of the spore photoproduct 5,6-dihydro-5(α-thyminyl)thymine. The data disclose the limits of Lithopanspermia for spores located in the upper layers of impact-ejected rocks due to access of harmful extraterrestrial solar UV radiation.

  12. Comparative Toxicological Study between Exposed and Non-Exposed Farmers to Organophosphorus Pesticides

    PubMed Central

    Taghavian, Fariba; Vaezi, Gholamhassan; Abdollahi, Mohammad; Malekirad, Ali Akbar

    2016-01-01

    Objective The purpose of this work was to compare DNA damage, acetylcholinesterase (AChE) activity, inflammatory markers and clinical symptoms in farmers exposed to organophosphorus pesticides to individuals that had no pesticide exposure. Materials and Methods We conducted a cross-sectional survey with a total of 134 people. The subject group consisted of 67 farmers who were exposed to organophosphorus pesticides. The control group consisted of 67 people without any contact with pesticides matched with the subject group in terms of age, gender, and didactics. Oxidative DNA damage, the activities of AChE, interleukin-6 (IL6), IL10 and C-reactive protein (CRP) in serum were measured and clinical examinations conducted in order to register all clinical signs. Results Compared with the control group, substantial gains were observed in the farmers’ levels of oxidative DNA damage, IL10 and CRP. There was significantly less AChE activity in farmers exposed to organophosphorus pesticides. The levels of IL6 in both groups did not significantly differ. Conclusion The outcomes show that exposure to organophosphorus pesticides may cause DNA oxidative damage, inhibit AChE activity and increase the serum levels of inflammatory markers. Using biological materials instead of chemical pesticides and encouraging the use of safety equipment by farmers are some solutions to the adverse effects of exposure to organophosphorous pesticides. PMID:27054123

  13. Comparative genomic hybridization study of arsenic-exposed and non-arsenic-exposed urinary transitional cell carcinoma

    SciTech Connect

    Hsu, L.-I; Chiu, Allen W.; Pu, Y.-S.; Wang, Y.-H.; Huan, Steven K.; Hsiao, C.-H.; Hsieh, F.-I; Chen, C.-J.

    2008-03-01

    To compare the differences in DNA aberrations between arsenic-exposed and non-arsenic-exposed transitional cell carcinoma (TCC), we analyzed 19 arsenic-exposed and 29 non-arsenic-exposed urinary TCCs from Chi-Mei Hospital using comparative genomic hybridization. DNA aberrations were detected in 42 TCCs including 19 arsenic-exposed and 23 non-arsenic-exposed TCCs. Arsenic-exposed TCCs had more changes than unexposed TCCs (mean {+-} SD, 6.6 {+-} 2.9 vs. 2.9 {+-} 2.2). Arsenic exposure was significantly associated with the number of DNA aberrations after adjustment for tumor stage, tumor grade and cigarette smoking in multiple regression analysis. The most frequent DNA gains, which were strikingly different between arsenic-exposed and non-arsenic-exposed TCCs, included those at 1p, 4p, 4q and 8q. A much higher frequency of DNA losses in arsenic-exposed TCCs compared with non-arsenic-exposed TCCs was observed in 10q, 11p and 17p. Chromosomal loss in 17p13 was associated not only with arsenic exposure, but also with tumor stage and grade. The p53 immunohistochemistry staining showed that chromosome 17p13 loss was associated with either p53 no expression (25%) or p53 overexpression (75%). The findings suggest that long-term arsenic exposure may increase the chromosome abnormality in TCC, and 17p loss plays an important role in arsenic-induced urinary carcinogenesis.

  14. Degradation of HEPA filters exposed to DMSO

    SciTech Connect

    Bergman, W.; Wilson, K.; Larsen, G.

    1995-02-01

    Dimethyl sulfoxide (DMSO) sprays are being used to remove the high explosive (HE) from nuclear weapons in the process of their dismantlement. A boxed 50 cmf HEPA filter with an integral prefilter was exposed to DMSO vapor and aerosols that were generated by a spray nozzle to simulate conditions expected in the HE dissolution operation. After 198 hours of operation, the pressure drop of the filter had increased form 1.15 inches to 2,85 inches, and the efficiency for 0.3 {mu}m dioctyl sebacate (DOS) aerosols decreased form 99.992% to 98.6%. Most of the DMSO aerosols had collected as a liquid pool inside the boxed HEPA. The liquid was blown out of the filter exit with 100 cmf air flow at the end of the test. Since the filter still met the minimum allowed efficiency of 99.97% after 166 hours of exposure, we recommend replacing the filter every 160 hours of operation or sooner if the pressure drop increases by 50%. Examination of the filter showed that visible cracks appeared at the joints of the wooden frame and a portion of the sealant had pulled away from the frame. Since all of the DMSO will be trapped in the first HEPA filter, the second HEPA filter should not suffer from DMSO degradation. Thus the combined efficiency for the first filter (98.6%) and the second filter (99.97%) is 99.99996% for 0.3 {mu}m particles. If the first filter is replaced prior to its degradation, each of the filters will have 99.97% efficiency, and the combined efficiency will be 99.999991%. The collection efficiency for DMSO/HE aerosols will be much higher because the particle size is much greater.

  15. Assessing the photoaging process at sun exposed and non-exposed skin using fluorescence lifetime spectroscopy

    NASA Astrophysics Data System (ADS)

    Saito Nogueira, Marcelo; Kurachi, Cristina

    2016-03-01

    Photoaging is the skin premature aging due to exposure to ultraviolet light, which damage the collagen, elastin and can induce alterations on the skin cells DNA, and, then, it may evolve to precancerous lesions, which are widely investigated by fluorescence spectroscopy and lifetime. The fluorescence spectra and fluorescence lifetime analysis has been presented as a technique of great potential for biological tissue characterization at optical diagnostics. The main targeted fluorophores are NADH (nicotinamide adenine dinucleotide) and FAD (flavin adenine dinucleotide), which have free and bound states, each one with different average lifetimes. The average lifetimes for free and bound NADH and FAD change according to tissue metabolic alterations and may contribute to a non-invasive clinical investigation of injuries such as skin lesions. These lesions and the possible areas where they may develop can be interrogated using fluorescence lifetime spectroscopy taking into account the variability of skin phototypes and the changes related to melanin, collagen and elastin, endogenous fluorophores which have emissions that spectrally overlap to the NADH and FAD emission. The objective of this study is to assess the variation on fluorescence lifetimes of normal skin at sun exposed and non-exposed areas and associate this variation to the photoaging process.

  16. Ecophysiological tolerance of duckweeds exposed to copper.

    PubMed

    Kanoun-Boulé, Myriam; Vicente, Joaquim A F; Nabais, Cristina; Prasad, M N V; Freitas, Helena

    2009-01-18

    Although essential for plants, copper can be toxic when present in supra-optimal concentrations. Metal polluted sites, due to their extreme conditions, can harbour tolerant species and/or ecotypes. In this work we aimed to compare the physiological responses to copper exposure and the uptake capacities of two species of duckweed, Lemna minor (Lm(EC1)) and Spirodela polyrrhiza (SP), from an abandoned uranium mine with an ecotype of L. minor (Lm(EC2)) from a non-contaminated pond. From the lowest Cu concentration exposure (25microM) to the highest (100microM), Lm(EC2) accumulated higher amounts of copper than Lm(EC1) and SP. Dose-response curves showed that Cu content accumulated by Lm(EC2) increases linearly with Cu treatment concentrations (r(2)=0.998) whereas quadratic models were more suitable for Lm(EC1) and SP (r(2)=0.999 and r(2)=0.998 for Lm(EC1) and SP, respectively). A significant concentration-dependent decline of chlorophyll a (chl a) and carotenoid occurred as a consequence of Cu exposure. These declines were significant for Lm(EC2) exposed to the lowest Cu concentration (25microM) whereas for Lm(EC1) and SP a significant decrease in chl a and carotenoids was observed only at 50 and 100microM-Cu. Electric conductivity (EC) and malondialdehyde (MDA) content increased after Cu exposure, indicating oxidative stress. Significant increase of EC was observed in Lm(EC2) for all Cu concentrations whereas the increase for Lm(EC1) and SP became significant only after an exposure to 50microM-Cu. On the contrary, for Lm(EC1), SP, and Lm(EC2), MDA content significantly increased even at the lowest concentration. Protein content and catalase (CAT) activity showed a decrease with an increase in Cu concentration. For the species Lm(EC1) and SP, a significant effect of copper on CAT activity was observed only at the highest concentration (100microM-Cu) whereas, for Lm(EC2), this effect started to be significant after an exposure to 50microM-Cu. Superoxide dismutase (SOD

  17. Distribution and conservation standing of West Virginia crayfishes

    USGS Publications Warehouse

    Loughman, Zachary J.; Welsh, Stuart

    2010-01-01

    The diversity of crayfishes in West Virginia represents a transition between the species-rich southern Appalachian faunas and the depauperate crayfish diversity in the northeastern United States. Currently, 22 described species occur in the state, of which 6 are given S1 status, and 3 are introduced species. One species, Orconectes limosus (Spinycheek Crayfish) is considered extirpated within the past decade. Imperiled species include Cambarus veteranus (Big Sandy Crayfish),Cambarus elkensis (Elk River Crayfish), Cambarus longulus (Atlantic Slope Crayfish), andCambarus nerterius (Greenbrier Cave Crayfish). Three species—O. virilis (Virile Crayfish),Orconectes rusticus (Rusty Crayfish), and Procambarus zonangulus (Southern White River Crawfish)—have introduced populations within the state. Procambarus acutus (White River Crawfish) occurs in bottomland forest along the Ohio River floodplain, and is considered native. Several undescribed taxa have been identified and currently are being described. A statewide survey was initiated in 2007 to document the current distribution and conservation status of crayfishes in West Virginia.

  18. 9 CFR 78.32 - Brucellosis exposed swine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Brucellosis exposed swine. 78.32... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BRUCELLOSIS Restrictions on Interstate Movement of Swine Because of Brucellosis § 78.32 Brucellosis exposed swine....

  19. 9 CFR 78.23 - Brucellosis exposed bison.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Brucellosis exposed bison. 78.23... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BRUCELLOSIS Restrictions on Interstate Movement of Bison Because of Brucellosis § 78.23 Brucellosis exposed...

  20. 9 CFR 78.8 - Brucellosis exposed cattle.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Brucellosis exposed cattle. 78.8... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BRUCELLOSIS Restrictions on Interstate Movement of Cattle Because of Brucellosis § 78.8 Brucellosis exposed...

  1. 9 CFR 78.8 - Brucellosis exposed cattle.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... establishments. (1) Finished fed cattle from a quarantined feedlot may be moved interstate (i) Directly to a...) Movement to quarantined feedlots. Brucellosis exposed cattle for which no claim for indemnity is being made... brucellosis exposed cattle and then directly to a quarantined feedlot, or from a farm of origin directly to...

  2. 9 CFR 78.8 - Brucellosis exposed cattle.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... establishments. (1) Finished fed cattle from a quarantined feedlot may be moved interstate (i) Directly to a...) Movement to quarantined feedlots. Brucellosis exposed cattle for which no claim for indemnity is being made... brucellosis exposed cattle and then directly to a quarantined feedlot, or from a farm of origin directly to...

  3. 9 CFR 78.8 - Brucellosis exposed cattle.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... establishments. (1) Finished fed cattle from a quarantined feedlot may be moved interstate (i) Directly to a...) Movement to quarantined feedlots. Brucellosis exposed cattle for which no claim for indemnity is being made... brucellosis exposed cattle and then directly to a quarantined feedlot, or from a farm of origin directly to...

  4. Reactivity and Regulation in Children Prenatally Exposed to Cocaine

    ERIC Educational Resources Information Center

    Dennis, Tracy; Bendersky, Margaret; Ramsay, Douglas; Lewis, Michael

    2006-01-01

    Children prenatally exposed to cocaine may be at elevated risk for adjustment problems in early development because of greater reactivity and reduced regulation during challenging tasks. Few studies have examined whether cocaine-exposed children show such difficulties during the preschool years, a period marked by increased social and cognitive…

  5. The Psychobiology of Children Exposed to Marital Violence

    ERIC Educational Resources Information Center

    Saltzman, Kasey M.; Holden, George W.; Holahan, Charles J.

    2005-01-01

    We examined the psychological and physiological functioning of a community sample of children exposed to marital violence, comparing them to a clinical comparison group without marital violence exposure. Results replicated past findings of elevated levels of trauma symptomatology in this population. Further, children exposed to marital violence…

  6. Animal Cruelty by Children Exposed to Domestic Violence

    ERIC Educational Resources Information Center

    Currie, Cheryl L.

    2006-01-01

    Objective: The first objective of this study was to determine if children exposed to domestic violence were significantly more likely to be cruel to animals than children not exposed to violence. The second was to determine if there were significant age and gender differences between children who were and were not cruel to animals. Method: A…

  7. 31. VIEW OF ROOM 212 LOOKING NORTHWEST TOWARDS EXPOSED STUD ...

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

    31. VIEW OF ROOM 212 LOOKING NORTHWEST TOWARDS EXPOSED STUD WALL THAT SERVES AS DIVIDER TO ROOM 211. EXPOSED TRUSSWORK VISIBLE THROUGH TO NEXT ROOM. WOOD PANELED WALLS ARE PAINTED; FLOORS ARE WOOD. - Presidio of San Francisco, Cavalry Stables, Cowles Street, between Lincoln Boulevard & McDowell Street, San Francisco, San Francisco County, CA

  8. 46 CFR 108.223 - Guards on exposed equipment.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Guards on exposed equipment. 108.223 Section 108.223 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Construction and Arrangement Rails § 108.223 Guards on exposed equipment. Each unit...

  9. 46 CFR 108.223 - Guards on exposed equipment.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Guards on exposed equipment. 108.223 Section 108.223 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Construction and Arrangement Rails § 108.223 Guards on exposed equipment. Each unit...

  10. Evaluation performance of digital integrated circuits while exposed to radiation

    NASA Astrophysics Data System (ADS)

    Barbashov, V. M.; Trushkin, N. S.

    2016-10-01

    The methods of functional-logical simulation of digital integrated circuits (ICs) exposed to radiation are observed. It is shown that in a number of cases functional and electrical deterioration of ICs performances have both deterministic and non-deterministic nature. Methods for simulating IC failure exposed to radiation based on the model of fuzzy digital machine and Brauer probabilistic reliability machine are proposed.

  11. Outdoor polymeric insulators long-term exposed to HVDC

    SciTech Connect

    Soerqvist, T.; Vlastos, A.E.

    1997-04-01

    Field experience from outdoor polymeric insulators exposed to HVDC under natural contamination conditions is presented. This paper summarizes the peak leakage current statistics, the hydrophobicity and the surface material conditions studied by electron spectroscopy for chemical analysis (ESCA) and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. The results show a strong interrelation between the surface conditions and the performance with respect to leakage currents. Moreover, the results show that the surface conditions and the performance of the insulators exposed to HVDC are rather similar to those of the insulators exposed to HVAC.

  12. Hepatic function in workers occupationally exposed to carbon tetrachloride.

    PubMed Central

    Tomenson, J A; Baron, C E; O'Sullivan, J J; Edwards, J C; Stonard, M D; Walker, R J; Fearnley, D M

    1995-01-01

    OBJECTIVES--To identify any differences in hepatic function between workers exposed to carbon tetrachloride and controls, and to identify the best variable with which to examine any effects. METHODS--In a cross sectional study of hepatic function in workers occupationally exposed to carbon tetrachloride, 135 exposed employees were compared with 276 non-exposed controls. The exposed group was taken from three sites in the north west of England and the control group included non-exposed workers from one of these sites and another site located nearby. Demographic and alcohol consumption data were collected from both groups by questionnaire. Each member of the study group was allotted a notional estimated exposure to carbon tetrachloride, calculated from historic personal monitoring data and job category. A fasting sample of blood was taken from all participants and analysed for a variety of biochemical and haematological variables. The techniques of univariate and multivariate analysis of variance were used to investigate the effect on biochemical and haematological indices of a range of factors. RESULTS--Multivariate analysis of variance of four core liver function variables, alanine transaminase, aspartate transaminase, alkaline phosphatase, and gamma-glutamyl transferase, showed a significant difference between exposed and non-exposed workers. The univariate analyses identified increases in only alkaline phosphatase and gamma-glutamyl transferase within the exposed group and these did not show a significant dose-response relation. Univariate analysis of variance did show effects of alcohol and age on several variables. Significant differences between exposed and control groups for three haematological variables, haemoglobin, packed cell volume, and red blood count, were thought not to be due to the effects of exposure. Clinical review of exposed subjects with abnormal results did not show clinically evident disease that could have been associated with exposure to

  13. Non-disjunction mutations in Drosophila exposed to magnetic fields

    NASA Astrophysics Data System (ADS)

    Levengood, W. C.

    1987-09-01

    The frequency of XO mutations in Drosophila melanogaster was significantly higher than normal in magnetic field exposed, immature males, than in exposed, mature males. Mutation levels increased with magnetic field strength. Intercellular rings of black magnetic particles were formed in the high magnetic flux region of dorsally exposed, early stage pupae and to a lesser degree in the abdomen of young adult females. Orientation of minute, chromosome associated, magnetic domains within the microenvironment of the developing organism was believed to alter oxidative processes within maturing X+ sperm which during fertilization were incompatible with and destructive to an Xw chromosome in the zygote.

  14. Ventilatory function in workers exposed to tea and wood dust.

    PubMed

    Al Zuhair, Y S; Whitaker, C J; Cinkotai, F F

    1981-11-01

    Changes in ventilatory capacity during the work shift were studied in workers exposed to tea dust in tea-packing plants, wood dust in two furniture factories, and virtually no dust in an inoperational power station. The FEV1 and FVC in workers exposed to dust were found to decline during the work shift by a small but significant volume. The MMFR, Vmax 50% and Vmax 75% were to variable to display any trend. No dose-response relationship could be discerned between the fall in workers' ventilatory capacity and the concentrations of airborne dust or microbes to which they were exposed. Bronchodilators could reverse the fall in FEV1.

  15. Interior view of groundfloor porch showing exposed concrete floor slab ...

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

    Interior view of ground-floor porch showing exposed concrete floor slab system, facing west. - Albrook Air Force Station, Field Officer's Quarters, West side of Dargue Avenue Circle, Balboa, Former Panama Canal Zone, CZ

  16. Detail view of the exposed polychromatic aggregate ceiling designed and ...

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

    Detail view of the exposed polychromatic aggregate ceiling designed and cast by John Joseph Earley for the vehicular entrance portals to the courtyard - United States Department of Justice, Constitution Avenue between Ninth & Tenth Streets, Northwest, Washington, District of Columbia, DC

  17. 6. Interior view of unoccupied space looking up at exposed ...

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

    6. Interior view of unoccupied space looking up at exposed roof structure; showing HVAC duct work and wood structure; near center of building; view to northeast. - Ellsworth Air Force Base, Warehouse, 789 Twining Street, Blackhawk, Meade County, SD

  18. Detail of upper portion of southeast corner showing exposed rafters ...

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

    Detail of upper portion of southeast corner showing exposed rafters at eaves; camera facing northwest. - Mare Island Naval Shipyard, Supply Building, Walnut Avenue, southeast corner of Walnut Avenue & Fifth Street, Vallejo, Solano County, CA

  19. 98. DETAIL VIEW OF STORM DAMAGE AND EXPOSED SUBSTRUCTURE, NORTHWEST ...

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

    98. DETAIL VIEW OF STORM DAMAGE AND EXPOSED SUBSTRUCTURE, NORTHWEST SIDE OF 4TH TEE, LOOKING WEST - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  20. DARKDROID: Exposing the Dark Side of Android Marketplaces

    DTIC Science & Technology

    2016-06-01

    DARKDROID: EXPOSING THE DARK SIDE OF ANDROID MARKETPLACES UNIVERSITY OF CALIFORNIA JUNE 2016 FINAL TECHNICAL REPORT APPROVED FOR PUBLIC RELEASE...DATES COVERED (From - To) JUNE 2012 – DEC 2015 4. TITLE AND SUBTITLE DARKDROID: EXPOSING THE DARK SIDE OF ANDROID MARKETPLACES 5a. CONTRACT NUMBER N...and can be reverted to a known, clean state in a matter of seconds. Emulators, however, are fundamentally different from real devices, and previous

  1. Partially exposed polymer dispersed liquid crystals for boundary layer investigations

    NASA Technical Reports Server (NTRS)

    Parmar, Devendra S.; Singh, Jag J.

    1992-01-01

    A new configuration termed partially exposed polymer dispersed liquid crystal in which the liquid crystal microdroplets dispersed in a rigid polymer matrix are partially entrapped on the free surface of the thin film deposited on a glass substrate is reported. Optical transmission characteristics of the partially exposed polymer dispersed liquid crystal thin film in response to an air flow induced shear stress field reveal its potential as a sensor for gas flow and boundary layer investigations.

  2. Ozone exposed epithelial cells modify cocultured natural killer cells

    PubMed Central

    Müller, Loretta; Brighton, Luisa E.

    2013-01-01

    Ozone (O3) causes significant adverse health effects worldwide. Nasal epithelial cells (NECs) are among the first sites within the respiratory system to be exposed to inhaled air pollutants. They recruit, activate, and interact with immune cells via soluble mediators and direct cell-cell contacts. Based on our recent observation demonstrating the presence of natural killer (NK) cells in nasal lavages, the goal of this study was to establish a coculture model of NECs and NK cells and examine how exposure to O3 modifies this interaction. Flow cytometry analysis was used to assess immunophenotypes of NK cells cocultured with either air- or O3-exposed NECs. Our data show that coculturing NK cells with O3-exposed NECs decreased intracellular interferon-γ (IFN-γ), enhanced, albeit not statistically significant, IL-4, and increased CD16 expression on NK cells compared with air controls. Additionally, the cytotoxicity potential of NK cells was reduced after coculturing with O3-exposed NECs. To determine whether soluble mediators released by O3-exposed NECs caused this shift, apical and basolateral supernatants of air- and O3-exposed NECs were used to stimulate NK cells. While the conditioned media of O3-exposed NECs alone did not reduce intracellular IFN-γ, O3 enhanced the expression of NK cell ligands ULBP3 and MICA/B on NECs. Blocking ULBP3 and MICA/B reversed the effects of O3-exposed NECs on IFN-γ production in NK cells. Taken together, these data showed that interactions between NECs and NK cells in the context of O3 exposure changes NK cell activity via direct cell-cell interactions and is dependent on ULBP3/MICA/B expressed on NECs. PMID:23241529

  3. Risk and resilience factors of persons exposed to accidents

    PubMed Central

    HERTA, DANA – CRISTINA; BRÎNDAS, PAULA; TRIFU, RALUCA; COZMAN, DOINA

    2016-01-01

    Background and aims Resilience encompasses factors promoting effective functioning in the context of adversity. Data regarding resilience in the wake of accidental trauma is still scarce. The aim of the current study is to comparatively assess adaptive, life – promoting factors in persons exposed to motor vehicle accidents (MVA) vs. persons exposed to other types of accidents, and to identify psychological factors of resilience and vulnerability in this context of trauma exposure. Methods We assessed 93 participants exposed to accidents out of 305 eligible patients from the Clinical Rehabilitation Hospital and Cluj County Emergency Hospital. The study used Reasons for Living Inventory (RFL) and Life Events Checklist. Scores were comparatively assessed for RFL items, RFL scale and subscales in participants exposed to motor vehicle accidents (MVA) vs. participants exposed to other life – threatening accidents. Results Participants exposed to MVA and those exposed to other accidents had significantly different scores in 7 RFL items. Scores were high in 4 out of 6 RFL subscales for both samples and in most items comprising these subscales, while in the other 2 subscales and in some items comprising them scores were low. Conclusions Low fear of death, physical suffering and social disapproval emerge as risk factors in persons exposed to life – threatening accidents. Love of life, courage in life and hope for the future are important resilience factors after exposure to various types of life – threatening accidents. Survival and active coping beliefs promote resilience especially after motor vehicle accidents. Coping with uncertainty are more likely to foster resilience after other types of life – threatening accidents. Attachment of the accident victim to family promotes resilience mostly after MVA, while perceived attachment of family members to the victim promotes resilience after other types of accidents. PMID:27152078

  4. [Anemia in workers exposed to lead: update on differential diagnosis].

    PubMed

    Di Lorenzo, L; Soleo, L; Cassano, F; Elia, G; Schiavulli, N; Martino, M G; Corfiati, M; Bulfaro, D; Apostoli, P

    2005-01-01

    Occupational lead exposure can cause anemia at blood lead levels >50 microg/dl, as high as rarely occurs in industrialized countries nowadays. Whereas other forms of anemia are fairly probable to be found in lead exposed workers, especially in areas highly endemicfor extraoccupational anemias, such as beta thalassemia and iron deficiency anemia. The etiology of anemias has to be correctly defined in order to assess suitable therapeutical approaches and medicolegal consequences. The objective of this study is to verify in male lead exposed workers whether an accurate evaluation of hemocromocytometric parameters and of usual biological indices of lead exposure and effect on heme can differentiate the most common forms of anemia in Southern Italy. 68 workers occupationally exposed to low to moderate lead doses were studied and 59 workers of an alimentary plant have been taken as control group. On venous blood samples collected from these workers a complete hemocromocytometric test was performed and blood lead and erythrocytic zincoprotoporphyrin were determined. Anemia (Hb exposed workers and in a nonexposed worker. The reasoned evaluation of laboratory parameters led to identify among lead exposed workers four subjects with high probability of beta-thalassemic trait and two with lead poisoning anemia. Moreover a diagnostic algorithm was developed based on literature that seems to be able to discriminate lead poisoning from other causes of anemia in lead exposed workers in this study.

  5. The AMINO experiment: methane photolysis under Solar VUV irradiation on the EXPOSE-R facility of the International Space Station

    NASA Astrophysics Data System (ADS)

    Carrasco, Nathalie; Cottin, Hervé; Cloix, Mégane; Jérome, Murielle; Bénilan, Yves; Coll, Patrice; Gazeau, Marie-Claire; Raulin, François; Saiagh, Kafila; Chaput, Didier

    2015-01-01

    The scientific aim of the present campaign is to study the whole chain of methane photo-degradation, as initiated by Solar vacuum-ultraviolet irradiation in Titan's atmosphere. For this purpose, the AMINO experiment on the EXPOSE-R mission has loaded closed cells for gas-phase photochemistry in space conditions. Two different gas mixtures have been exposed, named Titan 1 and Titan 2, involving both N2-CH4 gas mixtures, without and with CO2, respectively. CO2 is added as a source of reactive oxygen in the cells. The cell contents were analysed thanks to infrared absorption spectroscopy, gas chromatography and mass spectrometry. Methane consumption leads to the formation of saturated hydrocarbons, with no detectable influence of CO2. This successful campaign provides a first benchmark for characterizing the whole methane photochemical system in space conditions. A thin film of tholin-like compounds appears to form on the cell walls of the exposed cells.

  6. Ion bombardment of cometary ices analogues: production of organic samples for the EXPOSE-R2 mission on the International Space Station

    NASA Astrophysics Data System (ADS)

    Baratta, G. A.; Chaput, D.; Cottin, H.; Fernandez Cascales, L.; Palumbo, M. E.; Strazzulla, G.

    2014-04-01

    We describe the preparation and characterization (by UV-Vis-IR spectroscopy) of a set of organic samples, stable at room temperature and above, that are part of the experiment "Photochemistry on the Space Station (PSS)" planned to be enclosed in the EXPOSE-R2 mission, which will be conducted on the EXPOSE-R facility, outside the International Space Station (ISS).

  7. Effects on LDEF exposed copper film and bulk

    NASA Technical Reports Server (NTRS)

    Peters, Palmer N.; Gregory, John C.; Christl, Ligia C.; Raikar, Ganesh N.

    1991-01-01

    Two forms of copper were exposed to the Long Duration Exposure Facility (LDEF) Mission 1 environment: a copper film, initially 74.2 plus or minus 1.1 nm thick sputter coated on a fused silica flat and a bulk piece of oxygen-free, high conductivity (OFHC) copper. The optical density of the copper film changed from 1.33 to 0.70 where exposed, and the film thickness increased to 106.7 plus or minus 0.5 nm where exposed. The exposed area appears purple by reflection and green by transmission for the thin film and maroon color for the bulk copper piece. The exposed areas increased in thickness, but only increase in the thickness of the thin film sample could be readily measured. The increase in film thickness is consistent with the density changes occurring during conversion of copper to an oxide. However, we have not been able to confirm appreciable conversion to an oxide by x-ray diffraction studies. We have not yet subjected the sample to e-beams or more abusive investigations out of concern that the film might be modified.

  8. Cardiovascular effects in viscose rayon workers exposed to carbon disulfide.

    PubMed

    Kotseva, K; Braeckman, L; De Bacquer, D; Bulat, P; Vanhoorne, M

    2001-01-01

    The objectives of this study were to investigate the cardiovascular effects in workers currently exposed to carbon disulfide (CS2) below the threshold limit value (TLV) of 31 mg/m3 and to determine the prevalence of coronary heart disease (CHD) after long-term exposure. 172 men (91 workers exposed to CS2 in a viscose rayon factory and 81 referent workers) were examined using a medical and job history questionnaire, Rose's questionnaire, and electrocardiography at rest, and by measuring blood pressure and serum lipids and lipoproteins. Personal exposures were monitored simultaneously with active sampling and findings were analyzed according to the NIOSH 1600 method. As a result of technical and organizational improvements, personal CS2 exposures were well below the TLV (5.4-13.02 mg/m3). No significant effect of CS2 on blood pressure or lipids (total cholesterol, HDL and LDL cholesterol, triglycerides, and apolipoproteins AI and B) was found, even after allowance for confounding factors. The prevalence of CHD (ECG abnormalities and chest pain) was higher in the viscose rayon workers than in the workers with no exposure but reached statistical significance for men with exposure histories often years and more only (cumulative CS9 index > or = 150 mg/m3, the most highly exposed group). The findings suggest that the coronary risk is increased in workers previously exposed to high CS2 concentrations but not in those exposed to CS2 levels below the current TLV.

  9. Effects on LDEF exposed copper film and bulk

    NASA Technical Reports Server (NTRS)

    Peters, Palmer N.; Gregory, John C.; Christl, Ligia C.; Raikar, Ganesh N.

    1992-01-01

    Two forms of copper were exposed to the Long Duration Exposure Facility (LDEF) Mission 1 environment: a copper film initially 74.2 plus or minus 1.1 nm thick sputter coated on a fused silical flat and a bulk piece of oxygen free, high conductivity (OFHC) copper. The optical density of the copper film changed from 1.33 to 0.70 where exposed and the film thickness increased to 106.7 plus or minus 0.5 nm where exposed. The exposed area appears purple by reflection and green by transmission for the thin film and maroon color for the bulk copper piece. The exposed areas increased in thickness, but only increase in the thickness of thin film samples could be readily measured. The increase in film thickness is consistent with the density changes occurring during conversion of copper to an oxide. However, we have not been able to confirm appreciable conversion to an oxide by x ray diffraction studies. We have not yet subjected the sample to e-beams or more abusive conditions out of concern that the film might be modified.

  10. Cytogenetic investigation of subjects professionally exposed to radiofrequency radiation.

    PubMed

    Maes, Annemarie; Van Gorp, Urbain; Verschaeve, Luc

    2006-03-01

    Nowadays, virtually everybody is exposed to radiofrequency radiation (RFR) from mobile phone base station antennas or other sources. At least according to some scientists, this exposure can have detrimental health effects. We investigated cytogenetic effects in peripheral blood lymphocytes from subjects who were professionally exposed to mobile phone electromagnetic fields in an attempt to demonstrate possible RFR-induced genetic effects. These subjects can be considered well suited for this purpose as their RFR exposure is 'normal' though rather high, and definitely higher than that of the 'general population'. The alkaline comet assay, sister chromatid exchange (SCE) and chromosome aberration tests revealed no evidence of RFR-induced genetic effects. Blood cells were also exposed to the well known chemical mutagen mitomycin C in order to investigate possible combined effects of RFR and the chemical. No cooperative action was found between the electromagnetic field exposure and the mutagen using either the comet assay or SCE test.

  11. Asbestos content in lungs of occupationally and nonoccupationally exposed individuals

    SciTech Connect

    Dodson, R.F.; Greenberg, S.D.; Williams, M.G. Jr.; Corn, C.J.; O'Sullivan, M.F.; Hurst, G.A.

    1984-07-06

    Previous reports have indicated that a majority of the population has asbestos bodies within their lungs. These studies generally have been carried out using cohorts from urban environments. The present study compares the asbestos body levels from three unique cohorts: (1) a nonoccupationally exposed group from a large urban environment having a relatively low asbestos content, (2) patients with lung cancer from a nonurban setting, and (3) amosite asbestos workers, who worked and lived in a rural setting. The number of asbestos bodies in both the urban nonoccupationally exposed group and the patients with lung cancer was generally found to be low or below limits of detectability, with the exceptions being those persons in whom an occupational exposure was eventually found. The ferruginous body content of the occupationally exposed group varied considerably between individuals as well as between sites within the same individual.

  12. Serum beta2-microglobulin in cadmium exposed workers.

    PubMed

    Piscator, M

    1978-09-01

    In cadmium exposed workers with renal tubular dysfunction the determination of beta2m in urine is an important diagnostic test. Cadmium exposure's influence on serum beta2m levels and its relationship to urinary excretion of beta2m were studied in 24 cadmium exposed workers with normal serum creatinine levels (less than 10 mg/l)) and no obvious tubular dysfunction. With increasing blood levels of cadmium beta2m was found to increase in serum. There was no concomitant increase in the urinary excretion of beta2m. Serum beta2m was not dependent on serum creatinine within the range studied. The results suggest that for evaluating renal glomerular function in cadmium exposed workers, it might be better to use the serum creatinine level, creatinine clearance or inulin clearance since beta2m might give some false positive results.

  13. Temporary impairment of reproduction in freshwater teleost exposed to nonylphenol.

    PubMed

    Cardinali, Marco; Maradonna, Francesca; Olivotto, Ike; Bortoluzzi, Guido; Mosconi, Gilberto; Polzonetti-Magni, Alberta M; Carnevali, Oliana

    2004-06-01

    New born guppies, Poecilia reticulata, were exposed to a sublethal concentration of nonylphenol (NP) for 90 days, with the aim of evaluating the influence that this pollutant has on reproductive functions. At the end of treatment, the gender balance was significantly biased towards females (sex ratio = 0.3 males per female). Treated males displayed anomalous transcription of vitellogenin in correlation with a significant reduction of the gonadosomatic index (GSI); however, an increase of vitellogenin gene transcription, correlating directly with an increase in GSI, was observed in NP treated females. The hepatosomatic index (HSI) was significantly increased in exposed males and females. Females exposed to NP showed no alteration of sexual behavior or reproduction. These findings in guppies suggest that NP has estrogenic potency sufficient to disturb reproduction. Effects were transitory in nature because three months in uncontaminated water allowed males to recover normal sexual efficiency.

  14. Urinary kallikrein activity of workers exposed to lead.

    PubMed Central

    Boscolo, P; Porcelli, G; Cecchetti, G; Salimei, E; Iannaccone, A

    1978-01-01

    Two groups of men of different age ranges and with the same period of lead exposure were selected for study in a recently opened car-battery factory. Two other groups of age-matched men, not exposed to heavy metals in their work, were used as controls. Morning urines were collected from control and exposed groups for determination of urinary kallikrein activity, urinary delta-amino-levulinic acid (ALA) and lead levels. The environmental lead levels and the urinary ALA and lead values indicated that exposure in the factory was not heavy. The older group of lead-exposed workers showed greatly reduced urinary kallikrein activity compared with that of the age-matched controls. In contrast, the younger group did not show any significant alteration in urinary kallikrein excretion. PMID:698136

  15. Neurodevelopment of adopted children exposed in utero to cocaine.

    PubMed Central

    Nulman, I; Rovet, J; Altmann, D; Bradley, C; Einarson, T; Koren, G

    1994-01-01

    OBJECTIVE: To assess the neurodevelopment of adopted children who had been exposed in utero to cocaine. DESIGN: A case-control observational study. PARTICIPANTS: Twenty-three children aged 14 months to 6.5 years exposed in utero to cocaine and their adoptive mothers, and 23 age-matched control children not exposed to cocaine and their mothers, matched with the adoptive mothers for IQ and socioeconomic status. SETTING: The Motherisk Programme at The Hospital for Sick Children, Toronto, a consultation service for chemical exposure during pregnancy. MAIN OUTCOME MEASURES: Height, weight and head circumference at birth and at follow-up, and achievement on standard tests of cognitive and language development. RESULTS: Compared with the control group, children exposed in utero to cocaine had an 8-fold increased risk for microcephaly (95% confidence interval 1.5 to 42.3); they also had a lower mean birth weight (p = 0.005) and a lower gestational age (p = 0.002). In follow-up the cocaine-exposed children caught up with the control subjects in weight and stature but not in head circumference (mean 31st percentile v. 63rd percentile) (p = 0.001). Although there were no significant differences between the two groups in global IQ, the cocaine-exposed children had significantly lower scores than the control subjects on the Reynell language test for both verbal comprehension (p = 0.003) and expressive language (p = 0.001). CONCLUSIONS: This is the first study to document that intrauterine exposure to cocaine is associated with measurable and clinically significant toxic neurologic effects, independent of postnatal home and environmental confounders. Because women who use cocaine during pregnancy almost invariably smoke cigarettes and often use alcohol, it is impossible to attribute the measured toxic effects to cocaine alone. PMID:7954158

  16. Quantifying bank retreat rates with exposed tree roots

    NASA Astrophysics Data System (ADS)

    Stotts, S. N.; O'Neal, M. A.; Pizzuto, J. E.

    2013-12-01

    In this study we use a biometric approach based on anatomical changes in the wood of exposed tree roots to quantify riverbank erosion along South River, Va, a site where commonly applied techniques for determining bank erosion rates are either not appropriate due to the required spatial scale of analysis (i.e., erosion pins, traditional surveys, LiDAR analysis) or have failed to detect obvious erosion (i.e. photogrammetric techniques). We sampled 78 exposed roots from 24 study reaches and processed them both macroscopically (2 to 20 times magnification) and microscopically (20 to 100 times magnification), comparing the estimated erosion rates between levels of magnification and to those obtained with photogrammetric techniques. We found no statistical differences between the output of macroscopic and microscopic analyses (t-test, alpha =0.01) but encountered difficulty in identifying the year of root exhumation in some samples. Therefore, we suggest analyzing roots at both levels of magnification to increase confidence and obtain erosion rate estimates from every sample. When comparing exposed root analysis to photogrammetric techniques, the results indicate that the exposed root approach is a feasible and effective method for estimating decadal to centennial scale bank erosion. In addition to producing erosion rates statistically indistinguishable from photogrammetric techniques (t-test, alpha = 0.01), exposed root analysis demonstrated more consistent detection of erosion. The results of this study indicate that exposed tree root analysis is a robust tool that provides insights into decadal scale erosion where other commonly applied techniques may not be appropriate or easily applied.

  17. Improvement of contact resistances on plasma-exposed silicon carbide

    NASA Astrophysics Data System (ADS)

    Cheung, R.; Hay, J.; van der Drift, E.; Gao, W.

    2000-11-01

    We demonstrate improvements in the specific contact resistance of unannealed ohmic contacts by at least one order of magnitude on undoped 6H-SiC (silicon carbide, SiC). The improved contacts with a specific resistance of 0.3 Ω cm 2 have been fabricated on SiC surfaces exposed to an argon plasma at -80 V for 2.5 min. Under these plasma conditions, the top monolayers of the plasma-exposed SiC surface is silicon rich as revealed by X-ray photoelectron spectroscopy, and the surface roughness is decreased by a factor of 2 from atomic force microscopy analysis.

  18. Study of indium tin oxide films exposed to atomic axygen

    NASA Technical Reports Server (NTRS)

    Snyder, Paul G.; De, Bhola N.; Woollam, John A.; Coutts, T. J.; Li, X.

    1989-01-01

    A qualitative simulation of the effects of atomic oxygen has been conducted on indium tin oxide (ITO) films prepared by dc sputtering onto room-temperature substrates, by exposing them to an RF-excited oxygen plasma and characterizing the resulting changes in optical, electrical, and structural properties as functions of exposure time with ellipsometry, spectrophotometry, resistivity, and X-ray measurements. While the films thus exposed exhibit reduced resistivity and optical transmission; both of these effects, as well as partial crystallization of the films, may be due to sample heating by the plasma. Film resistivity is found to stabilize after a period of exposure.

  19. Development of orbital experimental equipment for JEM exposed facility

    NASA Astrophysics Data System (ADS)

    Satoh, Masakazu; Morioka, Mikio; Katoh, Toshio; Fusegi, Katsumi; Nakao, Keizou; Ban, Hiroyuki; Ohashi, Tomoaki; Amagata, Raita; Arafune, Kuniyuki

    1993-05-01

    The Exposed Facility Flyer Unit (EFFU) is an orbital experimental facility to be mounted on the free flyer Space Flyer Unit (SFU). The SFU is scheduled to be launched by an H-11 launch vehicle in early 1995. After several months in orbit, the SFU will be retrieved by the Space Shuttle. The EFFU will provide experience in developing the key technology of the Exposed Facility of Japanese Experiment Module (JEM), which will be attached to the Space Station Freedom in the late 1990's. The EFFU proto-flight model test was concluded. This paper describes the development of the EFFU.

  20. Lung cancer in rats exposed to fibrogenic dusts

    SciTech Connect

    Holland, L.M.; Wilson, J.S.; Tillery, M.I.; Smith, D.M.

    1984-01-01

    Fischer-344 rats were exposed to quartz dusts and to quartz-bearing oil shale dusts in long-term inhalation studies. Aerosol concentrations of 12 mg/m/sup 3/ and 152-176 mg/m/sup 3/ for quartz and shale dusts, respectively, were used in exposure regimens lasting up to two years. Pulmonary fibrosis was observed in most animals surviving beyond 400 days. Adenocarcinomas and epidermoid carcinomas of the lung were observed in animals from all exposure groups, including those exposed to quartz alone. The pulmonary tumors were a late effect, with the earliest lung tumor being observed after 651 days. 13 references, 10 figures, 4 tables.

  1. Organic samples produced by ion bombardment of ices for the EXPOSE-R2 mission on the International Space Station

    NASA Astrophysics Data System (ADS)

    Baratta, G. A.; Chaput, D.; Cottin, H.; Fernandez Cascales, L.; Palumbo, M. E.; Strazzulla, G.

    2015-12-01

    We describe the preparation and characterization (by UV-vis-IR spectroscopy) of a set of organic samples, stable at room temperature and above, that are part of the experiment "Photochemistry on the Space Station (PSS)" planned to be enclosed in the EXPOSE-R2 mission, which will be conducted on the EXPOSE-R facility. The core facility is placed outside the International Space Station (ISS) on the Universal Platform D (URM-D platform) of the Russian module Zvezda. The organic materials are prepared in the Catania laboratory after 200 keV He+ irradiation of icy mixtures, namely N2:CH4:CO deposited at 16 K on MgF2 windows furnished by the European Space Agency. It is widely accepted that such a kind of materials produced by energetic processing are representative of organic material in some astrophysical environments as comets. Once expelled from comets these materials are exposed to solar radiation during their interplanetary journey before they eventually land on Earth and other planetary objects where they might give a contribution to the chemical and pre-biotical evolution. In particular our residues contain different chemical groups, including triple CN bonds that are considered relevant to pre-biotic chemistry. Therefore the samples will be exposed, for several months, to the solar ultraviolet photons that are a major source of energy to initiate chemical evolution in the solar system. This will allow analysis of their destruction or modification and evaluation of their lifetime in the interplanetary medium. The samples have three different thicknesses that will allow estimation of the depth profile of destruction. This experiment overcomes the limits of ground tests which do not reproduce exactly the space parameters.

  2. Organic samples produced by ion bombardment of ices for the EXPOSE-R2 mission on the International Space Station

    NASA Astrophysics Data System (ADS)

    Baratta, G.; Chaput, D.; Cottin, H.; Fernandez Cascales, L.; Palumbo, M.; Strazzulla, G.

    2014-07-01

    We describe the preparation and characterization (by UV-Vis-IR spectroscopy) of a set of organic samples, stable at room temperature and above, that are part of the experiment "Photochemistry on the Space Station (PSS)" planned to be enclosed in the EXPOSE-R2 mission, which will be conducted on the EXPOSE-R facility, outside the International Space Station (ISS). The organic materials are prepared in the Catania laboratory after 200 keV He+ irradiation of icy mixtures, namely N_2:CH_4:CO deposited at 16 K on MgF_2 windows furnished by European Space Agency. It is widely accepted that such kind of materials produced by energetic processing are representative of organic material in astrophysical environments such as, e.g., comets. Once expelled from comets these materials are exposed to solar radiation during their interplanetary journey before they eventually land on the Earth and other planetary objects where they might give a contribution to the chemical and pre-biotical evolution. In particular our residues contain different chemical groups, including triple CN bonds that are considered relevant to pre-biotic chemistry (e.g. Palumbo et al., 2000). Therefore the samples will be exposed, for several months, to the solar ultraviolet photons that are a major source of energy to initiate chemical evolution in the Solar System. This will allow analysis of their destruction and evaluation of their lifetime in the interplanetary medium. The samples have three different thicknesses (about 200, 130, 65 nm) that will allow the estimation of the depth profile of destruction (e.g., Baratta et al., 2002). This experiment overcomes the limits of ground tests which do not reproduce exactly the space parameters.

  3. 7 CFR 28.37 - Exposing of samples for classification.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... CONTAINER REGULATIONS COTTON CLASSING, TESTING, AND STANDARDS Regulations Under the United States Cotton... 7 Agriculture 2 2010-01-01 2010-01-01 false Exposing of samples for classification. 28.37 Section 28.37 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING...

  4. 12. A LONG RUN OF EXPOSED TOP SURFACE, NORTH TRAINING ...

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

    12. A LONG RUN OF EXPOSED TOP SURFACE, NORTH TRAINING WALL, ABOUT 1,500 FEET EAST OF THE FEDERAL CHANNEL MOUTH. VIEW TO WEST, TOWARD SAN FRANCISCO. - Oakland Harbor Training Walls, Mouth of Federal Channel to Inner Harbor, Oakland, Alameda County, CA

  5. A pill to treat people exposed to radioactive materials

    SciTech Connect

    Abergel, Rebecca

    2013-10-31

    Berkeley Lab's Rebecca Abergel discusses "A pill to treat people exposed to radioactive materials" in this Oct. 28, 2013 talk, which is part of a Science at the Theater event entitled Eight Big Ideas. Go here to watch the entire event with all 8 speakers:

  6. The PrimeTime Expose: Reactions and Recommendations.

    ERIC Educational Resources Information Center

    Child Care Information Exchange, 1991

    1991-01-01

    Describes "Day Care Nightmares," a two-part expose on ABC's PrimeTime Live, broadcast in June 1991, in which negative claims were made about the state of day care in the United States. A variety of advocates, policymakers, and child care providers present their reactions to the shows and their recommendations on what action can be taken.…

  7. Visual evoked potentials in infants exposed to methadone in utero.

    PubMed

    McGlone, L; Mactier, H; Hamilton, R; Bradnam, M S; Boulton, R; Borland, W; Hepburn, M; McCulloch, D L

    2008-09-01

    We investigated the effects of maternal drug misuse on neonatal visual evoked potentials (VEPs). Flash VEPs were recorded within 4 days of birth from 21 term infants of mothers misusing drugs and prescribed substitute methadone and 20 controls. Waveforms were classified as typical, atypical, immature or non-detectable, and amplitude and latencies were measured. VEPs from drug-exposed infants were less likely to be of typical waveform and more likely to be immature or non-detectable (p<0.01) than those of control infants. They were also smaller in amplitude (median 10.8 vs 24.4 microV, p<0.001). VEPs of drug-exposed infants had matured after 1 week but remained of lower amplitude than VEPs of newborn controls (p<0.01) and were non-detectable in 15%. Flash VEPs differ between maternal drug-exposed and non-drug-exposed newborns. Future research should address the specific effects of maternal methadone and/or other illicit drug misuse on infant VEPs, and associations between neonatal VEPs and subsequent visual development.

  8. 9 CFR 78.32 - Brucellosis exposed swine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Brucellosis exposed swine. 78.32 Section 78.32 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS...

  9. Structural brain changes in prenatal methamphetamine-exposed children.

    PubMed

    Roos, Annerine; Jones, Gaby; Howells, Fleur M; Stein, Dan J; Donald, Kirsten A

    2014-06-01

    The global use of methamphetamine (MA) has increased substantially in recent years, but the effect of MA on brain structure in prenatally exposed children is understudied. Here we aimed to investigate potential changes in brain volumes and cortical thickness of children with prenatal MA-exposure compared to unexposed controls. Eighteen 6-year old children with MA-exposure during pregnancy and 18 healthy controls matched for age, gender and socio-economic background underwent structural imaging. Brain volumes and cortical thickness were assessed using Freesurfer and compared using ANOVA. Left putamen volume was significantly increased, and reduced cortical thickness was observed in the left hemisphere of the inferior parietal, parsopercularis and precuneus areas of MA-exposed children compared to controls. Compared to control males, prenatal MA-exposed males had greater volumes in striatal and associated areas, whereas MA-exposed females predominantly had greater cortical thickness compared to control females. In utero exposure to MA results in changes in the striatum of the developing child. In addition, changes within the striatal, frontal, and parietal areas are in part gender dependent.

  10. 43. Interior view, east study window from the parlor. Exposed ...

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

    43. Interior view, east study window from the parlor. Exposed areas above and to the left of the window show remnants of decorative painting believed to date from early in the nineteenth century. - John Bartram House & Garden, House, 54th Street & Lindbergh Boulevard, Philadelphia, Philadelphia County, PA

  11. Embryo- and fetotoxicity of chromium in pregestationally exposed mice

    SciTech Connect

    Junaid, M.; Murthy, R.C.; Saxena, D.K.

    1996-10-01

    Chromium, an essential element in the human body required for proper carbohydrate, protein, and fat metabolism, is reported to impair gestational development of offspring of workers chronically exposed to this metal in the work place. Workers in chromium based industries can be exposed to concentrations two orders of magnitude higher than the general population. Among the general population, residents living near chromate production sites may be exposed to high levels of chromium (VI) in air or to elevated levels (40 - 50,000 ppm) of chromium in effluents. Shmitova reported afterbirth and puerperal hemorrhages in women industrially exposed to this metal and observed high chromium levels in blood and urine of pregnant women and in fetal and cord blood. Chromium readily passes the placental barrier and reaches the growing fetus. Exposure of mice to chromium during various gestational periods resulted in embryo and fetotoxic effects. This study looks at the role of body chromium accumulated pregestationally on embryo and fetal development and its subsequent transfer to feto-placental sites. 25 refs., 3 tabs.

  12. Out-of-Home Placement of Children Exposed to Violence

    ERIC Educational Resources Information Center

    Harpaz-Rotem, Ilan; Berkowitz, Steven; Marans, Steven; Murphy, Robert A.; Rosenheck, Robert A.

    2008-01-01

    There is growing concern about the increasing number of children in the USA who are exposed to community violence and the need to remove some of them from their families. This study examines risk factors for out-of-home placement among a large pool of children and adolescents who were referred for general clinical assessment following exposure to…

  13. TRANSCRIPTIONAL RESPONSES OF MOUSE EMBRYO CULTURES EXPOSED TO BROMOCHLOROACETIC ACID

    EPA Science Inventory

    Transcriptional responses of mouse embryo cultures exposed to bromochloroacetic acid

    Edward D. Karoly?*, Judith E. Schmid* and E. Sidney Hunter III*
    ?Curriculum in Toxicology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina and *Reproductive Tox...

  14. PBF detail of metal pedestrian bridge over exposed control cables, ...

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

    PBF detail of metal pedestrian bridge over exposed control cables, which run between Control (PER-619) and Reactor Buildings (PER-620). Camera facing northwest. Southwest corner of PER-620 at upper right of view. Date: May 2004. INEEL negative no. HD-41-6-3 - Idaho National Engineering Laboratory, SPERT-I & Power Burst Facility Area, Scoville, Butte County, ID

  15. Biological responses of marine flatfish exposed to municipal wastewater effluent.

    PubMed

    Vidal-Dorsch, Doris E; Bay, Steven M; Greenstein, Darrin J; Baker, Michael E; Hardiman, Gary; Reyes, Jesus A; Kelley, Kevin M; Schlenk, Daniel

    2014-03-01

    There is increasing concern over the presence of pharmaceutical compounds, personal care products, and other chemicals collectively known as contaminants of emerging concern (CECs) in municipal effluents, yet knowledge of potential environmental impacts related to these compounds is still limited. The present study used laboratory exposures to examine estrogenic, androgenic, and thyroid-related endocrine responses in marine hornyhead turbot (Pleuronichthys verticalis) exposed to CECs from municipal effluents with 2 degrees of treatment. Fish were exposed for 14 d to environmentally realistic concentrations of effluent (0.5%) and to a higher concentration (5%) to investigate dose responses. Plasma concentrations of estradiol (E2), vitellogenin (VTG), 11-keto testosterone, and thyroxine were measured to assess endocrine responses. Contaminants of emerging concern were analyzed to characterize the effluents. Diverse types of effluent CECs were detected. Statistically significant responses were not observed in fish exposed to environmentally realistic concentrations of effluent. Elevated plasma E2 concentrations were observed in males exposed to ammonia concentrations similar to those found in effluents. However, exposure to ammonia did not induce VTG production in male fish. The results of the present study highlight the importance of conducting research with sentinel organisms in laboratory studies to understand the environmental significance of the presence of CECs in aquatic systems.

  16. Charging time for dust grain on surface exposed to plasma

    SciTech Connect

    Sheridan, T. E.

    2013-04-14

    We consider the charging of a dust grain sitting on a surface exposed to plasma. The stochastic model of Sheridan and Hayes [Appl. Phys. Lett. 98, 091501 (2011)] is solved analytically for the charging time, which is found to be directly proportional to the square root of the electron temperature and inversely proportional to both the grain radius and plasma density.

  17. 18. William E. Barrett, Photographer, August 1975. EXPOSED VIEW OF ...

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

    18. William E. Barrett, Photographer, August 1975. EXPOSED VIEW OF LOWER PULLEYS OF LEFT-HAND MILL. LOWER LEFT IS BAND SAW PULLEY. UPPER LEFT IS TENSION WHEEL. LARGE PULLEY ON RIGHT IS DRIVE WHEEL FROM POWER SOURCE. - Meadow River Lumber Company, Highway 60, Rainelle, Greenbrier County, WV

  18. A pill to treat people exposed to radioactive materials

    ScienceCinema

    Abergel, Rebecca

    2016-07-12

    Berkeley Lab's Rebecca Abergel discusses "A pill to treat people exposed to radioactive materials" in this Oct. 28, 2013 talk, which is part of a Science at the Theater event entitled Eight Big Ideas. Go here to watch the entire event with all 8 speakers:

  19. RESPIRATORY DAMAGE IN CHILDREN EXPOSED TO URBAN POLLUTION

    EPA Science Inventory


    Southwest Metropolitan Mexico City (SWMMC) children are chronically exposed to complex mixtures of air pollutants. In a cross-sectional arm of our study, we investigated the association between exposure to SWMMC atmosphere and nasal abnormalities, hyperinflation, and intersti...

  20. Induction of alopecia in mice exposed to cigarette smoke.

    PubMed

    D'Agostini, F; Balansky, R; Pesce, C; Fiallo, P; Lubet, R A; Kelloff, G J; De Flora, S

    2000-04-03

    Besides being responsible for a high proportion of those chronic degenerative diseases that are the leading causes of death in the population, tobacco smoking has been associated with skin diseases. Smoke genotoxicants are metabolized in hair follicle cells, where they form DNA adducts and cause DNA damage. The suspicion was raised that, in humans, a link may exist between smoking and both premature grey hair and hair loss. In order to check this hypothesis, we carried out a study in C57BL/6 mice exposed whole-body to a mixture of sidestream and mainstream cigarette smoke. After 3 months exposure, most mice developed areas of alopecia and grey hair, while no such lesions occurred either in sham-exposed mice or in smoke-exposed mice receiving the chemopreventive agent N-acetylcysteine with drinking water. Cell apoptosis occurred massively in the hair bulbs at the edge of alopecia areas. Smoke-exposed mice had extensive atrophy of the epidermis, reduced thickness of the subcutaneous tissue, and scarcity of hair follicles. On the whole, exposure to smoke genotoxic components appears to alter the hair cycle with a dystrophic anagen pattern. Although this mechanism is different from that of genotoxic cytostatic drugs, N-acetylcysteine appears to exert protective effects in both conditions.

  1. Profiles of Reactivity in Cocaine-Exposed Children

    ERIC Educational Resources Information Center

    Schuetze, Pamela; Molnar, Danielle S.; Eiden, Rina D.

    2012-01-01

    This study explored the possibility that specific, theoretically consistent profiles of reactivity could be identified in a sample of cocaine-exposed infants and whether these profiles were associated with a range of infant and/or maternal characteristics. Cluster analysis was used to identify distinct groups of infants based on physiological,…

  2. 18. INTERIOR OF ROOM 106 LOOKING SOUTHEAST. EXPOSED BEAM AT ...

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

    18. INTERIOR OF ROOM 106 LOOKING SOUTHEAST. EXPOSED BEAM AT CEILING IS PAINTED. FLOOR IS VINYL COMPOSITION TILE. WALLS AND CEILING ARE PAINTED GYPSUM BOARD. - Presidio of San Francisco, Cavalry Stables, Cowles Street, between Lincoln Boulevard & McDowell Street, San Francisco, San Francisco County, CA

  3. Preventing Alcohol-Exposed Pregnancy among American-Indian Youth

    ERIC Educational Resources Information Center

    Jensen, Jamie; Kenyon, DenYelle Baete; Hanson, Jessica D.

    2016-01-01

    Research has determined that the prevention of alcohol-exposed pregnancies (AEP) must occur preconceptually, either by reducing alcohol intake in women planning pregnancy or at risk for becoming pregnant, or by preventing pregnancy in women drinking at risky levels. One such AEP prevention programme with non-pregnant American-Indian (AI) women is…

  4. Detail, oblique view to northeast atop building 935 showing exposed ...

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

    Detail, oblique view to northeast atop building 935 showing exposed roof sections of buildings 934 (center) and 933 (left), 90 mm lens. - Travis Air Force Base, Nuclear Weapons Assembly Plant 3, W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  5. Genetic Predisposition for Dermal Problems in Hexavalent Chromium Exposed Population

    PubMed Central

    Sharma, Priti; Bihari, Vipin; Agarwal, Sudhir K.; Goel, Sudhir K.

    2012-01-01

    We studied the effect of genetic susceptibility on hexavalent chromium induced dermal adversities. The health status of population was examined from the areas of Kanpur (India) having the elevated hexavalent chromium levels in groundwater. Blood samples were collected for DNA isolation to conduct polymorphic determination of genes, namely: NQO1 (C609T), hOGG1 (C1245G), GSTT1, and GSTM1 (deletion). Symptomatic exposed subjects (n = 38) were compared with asymptomatic exposed subjects (n = 108) along with asymptomatic controls (n = 148) from a non contaminated reference community. Exposed symptomatic group consisted of 36.8% subjects who were GSTM1 null genotyped as compared to asymptomatic where only 19.4% subjects were null. The exposed subjects with GSTM1 null genotype were more susceptible to dermal adversities in comparison with wild genotyped subjects (OR = 2.42; 95% CI = 1.071–5.451). Age, smoking, gender or duration of residence were not found to have any confounding effect towards this association. Association with other genes was not statistically significant, nonetheless, possible contribution by these genes cannot be ruled out. In conclusion, variation in the polymorphic status of GSTM1 gene may influence dermal outcomes among residents from Cr(VI) contaminated areas. Further studies are therefore, needed to examine these observations among different population groups. PMID:22919465

  6. 15. A CLOSE UP VIEW OF ONE OF THE EXPOSED ...

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

    15. A CLOSE UP VIEW OF ONE OF THE EXPOSED AGGREGATE LAMP STANDARDS, ITS BRONZE DECORATED FERRULE AND BRONZE LENS RECEIVER. - County Line Bridge, Spanning St. Joseph River at State Route 219, 0.6 mile south of U.S. Route 20, Osceola, St. Joseph County, IN

  7. Semen study of papaya workers exposed to ethylene dibromide

    SciTech Connect

    Ratcliffe, J.M.; Schrader, S.M.; Steenland, K.; Clapp, D.; Turner, T.

    1984-01-01

    A cross sectional semen and cytogenetic study was performed on male workers exposed to ethylene-dibromide (EDB) in the papaya fumigation industry in Hawaii. Semen analyses were conducted on 46 men in six fumigation facilities with an average length of employment of 5 years and airborne exposures to EDB ranging from 16 to 213 parts per billion. Statistically significant decreases in sperm count per ejaculate and the percentage of viable and motile sperm and increases in the proportion of specific morphological abnormalities were observed among exposed men when compared with controls. Semen volume and sperm concentration were also lower in the exposed group. No effect of exposure to EDB on sperm velocity, the overall proportion of sperm with normal morphology or YFF bodies was noted. The authors conclude that based on the decreases in sperm count, viability and motility and increases in certain types of morphological abnormalities among workers exposed to EDB, EDB may increase the risk of reproductive impairment in workers at exposure levels near the NIOSH recommended limit of 45 parts per billion and far below the current OSHA standard of 20 parts per million.

  8. A Care Coordination Program for Substance-Exposed Newborns

    ERIC Educational Resources Information Center

    Twomey, Jean E.; Caldwell, Donna; Soave, Rosemary; Fontaine, Lynne Andreozzi; Lester, Barry M.

    2011-01-01

    The Vulnerable Infants Program of Rhode Island (VIP-RI) was established as a care coordination program to promote permanency for substance-exposed newborns in the child welfare system. Goals of VIP-RI were to optimize parents' opportunities for reunification and increase the efficacy of social service systems involved with families affected by…

  9. Multidimensional Resilience in Urban Children Exposed to Community Violence.

    ERIC Educational Resources Information Center

    O'Donnell, Deborah A.; Schwab-Stone, Mary E.; Muyeed, Adaline Z.

    2002-01-01

    This study examined how parent, school, and peer support differentially affected resilience among urban sixth-, eighth-, and tenth-graders. Findings indicated that both parent and school support factors positively related to resilience in children who had been exposed to community violence; however, peer support negatively related to resilience in…

  10. Proteomic Profiling of Bladders from Mice Exposed with Sodium Arsenite

    EPA Science Inventory

    Arsenic, an environmental contaminant, has been linked with cancer of the bladder in humans. To study the mode of action of arsenic, female CH3 mice were exposed to 85 ppm sodium arsenite in their drinking water for 30 days. Following the exposure a comparative proteomic analysis...

  11. 29. VIEW WEST TOWARDS KALAWAO OF PIPELINE, EXPOSED AT LOWER ...

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

    29. VIEW WEST TOWARDS KALAWAO OF PIPELINE, EXPOSED AT LOWER LEFT. CAT TRACKS, MADE BY THE CONSTRUCTION/MAINTENANCE VEHICLES, CAN BE SEEN ALONG BOULDER BEACH - Kalaupapa Water Supply System, Waikolu Valley to Kalaupapa Settlement, Island of Molokai, Kalaupapa, Kalawao County, HI

  12. Behavioural evaluation of workers exposed to mixtures of organic solvents.

    PubMed

    Maizlish, N A; Langolf, G D; Whitehead, L W; Fine, L J; Albers, J W; Goldberg, J; Smith, P

    1985-09-01

    Reports from Scandinavia have suggested behavioural impairment among long term workers exposed to solvents below regulatory standards. A cross sectional study of behavioural performance was conducted among printers and spray painters exposed to mixtures of organic solvents to replicate the Scandinavian studies and to examine dose-response relationships. Eligible subjects consisted of 640 hourly workers from four midwestern United States companies. Of these, 269 responded to requests to participate and 240 were selected for study based on restrictions for age, sex, education, and other potentially confounding variables. The subjects tested had been employed on average for six years. Each subject completed an occupational history, underwent a medical examination, and completed a battery of behavioural tests. These included the Fitts law psychomotor task, the Stroop colour-word test, the Sternberg short term memory scanning test, the short term memory span test, and the continuous recognition memory test. Solvent exposure for each subject was defined as an exposed or non-exposed category based on a plant industrial hygiene walk-through and the concentration of solvents based on an analysis of full shift personal air samples by gas chromatography. The first definition was used to maintain consistency with Scandinavian studies, but the second was considered to be more accurate. The average full shift solvent concentration was 302 ppm for the printing plant workers and 6-13 ppm for the workers at other plants. Isopropanol and hexane were the major components, compared with toluene in Scandinavian studies. Performance on behavioural tests was analysed using multiple linear regression with solvent concentration as an independent variable. Other relevant demographic variables were also considered for inclusion. No significant (p greater than 0.05) relation between solvent concentration and impairment on any of the 10 behavioural variables was observed after controlling for

  13. Behavioural evaluation of workers exposed to mixtures of organic solvents.

    PubMed Central

    Maizlish, N A; Langolf, G D; Whitehead, L W; Fine, L J; Albers, J W; Goldberg, J; Smith, P

    1985-01-01

    Reports from Scandinavia have suggested behavioural impairment among long term workers exposed to solvents below regulatory standards. A cross sectional study of behavioural performance was conducted among printers and spray painters exposed to mixtures of organic solvents to replicate the Scandinavian studies and to examine dose-response relationships. Eligible subjects consisted of 640 hourly workers from four midwestern United States companies. Of these, 269 responded to requests to participate and 240 were selected for study based on restrictions for age, sex, education, and other potentially confounding variables. The subjects tested had been employed on average for six years. Each subject completed an occupational history, underwent a medical examination, and completed a battery of behavioural tests. These included the Fitts law psychomotor task, the Stroop colour-word test, the Sternberg short term memory scanning test, the short term memory span test, and the continuous recognition memory test. Solvent exposure for each subject was defined as an exposed or non-exposed category based on a plant industrial hygiene walk-through and the concentration of solvents based on an analysis of full shift personal air samples by gas chromatography. The first definition was used to maintain consistency with Scandinavian studies, but the second was considered to be more accurate. The average full shift solvent concentration was 302 ppm for the printing plant workers and 6-13 ppm for the workers at other plants. Isopropanol and hexane were the major components, compared with toluene in Scandinavian studies. Performance on behavioural tests was analysed using multiple linear regression with solvent concentration as an independent variable. Other relevant demographic variables were also considered for inclusion. No significant (p greater than 0.05) relation between solvent concentration and impairment on any of the 10 behavioural variables was observed after controlling for

  14. Exposed Ice in the Northern Mid-Latitudes of Mars

    NASA Technical Reports Server (NTRS)

    Allen, Carlton C.

    2007-01-01

    Ice-Rich Layer: Polygonal features with dimensions of approximately 100 meters, bounded by cracks, are commonly observed on the martian northern plains. These features are generally attributed to thermal cracking of ice-rich sediments, in direct analogy to polygons in terrestrial polar regions. We mapped polygons in the northern mid-latitudes (30 to 65 N) using MOC and HiRISE images. Polygons are scattered across the northern plains, with a particular concentration in western Utopia Planitia. This region largely overlaps the Late Amazonian Astapus Colles unit, characterized by polygonal terrain and nested pits consistent with periglacial and thermokarst origins. Bright and Dark Polygonal Cracks: An examination of all MOC images (1997 through 2003) covering the study area demonstrated that, at latitudes of 55 to 65 N, most of the imaged polygons show bright bounding cracks. We interpret these bright cracks as exposed ice. Between 40 and 55 N, most of the imaged polygons show dark bounding cracks. These are interpreted as polygons from which the exposed ice has been removed by sublimation. The long-term stability limit for exposed ice, even in deep cracks, apparently lies near 55 N. Bright and Dark Spots: Many HiRISE and MOC frames showing polygons in the northern plains also show small numbers of bright and dark spots, particularly in western Utopia Planitia. Many of the spots are closely associated with collapse features suggestive of thermokarst. The spots range from tens to approximately 100 meters in diameter. The bright spots are interpreted as exposed ice, due to their prevalence on terrain mapped as ice rich. The dark spots are interpreted as former bright spots, which have darkened as the exposed ice is lost by sublimation. The bright spots may be the martian equivalents of pingos, ice-cored mounds found in periglacial regions on Earth. Terrestrial pingos from which the ice core has melted often collapse to form depressions similar to the martian dark spots

  15. Epidemiological survey of workers exposed to inorganic germanium compounds

    PubMed Central

    Swennen, B; Mallants, A; Roels, H; Buchet, J; Bernard, A; Lauwerys, R; Lison, D

    2000-01-01

    OBJECTIVES—To assess occupational exposure to inorganic germanium (Ge) in workers from a producing plant, and to assess the health of these workers, with a special focus on respiratory, kidney, and liver functions.
METHODS—Cross sectional study of 75 workers exposed to Ge and 79 matched referents. Exposure was characterised by measuring air and urine concentrations of the element during a typical working week, and health was assessed by a questionnaire, clinical examination, lung function testing, chest radiography, and clinical chemistry in serum and urine, including high and low molecular weight urinary proteins.
RESULTS—Airborne concentrations of Ge (inhalable fraction) ranged from 0.03 to 300 µg/m, which was reflected by increased urinary excretion of Ge (0.12-200 µg/g creatinine, after the shift at the end of the working week). Lung, liver, and haematological variables were not significantly different between referents and workers exposed to Ge. A slightly higher urinary concentration of high molecular weight proteins (albumin and transferrin) was found in workers exposed to Ge, possibly reflecting subclinical glomerular changes. No relation was found between the intensity or duration of exposure and the urinary concentration of albumin. No difference between referents and workers exposed to Ge was found for other renal variables.
CONCLUSIONS—Measurement of urinary Ge can detect occupational exposure to inorganic Ge and its compounds. It is prudent to recommend the monitoring of renal variables in workers exposed to Ge.


Keywords: inorganic germanium; occupational exposure; biological monitoring PMID:10810110

  16. Measurement of DNA repair deficiency in workers exposed to benzene

    SciTech Connect

    Hallberg, L.M.; Au, W.W.; El Zein, R.; Grossman, L.

    1996-05-01

    We hypothesize that chronic exposure to environmental toxicants can induce genetic damage causing DNA repair deficiencies and leading to the postulated mutator phenotype of carcinogenesis. To test our hypothesis, a host cell reactivation (HCR) assay was used in which pCMVcat plasmids were damaged with UV light (175, 350 J/m{sup 2} UV light), inactivating the chloramphenicol acetyltransferase reporter gene, and then transfected into lymphocytes. Transfected lymphocytes were therefore challenged to repair the damaged plasmids, reactivating the reporter gene. Xeroderma pigmentosum (XP) and Gaucher cell lines were used as positive and negative controls for the HCR assay. The Gaucher cell line repaired normally but XP cell lines demonstrated lower repair activity. Additionally, the repair activity of the XP heterozygous cell line showed intermediate repair compared to the homozygous XP and Gaucher cells. We used HCR to measure the effects of benzene exposure on 12 exposed and 8 nonexposed workers from a local benzene plant. Plasmids 175 J/m{sup 2} and 350 J/m{sup 2} were repaired with a mean frequency of 66% and 58%, respectively, in control workers compared to 71% and 62% in exposed workers. Conversely, more of the exposed workers were grouped into the reduced repair category than controls. These differences in repair capacity between exposed and control workers were, however, not statistically significant. The lack of significant differences between the exposed and control groups may be due to extremely low exposure to benzene (<0.3 ppm), small population size, or a lack of benzene genotoxicity at these concentrations. These results are consistent with a parallel hprt gene mutation assay. 26 refs., 4 figs., 2 tabs.

  17. Sperm shape abnormalities in carbaryl-exposed employees

    PubMed Central

    Wyrobek, A. J.; Watchmaker, G.; Gordon, L.; Wong, K.; Moore, D.; Whorton, D.

    1981-01-01

    Semen was collected from 50 men occupationally exposed to carbaryl (1-naphthyl methyl carbamate) in a produciton plant for durations of 1 to 18 years and compared to semen from a control group of 34 unexposed, newly-hired workers. Employment, fertility, health, personal data, and blood samples were collected for each individual. Semen samples were analyzed for changes in sperm count, morphology, and frequency of sperm carrying double flourescent bodies (YFF). As a group, the exposed workers showed a significantly higher proportion of sperm with abnormal head shapes than did the control group (p < 0.005). Age, smoking habits, and medical problems did not appear to affect this result. This finding appears to be limited to men working in the carbaryl production area at the time of sampling. Sperm count and YFF did not show similar differences, which may be because they are known to be statistically less sensitive to small changes. Formerly exposed workers (away from carbaryl for an average of 6.3 years) showed a marginally significant elevation in sperm abnormalities compared to controls (p < .05, one-tailed statistical analyses) suggesting that the increase in abnormal morphology may not be reversible. However, the question of reversibility is sensitive to confounding factors and small sample sizes and, therefore, requires further study. With these data a definitive link between carbaryl exposure and human seminal defects cannot be established. Although a distinct effect on sperm morphology was seen in the exposed group, the increases in sperm shape abnormalities were not related to exposure dose (estimated by number of years on the job or job classification during the year prior to semen collection). Inexplicably, the increases in sperm abnormalities were seen primarily in currently exposed men who had worked with carbaryl for less than approximately 6 years. These findings suggest the need for further study since other workplace-related factor(s) may be responsible

  18. Chromosome aberration and lipid peroxidation in chromium-exposed workers.

    PubMed

    Maeng, S H; Chung, H W; Kim, K J; Lee, B M; Shin, Y C; Kim, S J; Yu, I J

    2004-01-01

    Chromosome aberration frequency and lipid peroxidation levels were analyzed to investigate their efficacy as biological markers for monitoring the genotoxicity and oxidative damage in Korean chromium (Cr)-exposed workers. Fifty-one Cr-exposed workers and 31 age-matched controls in ten chrome-plating plants were sampled. The Cr level was measured in the workers' blood and urine, and in the ambient air at the workplaces. The conventional Giemsa staining method and fluorescence in situ hybridization (FISH) technique were used for chromosome aberration analysis. Spectrum green whole chromosome paint specific for chromosome 4 was used in the FISH procedure. As for lipid peroxidation, malondialdehyde (MDA) was measured in the blood plasma as thiobarbituric acid-reactive substances (TBARS). The blood Cr concentration was statistically correlated with both the frequency of chromatid exchange and the total frequency of chromosome/chromatid breaks and exchanges, as detected by the Giemsa staining. Meanwhile, the frequency of translocation, as detected by the FISH technique, was significantly higher in the Cr-exposed workers than in the controls and it correlated with the blood Cr concentration. Although the concentration of MDA, the metabolite of lipid peroxidation, in the exposed workers was higher than that of the controls, no statistically significant correlation between the MDA level and the blood or urine Cr levels was observed. Accordingly, the genotoxicity and oxidative damage (plasma lipid peroxidation) in the Korean Cr-exposed workers were consequential at quite low exposure levels, plus chromosome rearrangement, especially translocation, was clearly evident as a biological response marker for Cr exposure based on a significant positive correlation between the translocations detected by FISH and the Cr in the blood.

  19. The AMINO experiment: a laboratory for astrochemistry and astrobiology on the EXPOSE-R facility of the International Space Station

    NASA Astrophysics Data System (ADS)

    Cottin, H.; Saiagh, K.; Guan, Y. Y.; Cloix, M.; Khalaf, D.; Macari, F.; Jérome, M.; Polienor, J.-M.; Bénilan, Y.; Coll, P.; Fray, N.; Gazeau, M.-C.; Raulin, F.; Stalport, F.; Carrasco, N.; Szopa, C.; Bertrand, M.; Chabin, A.; Westall, F.; Vergne, J.; Da Silva, L. A.; Maurel, M.-C.; Chaput, D.; Demets, R.

    2015-01-01

    The study of the evolution of organic matter subjected to space conditions, and more specifically to Solar photons in the vacuum ultraviolet range (120-200 nm) has been undertaken in low-Earth orbit since the 1990s, and implemented on various space platforms. This paper describes a photochemistry experiment called AMINO, conducted during 22 months between 2009 and 2011 on the EXPOSE-R ESA facility, outside the International Space Station. Samples with relevance to astrobiology (connected to comets, carbonaceous meteorites and micrometeorites, the atmosphere of Titan and RNA world hypothesis) have been selected and exposed to space environment. They have been analysed after return to the Earth. This paper is not discussing the results of the experiment, but rather gives a general overview of the project, the details of the hardware used, its configuration and recent developments to enable long-duration exposure of gaseous samples in tight closed cells enabling for the first time to derive quantitative results from gaseous phase samples exposed in space.

  20. Exposed tibial bone after burns: Flap reconstruction versus dermal substitute.

    PubMed

    Verbelen, Jozef; Hoeksema, Henk; Pirayesh, Ali; Van Landuyt, Koenraad; Monstrey, Stan

    2016-03-01

    A 44 years old male patient had suffered extensive 3rd degree burns on both legs, undergoing thorough surgical debridement, resulting in both tibias being exposed. Approximately 5 months after the incident he was referred to the Department of Plastic and Reconstructive Surgery of the University Hospital Gent, Belgium, to undergo flap reconstruction. Free flap surgery was performed twice on both lower legs but failed on all four occasions. In between flap surgery, a dermal substitute (Integra(®)) was applied, attempting to cover the exposed tibias with a layer of soft tissue, but also without success. In order to promote the development of granulation tissue over the exposed bone, small holes were drilled in both tibias with removal of the outer layer of the anterior cortex causing the bone to bleed and subsequently negative pressure wound therapy (NPWT) was applied. The limited granulation tissue resulting from this procedure was then covered with a dermal substitute (Glyaderm(®)), consisting of acellular human dermis with an average thickness of 0.25mm. This dermal substitute was combined with a NPWT-dressing, and then served as an extracellular matrix (ECM), guiding the distribution of granulation tissue over the remaining areas of exposed tibial bone. Four days after initial application of Glyaderm(®) combined with NPWT both tibias were almost completely covered with a thin coating of soft tissue. In order to increase the thickness of this soft tissue cover two additional layers of Glyaderm(®) were applied at intervals of approximately 1 week. One week after the last Glyaderm(®) application both wounds were autografted. The combination of an acellular dermal substitute (Glyaderm(®)) with negative pressure wound therapy and skin grafting proved to be an efficient technique to cover a wider area of exposed tibial bone in a patient who was not a candidate for free flap surgery. An overview is also provided of newer and simpler techniques for coverage of

  1. Mechanisms of gas precipitation in plasma-exposed tungsten

    SciTech Connect

    R. D. Kolasinski; D. F. Cowgill; D. C. Donovan; M. Shimada

    2012-05-01

    Precipitation in subsurface bubbles is a key process that governs how hydrogen isotopes migrate through and become trapped within plasma-exposed tungsten. We describe a continuum-scale model of hydrogen diffusion in plasma-exposed materials that includes the effects of precipitation. The model can account for bubble expansion via dislocation loop punching, using an accurate equation of state to determine the internal pressure. This information is used to predict amount of hydrogen trapped by bubbles, as well as the conditions where the bubbles become saturated. In an effort to validate the underlying assumptions, we compare our results with published positron annihilation and thermal desorption spectroscopy data, as well as our own measurements using the tritium plasma experiment (TPE).

  2. Recovering badly exposed objects from digital photos using internet images

    NASA Astrophysics Data System (ADS)

    Savoy, Florian M.; Vonikakis, Vassilios; Winkler, Stefan; Süsstrunk, Sabine

    2014-03-01

    In this paper we consider the problem of clipped-pixel recovery over an entire badly exposed image region, using two correctly exposed images of the scene that may be captured under different conditions. The first reference image is used to recover texture; feature points are extracted along the boundaries of both the source and reference regions, while a warping function deforms the reference region to fit inside the source. The second reference is used to recover color by replacing the mean and variance of the texture reference image with those of the color reference. A user study conducted with both modified and original images demonstrates the benefits of our method. The results show that a majority of the enhanced images look natural and are preferred to the originals.

  3. Temperature increase in the fetus exposed to UHF RFID readers.

    PubMed

    Fiocchi, Serena; Parazzini, Marta; Liorni, Ilaria; Samaras, Theodoros; Ravazzani, Paolo

    2014-07-01

    Exposure to electromagnetic fields (EMFs) has prominently increased during the last decades due to the rapid development of new technologies. Among the various devices emitting EMFs, those based on Radio-frequency identification (RFID) technologies are used in all aspects of everyday life, and expose people unselectively. This scenario could pose a potential risk for some groups of the general population, such as pregnant women, who are expected to be possibly more sensitive to the thermal effects produced by EMF exposure. This is the first paper that addresses the estimation of temperature rise in two pregnant women models exposed to ultrahigh frequency RFID by computational techniques. Results show that the maximum temperature increase of the fetus and of the pregnancy-related tissues is relatively high (even about 0.7 °C), not too far from the known threshold of biological effects. However, this increase is confined to a small volume in the tissues.

  4. HSP70 expression in Biomphalaria glabrata snails exposed to cadmium.

    PubMed

    da Silva Cantinha, Rebeca; Borrely, Sueli Ivone; Oguiura, Nancy; de Bragança Pereira, Carlos Alberto; Rigolon, Marcela M; Nakano, Eliana

    2017-06-01

    In this study, the effects of the heavy metal cadmium on the stress protein HSP70 are investigated in freshwater mollusks Biomphalaria glabrata. Adult snails were exposed for 96h to CdCl2 at concentrations ranging from 0.09 to 0.7mgL(-1) (LC50/96h=0.34 (0.30-0.37). Time and concentration-dependent increases in the expression of HSP70 were observed at sub-lethal levels in the immunoblotting assay. Further, an increased survival to a lethal heat shock was observed in animals pre-exposed to a nonlethal concentration of cadmium, evidencing the induction of acquired tolerance. The present study demonstrated the inducibility of B. glabrata HSP70 by cadmium, a relevant environmental contaminant, at non-lethal levels, providing evidences that the assessment of HSP70 in B. glabrata can be regarded as a suitable biomarker for ecotoxicological studies.

  5. Profiles of Reactivity in Cocaine-Exposed Children

    PubMed Central

    Schuetze, Pamela; Molnar, Danielle S.; Eiden, Rina D.

    2012-01-01

    This study explored the possibility that specific, theoretically consistent profiles of reactivity could be identified in a sample of cocaine-exposed infants and whether these profiles were associated with a range of infant and/or maternal characteristics. Cluster analysis was used to identify distinct groups of infants based on physiological, behavioral and maternal reported measures of reactivity. Five replicable clusters were identified which corresponded to 1) Dysregulated/High Maternal Report Reactors, 2) Low Behavioral Reactors, 3) High Reactors, 4) Optimal Reactors and 5) Dysregulated/Low Maternal Report Reactors. These clusters were associated with differences in prenatal cocaine exposure status, birthweight, maternal depressive symptoms, and maternal negative affect during mother-infant interactions. These results support the presence of distinct reactivity profiles among high risk infants recruited on the basis of prenatal cocaine exposure and demographically similar control group infants not exposed to cocaine. PMID:23204615

  6. Timing of optical maturation of recently exposed material on Ceres

    NASA Astrophysics Data System (ADS)

    Schmedemann, Nico; Kneissl, T.; Neesemann, A.; Stephan, K.; Jaumann, R.; Krohn, K.; Michael, G. G.; Matz, K. D.; Otto, K. A.; Raymond, C. A.; Russell, C. T.

    2016-12-01

    On Ceres, multispectral imaging data from the Dawn spacecraft show a distinct bluish characteristic for recently exposed material from the subsurface in, for example, crater ejecta. Ejecta blankets of presumably old craters show a more reddish spectrum. We selected areas in which fresh material from the Cerean subsurface was exposed at a specific time in the past, and no later geologic process is expected to have changed its surface composition or its cratering record. For each area, we determined two color ratios and the crater retention age. The measured color ratios show an exponential diminishment of the bluish characteristic over time. Although the cause of the color change remains uncertain, the time-dependent change in spectral properties is evident, which could help identify the process.

  7. Skin friction measurement with partially exposed polymer dispersed liquid crystals

    NASA Technical Reports Server (NTRS)

    Parmar, D. S.; Holmes, H. K.

    1993-01-01

    Partially exposed polymer dispersed liquid crystal thin film (10-25 microns) deposited on a flat glass substrate has been used for the first time to measure skin friction. Utilizing the shear-stress-induced director reorientation in the partially exposed liquid-crystal droplets, optical transmission under crossed polarization has been measured as a function of the air flow differential pressure. Direct measurement of the skin friction with a skin friction drag balance, under the same aerodynamic conditions, lets us correlate the skin friction with optical transmission. This provides a unique technique for the direct measurement of skin friction from the transmitted light intensity. The results are in excellent agreement with the model suggested in this paper.

  8. Laser-induced fluorescence of space-exposed polyurethane

    NASA Technical Reports Server (NTRS)

    Hill, Ralph H., Jr.

    1993-01-01

    The object of this work was to utilize laser-induced fluorescence technique to characterize several samples of space-exposed polyurethane. These samples were flown on the Long Duration Exposure Facility (LDEF), which was in a shuttle-like orbit for nearly 6 years. Because of our present work to develop laser-induced-fluorescence inspection techniques for polymers, space-exposed samples and controls were lent to us for evaluation. These samples had been attached to the outer surface of LDEF; therefore, they were subjected to thermal cycling, solar ultraviolet radiation, vacuum, and atomic oxygen. It is well documented that atomic oxygen and ultraviolet exposure have detrimental effects on many polymers. This was a unique opportunity to make measurements on material that had been naturally degraded by an unusual environment. During our past work, data have come from artificially degraded samples and generally have demonstrated a correlation between laser-induced fluorescence and tensile strength or elasticity.

  9. Immunogenicity of Hepatitis B Vaccine in HIV Exposed Uninfected Infants.

    PubMed

    Singh, Dharmendra K; Kumar, Rajnish; Rai, Ruchi; Maurya, Manisha; Bhargava, Anudita

    2016-02-01

    There is paucity of knowledge about the immunogenicity of vaccines in infants who have been exposed to HIV in-utero but have remained uninfected. The authors studied the immunogenicity of 3 doses of recombinant hepatitis B vaccine at 6,10,14 wk of age in HIV exposed but uninfected (HEU) infants. After 3 mo of last dose of the vaccine, out of 26 infants, 23 (89.5 %) infants were found to be responders (Anti HBs IgG titres ≥ 10 mIU/ml) and 3 (11.5 %) babies remained non responders (Anti HBs IgG titres < 10 mIU/ml). The proportion of babies who were non responders were higher when compared to similar studies done on unexposed and uninfected infants, suggesting a poorer immunogenicity of hepatitis B vaccine in these infants.

  10. Personality and psychopathological profiles in individuals exposed to mobbing.

    PubMed

    Girardi, Paolo; Monaco, Edoardo; Prestigiacomo, Claudio; Talamo, Alessandra; Ruberto, Amedeo; Tatarelli, Roberto

    2007-01-01

    Increasingly, mental health and medical professionals have been asked to assess claims of psychological harm arising from harassment at the workplace, or "mobbing." This study assessed the personality and psychopathological profiles of 146 individuals exposed to mobbing using validity, clinical, and content scales of the Minnesota Multiphasic Personality Inventory 2. Profiles and factor analyses were obtained. Two major dimensions emerged among those exposed to mobbing: (a) depressed mood, difficulty in making decisions, change-related anguish, and passive-aggressive traits (b) somatic symptoms, and need for attention and affection. This cross-sectional pilot study provides evidence that personality profiles of mobbing victims and psychological damage resulting from mobbing may be evaluated using standardized assessments, though a longitudinal study is needed to delineate cause-and-effect relationships.

  11. Work function recovery of air exposed molybdenum oxide thin films

    NASA Astrophysics Data System (ADS)

    Irfan, Irfan; James Turinske, Alexander; Bao, Zhenan; Gao, Yongli

    2012-08-01

    We report substantial work function (WF) recovery of air exposed molybdenum oxide thin films with vacuum annealing. We observed a sharp reduction in the MoOx WF (from 6.8 eV to 5.6 eV) as well as a very thin layer of oxygen rich adsorbate on the MoOx film after an hour of air exposure. The WF of the exposed MoOx film started to gradually recover with increasing annealing temperature in vacuum, and the saturation in the WF recovery was observed at 450 °C with WF ˜6.4 eV. We further studied the interface formation between the annealed MoOx and copper phthalocyanine (CuPc). The highest occupied molecular orbital (HOMO) level of CuPc was observed to be almost pinned to the Fermi level, strongly suggesting the possibility of efficient hole injection with the vacuum annealed MoOx film.

  12. Monitoring Calcium in Trout Eggs Exposed to Hydrazine.

    DTIC Science & Technology

    1981-07-10

    scoliosis , gaped mouth and downward-turned tail were induced in rainbow trout eggs exposed to hydrazine for 48 hours. Since hydrazine is capable of...the chorion was rapid and distinct. Hatched embryos or larvae showed body movements that resulted in good swimming behavior. The swimming was...Since bone growth is abnormal and the distribution of muscle forces is altered, scoliosis would be expected in a large number of treated embryos. One

  13. Occupational hypersensitivity pneumonitis in a smelter exposed to zinc fumes

    SciTech Connect

    Ameille, J.; Brechot, J.M.; Brochard, P.; Capron, F.; Dore, M.F. )

    1992-03-01

    A smelter exposed to zinc fumes reported severe recurrent episodes of cough, dyspnea and fever. Bronchoalveolar lavage showed a marked increase in lymphocytes count with predominance of CD8 T-lymphocytes. Presence of zinc in alveolar macrophages was assessed by analytic transmission electron microscopy. This is the first case of recurrent bronchoalveolitis related to zinc exposure in which the clinical picture and BAL results indicate a probable hypersensitivity pneumonitis.

  14. Toxicity of lunar dust assessed in inhalation-exposed rats

    PubMed Central

    Lam, Chiu-wing; Scully, Robert R.; Zhang, Ye; Renne, Roger A.; Hunter, Robert L.; McCluskey, Richard A.; Chen, Bean T.; Castranova, Vincent; Driscoll, Kevin E.; Gardner, Donald E.; McClellan, Roger O.; Cooper, Bonnie L.; McKay, David S.; Marshall, Linda; James, John T.

    2015-01-01

    Humans will again set foot on the moon. The moon is covered by a layer of fine dust, which can pose a respiratory hazard. We investigated the pulmonary toxicity of lunar dust in rats exposed to 0, 2.1, 6.8, 20.8 and 60.6 mg/m3 of respirable-size lunar dust for 4 weeks (6 h/day, 5 days/week); the aerosols in the nose-only exposure chambers were generated from a jet-mill ground preparation of a lunar soil collected during the Apollo 14 mission. After 4 weeks of exposure to air or lunar dust, groups of five rats were euthanized 1 day, 1 week, 4 weeks or 13 weeks after the last exposure for assessment of pulmonary toxicity. Biomarkers of toxicity assessed in bronchoalveolar fluids showed concentration-dependent changes; biomarkers that showed treatment effects were total cell and neutrophil counts, total protein concentrations and cellular enzymes (lactate dehydrogenase, glutamyl transferase and aspartate transaminase). No statistically significant differences in these biomarkers were detected between rats exposed to air and those exposed to the two low concentrations of lunar dust. Dose-dependent histopathology, including inflammation, septal thickening, fibrosis and granulomas, in the lung was observed at the two higher exposure concentrations. No lesions were detected in rats exposed to ≤6.8 mg/m3. This 4-week exposure study in rats showed that 6.8 mg/m3 was the highest no-observable-adverse-effect level (NOAEL). These results will be useful for assessing the health risk to humans of exposure to lunar dust, establishing human exposure limits and guiding the design of dust mitigation systems in lunar landers or habitats. PMID:24102467

  15. 16. INTERIOR OF ROOM 105 LOOKING TOWARD SOUTHEAST WALL. EXPOSED ...

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

    16. INTERIOR OF ROOM 105 LOOKING TOWARD SOUTHEAST WALL. EXPOSED POST EXISTS IN MIDDLE OF ROOM. A SMALL OPENING HAS BEEN CUT INTO THE UPPER PORTION OF THE SOUTHEAST WALL THROUGH TO THE ADJOINING ROOM (106). GYPSUM BOARD ON WALLS WITH WOOD TRIM, FLUORESCENT LIGHTING, AND VINYL COMPOSITION TILE ON FLOORS ARE ALL LATER ADDITIONS. - Presidio of San Francisco, Cavalry Stables, Cowles Street, between Lincoln Boulevard & McDowell Street, San Francisco, San Francisco County, CA

  16. Potential contribution of exposed resin to ecosystem emissions of monoterpenes

    NASA Astrophysics Data System (ADS)

    Eller, Allyson S. D.; Harley, Peter; Monson, Russell K.

    2013-10-01

    Conifers, especially pines, produce and store under pressure monoterpene-laden resin in canals located throughout the plant. When the plants are damaged and resin canals punctured, the resin is exuded and the monoterpenes are released into the atmosphere, a process that has been shown to influence ecosystem-level monoterpene emissions. Less attention has been paid to the small amounts of resin that are exuded from branches, expanding needles, developing pollen cones, and terminal buds in the absence of any damage. The goal of this study was to provide the first estimate of the potential of this naturally-exposed resin to influence emissions of monoterpenes from ponderosa pine (Pinus ponderosa) ecosystems. When resin is first exuded as small spherical beads from undamaged tissues it emits monoterpenes to the atmosphere at a rate that is four orders of magnitude greater than needle tissue with an equivalent exposed surface area and the emissions from exuded beads decline exponentially as the resin dries. We made measurements of resin beads on the branches of ponderosa pine trees in the middle of the growing season and found, on average, 0.15 cm2 of exposed resin bead surface area and 1250 cm2 of total needle surface area per branch tip. If the resin emerged over the course of 10 days, resin emissions would make up 10% of the ecosystem emissions each day. Since we only accounted for exposed resin at a single point in time, this is probably an underestimate of how much total resin is exuded from undamaged pine tissues over the course of a growing season. Our observations, however, reveal the importance of this previously unrecognized source of monoterpenes emitted from pine forests and its potential to influence regional atmospheric chemistry dynamics.

  17. Toxicity of lunar dust assessed in inhalation-exposed rats.

    PubMed

    Lam, Chiu-wing; Scully, Robert R; Zhang, Ye; Renne, Roger A; Hunter, Robert L; McCluskey, Richard A; Chen, Bean T; Castranova, Vincent; Driscoll, Kevin E; Gardner, Donald E; McClellan, Roger O; Cooper, Bonnie L; McKay, David S; Marshall, Linda; James, John T

    2013-10-01

    Humans will again set foot on the moon. The moon is covered by a layer of fine dust, which can pose a respiratory hazard. We investigated the pulmonary toxicity of lunar dust in rats exposed to 0, 2.1, 6.8, 20.8 and 60.6 mg/m(3) of respirable-size lunar dust for 4 weeks (6 h/day, 5 days/week); the aerosols in the nose-only exposure chambers were generated from a jet-mill ground preparation of a lunar soil collected during the Apollo 14 mission. After 4 weeks of exposure to air or lunar dust, groups of five rats were euthanized 1 day, 1 week, 4 weeks or 13 weeks after the last exposure for assessment of pulmonary toxicity. Biomarkers of toxicity assessed in bronchoalveolar fluids showed concentration-dependent changes; biomarkers that showed treatment effects were total cell and neutrophil counts, total protein concentrations and cellular enzymes (lactate dehydrogenase, glutamyl transferase and aspartate transaminase). No statistically significant differences in these biomarkers were detected between rats exposed to air and those exposed to the two low concentrations of lunar dust. Dose-dependent histopathology, including inflammation, septal thickening, fibrosis and granulomas, in the lung was observed at the two higher exposure concentrations. No lesions were detected in rats exposed to ≤6.8 mg/m(3). This 4-week exposure study in rats showed that 6.8 mg/m(3) was the highest no-observable-adverse-effect level (NOAEL). These results will be useful for assessing the health risk to humans of exposure to lunar dust, establishing human exposure limits and guiding the design of dust mitigation systems in lunar landers or habitats.

  18. Genetic damage in subjects exposed to radiofrequency radiation.

    PubMed

    Verschaeve, Luc

    2009-01-01

    Despite many research efforts and public debate there is still great concern about the possible adverse effects of radiofrequency (RF) radiation on human health. This is especially due to the enormous increase of wireless mobile telephones and other telecommunication devices throughout the world. The possible genetic effects of mobile phone radiation and other sources of radiofrequencies constitute one of the major points of concern. In the past several review papers were published on laboratory investigations that were devoted to in vitro and in vivo animal (cyto)genetic studies. However, it may be assumed that some of the most important observations are those obtained from studies with individuals that were exposed to relatively high levels of radiofrequency radiation, either as a result of their occupational activity or as frequent users of radiofrequency emitting tools. In this paper the cytogenetic biomonitoring studies of RF-exposed humans are reviewed. A majority of these studies do show that RF-exposed individuals have increased frequencies of genetic damage (e.g., chromosomal aberrations) in their lymphocytes or exfoliated buccal cells. However, most of the studies, if not all, have a number of shortcomings that actually prevents any firm conclusion. Radiation dosimetry was lacking in all papers, but some of the investigations were flawed by much more severe imperfections. Large well-coordinated multidisciplinary investigations are needed in order to reach any robust conclusion.

  19. Mammalian cells exposed to ionizing radiation: Structural and biochemical aspects.

    PubMed

    Sabanero, Myrna; Azorín-Vega, Juan Carlos; Flores-Villavicencio, Lérida Liss; Castruita-Dominguez, J Pedro; Vallejo, Miguel Angel; Barbosa-Sabanero, Gloria; Cordova-Fraga, Teodoro; Sosa-Aquino, Modesto

    2016-02-01

    Acute or chronic exposure to ionizing radiation is a factor that may be hazardous to health. It has been reported that exposure to low doses of radiation (less than 50 mSv/year) and subsequently exposure to high doses produces greater effects in people. It has been reported that people who have been exposed to low doses of radiation (less than 50 mSv/year) and subsequently are exposed to high doses, have greater effects. However, at a molecular and biochemical level, it is an unknown alteration. This study, analyzes the susceptibility of a biological system (HeLa ATCC CCL-2 human cervix cancer cell line) to ionizing radiation (6 and 60 mSv/90 s). Our research considers multiple variables such as: total protein profile, mitochondrial metabolic activity (XTT assay), cell viability (Trypan blue exclusion assay), cytoskeleton (actin microfilaments), nuclei (DAPI), and genomic DNA. The results indicate, that cells exposed to ionizing radiation show structural alterations in nuclear phenotype and aneuploidy, further disruption in the tight junctions and consequently on the distribution of actin microfilaments. Similar alterations were observed in cells treated with a genotoxic agent (200 μM H2O2/1h). In conclusion, this multi-criteria assessment enables precise comparisons of the effects of radiation between various line cells. However, it is necessary to determine stress markers for integration of the effects of ionizing radiation.

  20. Expose : procedure and results of the joint experiment verification tests

    NASA Astrophysics Data System (ADS)

    Panitz, C.; Rettberg, P.; Horneck, G.; Rabbow, E.; Baglioni, P.

    The International Space Station will carry the EXPOSE facility accommodated at the universal workplace URM-D located outside the Russian Service Module. The launch will be affected in 2005 and it is planned to stay in space for 1.5 years. The tray like structure will accomodate 2 chemical and 6 biological PI-experiments or experiment systems of the ROSE (Response of Organisms to Space Environment) consortium. EXPOSE will support long-term in situ studies of microbes in artificial meteorites, as well as of microbial communities from special ecological niches, such as endolithic and evaporitic ecosystems. The either vented or sealed experiment pockets will be covered by an optical filter system to control intensity and spectral range of solar UV irradiation. Control of sun exposure will be achieved by the use of individual shutters. To test the compatibility of the different biological systems and their adaptation to the opportunities and constraints of space conditions a profound ground support program has been developed. The procedure and first results of this joint Experiment Verification Tests (EVT) will be presented. The results will be essential for the success of the EXPOSE mission and have been done in parallel with the development and construction of the final hardware design of the facility. The results of the mission will contribute to the understanding of the organic chemistry processes in space, the biological adaptation strategies to extreme conditions, e.g. on early Earth and Mars, and the distribution of life beyond its planet of origin.

  1. Definitive Surgical Treatment of Infected or Exposed Ventral Hernia Mesh

    PubMed Central

    Szczerba, Steven R.; Dumanian, Gregory A.

    2003-01-01

    Objective To discuss the difficulties in dealing with infected or exposed ventral hernia mesh, and to illustrate one solution using an autogenous abdominal wall reconstruction technique. Summary Background Data The definitive treatment for any infected prosthetic material in the body is removal and substitution. When ventral hernia mesh becomes exposed or infected, its removal requires a solution to prevent a subsequent hernia or evisceration. Methods Eleven patients with ventral hernia mesh that was exposed, nonincorporated, with chronic drainage, or associated with a spontaneous enterocutaneous fistula were referred by their initial surgeons after failed local wound care for definitive management. The patients were treated with radical en bloc excision of mesh and scarred fascia followed by immediate abdominal wall reconstruction using bilateral sliding rectus abdominis myofascial advancement flaps. Results Four of the 11 patients treated for infected mesh additionally required a bowel resection. Transverse defect size ranged from 8 to 18 cm (average 13 cm). Average procedure duration was 3 hours without bowel repair and 5 hours with bowel repair. Postoperative length of stay was 5 to 7 days without bowel repair and 7 to 9 days with bowel repair. Complications included hernia recurrence in one case and stitch abscesses in two cases. Follow-up ranges from 6 to 54 months (average 24 months). Conclusions Removal of infected mesh and autogenous flap reconstruction is a safe, reliable, and one-step surgical solution to the problem of infected abdominal wall mesh. PMID:12616130

  2. Altered amygdala connectivity in urban youth exposed to trauma

    PubMed Central

    Marusak, Hilary A.; Tocco, Maria A.; Vila, Angela M.; McGarragle, Olivia; Rosenberg, David R.

    2015-01-01

    Early life trauma exposure represents a potent risk factor for the development of mental illnesses such as anxiety, depression and post-traumatic stress disorder. Moreover, deleterious consequences of trauma are exacerbated in youth living in impoverished, urban environments. A priori probability maps were used to examine resting-state functional connectivity (FC) of the amygdala in 21 trauma-exposed, and 21 age- and sex-matched urban children and adolescents (youth) without histories of trauma. Intrinsic FC analyses focused on amygdala-medial prefrontal circuitry, a key emotion regulatory pathway in the brain. We discovered reduced negative amygdala-subgenual cingulate connectivity in trauma-exposed youth. Differences between groups were also identified in anterior insula and dorsal anterior cingulate to amygdala connectivity. Overall, results suggest a model in which urban-dwelling trauma-exposed youth lack negative prefrontal to amygdala connectivity that may be critical for regulation of emotional responses. Functional changes in amygdala circuitry might reflect the biological embedding of stress reactivity in early life and mediate enhanced vulnerability to stress-related psychopathology. PMID:25836993

  3. Ethanol emission from loose corn silage and exposed silage particles

    NASA Astrophysics Data System (ADS)

    Hafner, Sasha D.; Montes, Felipe; Rotz, C. Alan; Mitloehner, Frank

    2010-11-01

    Silage on dairy farms has been identified as a major source of volatile organic compound (VOC) emissions. However, rates of VOC emission from silage are not accurately known. In this work, we measured ethanol (a dominant silage VOC) emission from loose corn silage and exposed corn silage particles using wind tunnel systems. Flux of ethanol was highest immediately after exposing loose silage samples to moving air (as high as 220 g m -2 h -1) and declined by as much as 76-fold over 12 h as ethanol was depleted from samples. Emission rate and cumulative 12 h emission increased with temperature, silage permeability, exposed surface area, and air velocity over silage samples. These responses suggest that VOC emission from silage on farms is sensitive to climate and management practices. Ethanol emission rates from loose silage were generally higher than previous estimates of total VOC emission rates from silage and mixed feed. For 15 cm deep loose samples, mean cumulative emission was as high as 170 g m -2 (80% of initial ethanol mass) after 12 h of exposure to an air velocity of 5 m s -1. Emission rates measured with an emission isolation flux chamber were lower than rates measured in a wind tunnel and in an open setting. Results show that the US EPA emission isolation flux chamber method is not appropriate for estimating VOC emission rates from silage in the field.

  4. Patterns of growth and development in narcotic-exposed children.

    PubMed

    Lifschltz, M H; Wilson, G S

    1991-01-01

    The results of the studies reviewed indicate that intrauterine growth is adversely affected by drug use during pregnancy. Whether the impairment is a direct effect of narcotic exposure or is the result of the interaction of deleterious health, environmental, and socioeconomic factors closely associated with the lifestyle of the woman who abuses drugs cannot be determined at present. Reports on the long-term effects of drug use on growth and intellectual functioning in the offspring of women who abuse drugs are not consistent. While some studies indicate that most of the exposed infants exhibit catchup growth by 6 months of age (Lifschitz et al. 1983, 1985), one methodologically strong study suggests that methadone may have a small direct teratogenic effect reflected in reduced head size at 2 years of age (Hans 1989). Unexplained is the pattern of growth deceleration observed in some narcotic-exposed children (Lifschitz et al. 1983, 1985). The few available reports on long-term outcome concur that narcotic-exposed children have a high incidence of behavioral and learning problems (Strauss et al. 1979; Rosen and Johnson 1985; Wilson 1989), but population studies have been too small to demonstrate that they differ significantly from controls. There is a suggestion that narcotic use during pregnancy promotes a biological vulnerability to adverse environments, manifested in the neurobehavioral and intellectual areas.

  5. Unmet Health Care Needs among Children Exposed to Parental Incarceration.

    PubMed

    Turney, Kristin

    2017-01-20

    Objectives The incarceration rate in the United States has increased rapidly since the mid-1970s and, accordingly, a large number of children are exposed to parental incarceration. Research finds that parental incarceration is associated with deleterious physical and mental health outcomes among children, but little is known about these children's health care access. Methods I used data from the 2011-2012 National Survey of Children's Health (N = 95,531), a population-based and nationally representative survey of non-institutionalized children ages 0-17 in the United States, to estimate the association between exposure to parental incarceration and children's unmet health care needs. Results In logistic regression models that adjust for an array of demographic and socioeconomic characteristics, children exposed to parental incarceration, compared to their counterparts, have 1.26 (95% CI 1.02-1.54) times the odds of having any unmet health care need. Analyses that disaggregate by type of unmet health care need (mental, dental, vision, mental health, or other) suggest this association is driven by a greater likelihood of unmet mental health care needs (OR 1.60; 95% CI 1.04-2.46). Conclusions Children exposed to parental incarceration, a vulnerable group especially at risk of physical and mental health problems, face challenges to health care access, especially mental health care access. Given that parental incarceration is concentrated among those children most in need of health care, parental incarceration may exacerbate existing inequalities in unmet health care needs.

  6. Bleomycin sensitivity test in the exposed and reference human populations.

    PubMed

    Michalska, J; Motykiewicz, G; Kalinowska, E; Chorazy, M

    1998-09-25

    Sensitivity to bleomycin was investigated in lymphocytes collected from three groups of males: 30 occupationally exposed cokery workers, 38 environmentally exposed Silesian citizen and 35 rural inhabitants. The data were analyzed at both the individual and group levels. The first analysis has revealed a substantial interindividual variability in the level of generated breaks (breaks per cell, b/c). This variability was independent of the age of the donor, smoking habit and X-ray exposure as tested in the multiple regression model. The means per group for the occupationally and environmentally exposed persons were almost the same with the values of 0.674 and 0.639, respectively. These two groups differed significantly from the rural population (b/c=0.448, p<0.001 by MANOVA). The reproducibility of the assay was satisfying (p>0.49 by the Wilcoxon matched paired test) after omitting 7 out of 49 repeatedly sampled donors. Those persons exhibited extremely high b/c rates in the first sampling.

  7. Increased gluconeogenesis in rats exposed to hyper-G stress

    NASA Technical Reports Server (NTRS)

    Daligcon, B. C.; Oyama, J.; Hannak, K.

    1985-01-01

    The effect of glucogenesis on the plasma glucose and liver glycogen of rats exposed to hyper-G stress is investigated. Twelve male Sprague-Dawley rats are injected with C-14 lactate, alanine, of glycerol, and six of the rats are exposed to 3.1 G for 0.25, 0.50, and 1.0 hr. The plasma glucose and liver glycogen of the centrifuged and noncentrifuged rats are analyzed. A significant increase in the C-14 incorporation of the substrate into the plasma glucose and liver glycogen is observed in the centrifuged rats. The injection of 5-methoxyindole-2-carboxylic acid, a gluconeogenesis inhibitor, results in a blocked increase in plasma glucose and liver glycogen. The role of epinephrine on the hyperglycemic and liver glycogen responses of centrifuged rats is studied. It is concluded that the initial increase in plasma glucose and liver glycogen in rats exposed to hyper-G stress is the result of an increased rate of gluconeogenesis.

  8. Expose-R experiment on effects of open space condition on survivorship in dormant stages of aquatic invertebrates

    NASA Astrophysics Data System (ADS)

    Alekseev, Victor; Novikova, Nataliya; Levinskikh, Margarita; Sychev, Vladimir; Yusoff, Fatimah; Azuraidi, Osman

    2012-07-01

    Dormancy protects animals and plants in harsh environmental conditions from months up to hundred years. This phenomenon is perspective for space researches especially for interplanetary missions. Direct experiments in open space BYORYSK supported in principle the fact of survivorship of bacteria, fungi spores, seed of plants and crustacean dormant cysts. Even though the rate of survivorship in long-term treatments was low but good enough to conclude that biological invasion even to Mars is a real danger. As soon as the BYORYSK lunch was made of metal the possibility for resting stages to survive under UV treatment in vacuum without some protection was not clear. To test it an ESA and RSA equipment titled EXPOSE-R was applied. The EXPOSE-R facility was an external facility attached to the outside of the Zvezda Service Module in ISS in the end of November 2008. It had glace windows transparent for UV-radiation and possibility to measure temperature, space- and UV-radiation. Among a number of experiments requiring exposure to the open space environment it had a biological launch containing resting stages of terrestrial and aquatic organisms. These stages included dried ephippia of cladoceran Daphnia magna differentiated on size, dormant eggs of ostracode Eucypris ornate, cysts of fair-shrimp Streptocephalus torvicornis ( all from hemi desert Caspian area) and Artemis salina from salt lake Crimean populations. All dormant stages were kept in transparent to UV plastic bags placed in three layers. After about two years of exposing in open space dormant stages of 3 species A. salina, D. magna, S. torvicornis successfully survived at different scales but in second and third layers only . The highest level of survivorship was found in A. salina cysts. In preliminary land experiments that imitated land EXPOSE imitation of outside space station UV and vacuum conditions survivorship in resting eggs of D .magna, S. torvicornis and E. ornate was tested also. The total UV dose of

  9. Potassium ion fluxes in corneal epithelial cells exposed to UVB

    PubMed Central

    Ubels, John L.; Van Dyken, Rachel E.; Louters, Julienne R.; Schotanus, Mark P.; Haarsma, Loren D.

    2011-01-01

    The goal of this study was to investigate the efflux of K+ from human corneal limbal epithelial cells (HCLE) exposed to ambient levels of UVB, which is known to cause apoptosis, and to examine the effect of K+ channel blockers on loss of potassium induced by UVB. HCLE cells were exposed to 100–200 mJ/cm2 UVB, followed by incubation in culture media with 5.5 – 100 mM K+, BDS-1, Ba2+ or ouabain. To measure intracellular cations, cells were washed in 280 mM sucrose and lysed in DI water. K+ and Na+ levels in lysates were measured by ion chromatography. HCLE cells showed maximal loss of [K+]i 10 minutes after exposure to UVB and 5.5 mM K+ media, with recovery of normal K+ levels after 90 minutes. Treatment with 1 µM BDS-1 following UVB exposure reduced the loss of [K+]i retained by HCLE cells. Exposure to 0.1–5 mM Ba2+ inhibited UVB-induced K+ loss in a time and dose dependent manner. These results confirm that blocking K+ channels in HCLE cells exposed to UVB prevents efflux of K+, confirming that UVB activates K+ channels in these cells. Electrophysiology data shows that K+ channels remain highly active at least 90 minutes after UVB exposure. HCLE cells exposed to UVB and incubated 0.01–1µM ouabain did not recover from UVB-induced K+ loss. These data suggest that the Na/K pump may act to restore [K+]i to control levels in HCLE cells following UVB exposure and that the pump is not damaged by exposure to UVB. Incubation of HCLE cells exposed to UVB in medium with 25–100mM K+ media prevented K+ efflux at extracellular concentrations as low as 25mM (the concentration in tear fluid), maintaining control levels of [K+]i. In all experiments inward fluxes and intracelluar Na+ levels mirrored K+ changes, albeit at the expected lower concentrations. The prevention of UVB-induced K+i loss by 25 mM K+o is consistent with the possible contribution of the relatively high K+ concentration in tears to protection of the corneal epithelium from ambient UVB. PMID:21377460

  10. Neurologic function among termiticide applicators exposed to chlorpyrifos.

    PubMed Central

    Steenland, K; Dick, R B; Howell, R J; Chrislip, D W; Hines, C J; Reid, T M; Lehman, E; Laber, P; Krieg, E F; Knott, C

    2000-01-01

    Chlorpyrifos is a moderately toxic organophosphate pesticide. Houses and lawns in the United States receive a total of approximately 20 million annual chlorpyrifos treatments, and 82% of U.S. adults have detectable levels of a chlorpyrifos metabolite (3,5, 6-trichloro-2-pyridinol; TCP) in the urine. The U.S. Environmental Protection Agency has estimated that there are 5,000 yearly reported cases of accidental chlorpyrifos poisoning, and approximately one-fourth of these cases exhibit symptoms. Organophosphates affect the nervous system, but there are few epidemiologic data on chlorpyrifos neurotoxicity. We studied neurologic function in 191 current and former termiticide applicators who had an average of 2.4 years applying chlorpyrifos and 2.5 years applying other pesticides, and we compared them to 189 nonexposed controls. The average urinary TCP level for 65 recently exposed applicators was 629.5 microg/L, as compared to 4.5 microg/L for the general U.S. population. The exposed group did not differ significantly from the nonexposed group for any test in the clinical examination. Few significant differences were found in nerve conduction velocity, arm/hand tremor, vibrotactile sensitivity, vision, smell, visual/motor skills, or neurobehavioral skills. The exposed group did not perform as well as the nonexposed group in pegboard turning tests and some postural sway tests. The exposed subjects also reported significantly more symptoms, including memory problems, emotional states, fatigue, and loss of muscle strength; our more quantitative tests may not have been adequate to detect these symptoms. Eight men who reported past chlorpyrifos poisoning had a pattern of low performance on a number of tests, which is consistent with prior reports of chronic effects of organophosphate poisoning. Overall, the lack of exposure effects on the clinical examination was reassuring. The findings for self-reported symptoms raise some concern, as does the finding of low performance

  11. Exposed Ice in the Northern Mid-Latitudes of Mars

    NASA Astrophysics Data System (ADS)

    Allen, C. C.

    2007-12-01

    Ice-Rich Layer: Polygonal features with dimensions of approximately 100 meters, bounded by cracks, are commonly observed on the martian northern plains. These features are generally attributed to thermal cracking of ice-rich sediments, in direct analogy to polygons in terrestrial polar regions [1,2]. We mapped polygons in the northern mid-latitudes (30 to 65 N) using MOC and HiRISE images [3]. Polygons are scattered across the northern plains, with a particular concentration in western Utopia Planitia. This region largely overlaps the Late Amazonian Astapus Colles unit, characterized by polygonal terrain and nested pits consistent with periglacial and thermokarst origins [4]. Bright and Dark Polygonal Cracks: An examination of all MOC images (1997 through 2003) covering the study area demonstrated that, at latitudes of 55 to 65 N, most of the imaged polygons show bright bounding cracks. We interpret these bright cracks as exposed ice. Between 40 and 55 N, most of the imaged polygons show dark bounding cracks [5]. These are interpreted as polygons from which the exposed ice has been removed by sublimation. The long-term stability limit for exposed ice, even in deep cracks, apparently lies near 55 N. Bright and Dark Spots: Many HiRISE and MOC frames showing polygons in the northern plains also show small numbers of bright and dark spots, particularly in western Utopia Planitia. Many of the spots are closely associated with collapse features suggestive of thermokarst. The spots range from tens to approximately 100 meters in diameter. The bright spots are interpreted as exposed ice, due to their prevalence on terrain mapped as ice rich. The dark spots are interpreted as former bright spots, which have darkened as the exposed ice is lost by sublimation. The bright spots may be the martian equivalents of pingos, ice-cored mounds found in periglacial regions on Earth [6,7,8,9, 10]. Terrestrial pingos from which the ice core has melted often collapse to form depressions

  12. Juvenile hypothyroidism among two populations exposed to radioiodine.

    PubMed Central

    Goldsmith, J R; Grossman, C M; Morton, W E; Nussbaum, R H; Kordysh, E A; Quastel, M R; Sobel, R B; Nussbaum, F D

    1999-01-01

    We found an epidemic of juvenile hypothyroidism among a population of self-defined "downwinders" living near the Hanford nuclear facility located in southeast Washington State. The episode followed massive releases of 131I. Self-reported data on 60 cases of juvenile hypothyroidism (<20 years of age) among a group of 801 Hanford downwinders are presented, as well as data concerning the thyroid status of approximately 160,000 children exposed to radioiodine before 10 years of age as a result of the 26 April 1986 Chernobyl explosion in the former Soviet Union. These children were residents of five regions near Chernobyl. They were examined by standardized screening protocols over a period of 5 years from 1991 to 1996. They are a well-defined group of 10 samples. Fifty-six cases of hypothyroidism were found among boys and 92 among girls. Body burdens of 137Cs have been correlated with hypothyroidism prevalence rates. On the other hand, the group of juvenile (<20 years of age) Hanford downwinders is not a representative sample. Most of the 77 cases of juvenile hypothyroidism in the Hanford group were diagnosed from 1945 to 1970. However, the ratio of reported cases to the county population under 20 years of age is roughly correlated with officially estimated mean levels of cumulative thyroid 131I uptake in these counties, providing evidence that juvenile hypothyroidism was associated with radioiodine exposures. Because even subtle hypothyroidism may be of clinical significance in childhood and can be treated, it may be useful to screen for the condition in populations exposed to radioiodine fallout. Although radiation exposure is associated with hypothyroidism, its excess among fallout-exposed children has not been previously quantified. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:10090710

  13. Hepatitis A in workers exposed to sewage: a systematic review

    PubMed Central

    Glas, C; Hotz, P; Steffen, R

    2001-01-01

    OBJECTIVES—To assess whether the scientific literature supports the hypothesis that workers exposed to sewage are at higher risk of hepatitis A (HA).
METHODS—All original papers reporting epidemiological studies published in English, French, or German which reported on the risk of HA infection in workers exposed to sewage were eligible. They were identified by several methods and each original paper was assessed independently with a checklist by two people. Studies were classified according to the strength of their design. Non-eligible studies were also examined to assess the impact of publication bias. If the risk estimates diverged widely, causes for heterogeneity were assessed. A distinction was made between seroprevalence studies based on subclinical HA (defined only by the presence of anti-HA antibodies) and clinical HA.
RESULTS—17 eligible studies were identified. No indication of an increased risk of clinical HA could be found. For seroprevalence the studies with the strongest design suggested a slightly increased risk of subclinical HA with an odds ratio (OR) <2.5. Heterogeneity was considerable and precluded a meta-analysis. Considering non-eligible studies would still decrease the OR.
CONCLUSIONS—The systematic review does not confirm an increased risk of clinical HA in workers exposed to sewage. An increased risk of subclinical HA cannot be excluded but the association between seropositivity and exposure to sewage was not strong and became still weaker if publication bias was taken into account.


Keywords: hepatitis A; sewage; systematic review PMID:11706141

  14. Petroleum films exposed to sunlight produce hydroxyl radical.

    PubMed

    Ray, Phoebe Z; Tarr, Matthew A

    2014-05-01

    Sunlight exposed oil films on seawater or pure water produced substantial amounts of hydroxyl radical as a result of irradiation. Oil was collected from the surface of the Gulf of Mexico following the Deepwater Horizon spill and exposed to simulated sunlight in thin films over water. Photochemical production of hydroxyl radical was measured with benzoic acid as a selective chemical probe in the aqueous layer. Total hydroxyl radical formation was studied using high benzoic acid concentrations and varying exposure time. The total amount of hydroxyl radical produced in 24 h irradiations of thin oil films over Gulf of Mexico water and pure water were 3.7×10(-7) and 4.2×10(-7) moles respectively. Steady state concentrations of hydroxyl radical were measured using a competition kinetics approach. Hydroxyl radical concentrations of 1.2×10(-16) to 2.4×10(-16) M were observed for seawater and pure water under oil films. Titanium dioxide (TiO2) nanomaterials were added to the system in an effort to determine if the photocatalyst would enhance oil photodegradation. The addition of TiO2 nanoparticles dramatically changed the observed formation rate of hydroxyl radical in the systems with NP water at pH 3, showing increased formation rate in many cases. With photocatalyst, the steady state concentration of radical decreased, predominantly due to an increase in the hydroxyl radical scavenging rate with oxide present. This study illustrates that oil is a strong and important source of hydroxyl radical when exposed to sunlight. The fate of oil and other dissolved species following oil spills will be heavily dependent on the formation and fate of hydroxyl radical.

  15. Study of electronic transport in gamma ray exposed nanowires

    SciTech Connect

    Gehlawat, Devender Chauhan, R.P.

    2014-01-01

    Graphical abstract: A sharp decline in the I–V characteristics of Cu (and Cd) nanowires was experimentally observed after the gamma ray exposure of nanowires. Irradiation induced transformations in the granular properties and the resonance state of electron–phonon coupling beyond a particular value of external field may be accountable for observed shape of I–V characteristics in gamma ray exposed nanowires. - Highlights: • Cu and Cd nanowires were synthesized by technique of electrodeposition in templates. • The nanowires were exposed to different doses of gamma ray photons. • A sharp decline in the current in I–V characteristics (IVC) was observed. • Structural deviation in terms of granular orientations was also analysed. • The electron–phonon coupling may be responsible for observed sharp decline in IVC. - Abstract: One dimensional nanostructures provide the most restricted and narrow channel for the transport of charge carriers and therefore 1D structures preserve their significance from the viewpoint of electronic devices. The net radiation effect on nanomaterials is expected to be more (due to their increased reactivity and lesser bulk volume) than their bulk counterparts. Radiation often modifies the structure and simultaneously the other physical properties of materials. In this manner, the irradiation phenomenon could be counted as a strong criterion to induce changes in the structural and electrical properties of nanowires. We have studied the effect of gamma rays on the electronic flow through Cu and Cd nanowires by plotting their I–V characteristics (IVC). The IVC of gamma ray exposed nanowires was found to be a combination of the linear and nonlinear regions and a decreasing pattern in the electrical conductivity (calculated from the linear portion of IVC) was observed as we increased the dose of gamma rays.

  16. Cultural Heritage exposed to landslide and flood risk in Italy

    NASA Astrophysics Data System (ADS)

    Spizzichino, Daniele; Cacace, Carlo; Iadanza, Carla; Trigila, Alessandro

    2013-04-01

    Italy is the country that owns most of the world cultural heritage as it's clear from the list of sites of inestimable value to humanity, prepared by UNESCO under the Convention concerning the protection of the world cultural and natural heritage ratified in 1972. The Italian territory is also particularly prone to natural hazards such as landslides, floods, earthquakes, volcanic eruptions, subsidence and coastal erosion which undermine the protection and preservation of cultural heritage. Aim of the present work is to provide an estimate of architectural, monumental and archaeological heritage exposed to landslide and flood risk at national scale. The input data are: the Italian Cultural Heritage database (Carta del Rischio del patrimonio culturale) realized by ISCR (Central Institute for the Conservation and Restoration); the Italian Landslide Inventory (Progetto IFFI) developed by ISPRA (Italian National Institute for Environmental Protection and Research) and the Regions and Self-Governing Provinces of Italy and the flood hazard zones defined by the Italian River Basin Authorities. Italian landslide inventory contains more than 486,000 landslides affecting an area of about 20,800 km2, equal to 6.9% of Italian territory. In order to estimate the number and type of cultural heritage at risk some GIS processing have been carried out, overlapping information from the above mentioned databases. The analysis provided the following results: Cultural Heritage exposed to landslide risk were estimated to 5.511 (6.6%) while the ones exposed to flood risk results 9.859 (11.7%). Two case studies concerning landslide phenomena affecting important Italian municipalities and the flood risk of historical centre of Rome, have been also analyzed. These results could be used to identify priorities and plan field surveys, detailed studies and monitoring systems, allowing job scheduling of cultural heritage maintenance. This need becomes more and more a necessity taking into account

  17. Genetic damage in wood dust-exposed workers.

    PubMed

    Rekhadevi, P V; Mahboob, M; Rahman, M F; Grover, Paramjit

    2009-01-01

    Exposure to wood dust is common in carpentry workshops. Wood dust is known to be a human carcinogen, with a very high relative risk of adenocarcinoma of the nasal cavities and paranasal sinuses. The goal of this investigation was to conduct genotoxicity monitoring of carpenters involved in wooden furniture industry in order to test possible wood dust-induced genotoxic effects due to occupational exposure. The level of genetic damage was determined by comet, micronucleus and chromosomal aberration (CA) assays in peripheral blood lymphocytes (PBL) of 60 carpentry workers. In addition, the micronucleus test in buccal epithelial cells was carried out in the same subjects. Total antioxidant enzyme activities were measured by the indices: superoxide dismutase, glutathione peroxidase and catalase. A group of 60 non-exposed subjects matched by age, smoking and alcohol consumption habits were chosen as controls. The effect of age, smoking, alcohol consumption and duration of exposure was also analysed in the subjects of the present study. The results showed a statistically significant increase in mean DNA damage by comet assay, micronuclei frequency in buccal cells as well as PBL and frequency of CA in the exposed workers when compared to controls (P < 0.05). Analysis of the data showed that all the confounding factors had a significant effect on DNA damage and micronucleus frequency in buccal epithelial cells and PBL. Smoking and alcohol consumption did not have any significant effect by chromosomal aberration test. Antioxidant enzyme levels significantly decreased in the exposed subjects. Our findings indicate enhanced levels of genotoxicity in carpenters. Hence, these workers may have an increased cancer risk.

  18. Exposed-core chalcogenide microstructured optical fibers for chemical sensing

    NASA Astrophysics Data System (ADS)

    Troles, Johann; Toupin, Perrine; Brilland, Laurent; Boussard-Plédel, Catherine; Bureau, Bruno; Cui, Shuo; Mechin, David; Adam, Jean-Luc

    2013-05-01

    Chemical bonds of most of the molecules vibrate at a frequency corresponding to the near or mid infrared field. It is thus of a great interest to develop sensitive and portable devices for the detection of specific chemicals and biomolecules for various applications in health, the environment, national security and so on. Optical fibers define practical sensing tools. Chalcogenide glasses are known for their transparency in the infrared optical range and their ability to be drawn as fibers. They are consequently good candidates to be used in biological/chemical sensing. For that matter, in the past decade, chalcogenide glass fibers have been successfully implemented in evanescent wave spectroscopy experiments, for the detection of bio-chemical species in various fields of applications including microbiology and medicine, water pollution and CO2 detection. Different types of fiber can be used: single index fibers or microstructured fibers. Besides, in recent years a new configuration of microstructured fibers has been developed: microstructured exposed-core fibers. This design consists of an optical fiber with a suspended micron-scale core that is partially exposed to the external environment. This configuration has been chosen to elaborate, using the molding method, a chalcogenide fiber for chemical species detection. The sensitivity of this fiber to detect molecules such as propan-2-ol and acetone has been compared with those of single index fibers. Although evanescent wave absorption is inversely proportional to the fiber diameter, the result shows that an exposed-core fiber is much more sensitive than a single index fiber having a twice smaller external diameter.

  19. Scanning Tunneling Microscopy analysis of space-exposed polymer films

    NASA Technical Reports Server (NTRS)

    Kalil, Carol R.; Young, Philip R.

    1993-01-01

    The characterization of the surface of selected space-exposed polymer films by Scanning Tunneling Microscopy (STM) is reported. Principles of STM, an emerging new technique for materials analysis, are reviewed. The analysis of several films which received up to 5.8 years of low Earth orbital (LEO) exposure onboard the NASA Long Duration Exposure Facility (LDEF) is discussed. Specimens included FEP Teflon thermal blanket material, Kapton film, and several experimental polymer films. Ultraviolet and atomic oxygen-induced crazing and erosion are described. The intent of this paper is to demonstrate how STM is enhancing the understanding of LEO space environmental effects on polymer films.

  20. [Hematologic changes in patients chronically exposed to benzene].

    PubMed

    Ruiz, M A; Vassallo, J; de Souza, C A

    1993-04-01

    A study was carried out into the hematological abnormalities of peripheral blood bone marrow in patients chronically exposed to benzene. The metabolic biotransformation and the mechanisms involved in toxicity are described. Hematological data are described and discussed. Macrocytosis and lymphopenia are the earliest hematological signs of benzene toxicity. Bone marrow abnormalities are demonstrated by the complementary methods of cytology and histology. Global hypocellularity was mainly due to the granulocytic series. Mastocytosis, eosinophilia and magakariocytic abnormalities are also presented. Inflammatory abnormalities and signs of dismyelopoiese could also be observed. The importance of peripheral blood abnormalities and the need for a critical approach to this important public health problem are emphasized.

  1. MOEs for Drug Interdiction: Simple Tests Expose Critical Flaws

    DTIC Science & Technology

    1991-09-01

    DTIC gN In MOEs for Drug Interdiction: Simple Tests Expose Critical Flaws Michael R. Anderberg 92-15393 92 6 1 2 0 5 3 U CENTER FOR NAVAL ANALYSES ...ORGANIZATION REPORT NUMBER Center for Naval Analyses CRM 91-48 4401 Ford Avenue Alexandria, Virginia 22302-0268 9. SPONSORING/MONITORING AGENCY NAME(S) AND...S%& 2MS.18 ECENTER FOR NAVAL ANALYSES 4401 Ford Avenue • Post Office Box 16268 • Alexandria, Virginia 22302-0268 * (703) 824-2000 10 October 1991

  2. Final results of space exposed experiment developed for students

    NASA Technical Reports Server (NTRS)

    Grigsby, Doris K.

    1993-01-01

    SEEDS was a cooperative endeavor of NASA Headquarters, the NASA Langley Research Center, and the George W. Park Seed Company. Approximately 132,000 SEEDS kits containing Rutger's tomato seeds that had flown on LDEF, as well as similar seeds that had been stored in a climate-controlled warehouse for the same time period, were sent to schools in every state and 30 foreign countries. Student researchers from kindergarten through university compared germination and growth characteristics of the space-exposed and Earth-based seeds and returned data to NASA for analysis. Important scientific information was gained as students reported very little difference between the two seed groups.

  3. Charge fluctuations for particles on a surface exposed to plasma

    SciTech Connect

    Sheridan, T. E.; Hayes, A.

    2011-02-28

    We develop a stochastic model for the charge fluctuations on a microscopic dust particle resting on a surface exposed to plasma. We find in steady state that the fluctuations are normally distributed with a standard deviation that is proportional to (CT{sub e}){sup 1/2}, where C is the particle-surface capacitance and T{sub e} is the plasma electron temperature. The time for an initially uncharged ensemble of particles to reach the steady state distribution is directly proportional to CT{sub e}.

  4. Erosion of graphite surface exposed to hot supersonic hydrogen gas

    NASA Technical Reports Server (NTRS)

    Sharma, O. P.

    1972-01-01

    A theoretical model based on laminar boundary layer flow equations is developed to predict the erosion rate of a graphite (AGCarb-101) surface exposed to a hot supersonic stream of hydrogen gas. The supersonic flow in the nozzle outside the boundary layer formed over the surface of the specimen is determined by assuming one-dimensional isentropic conditions. An overall surface reaction rate expression based on the experimental studies by Clarke and Fox is used to describe the interaction of hydrogen with graphite. A satisfactory agreement is found between the results of the computation, and the available experimental data. Some shortcomings of the model, and further possible improvements are discussed.

  5. Susuk - black magic exposed "white" by dental radiographs.

    PubMed

    F, Arishiya Thapasum; Mohammed, Faraz

    2014-07-01

    Susuk or charm needles are a facial cum body art widely practiced among women of Malaysia, Brunei, Singapore, Thailand and Indonesia. These are small, needle-shaped metallic talismans inserted subcutaneously in different parts of the body. The concealed art of susuk was "exposed" by routine radiographic examination in the oral and maxillofacial region. This paper reports two such cases of unusual incidental radiographic finding in dental radiographs which were taken on a routine basis as part of the diagnostic work up. This article will also primarily enlighten the importance of radiographs in detecting such charm needles as the wearer keeps the body art a "hidden secret" thereby avoiding misdiagnosis.

  6. Relative Efficiency Of TLD-100 Exposed to X-Rays

    SciTech Connect

    Ixquiac-Cabrera, J. M.; Gamboa-de Buen, I.; Avila, O.; Brandan, M. E.

    2008-08-11

    The relative efficiency of TLD-100 (LiF:Mg,Ti) exposed to X-rays in the range from 30 to 250 kV, with respect to {sup 60}CO gamma rays has been measured. Glow curves were deconvoluted into peaks 3 to 9. All efficiencies were greater than 1 having a maximum of 1.38 for the dosimetric region (peaks 3+4+5) and peaks 4, 5 and 9, and 2.2 for peaks 6a, 6b, 7 and 8 at the effective energy of 24 keV.

  7. Maximally exposed offsite individual location determination for NESHAPS compliance

    SciTech Connect

    Simpkins, A.A.

    2000-03-13

    The Environmental Protection Agency (EPA) requires the use of the computer program CAP88 for demonstrating compliance with the National Emission Standard for Hazardous Air Pollutants (NESHAPS.) One of the inputs required for CAP88 is the location of the maximally exposed individual (MEI) by sector and distance. Distances to the MEI have been determined for 15 different potential release locations at SRS. These locations were compared with previous work and differences were analyzed. Additionally, SREL Conference Center was included as a potential offsite location since in the future it may be used as a dormitory. Worst sectors were then determined based on the distances.

  8. Assimilation of 3H in photosynthesizing leaves exposed to HTO.

    PubMed

    Guenot, J; Belot, Y

    1984-12-01

    Potato and wine grape plants were exposed for a period of 4 h to tritiated water vapor, and simultaneously to 14CO2 which served as a tracer for photosynthetic assimilation. During and after exposure, foliar samples were collected in which the exchangeable and nonexchangeable fractions of organic 3H were determined, taking care that the exchangeable fraction should not be lost to atmosphere. It was demonstrated that about 20% of the organic H in vegetation could be exchanged with 3H of tissue water, and that nonexchangeable 3H was fixed by photosynthesis. The kinetic behavior of the 2 forms was very different.

  9. Exposed water ice discovered near the south pole of Mars

    USGS Publications Warehouse

    Titus, T.N.; Kieffer, H.H.; Christensen, P.R.

    2003-01-01

    The Mars Odyssey Thermal Emission Imaging System (THEMIS) has discovered water ice exposed near the edge of Mars' southern perennial polar cap. The surface H2O ice was first observed by THEMIS as a region that was cooler than expected for dry soil at that latitude during the summer season. Diurnal and seasonal temperature trends derived from Mars Global Surveyor Thermal Emission Spectrometer observations indicate that there is H2O ice at the surface. Viking observations, and the few other relevant THEMIS observations, indicate that surface H2O ice may be widespread around and under the perennial CO2 cap.

  10. Exposed water ice discovered near the south pole of Mars.

    PubMed

    Titus, Timothy N; Kieffer, Hugh H; Christensen, Phillip R

    2003-02-14

    The Mars Odyssey Thermal Emission Imaging System (THEMIS) has discovered water ice exposed near the edge of Mars' southern perennial polar cap. The surface H2O ice was first observed by THEMIS as a region that was cooler than expected for dry soil at that latitude during the summer season. Diurnal and seasonal temperature trends derived from Mars Global Surveyor Thermal Emission Spectrometer observations indicate that there is H2O ice at the surface. Viking observations, and the few other relevant THEMIS observations, indicate that surface H2O ice may be widespread around and under the perennial CO2 cap.

  11. The Immune System of HIV-Exposed Uninfected Infants

    PubMed Central

    Abu-Raya, Bahaa; Kollmann, Tobias R.; Marchant, Arnaud; MacGillivray, Duncan M.

    2016-01-01

    Infants born to human immunodeficiency virus (HIV) infected women are HIV-exposed but the majority remains uninfected [i.e., HIV-exposed uninfected (HEU)]. HEU infants suffer greater morbidity and mortality from infections compared to HIV-unexposed (HU) peers. The reason(s) for these worse outcomes are uncertain, but could be related to an altered immune system state. This review comprehensively summarizes the current literature investigating the adaptive and innate immune system of HEU infants. HEU infants have altered cell-mediated immunity, including impaired T-cell maturation with documented hypo- as well as hyper-responsiveness to T-cell activation. And although prevaccination vaccine-specific antibody levels are often lower in HEU than HU, most HEU infants mount adequate humoral immune response following primary vaccination with diphtheria toxoid, haemophilus influenzae type b, whole cell pertussis, measles, hepatitis B, tetanus toxoid, and pneumococcal conjugate vaccines. However, HEU infants are often found to have lower absolute neutrophil counts as compared to HU infants. On the other hand, an increase of innate immune cytokine production and expression of co-stimulatory markers has been noted in HEU infants, but this increase appears to be restricted to the first few weeks of life. The immune system of HEU children beyond infancy remains largely unexplored. PMID:27733852

  12. Prevalence of tinnitus in workers exposed to noise and organophosphates

    PubMed Central

    Delecrode, Camila Ribas; de Freitas, Thais Domingues; Frizzo, Ana Claúdia Figueiredo; Cardoso, Ana Claúdia Vieira

    2012-01-01

    Summary Introduction: Research on the workplace has emphasized the effects of noise exposure on workers' hearing, but has not considered the effects of agrochemicals. Aim: To evaluate and correlate the hearing level and tinnitus of workers exposed simultaneously to noise and organophosphates in their workplace and to measure tinnitus distress on their quality of life. Method: A retrospective clinical study. We evaluated 82 organophosphate sprinklers from the São Paulo State Regional Superintendence who were active in the fight against dengue and who were exposed to noise and organophosphates. We performed pure tone audiometry and applied the translated THI (Tinnitus Handicap Inventory) questionnaire. Results: Of the sample, 28.05% reported current tinnitus or had presented tinnitus, and the workers with tinnitus had an increased incidence of abnormal audiometry. The average hearing threshold for the 4–8-kHz frequency range of the workers with current tinnitus was higher than that of the others, and was most affected at the 4-kHz frequency. The THI score ranged 0–84, with an average score of 13.1. Twelve (52.17%) workers had THI scores consistent with discrete handicap. Conclusion: There is an increased incidence of abnormal pure tone audiometry in workers with tinnitus, and its impact on the workers' quality of life was discrete. The correlation between average hearing threshold and tinnitus distress was weak. PMID:25991953

  13. Asbestos-exposed populations: prevention, care, and compensation

    SciTech Connect

    Richter, E.D.; Tulchinsky, T.; Goldsmith, J.R.; Yaffe, Y.

    1984-05-01

    In Israel, the prevention and care of asbestos-associated diseases with latency periods of one to four decades (asbestosis, mesothelioma, increased frequency of cancer of the lung and other sites) are not satisfactory, and new national policies are required. Such policies have three major goals: (a) elimination or reduction of exposure to asbestos dust; (b) measures to promote cessation or drastic reduction of cigarette smoking among those currently or formerly exposed; and (c) equitable compensation for the consequences of past exposures. The practical elements of a program to achieve these three goals include (a) exposure standards and control technology; (b) identification of sources, routes, and levels of exposure and groups at risk; (c) compensation and job security; (d) medical monitoring and follow-up; (e) smoking cessation; (f) selective substitution of other substances for asbestos; and (g) establishment of a panel for policy supervision and the overseeing of compensation programs. Delay in implementation risks higher death rates for asbestosis and cancer among previously exposed workers, greater exposure among current workers, loss of experienced workers from the work force, and unnecessary hardship for families not adequately compensated.

  14. Decreased glomerular filtration rate in solderers exposed to cadmium.

    PubMed Central

    Järup, L; Persson, B; Elinder, C G

    1995-01-01

    OBJECTIVES--to evaluate the degree of cadmium induced glomerular impairment and to assess the dose-response relation between cadmium dose and the prevalence of glomerular dysfunction. METHODS--A comparison of glomerular filtration rates (GFR) assessed by Cr-EDTA clearance was made in 42 solderers previously exposed to cadmium for at least five years. Blood and urine data were collected at health examinations in 1984, 1989, and 1993. Individual doses of cadmium were estimated by analysing cadmium in blood. RESULTS--Glomerular lesions induced by cadmium are irreversible and the GFR decreases with the degree of tubular damage. The GFR also decreases with cadmium dose and there is a dose-response relation between blood cadmium and prevalence of glomerular damage with 3.4% prevalence at blood cadmium concentrations below 50 nmol/l, 33% at blood cadmium concentrations between 50 and 75 nmol/l and 100% prevalence of glomerular damage when cadmium in blood exceeds 75 nmol/l. CONCLUSIONS--The kidney lesions induced by cadmium are irreversible and the prevalence of those lesions are dose dependent. There is also evidence of a dose related decrease in GFR even a long time after the end of exposure. Exposure to cadmium should therefore be minimised and workers exposed to cadmium should be examined regularly for many years after the end of exposure. PMID:8563845

  15. Evoked otoacoustic emissions in workers exposed to noise: A review

    PubMed Central

    Alcarás, Patrícia Arruda de Souza; Lüders, Débora; França, Denise Maria Vaz Romano; Klas, Regina Maria; Lacerda, Adriana Bender Moreira de; Gonçalves, Cláudia Giglio de Oliveira

    2012-01-01

    Summary Introduction: The otoacoustic emissions test is an essential tool in the evaluation of auditory function, since it allows the early detection of cochlear damage of occupational origin. Objective: To present a review of the literature and analyze the effectiveness of the clinical application of the otoacoustic emissions test in workers exposed to noise. Methods: A bibliographical search covering a period of 10 years was performed in the Virtual Health Library including published articles in national and international journals indexed in the internationally recognized databases for the health sciences, LILACS, SCIELO, and MEDLINE, using the terms “otoacoustic emissions” and “occupational exposure.” The type of published article (national/international), the type and intensity of the stimulus most commonly used for the evoked otoacoustic emissions, the gender and age of the subjects, and the conclusions from the retrospective studies were all taken into consideration. Results and Conclusions: A total of 19 articles were analyzed, 7 national and 12 international, covering subjects from 17 to 77 years of age, mostly men. The type of stimulus most commonly used for the evoked otoacoustic emissions was the distortion method (12). Through this review, we have concluded that testing of evoked otoacoustic emissions in workers exposed to noise is an important tool in the early diagnosis of noise-induced cochlear hearing disorders. PMID:25991982

  16. Radiographic abnormalities among construction workers exposed to quartz containing dust

    PubMed Central

    Tjoe, N; Burdorf, A; Parker, J; Attfield, M; van Duivenbooden, C; Heederik, D

    2003-01-01

    Background: Construction workers are exposed to quartz containing respirable dust, at levels that may cause fibrosis in the lungs. Studies so far have not established a dose-response relation for radiographic abnormalities for this occupational group. Aims: To measure the extent of radiographic abnormalities among construction workers primarily exposed to quartz containing respirable dust. Methods: A cross sectional study on radiographic abnormalities indicative of pneumoconiosis was conducted among 1339 construction workers mainly involved in grinding, (jack)-hammering, drilling, cutting, sawing, and polishing. Radiological abnormalities were determined by median results of the 1980 International Labour Organisation system of three certified "B" readers. Questionnaires were used for assessment of occupational history, presence of respiratory diseases, and symptoms and smoking habits. Results: An abnormality of ILO profusion category 1/0 and greater was observed on 10.2% of the chest radiographs, and profusion category of 1/1 or greater on 2.9% of the radiographs. The average duration of exposure of this group was 19 years and the average age was 42. The predominant type of small opacities (irregularly shaped) is presumably indicative of mixed dust pneumoconiosis. The prevalence of early signs of nodular silicosis (small rounded opacities of category 1/0 or greater) was low (0.8%). Conclusions: The study suggests an elevated risk of radiographic abnormalities among these workers with expected high exposure. An association between radiographic abnormalities and cumulative exposure to quartz containing dust from construction sites was observed, after correction for potentially confounding variables. PMID:12771392

  17. The evolution of damage in tritium exposed copper

    SciTech Connect

    Goods, S.H. )

    1991-02-01

    Severe microstructural damage has been observed in polycrystalline OFHC copper specimens thermally exposed to high pressure tritium gas at temperatures {le}200 {degree}C, but not at 300 {degree}C. No such damage occurs in single crystal specimens exposed under identical conditions, regardless of temperature. In the polycrystals, the damage takes the form of very flat, crack-like intergranular cavities. It is found that the cavitation evolves slowly with time. For short exposure times, cavities as small as 0.1 {mu}m are observed. In specimens subjected to the longest aging times, the cavities grow and link until entire grain boundary facets fail. The driving force for the growth of these cavities is attributed to the internal gas pressure of helium-3 generated by the decay of tritium. The growth kinetics of cavity microstructure are described by a coupled grain boundary, surface self-diffusion process. The tritium exposure profoundly affects the mechanical properties of the polycrystalline material, inducing a severe loss in ductility. In concert with the observed ductility loss is a change in fracture morphology from transgranular ductile rupture to intergranular fracture. Examination of the resulting grain boundary facets reveals a dimple structure. The spacing of these dimples can be correlated with the spacing of the exposure-induced grain boundary cavities.

  18. Altered immunological reactivity in HIV-1-exposed uninfected neonates.

    PubMed

    Hygino, Joana; Lima, Patrícia G; Filho, Renato G S; Silva, Agostinho A L; Saramago, Carmen S M; Andrade, Regis M; Andrade, Daniel M; Andrade, Arnaldo F B; Brindeiro, Rodrigo; Tanuri, Amilcar; Bento, Cleonice A M

    2008-06-01

    This work aimed to evaluate immune events in HIV-1-exposed uninfected neonates born from mothers who control (G1) or not (G2) the plasma viral load, using unexposed neonates as controls. Cord blood from each neonate was collected, plasma and mononuclear cells were separated and the lymphoproliferation and cytokine pattern were evaluated. The results demonstrated that the in vitro lymphoproliferation induced by polyclonal activators was higher in the G2 neonates. Nevertheless, no cell culture responded to poll synthetic HIV-1 envelope peptides. The cytokine dosage in the plasma and supernatants of polyclonally-activated cultures demonstrated that, while IL-4 and IL-10 were the dominant cytokines produced in G1 and control groups, IFN-gamma and TNF-alpha were significantly higher in G2 neonates. Systemic levels of IL-10 observed among the G1 neonates were higher in those born from anti-retroviral treated mothers. In summary, our results indicate an altered immune responsiveness in neonates exposed in utero to HIV and support the role of maternal anti-retroviral treatment to attenuate it.

  19. Longitudinal study of children exposed to sulfur oxides

    SciTech Connect

    Dodge, R.; Solomon, P.; Moyers, J.; Hayes, C.

    1985-05-01

    This study is a longitudinal comparison of the health of children exposed to markedly different concentrations of sulfur dioxide and moderately different concentrations of particulate sulfate. The four groups of subjects lived in two areas of one smelter town and in two other towns, one of which was also a smelter town. In the area of highest pollution, children were intermittently exposed to high SO/sub 2/ levels (peak three-hour average concentration exceeded 2,500 micrograms/m3) and moderate particulate SO/sub 4/= levels (average concentration was 10.1 micrograms/m3). When the children were grouped by the four gradients of pollution observed, the prevalence of cough (measured by questionnaire) correlated significantly with pollution levels (trend chi-square = 5.6, p = 0.02). No significant differences in the incidence of cough or other symptoms occurred among the groups of subjects over three years, and pulmonary function and lung function growth over the study were roughly equal among all the groups. These results suggest that intermittent elevations in SO/sub 2/ concentration, in the presence of moderate particulate SO/sub 4/= concentration, produced evidence of bronchial irritation in the subjects, but no chronic effect on lung function or lung function growth was detected.

  20. Chronic toxic encephalopathy in a painter exposed to mixed solvents.

    PubMed Central

    Feldman, R G; Ratner, M H; Ptak, T

    1999-01-01

    This paper describes symptoms and findings in a 57-year-old painter who had been exposed to various organic solvents for over 30 years. He began to work as a painter at 16 years of age, frequently working in poorly ventilated areas; he used solvents to remove paint from the skin of his arms and hands at the end of each work shift. The patient and his family noticed impaired short-term memory function and changes in affect in his early forties, which progressed until after he stopped working and was thus no longer exposed to paints and solvents. After the patient's exposures had ended, serial neuropsychological testing revealed persistent cognitive deficits without evidence of further progression, and improvement in some domains. Magnetic resonance imaging revealed global and symmetrical volume loss, involving more white than gray matter. The findings in this patient are consistent with chronic toxic encephalopathy and are differentiated from other dementing processes such as Alzheimer's disease, multi-infarct (vascular) dementia, and alcoholic dementia. Previous descriptions in the literature of persistent neurobehavioral effects associated with chronic exposure to organic solvents corroborate the findings in this case. Images Figure 2 PMID:10210698

  1. Error-related negativities during spelling judgments expose orthographic knowledge.

    PubMed

    Harris, Lindsay N; Perfetti, Charles A; Rickles, Benjamin

    2014-02-01

    In two experiments, we demonstrate that error-related negativities (ERNs) recorded during spelling decisions can expose individual differences in lexical knowledge. The first experiment found that the ERN was elicited during spelling decisions and that its magnitude was correlated with independent measures of subjects' spelling knowledge. In the second experiment, we manipulated the phonology of misspelled stimuli and observed that ERN magnitudes were larger when misspelled words altered the phonology of their correctly spelled counterparts than when they preserved it. Thus, when an error is made in a decision about spelling, the brain processes indexed by the ERN reflect both phonological and orthographic input to the decision process. In both experiments, ERN effect sizes were correlated with assessments of lexical knowledge and reading, including offline spelling ability and spelling-mediated vocabulary knowledge. These results affirm the interdependent nature of orthographic, semantic, and phonological knowledge components while showing that spelling knowledge uniquely influences the ERN during spelling decisions. Finally, the study demonstrates the value of ERNs in exposing individual differences in lexical knowledge.

  2. The Exposed Proteomes of Brachyspira hyodysenteriae and B. pilosicoli

    PubMed Central

    Casas, Vanessa; Vadillo, Santiago; San Juan, Carlos; Carrascal, Montserrat; Abian, Joaquin

    2016-01-01

    Brachyspira hyodysenteriae and Brachyspira pilosicoli are well-known intestinal pathogens in pigs. B. hyodysenteriae is the causative agent of swine dysentery, a disease with an important impact on pig production while B. pilosicoli is responsible of a milder diarrheal disease in these animals, porcine intestinal spirochetosis. Recent sequencing projects have provided information for the genome of these species facilitating the search of vaccine candidates using reverse vaccinology approaches. However, practically no experimental evidence exists of the actual gene products being expressed and of those proteins exposed on the cell surface or released to the cell media. Using a cell-shaving strategy and a shotgun proteomic approach we carried out a large-scale characterization of the exposed proteins on the bacterial surface in these species as well as of peptides and proteins in the extracellular medium. The study included three strains of B. hyodysenteriae and two strains of B. pilosicoli and involved 148 LC-MS/MS runs on a high resolution Orbitrap instrument. Overall, we provided evidence for more than 29,000 different peptides pointing to 1625 and 1338 different proteins in B. hyodysenteriae and B. pilosicoli, respectively. Many of the most abundant proteins detected corresponded to described virulence factors and vaccine candidates. The level of expression of these proteins, however, was different among species and strains, stressing the value of determining actual gene product levels as a complement of genomic-based approaches for vaccine design. PMID:27493641

  3. Density variation in fused silica exposed to femtosecond laser

    NASA Astrophysics Data System (ADS)

    Champion, Audrey; Bellouard, Yves

    2012-01-01

    Fused silica (a-SiO2) exposure to low-energy femtosecond laser pulses leads to interesting effects such as a local increase of etching rate and/or a local increase of refractive index. Up to now the exact modifications occurring in the glass matrix after exposure remains elusive and various hypotheses among which the formation of color centers or of densified zones have been proposed. In the densification model, shorter SiO2 rings form in the glass matrix leading to an enhanced etching rate. In this paper, we investigate quantitatively the amount of volume variation occurring in well-defined laser exposed areas. Our method is based on the deflection of glass cantilevers and hypotheses from classical beam theory. Specifically, 20-mm long cantilevers are fabricated using low-energy femtosecond laser pulses. After chemical etching, the cantilevers are exposed a second time to the same femtosecond laser but only in their upper-half thickness and this time, without a subsequent etching step. We observe micron-scale displacements at the cantilever tips that we use to estimate the volume variation in laser affected zones. Our results not only show that in the regime where nanogratings form (so called type II structures), laser affected zones expand but also provide a quantitative method to estimate the amount of stress as a function of the laser exposure parameters.

  4. Electromagnetic Compatibility Testing of Implantable Neurostimulators Exposed to Metal Detectors

    PubMed Central

    Seidman, Seth J; Kainz, Wolfgang; Casamento, Jon; Witters, Donald

    2010-01-01

    This paper presents results of electromagnetic compatibility (EMC) testing of three implantable neurostimulators exposed to the magnetic fields emitted from several walk-through and hand-held metal detectors. The motivation behind this testing comes from numerous adverse event reports involving active implantable medical devices (AIMDs) and security systems that have been received by the Food and Drug Administration (FDA). EMC testing was performed using three neurostimulators exposed to the emissions from 12 walk-through metal detectors (WTMDs) and 32 hand-held metal detectors (HHMDs). Emission measurements were performed on all HHMDs and WTMDs and summary data is presented. Results from the EMC testing indicate possible electromagnetic interference (EMI) between one of the neurostimulators and one WTMD and indicate that EMI between the three neurostimulators and HHMDs is unlikely. The results suggest that worst case situations for EMC testing are hard to predict and testing all major medical device modes and setting parameters are necessary to understand and characterize the EMC of AIMDs. PMID:20448818

  5. Thyroid neoplasia in Marshall Islanders exposed to nuclear fallout

    SciTech Connect

    Hamilton, T.E.; van Belle, G.; LoGerfo, J.P.

    1987-08-07

    We studied the risk of thyroid neoplasia in Marshall Islanders exposed to radioiodines in nuclear fallout from the 1954 BRAVO thermonuclear test. We screened 7266 Marshall Islanders for thyroid nodules; the islanders were from 14 atolls, including several southern atolls, which were the source of the best available unexposed comparison group. Using a retrospective cohort design, we determined the prevalence of thyroid nodularity in a subgroup of 2273 persons who were alive in 1954 and who therefore were potentially exposed to fallout from the BRAVO test. For those 12 atolls previously thought to be unexposed to fallout, the prevalence of thyroid nodules ranged from 0.9% to 10.6%. Using the distance of each atoll from the test site as a proxy for the radiation dose to the thyroid gland, a weighted linear regression showed an inverse linear relationship between distance and the age-adjusted prevalence of thyroid nodules. Distance was the strongest single predictor in logistic regression analysis. A new absolute risk estimate was calculated to be 1100 excess cases/Gy/y/1 X 10(6) persons (11.0 excess cases/rad/y/1 million persons), 33% higher than previous estimates. We conclude that an excess of thyroid nodules was not limited only to the two northern atolls but extended throughout the northern atolls; this suggests a linear dose-response relationship.

  6. Protection of chemolithoautotrophic bacteria exposed to simulated Mars environmental conditions

    NASA Astrophysics Data System (ADS)

    Gómez, Felipe; Mateo-Martí, Eva; Prieto-Ballesteros, Olga; Martín-Gago, Jose; Amils, Ricardo

    2010-10-01

    Current surface conditions (strong oxidative atmosphere, UV radiation, low temperatures and xeric conditions) on Mars are considered extremely challenging for life. The question is whether there are any features on Mars that could exert a protective effect against the sterilizing conditions detected on its surface. Potential habitability in the subsurface would increase if the overlaying material played a protective role. With the aim of evaluating this possibility we studied the viability of two microorganisms under different conditions in a Mars simulation chamber. An acidophilic chemolithotroph isolated from Río Tinto belonging to the Acidithiobacillus genus and Deinococcus radiodurans, a radiation resistant microorganism, were exposed to simulated Mars conditions under the protection of a layer of ferric oxides and hydroxides, a Mars regolith analogue. Samples of these microorganisms were exposed to UV radiation in Mars atmospheric conditions at different time intervals under the protection of 2 and 5 mm layers of oxidized iron minerals. Viability was evaluated by inoculation on fresh media and characterization of their growth cultures. Here we report the survival capability of both bacteria to simulated Mars environmental conditions.

  7. Neural Tube Defects In Mice Exposed To Tap Water

    PubMed Central

    Mallela, Murali K; Werre, Stephen R; Hrubec, Terry C

    2010-01-01

    In May of 2006 we suddenly began to observe neural tube defects (NTDs) in embryos of untreated control mice. We hypothesized the mice were being exposed unknowingly to a teratogenic agent and investigated the cause. Our results suggested that NTDs were not resulting from bedding material, feed, strain or source of the mice. Additionally, mice were negative for routine and comprehensive screens of pathogens. To further test whether the NTDs resulted from infectious or genetic cause localized to our facility, we obtained three strains of timed pregnant mice from commercial suppliers located in 4 different states. All strains and sources of mice arrived in our laboratory with NTDs, implying that commercially available mice were possibly exposed to a teratogen prior to purchase. Our investigation eventually concluded that exposure to tap water was causing the NTDs. The incidence of NTDs was greatest in purchased mice provided tap water and lowest in purchased mice provided distilled deionized water (DDI). Providing mice DDI water for two generations (F2-DDI) eliminated the NTDs. When F2-DDI mice were provided tap water from three different urban areas prior to breeding, their offspring again developed NTDs. Increased length of exposure to tap water significantly increased the incidence of NTDs. These results indicate that a contaminant in municipal tap water is likely causing NTDs in mice. The unknown teratogen appears to have a wide geographic distribution but has not yet been identified. Water analysis is currently underway to identify candidate contaminants that might be responsible for the malformations. PMID:20549630

  8. The Immune System of HIV-Exposed Uninfected Infants.

    PubMed

    Abu-Raya, Bahaa; Kollmann, Tobias R; Marchant, Arnaud; MacGillivray, Duncan M

    2016-01-01

    Infants born to human immunodeficiency virus (HIV) infected women are HIV-exposed but the majority remains uninfected [i.e., HIV-exposed uninfected (HEU)]. HEU infants suffer greater morbidity and mortality from infections compared to HIV-unexposed (HU) peers. The reason(s) for these worse outcomes are uncertain, but could be related to an altered immune system state. This review comprehensively summarizes the current literature investigating the adaptive and innate immune system of HEU infants. HEU infants have altered cell-mediated immunity, including impaired T-cell maturation with documented hypo- as well as hyper-responsiveness to T-cell activation. And although prevaccination vaccine-specific antibody levels are often lower in HEU than HU, most HEU infants mount adequate humoral immune response following primary vaccination with diphtheria toxoid, haemophilus influenzae type b, whole cell pertussis, measles, hepatitis B, tetanus toxoid, and pneumococcal conjugate vaccines. However, HEU infants are often found to have lower absolute neutrophil counts as compared to HU infants. On the other hand, an increase of innate immune cytokine production and expression of co-stimulatory markers has been noted in HEU infants, but this increase appears to be restricted to the first few weeks of life. The immune system of HEU children beyond infancy remains largely unexplored.

  9. Oxidative stress in songbirds exposed to dietary methylmercury.

    PubMed

    Henry, Katie A; Cristol, Daniel A; Varian-Ramos, Claire W; Bradley, Eric L

    2015-04-01

    Long-term, sublethal methylmercury exposure can cause reproductive depression, immune suppression, endocrine disruption and other problems in birds. We used two biomarkers to detect oxidative stress in livers of zebra finches (Taeniopygia guttata) developmentally exposed to sublethal levels of dietary methylmercury (0.0, 0.3, 0.6, 1.2, or 2.4 μg/g wet weight in diet). Our findings indicate that young adult finches exposed to environmentally relevant concentrations of mercury in ovo and through their diets, exhibited oxidative stress in their livers. We measured the ratio of the antioxidant glutathione in its reduced form (GSH) versus its oxidized form (GSSG) and the activity of the superoxide dismutase (SOD) enzyme suite. Blood total mercury served as a proxy for liver mercury concentration, and was on average 8.4 times the dietary dose (e.g., birds consuming 0.6 μg/g had blood mercury levels of ~5 μg/g on a wet weight basis). Consistent with what is known from large, aquatic bird species, there was a significant, negative relationship between GSH/GSSG ratios and tissue mercury concentrations, which is indicative of oxidative stress. This relationship was driven by a significant increase in the oxidized glutathione in the livers of birds with higher blood mercury levels. SOD activity was also found to have a significant, negative relationship with blood mercury.

  10. Juveniles exposed to embryonic corticosterone have enhanced flight performance

    PubMed Central

    Chin, Eunice H.; Love, Oliver P.; Verspoor, Jan J.; Williams, Tony D.; Rowley, Kyle; Burness, Gary

    2008-01-01

    Exposure to maternally derived glucocorticoids during embryonic development impacts offspring phenotype. Although many of these effects appear to be transiently ‘negative’, embryonic exposure to maternally derived stress hormones is hypothesized to induce preparative responses that increase survival prospects for offspring in low-quality environments; however, little is known about how maternal stress influences longer-term survival-related performance traits in free-living individuals. Using an experimental elevation of yolk corticosterone (embryonic signal of low maternal quality), we examined potential impacts of embryonic exposure to maternally derived stress on flight performance, wing loading, muscle morphology and muscle physiology in juvenile European starlings (Sturnus vulgaris). Here we report that fledglings exposed to experimentally increased corticosterone in ovo performed better during flight performance trials than control fledglings. Consistent with differences in performance, individuals exposed to elevated embryonic corticosterone fledged with lower wing loading and had heavier and more functionally mature flight muscles compared with control fledglings. Our results indicate that the positive effects on a survival-related trait in response to embryonic exposure to maternally derived stress hormones may balance some of the associated negative developmental costs that have recently been reported. Moreover, if embryonic experience is a good predictor of the quality or risk of future environments, a preparative phenotype associated with exposure to apparently negative stimuli during development may be adaptive. PMID:18842541

  11. Lipid peroxidation in workers exposed to hexavalent chromium.

    PubMed

    Huang, Y L; Chen, C Y; Sheu, J Y; Chuang, I C; Pan, J H; Lin, T H

    1999-02-26

    The aim of this study was to investigate whether exposure to hexavalent chromium induces lipid peroxidation in human. This study involved 25 chrome-plating factory workers and a reference group of 28 control subjects. The whole-blood and urinary chromium concentrations were determined by graphite furnace atomic absorption spectrophotometry. Malondialdehyde (MDA), the product of lipid peroxidation, was determined by high-performance liquid chromatography, and the activities of protective enzymes were measured by ultraviolet-visible spectrophotometry. In the chrome-plating workers, the mean concentrations of chromium in blood and urine were 5.98 microg/L and 5.25 microg/g creatinine, respectively; the mean concentrations of MDA in blood and urine were 1.7 micromol/L and 2.24 micromol/g creatinine. The concentrations of both chromium and MDA in blood and urine were significantly higher in the chromium-exposed workers. The activities of superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT) were not markedly different between control and exposed workers. Data suggest that MDA may be used as a biomarker for occupational chromium exposure. Antioxidant enzymic activities are not a suitable marker for chromium exposure.

  12. Exposing the cancer genome atlas as a SPARQL endpoint

    PubMed Central

    Deus, Helena F.; Veiga, Diogo F.; Freire, Pablo R.; Weinstein, John N.; Mills, Gordon B.; Almeida, Jonas S.

    2011-01-01

    The Cancer Genome Atlas (TCGA) is a multidisciplinary, multi-institutional effort to characterize several types of cancer. Datasets from biomedical domains such as TCGA present a particularly challenging task for those interested in dynamically aggregating its results because the data sources are typically both heterogeneous and distributed. The Linked Data best practices offer a solution to integrate and discover data with those characteristics, namely through exposure of data as Web services supporting SPARQL, the Resource Description Framework query language. Most SPARQL endpoints, however, cannot easily be queried by data experts. Furthermore, exposing experimental data as SPARQL endpoints remains a challenging task because, in most cases, data must first be converted to Resource Description Framework triples. In line with those requirements, we have developed an infrastructure to expose clinical, demographic and molecular data elements generated by TCGA as a SPARQL endpoint by assigning elements to entities of the Simple Sloppy Semantic Database (S3DB) management model. All components of the infrastructure are available as independent Representational State Transfer (REST) Web services to encourage reusability, and a simple interface was developed to automatically assemble SPARQL queries by navigating a representation of the TCGA domain. A key feature of the proposed solution that greatly facilitates assembly of SPARQL queries is the distinction between the TCGA domain descriptors and data elements. Furthermore, the use of the S3DB management model as a mediator enables queries to both public and protected data without the need for prior submission to a single data source. PMID:20851208

  13. Turning Rate Dynamics of Zebrafish Exposed to Ethanol

    NASA Astrophysics Data System (ADS)

    Mwaffo, Violet; Porfiri, Maurizio

    2015-06-01

    Zebrafish is emerging as a species of choice in alcohol-related pharmacological studies. In these studies, zebrafish are often exposed to acute ethanol treatments and their activity scored during behavioral assays. Computational modeling of zebrafish behavior is expected to positively impact these efforts by offering a predictive toolbox to plan hypothesis-driven studies, reduce the number of subjects, perform pilot trials, and refine behavioral screening. In this work, we demonstrate the use of the recently proposed jump persistent turning walker to model the turning rate dynamics of zebrafish exposed to acute ethanol administration. This modeling framework is based on a stochastic mean reverting jump process to capture the sudden and large changes in orientation of swimming zebrafish. The model is calibrated on an available experimental dataset of 40 subjects, tested at different ethanol concentrations. We demonstrate that model parameters are modulated by ethanol administration, whereby both the relaxation rate and jump frequency of the turning rate dynamics are influenced by ethanol concentration. This effort offers a first evidence for the possibility of complementing zebrafish pharmacological research with computational modeling of animal behavior.

  14. Experiences of being exposed to intimate partner violence during pregnancy

    PubMed Central

    Lidén, Eva; Lundgren, Ingela

    2012-01-01

    In this study a phenomenological approach was used in order to enter deeply into the experience of living with violence during pregnancy. The aim of the study was to gain a deeper understanding of women's experiences of being exposed to intimate partner violence (IPV) during pregnancy. The data were collected through in-depth interviews with five Norwegian women; two during pregnancy and three after the birth. The women were between the age of 20 and 38 years. All women had received support from a professional research and treatment centre. The essential structure shows that IPV during pregnancy is characterized by difficult existential choices related to ambivalence. Existential choices mean questioning one's existence, the meaning of life as well as one's responsibility for oneself and others. Five constituents further explain the essential structure: Living in unpredictability, the violence is living in the body, losing oneself, feeling lonely and being pregnant leads to change. Future life with the child is experienced as a possibility for existential change. It is important for health professionals to recognize and support pregnant women who are exposed to violence as well as treating their bodies with care and respect. PMID:22468147

  15. Growth characteristics of maize seeds exposed to magnetic field.

    PubMed

    Vashisth, Ananta; Joshi, Devendra Kumar

    2017-02-01

    Standardization of magnetic field was done for maximum enhancement in germination characteristics of maize seeds. Seeds of maize were exposed to static magnetic fields of strength 50, 100, 150, 200, and 250 for 1, 2, 3, and 4 h for all field strengths. Results indicate that magnetic field application enhanced seed performance in terms of percentage germination, speed of germination, seedling length, and seedling dry weight significantly compared to unexposed control. Among the various combinations of field strength and duration, 200 mT for 1 h exposure gave best results. Exposure of seeds to magnetic fields improved seed coat membrane integrity as it reduced cellular leakage and, consequently, electrical conductivity. Experiments conducted at a research farm as well as farmer's field showed that plants raised from seeds exposed to 200 mT for 1 h had higher values of leaf area index, shoot length, number of leaves, chlorophyll content, shoot/root dry weight, and root characteristics as compared to corresponding values in untreated control. From the studies, it may be concluded that exposure of dry seeds to static magnetic field of 200 mT for 1 h improved shoot and root growth. Improved root system and biomass led to increased seed yield. Improved functional root parameters suggested that magnetically treated maize seeds could be used under moisture stress conditions. Bioelectromagnetics. 38:151-157, 2017. © 2016 Wiley Periodicals, Inc.

  16. Exposing public health surveillance data using existing standards.

    PubMed

    Turbelin, Clément; Boëlle, Pierre-Yves

    2013-01-01

    With the growing use of information technologies, an increased volume of data is produced in Public Health Surveillance, enabling utilization of new data sources and analysis methods. Public health and research will benefit from the use of data standards promoting harmonization and data description through metadata. No data standard has yet been universally accepted for exchanging public health data. In this work, we implemented two existing standards eligible to expose public health data: Statistical Data and Metadata Exchange - Health Domain (SDMX-HD) proposed by the World Health Organization and Open Data Protocol (OData) proposed by Microsoft Corp. SDMX-HD promotes harmonization through controlled vocabulary and predefined data structure suitable for public health but requires important investment, while OData, a generic purpose standard, proposes a simple way to expose data with minimal documentation and end-user integration tools. The two solutions were implemented and are publicly available at http://sdmx.sentiweb.fr and http://odata.sentiweb.fr. These solutions show that data sharing and interoperability are already possible in Public Health Surveillance.

  17. Error-Related Negativities During Spelling Judgments Expose Orthographic Knowledge

    PubMed Central

    Harris, Lindsay N.; Perfetti, Charles A.; Rickles, Benjamin

    2014-01-01

    In two experiments, we demonstrate that error-related negativities (ERNs) recorded during spelling decisions can expose individual differences in lexical knowledge. The first experiment found that the ERN was elicited during spelling decisions and that its magnitude was correlated with independent measures of subjects’ spelling knowledge. In the second experiment, we manipulated the phonology of misspelled stimuli and observed that ERN magnitudes were larger when misspelled words altered the phonology of their correctly spelled counterparts than when they preserved it. Thus, when an error is made in a decision about spelling, the brain processes indexed by the ERN reflect both phonological and orthographic input to the decision process. In both experiments, ERN effect sizes were correlated with assessments of lexical knowledge and reading, including offline spelling ability and spelling-mediated vocabulary knowledge. These results affirm the interdependent nature of orthographic, semantic, and phonological knowledge components while showing that spelling knowledge uniquely influences the ERN during spelling decisions. Finally, the study demonstrates the value of ERNs in exposing individual differences in lexical knowledge. PMID:24389506

  18. Cerebral blood flow in patients (PTS) exposed to neurotoxic chemicals

    SciTech Connect

    Heuser, G.; Mena, I.; Thomas, C.

    1994-05-01

    Exposure to neurotoxic chemicals as pesticides, glues, solvents, etc. are known to induce neurologic and psychiatric symptomatology. We report on 72 pts, 33 young pts, 8 males, and 26 females, age 55 (7) yrs, 15 of them exposed to pesticides, and 37 to solvents. They were studied with quantitative and qualitative analysis of rCBF performed with 30 mCi of Xe-133 (Xe) by inhalation followed by 30 mCi of Tc-HMPAO given IV. Imaging was performed with a brain dedicated system, and distribution of rCBF was assessed with automatic ROI definition, and HMPAO normalized to maximal pixel activity in the brain. Results of Xe rCBF are expressed as mean and (S.D.) in ml/min/100g, and HMPAO as mean and (S.D.) uptake per ROI and compared with age-matched controls, 10 young and 20 elderly individuals, and also to a group of 36 elderly chronic fatigue pts (CFS), and 26 depression pts. CBF was diminished in young and elderly, 45 (7) and 40 (7) ml/min 100g, p<0.02 for both groups. Thus we conclude that pts exposed to chemicals present with diminished CBF, worse in elderly in the right dorsal frontal and parietal lobes, and in young, in left dorsal frontal and temporal lobes. These findings are significantly different from observations in pts and chronic fatigue and depression.

  19. Eye Lens Opacities Among Physicians Occupationally Exposed to Ionizing Radiation.

    PubMed

    Auvinen, Anssi; Kivelä, Tero; Heinävaara, Sirpa; Mrena, Samy

    2015-08-01

    We compared the frequency of lens opacities among physicians with and without occupational exposure to ionizing radiation, and estimated dose-response between cumulative dose and opacities. We conducted ophthalmologic examinations of 21 physicians with occupational exposure to radiation and 16 unexposed physicians. Information on cumulative radiation doses (mean 111 mSv) was based on dosimeter readings recorded in a national database on occupational exposures. Lens changes were evaluated using the Lens Opacities Classification System II, with an emphasis on posterior subcapsular (PSC) and cortical changes. Among the exposed physicians, the prevalences of cortical and PSC changes were both 11% (3/21), and the corresponding frequencies in the unexposed group were 44% (n = 7) and 6% (n = 1). For dose-response analysis, the data were pooled with 29 exposed physicians from our previous study. No association of either type of lens changes with cumulative recorded dose was observed. Our findings do not indicate an increased frequency of lens opacities in physicians with occupational exposure to ionizing radiation. However, the subjects in this study have received relatively low doses and therefore the results do not exclude small increases in lens opacities or contradict the studies reporting increases among interventional cardiologists with materially higher cumulative doses.

  20. Test system for exposing fish to resuspended, contaminated sediment

    USGS Publications Warehouse

    Cope, W.G.; Wiener, J.G.; Steingraeber, M.T.

    1996-01-01

    We describe a new test system for exposing fish to resuspended sediments and associated contaminants. Test sediments were resuspended by revolving test chambers on rotating shafts driven by an electric motor. The timing, speed, and duration of test-chamber revolution were controlled by a rheostat and electronic timer. Each chamber held 45 litres of water and accommodated about 49 g of test fish. The system described had three water baths, each holding six test chambers. We illustrate the performance of this system with results from a 28-day test in which juvenile bluegills Lepomis macrochirus were exposed to resuspended, riverine sediments differing in texture and cadmium content. The test had one sediment-free control and five sediment treatments, with three replicates (chambers) per treatment and 25 fish per replicate. Two-thirds (30 litres) of the test water and sediment in each chamber was renewed weekly. The mean concentration of total suspended solids (TSS) did not vary among treatments; the grand-mean TSS in the five sediment treatments was 975 mg litre-1, similar to the target TSS of 1000 mg litre-1. At the end of the test, an average of 50% of the introduced cadmium was associated with the suspended sediment compartment, whereas the filtered (0.45 μm) water contained 0.4% and bluegills 1.8% of the cadmium.

  1. Increased gluconeogenesis in rats exposed to hyper-G stress

    NASA Technical Reports Server (NTRS)

    Daligcon, B. C.; Oyama, J.; Hannak, K.

    1985-01-01

    The effect of gluconeogenesis on the levels of plasma glucose and liver glycogen was studied in rats exposed to hyper-G stress. Incorporation of lactate, alanine, or glycerol, labeled with C-14, into plasma glucose and liver glycogen was measured in rats centrifuged at 3.1 G for 0.25, 0.50, and 1.0-hr periods, and was compared to noncentrifuged controls injected with appropriate glycogen precursors. It was found that exposure to G-stress leads to increased incorporation from all three substrates into both plasma glucose and liver glycogen. These early incorporation increases were blocked upon pre-G administration of 5-methoxyindole-2-carboxylic acid, a gluconeogenesis inhibitor, or propanolol, a beta-adrenergic blocker, as well as by adrenodemedullation. Results indicate that the rapid rise in plasma glucose, as well as in liver glycogen in rats exposed to hyper-G stress is due to an increased rate of gluconeogenesis, and that epinephrine, released in response to hyper-G-induced activation of the sympathetic-adrenal system, plays a dominant role during the early stages of hyper-G stress.

  2. HIV Exposed Infants: Rethinking care for a lifelong condition

    PubMed Central

    Sugandhi, N; Rodrigues, J; Kim, MH; Ahmed, S; Amzel, A; Tolle, M; Dzubien, E; Rivadeneira, E; Kellerman, S

    2014-01-01

    Summary Each year over a million infants are born to HIV infected mothers though with scale up of prevention of mother to child transmission (PMTCT) interventions, only 210,000 of the 1.3 million infants born to mothers with HIV/AIDS in 2012 became infected. Current programmatic efforts directed at infants born to HIV-infected mothers are primarily focused on decreasing their risk of infection, but this emphasis on maternal interventions has meant follow-up of exposed infants has been poor. Programs are struggling to retain this population in care until the end of exposure, typically at the cessation of breastfeeding, between 12 and 24 months of age. But HIV exposure is a life-long condition that continues to impact the health and well-being of a child long after exposure has ended. A better understanding of the impact of HIV on exposed infants is needed and new programs and interventions must take into consideration the long-term health needs of this growing population. The introduction of lifelong treatment for all HIV-infected pregnant women is an opportunity to rethink how we provide services adapted for the long-term retention of mother-infant pairs. PMID:24361628

  3. [Protection of cadaver tissues exposed to high gamma radiation].

    PubMed

    Matus-Jiménez, J; Flores-Fletes, J R; Carrillo, A

    2013-01-01

    Bone tissue is the most widely used tissue for the treatment of various conditions. As a result of this, allografts are used at an increasing frequency and processes for their harvest, preservation and sterilization have improved. The sterilization method that grants the greatest sterilization is high-dose gamma radiation, which destroys prions and any microorganism thus assuring that patients will not experience any infection. But given that radiation use has proven to deteriorate bone and tendon tissue, efforts have been made to protect the latter. One way to do this is a commercially available substance called Clearant. Studies conducted elsewhere have found that it does protect bone and tendon tissue. This study was therefore conducted with allograft samples exposed to high-dose radiation. Its purpose was to assess, with photon microscopy using various dyes and electron microscopy, the presence of color changes as well as the destruction of the anatomical structure. The same tissue was followed-up throughout the process until it was placed in the patient. The review found no structural changes in bone and tendon tissues exposed to high radiation doses (60 kilograys) when the Clearant process was used, and concluded that the former may be used safely in orthopedic or traumatologic diseases.

  4. The ORGANIC experiment on EXPOSE-R on the ISS: Flight sample preparation and ground control spectroscopy

    NASA Astrophysics Data System (ADS)

    Bryson, K. L.; Peeters, Z.; Salama, F.; Foing, B.; Ehrenfreund, P.; Ricco, A. J.; Jessberger, E.; Bischoff, A.; Breitfellner, M.; Schmidt, W.; Robert, F.

    2011-12-01

    In March of 2009, the ORGANIC experiment integrated into the European multi-user facility EXPOSE-R, containing experiments dedicated to Astrobiology, was mounted through Extra Vehicular Activity (EVA) externally on the International Space Station (ISS). The experiment exposed organic samples of astronomical interest for a duration of 97 weeks (˜22 months) to the space environment. The samples that were returned to Earth in spring 2011, received a total UV radiation dose during their exposure including direct solar irradiation of >2500 h, exceeding the limits of laboratory simulations. We report flight sample preparation and pre-flight ultraviolet-visible (UV-Vis) characterization of the ORGANIC samples, which include 11 polycyclic aromatic hydrocarbons (PAHs) and three fullerenes. The corresponding time-dependent ground control monitoring experiments for ORGANIC measured over ˜19 months are presented and the results anticipated upon return of the samples are discussed. We present the first UV-Vis spectrum of solid circobiphenyl (C 38H 16). Further, we present the first published UV-Vis spectra of diphenanthro[9,10-b',10'-d]thiophene (C 28H 16S), dinaphtho[8,1,2-abc,2',1',8'-klm]coronene (C 36H 16), tetrabenzo[de,no,st,c'd']heptacene (C 42H 22), and dibenzo[jk,a'b']octacene (C 40H 22) in solid phase and in solution. The results of the ORGANIC experiment are expected to enhance our knowledge of the evolution and degradation of large carbon-containing molecules in space environments.

  5. Analysing deterioration of marble stones exposed to underwater conditions

    NASA Astrophysics Data System (ADS)

    Cámara, Beatriz; Álvarez de Buergo, Mónica; Bethencourt, Manuel; Freire-Lista, David; Fort, Rafael

    2016-04-01

    The peculiar conditions of the marine environment make the conservation of underwater archaeological sites an extremely complex procedure. This is due to the fact that the prevailing conditions in this environment promote the development of deterioration phenomena in submerged artefacts through the synergistic action of physical, chemical and biological factors. The objective of the present investigation was to determine how petrophysical properties of cultural heritage materials can be affected by being exposed to the specific underwater conditions of the sea bottom, and so, to evaluate how this can affect, in a long term, in their durability and evolution when they part of an archaeological site. For this purpose, two types of marble (the Italian Carrara and the Spanish Macael) were subjected to an experiment consisting of exposing stone materials for one and a half year to underwater conditions. The experimental test was located in an archaeological site in the Bay of Cadiz (southern Spain), Bajo del Chapitel (recognized as Cultural Interest), which includes remains of shipwrecks from different periods. In this site, samples were submerged to 12 m depth and placed in the sea bottom simulating the different positions in which underwater archaeological objects can be found (fully exposed, half buried and covered). Petrophysical characterisation involved determination of the apparent and bulk densities, water saturation (maximum water content a material may contain), open porosity (porosity accessible to water), chromatic parameters and ultrasonic velocity. Before measuring, samples were subjected to mechanical cleaning (in those samples with biological colonization) and to removal of salt deposits. Results showed significant differences in these petrophysical properties after underwater submersion, which were directly related to the type of underwater exposure condition. Comparative analysis of petrophysical properties, like the one conducted in this study

  6. Cytogenetic Monitoring of Farmers exposed to pesticides in Colombia.

    PubMed Central

    Hoyos, L S; Carvajal, S; Solano, L; Rodriguez, J; Orozco, L; López, Y; Au, W W

    1996-01-01

    We have monitored 30 pesticide-exposed workers and 30 matched controls for expression of chromosome aberrations (CA) and sister chromatid exchanges (SCE) in their lymphocytes. Peripheral blood cultures were set up within 3 hr after the collection of samples, and four cultures were set up from each donor. For CA analysis, 100 complete metaphase cells from each donor were evaluated. For the SCE assay, 50 complete metaphase cells from each donor were analyzed. The CA and SCE data were analyzed for differences between the two groups using the chi 2 and the Student's t-test, respectively. From the CA analysis it was obvious that the overwhelming majority of aberrations were chromatid breaks and isochromatid breaks; therefore, only these data are presented and used for statistical analysis. Isochromatid breaks were counted as two breaks each and chromatid breaks as one in calculating the total chromatid break frequencies. Statistical evaluation of the data indicates that there is no significant difference (p > 0.05; chi 2 test) between the exposed and the nonexposed groups based on chromatid breaks per 100 cells (1.2 +/- 0.3 and 1.5 +/- 0.2, respectively) and total chromatid breaks per 100 cells (1.7 +/- 0.3 and 2.1 +/- 0.2, respectively). No significantly difference between the two groups (p > 0.05, Student's t-test) was observed with SCE frequencies (5.0 +/- 1.1 and 4.8 +/- 0.9, respectively). Linear regression analysis indicates that the data were not influenced by age, cigarette smoking, or alcohol consumption. It is assuring that the exposure conditions among these Indian farmers have not caused detectable increases of chromosome damage using standard assays; this suggests the lack of serious long-term health problems. However, periodic monitoring of such exposed populations should be conducted using the same or other more sensitive assays. In addition, other populations with exposure to different types of pesticides in Colombia should also be investigated. PMID

  7. Genotoxic damage in pathology anatomy laboratory workers exposed to formaldehyde.

    PubMed

    Costa, Solange; Coelho, Patrícia; Costa, Carla; Silva, Susana; Mayan, Olga; Santos, Luís Silva; Gaspar, Jorge; Teixeira, João Paulo

    2008-10-30

    Formaldehyde (FA) is a chemical traditionally used in pathology and anatomy laboratories as a tissue preservative. Several epidemiological studies of occupational exposure to FA have indicated an increased risk of nasopharyngeal cancers in industrial workers, embalmers and pathology anatomists. There is also a clear evidence of nasal squamous cell carcinomas from inhalation studies in the rat. The postulated mode of action for nasal tumours in rats was considered biologically plausible and considered likely to be relevant to humans. Based on the available data IARC, the International Agency for Research on Cancer, has recently classified FA as a human carcinogen. Although the in vitro genotoxic as well as the in vivo carcinogenic potentials of FA are well documented in mammalian cells and in rodents, evidence for genotoxic effects and carcinogenic properties in humans is insufficient and conflicting thus remains to be more documented. To evaluate the genetic effects of long-term occupational exposure to FA a group of 30 Pathological Anatomy laboratory workers was tested for a variety of biological endpoints, cytogenetic tests (micronuclei, MN; sister chromatid exchange, SCE) and comet assay. The level of exposure to FA was evaluated near the breathing zone of workers, time weighted average of exposure was calculated for each subject. The association between the biomarkers and polymorphic genes of xenobiotic metabolising and DNA repair enzymes was also assessed. The mean level of exposure was 0.44+/-0.08ppm (0.04-1.58ppm). MN frequency was significantly higher (p=0.003) in the exposed subjects (5.47+/-0.76) when compared with controls (3.27+/-0.69). SCE mean value was significantly higher (p<0.05) among the exposed group (6.13+/-0.29) compared with control group (4.49+/-0.16). Comet assay data showed a significant increase (p<0.05) of TL in FA-exposed workers (60.00+/-2.31) with respect to the control group (41.85+/-1.97). A positive correlation was found between FA

  8. Genetic Analysis of Mice Skin Exposed by Hyper-Gravity

    NASA Astrophysics Data System (ADS)

    Takahashi, Rika; Terada, Masahiro; Seki, Masaya; Higashibata, Akira; Majima, Hideyuki J.; Ohira, Yoshinobu; Mukai, Chiaki; Ishioka, Noriaki

    2013-02-01

    In the space environment, physiological alterations, such as low bone density, muscle weakness and decreased immunity, are caused by microgravity and cosmic radiation. On the other hand, it is known that the leg muscles are hypertrophy by 2G-gravity. An understanding of the effects on human body from microgravity to hyper-gravity is very important. Recently, the Japan Aerospace Exploration Agency (JAXA) has started a project to detect the changes on gene expression and mineral metabolism caused by microgravity by analyzing the hair of astronauts who stay in the international Space Station (ISS) for a long time. From these results of human hair’s research, the genetic effects of human hair roots by microgravity will become clear. However, it is unclear how the gene expression of hair roots was effected by hypergravity. Therefore, in this experiment, we analyzed the effect on mice skin contained hair roots by comparing microgravity or hypergravity exposed mice. The purpose of this experiment is to evaluate the genetic effects on mice skin by microgravity or 2G-gravity. The samples were taken from mice exposed to space flight (FL) or hypergravity environment (2G) for 3-months, respectively. The extracted and amplified RNA from these mice skin was used to DNA microarray analysis. in this experiment, we analyzed the effect of gravity by using mice skin contained hair roots, which exposed space (FL) and hyper-gravity (2G) for 3 months and each control. By DNA microarray analysis, we found the common 98 genes changed in both FL and 2G. Among these 98 genes, the functions and pathways were identified by Gene Ontology (GO) analysis and Ingenuity Pathways Analysis (IPA) software. Next, we focused the one of the identified pathways and compared the effects on each molecules in this pathways by the different environments, such as FL and 2G. As the results, we could detect some interesting molecules, which might be depended on the gravity levels. In addition, to investigate

  9. Eighteen cases exposed to sarin in Matsumoto, Japan.

    PubMed

    Suzuki, J; Kohno, T; Tsukagosi, M; Furuhata, T; Yamazaki, K

    1997-07-01

    Forty-six patients who were exposed to sarin consulted our hospital because of darkness of vision, and ocular pain, vomiting, dyspnea and headaches on June 27 and 28, 1994. Eighteen patients were admitted and 4 of them were in the critical state. There were 6 features: 1) depression of plasma cholinesterase activity (17 of 18 patients, 94%), 2) hypokalemia (4/18, 22%), 3) depression of triglyceride (12/18, 67%), 4) hypocapnia (5/17, 29%), 5) partial pressure of oxygen (PaO2) <80 mmHg, or requirement of O2 inhalation (15/18, 83%), 6) white blood cells (WBC) >9,000 per mm3 (13/18, 72%). Seventeen patients were discharged from hospital, but one patient is still suffering from akinetic mutism after two years.

  10. Assessment of renal function in workers previously exposed to cadmium.

    PubMed Central

    Elinder, C G; Edling, C; Lindberg, E; Kågedal, B; Vesterberg, O

    1985-01-01

    Cadmium induced renal effects were examined in 60 workers (58 men, 2 women) previously exposed to cadmium. Tubular damage in the form of beta 2-microglobulinuria was found in 40%, and urinary albumin and orosomucoid increased significantly with increasing urinary cadmium and increasing relative clearance of beta 2-microglobulin. It is suggested that increased albumin excretion is secondary to the tubular damage. In no case was typical glomerular proteinuria found that could be related to cadmium. Histories of renal stones were more common among the workers with high urinary cadmium concentrations. The glomerular filtration rate was measured in 17 of the workers who had pronounced tubular dysfunction. The average glomerular filtration rate for these men was less than the age adjusted predicted value (mean = 84%). Furthermore, there was a significant (p less than 0.05) correlation (r = -0.47) between tubular reabsorption loss and a decreased glomerular filtration rate. PMID:3904816

  11. Sexual orientation of male mouse offspring prenatally exposed to ethanol.

    PubMed

    Watabe, T; Endo, A

    1994-01-01

    Pregnant mice were intubated with either low (2 g/kg) or high (4 g/kg) dose of ethanol twice daily throughout the last third of the gestational period (from dg14 to dg18: gestational day; plug positive = dg 0). Ninety days after birth, the sexual orientation test was conducted on male offspring. This test was designed to observe a two-choice preference for either male or female partners in a setting in which the test animal could move freely between the two incentive compartments within which a stud male and an estrous female had been placed. We found that young adult males that had been exposed to ethanol prenatally have a decreased preference for the opposite sex and an increased preference for the same sex as a partner, although their physical development was apparently unaffected.

  12. Oxyhemoglobin photodissociation efficiency in biological tissue exposed to laser radiation

    NASA Astrophysics Data System (ADS)

    Barun, V. V.; Ivanov, A. P.

    2011-09-01

    We have obtained quantitative data on the differential (with respect to depth) and the integrated oxyhemoglobin photodissociation efficiency in the dermis when the skin surface is exposed to a light beam in the wavelength range 300-650 nm. With this aim, we have used our own previously developed optical model for skin tissue and analytical procedure for calculating the characteristics of optical fields in a medium. We have estimated the number of oxygen molecules formed at different depths in the medium, and also their integrated number over the entire thickness of the dermis as a function of the irradiation wavelength. We consider models for a dermis that is homogeneous with respect to depth and a dermis that has a layered structure. We show that the spectral photodissociation efficiency has a number of maxima associated with the absorption spectrum of oxyhemoglobin and the optical properties of all the layers of skin tissue. We discuss the effect of the epidermis on these maxima.

  13. Reproductive adaptation in Drosophila exposed to oxygen-enriched atmospheres

    NASA Technical Reports Server (NTRS)

    Kloek, G.; Winkle, L.

    1979-01-01

    Ten successive generations of a Drosophila melanogaster population were exposed to an atmospheric mix of 50% oxygen/50% nitrogen at standard pressure. This atmospheric mix has been shown to be toxic to this species and causes significantly shortened life span. By the fifth generation, survivorship and life span for the first 25-30 days were identical to control populations and total life span was shorter by only a few days. Egg-laying rates were stable in the experimental populations but below those of the controls. Hatching success was identical between experimental and control populations. Even though the egg-laying rates were lower in 50% oxygen, it was concluded that the population had adapted and could maintain a stable population in these conditions. The near-normal life spans, normal hatching rates, and overall population stability, exhibited following five generations of adaptation, were considered sufficient to allow continued reproduction in spite of a reduced egg-laying rate.

  14. DNA damage in Wistar rats exposed to dithiocarbamate pesticide mancozeb.

    PubMed

    Goldoni, A; Klauck, C R; Da Silva, S T; Da Silva, M D; Ardenghi, P G; Da Silva, L B

    2014-01-01

    Pesticides are used in large amounts in agriculture and the evaluation of their toxic effects is of major concern to public and environmental health. The aim of the present study was to investigate the genotoxic potential of a commercial formulation of the fungicide mancozeb by the micronucleus test in bone marrow and the comet assay in total blood of Wistar rats. Adult male Wistar rats were treated with a solution of mancozeb at a concentration of 40 mg/kg/day, administered intraperitoneally for 18 consecutive days, and compared to a control group. The results indicate that mancozeb induced significantly higher DNA damage as detected by the comet assay and increased the frequency of micronuclei. The results show that mancozeb is genotoxic and may adversely affect the DNA integrity of exposed organisms.

  15. Nanoindentation Study of Na-Geopolymers Exposed to High Temperatures

    NASA Astrophysics Data System (ADS)

    Beleña, I.; Zhu, W.

    This paper reports the usefulness of nanoindentation as a characterization and monitoring tool for studying thermal behaviour of Geopolymer materials. The influence of the manufacturing process of Na-Geopolymers in their micro-mechanical properties and thermal behaviour has been studied. Two types of metakaolin-based geopolymer panels with almost identical composition were prepared by injection and pouring methods. Micro-mechanical properties of the two samples exposed to high temperatures up to 1000 ºC were studied by nanoindentation technique, supplemented by X-ray diffraction (XRD), Nuclear magnetic resonance (NMR), Thermogravimetric analysis (TGA) and Microscopy. Remarkable differences in micro-mechanical properties and thermal behaviour between the two samples were found. Statistical nanoindentation has been successfully used to provide information about the micro-mechanical properties of different phases in the material and their volume distributions.

  16. Wear of connector contacts exposed to relative motion

    NASA Astrophysics Data System (ADS)

    Wilk, R. A.

    Connectors play a significant role in the performance, cost, and reliability of electronic equipment. In connection with the development of the system interconnection design, a factor which is often overlooked is related to the importance of connector selection and mounting to minimize relative motion between contacts during vibration encountered in handling, transportation, and service. This motion can lead to the loss of protective coatings (gold and nickel) due to frictional wear. If this happens, fretting corrosion of the base metals may occur. The produced damage can adversely affect performance due to increased joint resistance, eventually causing intermittent contacts. The present investigation is concerned with the study of different style contacts (tuning fork, box, and circular) to determine their endurance and wear characteristics when exposed to relative motion created by vibration. All contacts investigated were fabricated from brass, beryllium copper, or phosphor bronze, and had .00127 mm minimum gold plating over .00127 mm minimum nickel plating.

  17. Developmental arrest in grass shrimp embryos exposed to selected toxicants

    SciTech Connect

    Wilson, J.E.H.

    1998-12-31

    Excised embryos of the grass shrimp (Palaemonetes pugio) were exposed to single pulse concentrations of selected pollutants for 4 days. The following toxicity endpoints were monitored: rate of embryonic development, embryo mortality, and types of embryo malformation. Each endpoint exhibited concentration--response relationships which were modified by the embryonic age at which exposure commenced. Developmental retardation of up to 3 days was effected by phenol at 0.01% (V/V) and complete developmental arrest occurred at 0.05% and 0.1% (V/V). Similarly for methylene chloride, developmental retardation of 1003 days were observed at 0.1% (V/V) depending on the age of the embryos at the start of the tests. The morphological abnormalities of the embryos are described. The ecological significance of these findings and implications for the development of short-term toxicity tests using grass shrimp embryos are discussed.

  18. Oxidative status in rat kidney exposed to petroleum hydrocarbons

    PubMed Central

    Azeez, Oyebisi M.; Akhigbe, Roland E.; Anigbogu, Chikodi N.

    2013-01-01

    Objective: The study investigates the possible role of oxidative stress on renal tissues in association with petroleum hydrocarbon-induced nephrotoxicity. Materials and Methods: Rats of comparable weights were randomly distributed into 10 groups: Control and groups exposed to kerosene, petrol, and diesel via inhalation, contamination by food, and contamination by water. The exposure lasted for eight weeks. Results: Exposure to petroleum hydrocarbon led to significant rise in serum urea and creatinine, and renal tissue malondialdehyde. It also caused significant reduction in urinary urea and creatinine, and reduced glutathione, superoxide dismutase, and catalase activities of renal tissue homogenate. However, serum and urine concentrations of albumin and total protein were comparable in all groups. Conclusion: Results from this study shows that exposure to petroleum hydrocarbon led to renal dysfunction via oxidative stress, increasing lipid peroxidation and reducing the antioxidant defense mechanism. PMID:23633852

  19. Magical Empiricism and 'Exposed Being' in Medicine and Traditional Healing.

    PubMed

    Thornton, Robert

    2015-01-01

    Southern African traditional healers often generalize too broadly from discrete ('accidental') instances of success, partly to recruit a clientele, while biomedicine frequently reasons incorrectly from the general to the specific. Both logics are based on empirical observations, but are inversions of each other; these I characterize as 'magical empiricism.' 'Magic' functions as a metapragmatic discourse to recruit a clientele from a skeptical public that doubts the efficacy of any therapeutic interventions, and it acts in parallel with other practical (and efficacious) healing acts. I introduce the concept of 'exposed beings' to describe locally specific constructions of the person as patient and healer. This helps to explain the existence and enduring appeal of many different medical practices and beliefs in South Africa, but I suggest that 'medical parallelism' rather than 'pluralism' might be more accurate.

  20. Decreased serum ceruloplasmin concentration in aluminum welders exposed to ozone.

    PubMed

    Pierre, F; Baruthio, F; Diebold, F; Wild, P; Goutet, M

    1988-01-01

    During an epidemiological survey on arc welders, serum copper and ceruloplasmin were determined in two groups of workers. One group consisted of aluminum welders who were divided into two groups: 13 welders working inside aluminum tanks (confined atmosphere) and 8 welders engaged in the production of vans for dump trucks (nonconfined atmosphere). The reference group consisted of 26 workers of the same plant who were not exposed to welding fumes. Ozone, the major pollutant in aluminum arc welding, was thought to be the principal factor in the significant decrease (P less than 0.01) of mean ceruloplasmin in confined welders. This decrease in the level of ceruloplasmin was still within the reference values and was not linked to age or to tobacco consumption. We found a linear relationship between ceruloplasmin concentration and the cumulated worktime along the week. This effect could be a sign in the serum of a lung reaction against oxidant activity in this type occupational exposure.

  1. Developmental effects of exposing Drosophila embryos to ether vapour.

    PubMed

    Bownes, M; Seiler, M

    1977-01-01

    Drosophila embryos at precise developmental stages were exposed to ether vapour. The defects in the resulting embryos and adults were observed. Ether disrupted embroygenesis in specific ways, causing defects primarily at the anterior of the embryo and disorganizing the arrangement of the segments. Adults showed deficiencies and duplications of many imaginal disc and histoblast derivatives. Phenocopies of the bithorax mutation which transforms metathorax to mesothorax were observed. They were first induced at the syncytial blastoderm stage, had their peak of production at the cellular blastoderm, and were no longer observed after the anterior and posterior midgut were partially invaginated. It was observed that not only are the halter/wing transformations confined to the anterior compartment, but also leg 3 to leg 2 transformations only occurred in the anterior leg compartment.

  2. Lack of exposed ice inside lunar south pole Shackleton Crater.

    PubMed

    Haruyama, Junichi; Ohtake, Makiko; Matsunaga, Tsuneo; Morota, Tomokatsu; Honda, Chikatoshi; Yokota, Yasuhiro; Pieters, Carle M; Hara, Seiichi; Hioki, Kazuyuki; Saiki, Kazuto; Miyamoto, Hideaki; Iwasaki, Akira; Abe, Masanao; Ogawa, Yoshiko; Takeda, Hiroshi; Shirao, Motomaro; Yamaji, Atsushi; Josset, Jean-Luc

    2008-11-07

    The inside of Shackleton Crater at the lunar south pole is permanently shadowed; it has been inferred to hold water-ice deposits. The Terrain Camera (TC), a 10-meter-resolution stereo camera onboard the Selenological and Engineering Explorer (SELENE) spacecraft, succeeded in imaging the inside of the crater, which was faintly lit by sunlight scattered from the upper inner wall near the rim. The estimated temperature of the crater floor, based on the crater shape model derived from the TC data, is less than approximately 90 kelvin, cold enough to hold water-ice. However, at the TC's spatial resolution, the derived albedo indicates that exposed relatively pure water-ice deposits are not on the crater floor. Water-ice may be disseminated and mixed with soil over a small percentage of the area or may not exist at all.

  3. Morbidity and mortality in talc-exposed workers.

    PubMed

    Wergeland, E; Andersen, A; Baerheim, A

    1990-01-01

    Cancer incidence and cause-specific mortality were studied in a male cohort of 94 talc miners and 295 talc millers, exposed to non-asbestiform talc with low quartz content. No excess risk was found compared with national age-specific incidence. Six cases of lung cancer occurred versus 6.49 expected (miners: observed 2, expected 1.27; millers: observed 4, expected 5.22). There were 3 deaths due to non-malignant respiratory disease against 10.9 expected (miners: observed 1, expected 2.5; millers: observed 2, expected 8.4). Mesothelioma, tuberculosis, or pneumoconiosis were not recorded as causes of death. Pneumoconiosis was noted as a contributory cause in three cases (silicosis two, talcosis one). Further follow-up will reduce any potential impact of "healthy worker" selection.

  4. Electrostatic Characteristics of Materials Exposed to Martian Simulant Dust Particles

    NASA Astrophysics Data System (ADS)

    Calle, C. I.; Kim, H. S.; Young, S.; Jackson, D.; Lombardi, A. J.

    1998-11-01

    The Pathfinder mission to Mars identified Andesitic rock as the primary type of rock at the landing site. Several experiments were designed at NASA/Kennedy Space Center to determine the charging characteristics of common space materials exposed to small particles derived from those rocks. MARS-1, a Martian soil simulant prepared from Andesitic rocks by NASA/JSC was used in this work. Characterization of this simulant was made using scanning electron microscopy and inductively coupled argon plasma spectroscopy coupled with a carbon-sulfur detector. These results were compared to the Alpha Proton X-Ray Spectrometer analysis on Pathfinder. The simulant was found to be a suitable substitute for Martian soil for our purposes. Two experimental designs and methods to simulate the exposure of different materials to wind-blown dust were made. These designs permit dust particle delivery to samples at different speeds. Initial experiments made with these designs to determine their viability were promising.

  5. Exposed core microstructured optical fiber Bragg gratings: refractive index sensing.

    PubMed

    Warren-Smith, Stephen C; Monro, Tanya M

    2014-01-27

    Bragg gratings have been written in exposed-core microstructured optical fibers for the first time using a femtosecond laser. Second and third order gratings have been written and both show strong reflectivity at 1550 nm, with bandwidths as narrow as 60 pm. Due to the penetration of the guided field outside the fiber the Bragg reflections are sensitive to the external refractive index. As different modes have different sensitivities to refractive index but the same temperature sensitivity the sensor can provide temperature-compensated refractive index measurements. Since these Bragg gratings have been formed by physical ablation, these devices can also be used for high temperature sensing, demonstrated here up to 800°C. The fibers have been spliced to single mode fiber for improved handling and integration with commercial interrogation units.

  6. Reproductive toxicity in boron exposed workers in Bandirma, Turkey.

    PubMed

    Başaran, Nurşen; Duydu, Yalçin; Bolt, Hermann M

    2012-06-01

    Boric acid and sodium borates have been considered as being "toxic to reproduction and development", following results of animal studies with high doses. However unfavorable effects of boron exposure on reproduction and development have not been proved in epidemiological studies so far. The aim of the present study was to investigate the reproductive toxicity indicators in highly exposed workers employed in a boric acid production plant in Bandırma, Turkey. Two hundred and four workers participated in this study. The mean blood boron concentration of the high exposure group of workers was 223.89 ± 69.49 (152.82-454.02)ng/g. Unfavorable effects of boron exposure on the reproductive toxicity indicators were not observed.

  7. Acute physiological responses of squirrel monkeys exposed to hyperdynamic environments

    NASA Technical Reports Server (NTRS)

    Fuller, C. A.

    1984-01-01

    Physiological and behavioral responses to a hyperdynamic environment were examined in four adult male squirrel monkeys. After baseline monitoring at 1 G, monkeys were exposed to one of three conditions: (1) +2 Gz for 60 minutes, (2) +2.9 Gz max for 8 minutes (simulating Space Shuttle launch), or (3) +1.7 Gz max for 19 minutes (simulating Space Shuttle reentry). During all experimental conditions, heart rate rose, and colonic temperature began to decline within the first ten minutes of centrifugation and decreased by as much as 2 C in some instances. Behaviorally, during centrifugation, the monkeys seemed to exhibit drowsiness and fall asleep, an observation not made during the control period. It is concluded that primates are susceptible to acute hyperdynamic field exposure.

  8. Mechanisms of damage to corals exposed to sedimentation.

    PubMed

    Weber, Miriam; de Beer, Dirk; Lott, Christian; Polerecky, Lubos; Kohls, Katharina; Abed, Raeid M M; Ferdelman, Timothy G; Fabricius, Katharina E

    2012-06-12

    We investigated the mechanisms leading to rapid death of corals when exposed to runoff and resuspended sediments, postulating that the killing was microbially mediated. Microsensor measurements were conducted in mesocosm experiments and in naturally accumulated sediment on corals. In organic-rich, but not in organic-poor sediment, pH and oxygen started to decrease as soon as the sediment accumulated on the coral. Organic-rich sediments caused tissue degradation within 1 d, whereas organic-poor sediments had no effect after 6 d. In the harmful organic-rich sediment, hydrogen sulfide concentrations were low initially but increased progressively because of the degradation of coral mucus and dead tissue. Dark incubations of corals showed that separate exposures to darkness, anoxia, and low pH did not cause mortality within 4 d. However, the combination of anoxia and low pH led to colony death within 24 h. When hydrogen sulfide was added after 12 h of anoxia and low pH, colonies died after an additional 3 h. We suggest that sedimentation kills corals through microbial processes triggered by the organic matter in the sediments, namely respiration and presumably fermentation and desulfurylation of products from tissue degradation. First, increased microbial respiration results in reduced O(2) and pH, initiating tissue degradation. Subsequently, the hydrogen sulfide formed by bacterial decomposition of coral tissue and mucus diffuses to the neighboring tissues, accelerating the spread of colony mortality. Our data suggest that the organic enrichment of coastal sediments is a key process in the degradation of coral reefs exposed to terrestrial runoff.

  9. Arthropod succession on exposed rabbit carrion in Alexandria, Egypt.

    PubMed

    Tantawi, T I; eL-Kady, E M; Greenberg, B; el-Ghaffar, H A

    1996-07-01

    In 1988 and 1989, seasonal field studies on exposed rabbit carcasses were conducted in Alexandria, Egypt, to describe the decomposition process and arthropod succession patterns. Four decomposition stages were recognized: fresh, bloated, decay, and dry. Carcasses in summer and spring decayed at a much faster rate than those in fall and winter. The bloated stage in summer lasted longer than in spring because of the difference in breeding biology of the primary flies infesting carcasses in these seasons. Dipterous larvae of the family Calliphoridae, and to a lesser extent of the families Sarcophagidae and Muscidae, were responsible for the process of carrion degradation. Carrion-arthropod communities in cooler seasons were distinguished from those in warmer seasons by the presence of certain dipterous (muscids and fanniids) and coleopterous larvae, and by adults of small flies such as sphaerocerids and scatopsids. The presence of adult psychodids, sciarids, and phorids was unique to the winter carrion-arthropod community. Eleven species of carrion-breeding Diptera were found to coexist in the study site. The coexistence of the 2 calliphorids Chrysomya albiceps (Wiedemann) and Lucilia sericata (Meigen) in carrion in fall and spring is a new record for the Palaearctic Region. In spring, 3rd instars of C. albiceps were observed preying on the pupae of their own species. Although the carcasses were of equal size and simultaneously exposed, there was considerable variation in the rate of decay among fall carcasses only, which was attributed to unknown reasons at the beginning of the experiment and to heavy rains later on. This affected oviposition and the feeding period of maggots. Approximately 100 arthropod species were recovered on carcasses throughout the study. Diptera was the predominant group, whereas Coleoptera ranked 2nd. Carcasses in cooler seasons were richer in species than in warmer seasons.

  10. Viability and Virulence of Entomopathogenic Nematodes Exposed to Ultraviolet Radiation

    PubMed Central

    Shapiro-Ilan, David I.; Hazir, Selcuk; Lete, Luis

    2015-01-01

    Entomopathogenic nematodes (EPNs) can be highly effective biocontrol agents, but their efficacy can be reduced due to exposure to environmental stress such as from ultraviolet (UV) radiation. Our objectives were to 1) compare UV tolerance among a broad array of EPN species, and 2) investigate the relationship between reduced nematode viability (after exposure to UV) and virulence. Nematodes exposed to a UV radiation (254 nm) for 10 or 20 min were assessed separately for viability (survival) and virulence to Galleria mellonella. We compared 9 different EPN species and 15 strains: Heterorhabditis bacteriophora (Baine, fl11, Oswego, and Vs strains), H. floridensis (332), H. georgiana (Kesha), H. indica (HOM1), H. megidis (UK211), Steinernema carpocapsae (All, Cxrd, DD136, and Sal strains), S. feltiae (SN), S. rarum (17C&E), and S. riobrave (355). In viability assessments, steinernematids, particularly strains of S. carpocapsae, generally exhibited superior UV tolerance compared with the heterorhabditids. However, some heterorhabditids tended to be more tolerant than others, e.g., H. megidis and H. bacteriophora (Baine) were most susceptible and H. bacteriophora (Vs) was the only heterorhabditid that did not exhibit a significant effect after 10 min of exposure. All heterorhabditids experienced reduced viability after 20 min exposure though several S. carpocapsae strains did not. In total, after 10 or 20 min exposure, the viability of seven nematode strains did not differ from their non-UV exposed controls. In virulence assays, steinernematids (particularly S. carpocapsae strains) also tended to exhibit higher UV tolerance. However, in contrast to the viability measurements, all nematodes experienced a reduction in virulence relative to their controls. Correlation analysis revealed that viability among nematode strains is not necessarily related to virulence. In conclusion, our results indicate that the impact of UV varies substantially among EPNs, and viability alone

  11. Chromosome Aberration in Human Blood Lymphocytes Exposed to Energetic Protons

    NASA Technical Reports Server (NTRS)

    Hada, M.; George, Kerry A.; Cucinotta, F. A.

    2008-01-01

    During space flight, astronauts are exposed to a space radiation consisting of high-energy protons, high charge and energy (HZE) nuclei, as well as secondary particles that are generated when the primary particles penetrate the spacecraft shielding. Secondary particles have a higher LET value than primary protons and therefore expected to have a higher relative biological effectiveness (RBE). To investigate this theory, we exposed human peripheral blood lymphocytes to protons with energies of 250 MeV, 800MeV, 2 GeV, or 2.5 GeV. LET values for these protons ranged from 0.4 to 0.2 keV/micrometer. and doses ranged from 0.2 to 3 Gy. Over this energy the probability of nuclear reaction leading to secondary radiation, and the multiplicity of reaction produces such as neutrons and mesons increases substantially. The effect of aluminum and polyethylene shielding was also assessed using the 2 GeV and 2.5GeV proton beams. After exposure lymphocytes were stimulated to divide and chromosomes were collected from cells in the first G2 and metaphase cell cycle after exposure using a chemical induced premature chromosome condensation (PCC) technique. Dose response data for chromosome damage was analyzed using the fluorescence in situ hybridization (FISH) chromosome painting technique. Selected samples were also analyzed with multicolor FISH (mFISH) and multicolor banding FISH (mBAND) techniques. Data indicates that the dose response for simple-type exchanges is similar for proton and gamma exposure, whereas protons induce higher yields of complex exchanges that are LET dependent. RBE values will be presented for each proton energy, and the effects of shielding and possible cytogenetic signatures of proton exposure will be discussed.

  12. Risk of Spontaneous Abortion among Women Exposed to Polybrominated Biphenyls

    PubMed Central

    Small, Chanley M.; Cheslack-Postava, Keely; Terrell, Metrecia; Blanck, Heidi Michels; Tolbert, Paige; Rubin, Carol; Henderson, Alden; Marcus, Michele

    2008-01-01

    Accidental contamination of livestock in Michigan in 1973 with polybrominated biphenyls (PBBs) led to the establishment of a registry of exposed individuals in 1976. At the time of enrollment, serum was collected and analyzed for PBBs and polychlorinated biphenyls, PCBs. In 1997, women aged 18 years or older and active in the registry were invited to participate in a telephone interview about their health. Using generalized estimating equations to account for correlated outcomes within the same woman, we assessed the risk of spontaneous abortion among 529 women with 1344 potentially exposed pregnancies. PBB and PCB exposure were not associated with risk of spontaneous abortion after adjusting for maternal age at conception, age at menarche, and prior infertility. Compared to pregnancies with PBB exposure below the limit of detection, those with levels above 2.9 ppb had a non-significant reduced odds of spontaneous abortion (adjusted OR=0.73; 95% CI= 0.47-1.13). Compared to pregnancies with PCB exposure below the limit of detection, those with levels above 6.5 ppb had little difference in risk (adjusted OR=0.91; 95% CI= 0.59-1.41). Maternal age at conception above 34 years was significantly associated with elevated risk of spontaneous abortion (OR=2.46; 95% CI= 1.10-5.49). The effect of prior infertility was of borderline significance (OR=1.52; 95% CI= 0.98-2.38). Older age at menarche was associated with decreased risk of spontaneous abortion (adjusted OR=0.58; 95% CI: 0.38-0.89, comparing menarche at 12-13 with menarche <12). Our results do not support an association between exposure to PBBs or PCBs and risk of spontaneous abortion. PMID:17239850

  13. Chromosome aberrations in human blood lymphocytes exposed to energetic protons

    NASA Astrophysics Data System (ADS)

    Hada, Megumi; George, Ms Kerry; Cucinotta, Francis A.

    During space flight, astronauts are exposed to space radiation consisting of high-energy protons, high charge and energy (HZE) nuclei, as well as secondary particles that are generated when the primary particles penetrate the spacecraft shielding. Secondary particles have a higher LET value than primary protons and are therefore expected to have a higher relative biological effectiveness (RBE). To investigate this theory, we exposed human peripheral blood lymphocytes to protons with energies of 250 MeV, 800MeV, 2 GeV, or 2.5 GeV. LET values for these protons ranged from 0.4 to 0.2 keV/µm. and doses ranged from 0.2 to 3 Gy. Over this energy range the probability of nuclear reaction leading to secondary radiation, and the multiplicity of reaction products such as neutrons and mesons increases substantially. The effect of aluminum and polyethylene shielding was also assessed using the 2 GeV and 2.5GeV proton beams. After exposure lymphocytes were stimulated to divide and chromosomes were collected from cells in the first G2 and metaphase cell cycle after exposure using a chemical induced premature chromosome condensation (PCC) technique. Dose response data for chromosome damage was analyzed using the fluorescence in situ hybridization (FISH) chromosome painting technique. Selected samples were also analyzed with multicolor FISH (mFISH) and multicolor banding FISH (mBAND) techniques. Data indicates that the dose response for simple-type exchanges is similar for proton and gamma exposure, whereas protons induce higher yields of complex exchanges that are energy dependent. RBE values will be presented for each proton energy, and the effects of shielding and possible cytogenetic signatures of proton exposure will be discussed.

  14. Deciphering Genome-Environment-Wide Interactions Using Exposed Subjects Only

    PubMed Central

    Zhao, Lue Ping; Fan, Wenhong; Goodman, Gary; Radich, Jerry; Martin, Paul

    2015-01-01

    The recent successes of genome-wide association studies (GWAS) have renewed interest in genome-environment-wide interaction studies (GEWIS) to discover genetic factors that modulate penetrance of environmental exposures to human diseases. Indeed, gene-environment interactions (GxE), which have not been emphasized in the GWAS era, could be a source contributing to the missing heritability, a major bottleneck limiting continuing GWAS successes. In this manuscript, we describe a design and analytic strategy to focus on GxE using only exposed subjects, dubbed as e-GEWIS. Operationally, an e-GEWIS analysis is equivalent to a GWAS analysis on exposed subjects only, and it has actually been used in some earlier GWAS without being explicitly identified as such. Through both analytics and simulations, e-GEWIS have been shown better efficiency than the usual cross-product-based analysis of GxE interaction with both cases and controls (cc-GEWIS), and they have comparable efficiency to case-only analysis of GxE (c-GEWIS), with potentially smaller sample sizes. The formalization of e-GEWIS here provides a theoretical basis to legitimize this framework for routine investigation of GxE, for more efficient GxE study designs, and for improvement of reproducibility in replicating GEWIS findings. As an illustration, we apply e-GEWIS to a lung cancer GWAS dataset to perform a GEWIS, focusing on gene and smoking interaction. The e-GEWIS analysis successfully uncovered positive genetic associations on chromosome 15 among current smokers, suggesting a gene-smoking interaction. While this signal was detected earlier, the current finding here serves as a positive control in support of this e-GEWIS strategy. PMID:25694100

  15. Dry heat exposures of surface exposed and embedded Bacillus spores

    NASA Astrophysics Data System (ADS)

    Schubert, Wayne

    Dry heat microbial reduction (DHMR) is the primary technique used to reduce the microbial load of spacecraft and component parts. Often, manufacturing procedures require heating flight hardware to high temperatures for purposes other than planetary protection DHMR. The existing specifications, however, do not allow for additional planetary protection bioburden reduction credit if the hardware is exposed without controlled relative humidity. The intent of this study was to provide adequate data on the DHMR technique to support modification of four aspects of current requirements; expansion of acceptable time and temperature combinations used for spacecraft dry heat microbial reduction processes above 125° C, determining the effect that humidity has on spore lethality as a function of temperature, understanding the lethality for spores with exceptionally high thermal resistance and to investigate the extended exposure requirement for materials that might contain embedded microorganisms. Spores from two bacterial species were tested, B. atrophaeus ATCC 9372 and B. sp. ATCC 29669, under three conditions encompassing 5 temperature points. Embedded experiments utilized a silicone rubber polymer that is commonly used on robotic spacecraft, and surface exposed experiments were performed under both ambient and vacuum-controlled humidity conditions. The results obtained support the use of DHMR protocols that extend the maximum temperature range from 125° C to 170° C, with either controlled or ambient humidity. If implemented, this will give projects bioburden reduction credit for shorter treatments at extended temperatures, and allow spacecraft to be processed in more readily available and less expensive facilities that do not have humidity control, with significant cost and schedule benefits. The study also demonstrated that the required heating time for materials presumed to have embedded bioburden is conservative.

  16. Damage assessment in CFRP laminates exposed to impact fatigue loading

    NASA Astrophysics Data System (ADS)

    Tsigkourakos, George; Silberschmidt, Vadim V.; Ashcroft, I. A.

    2011-07-01

    Demand for advanced engineering composites in the aerospace industry is increasing continuously. Lately, carbon fibre reinforced polymers (CFRPs) became one of the most important structural materials in the industry due to a combination of characteristics such as: excellent stiffness, high strength-to-weight ratio, and ease of manufacture according to application. In service, aerospace composite components and structures are exposed to various transient loads, some of which can propagate in them as cyclic impacts. A typical example is an effect of the wind gusts during flight. This type of loading is known as impact fatigue (IF); it is a repetition of low-energy impacts. Such loads can cause various types of damage in composites: fibre breaking, transverse matrix cracking, de-bonding between fibres and matrix and delamination resulting in reduction of residual stiffness and loss of functionality. Furthermore, this damage is often sub-surface, which reinforces the need for more regular inspection. The effects of IF are of major importance due its detrimental effect on the structural integrity of components that can be generated after relatively few impacts at low force levels compared to those in a standard fatigue regime. This study utilises an innovative testing system with the capability of subjecting specimens to a series of repetitive impacts. The primary subject of this paper is to assess the damaging effect of IF on the behaviour of drilled CFRP specimens, exposed to such loading. A detailed damage analysis is implemented utilising an X-ray micro computed tomography system. The main findings suggested that at early stages of life damage is governed by o degree splits along the length of the specimens resulting in a 20% reduction of stiffness. The final failure damage scenario indicated that transverse crasks in the 90 degree plies are the main reason for complete delamination which can be translated to a 50% stiffness reduction.

  17. Neurobehavioral changes in mice exposed to fast neutrons in utero.

    PubMed

    Ishida, Yuka; Ohmachi, Yasushi; Takai, Nobuhiko; Hiraoka, Takeshi; Ogiu, Toshiaki; Nishikawa, Tetsu; Nishimura, Yoshikazu; Shimada, Yoshiya

    2011-01-01

    Epidemiological studies have revealed that radiation causes brain development abnormalities in atomic bomb survivors exposed in utero. Rat and mouse studies have also shown that prenatal exposure to low-linear energy transfer radiation induces developmental brain anomalies. Because the effects of prenatal irradiation on adult behavior patterns remain largely unknown, the present study investigated the effects of neutron exposure in utero on postnatal behavior patterns in mice. [C57BL/6J × C3H/He] hybrid (B6C3F1) mice were exposed to cyclotron-derived fast neutrons with peak energy of 10 MeV (0.02-0.2 Gy) or Cs-137 gamma-rays (0.2-1.5 Gy) on embryonic day 13.5. At 5.5-8 months of age, the neurobehavior of male offspring was examined by Rota-rod treadmill and locomotor activity. The accumulation of radio-labeled drug at muscarinic acetylcholine and serotonin receptors in mice from control and neutron-irradiated groups was determined by the tracer method. Locomotor activity during the dark period increased in the 0.02 Gy neutron-irradiated group. Furthermore, at 5.5 months of age, tracer binding in vivo to the muscarinic acetylcholine increased and to the serotonin receptors decreased in the 0.02 Gy neutron-irradiated group. In conclusion, the present study reveals that a certain "low-dose window" may exist for radiation-induced changes in neurobehavior and binding to neurotransmitter receptors, because there was correlation in neurobehavior and binding to neurotransmitter receptors in the 0.02 Gy neutron-irradiated group though there was not correlation in the neutron-irradiated groups more than 0.05 Gy.

  18. 30 CFR 75.521 - Lightning arresters; ungrounded and exposed power conductors and telephone wires.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Lightning arresters; ungrounded and exposed power conductors and telephone wires. 75.521 Section 75.521 Mineral Resources MINE SAFETY AND HEALTH... telephone wires. Each ungrounded, exposed power conductor and each ungrounded, exposed telephone wire...

  19. 30 CFR 75.521 - Lightning arresters; ungrounded and exposed power conductors and telephone wires.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Lightning arresters; ungrounded and exposed power conductors and telephone wires. 75.521 Section 75.521 Mineral Resources MINE SAFETY AND HEALTH... telephone wires. Each ungrounded, exposed power conductor and each ungrounded, exposed telephone wire...

  20. 30 CFR 75.521 - Lightning arresters; ungrounded and exposed power conductors and telephone wires.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Lightning arresters; ungrounded and exposed power conductors and telephone wires. 75.521 Section 75.521 Mineral Resources MINE SAFETY AND HEALTH... telephone wires. Each ungrounded, exposed power conductor and each ungrounded, exposed telephone wire...

  1. 30 CFR 75.521 - Lightning arresters; ungrounded and exposed power conductors and telephone wires.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Lightning arresters; ungrounded and exposed power conductors and telephone wires. 75.521 Section 75.521 Mineral Resources MINE SAFETY AND HEALTH... telephone wires. Each ungrounded, exposed power conductor and each ungrounded, exposed telephone wire...

  2. 30 CFR 75.521 - Lightning arresters; ungrounded and exposed power conductors and telephone wires.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Lightning arresters; ungrounded and exposed power conductors and telephone wires. 75.521 Section 75.521 Mineral Resources MINE SAFETY AND HEALTH... telephone wires. Each ungrounded, exposed power conductor and each ungrounded, exposed telephone wire...

  3. 42 CFR 84.86 - Component parts exposed to oxygen pressures; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Component parts exposed to oxygen pressures... PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.86 Component parts exposed to oxygen pressures... component parts exposed to oxygen pressures above atmospheric pressure are safe and compatible for...

  4. 42 CFR 84.86 - Component parts exposed to oxygen pressures; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Component parts exposed to oxygen pressures... PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.86 Component parts exposed to oxygen pressures... component parts exposed to oxygen pressures above atmospheric pressure are safe and compatible for...

  5. 42 CFR 84.86 - Component parts exposed to oxygen pressures; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Component parts exposed to oxygen pressures... PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.86 Component parts exposed to oxygen pressures... component parts exposed to oxygen pressures above atmospheric pressure are safe and compatible for...

  6. 42 CFR 84.86 - Component parts exposed to oxygen pressures; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Component parts exposed to oxygen pressures... PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.86 Component parts exposed to oxygen pressures... component parts exposed to oxygen pressures above atmospheric pressure are safe and compatible for...

  7. 42 CFR 84.86 - Component parts exposed to oxygen pressures; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Component parts exposed to oxygen pressures... PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.86 Component parts exposed to oxygen pressures... component parts exposed to oxygen pressures above atmospheric pressure are safe and compatible for...

  8. Mutagenesis in bacterial spores exposed to space and simulated martian conditions: data from the EXPOSE-E spaceflight experiment PROTECT.

    PubMed

    Moeller, Ralf; Reitz, Günther; Nicholson The Protect Team, Wayne L; Horneck, Gerda

    2012-05-01

    As part of the PROTECT experiment of the EXPOSE-E mission on board the International Space Station (ISS), the mutagenic efficiency of space was studied in spores of Bacillus subtilis 168. After 1.5 years' exposure to selected parameters of outer space or simulated martian conditions, the rates of induced mutations to rifampicin resistance (Rif(R)) and sporulation deficiency (Spo(-)) were quantified. In all flight samples, both mutations, Rif(R) and Spo(-), were induced and their rates increased by several orders of magnitude. Extraterrestrial solar UV radiation (>110 nm) as well as simulated martian UV radiation (>200 nm) led to the most pronounced increase (up to nearly 4 orders of magnitude); however, mutations were also induced in flight samples shielded from insolation, which were exposed to the same conditions except solar irradiation. Nucleotide sequencing located the Rif(R) mutations in the rpoB gene encoding the β-subunit of RNA polymerase. Mutations isolated from flight and parallel mission ground reference (MGR) samples were exclusively localized to Cluster I. The 21 Rif(R) mutations isolated from the flight experiment showed all a C to T transition and were all localized to one hotspot: H482Y. In mutants isolated from the MGR, the spectrum was wider with predicted amino acid changes at residues Q469K/L/R, H482D/P/R/Y, and S487L. The data show the unique mutagenic power of space and martian surface conditions as a consequence of DNA injuries induced by solar UV radiation and space vacuum or the low pressure of Mars.

  9. Seroprevalence of leptospirosis in rural populations inhabiting areas exposed and not exposed to floods in eastern Poland.

    PubMed

    Wasiński, Bernard; Sroka, Jacek; Wójcik-Fatla, Angelina; Zając, Violetta; Cisak, Ewa; Knap, Józef P; Sawczyn, Anna; Dutkiewicz, Jacek

    2012-01-01

    Blood serum samples collected from randomly selected groups of 100 persons inhabiting rural community 'A' located in eastern Poland and exposed to floods by the Vistula river, and 98 persons inhabiting rural community 'B', also located in eastern Poland, but in the area not exposed to floods were examined by the microscopic agglutination test (MAT) for the presence of antibodies against 18 Leptospira serovars. Positive results showed 3% of serum samples collected from community 'A', while the seroprevalence in community 'B' was 9.2%, being insignificantly higher than in community 'A'. For both examined communities (n=198), a significant positive correlation was found between the prevalence and titer of seropositive response and age of examined people (r=0.145, p=0.042). No significant differences were found between the prevalence of positive reactions in males and females (p>0.05). The reactions with 10 serovars of Leptospira (Australis, Autumnalis, Hebdomadis, Hardjo, Sejroe, Zanoni, Bataviae, Bratislava, Canicola and Grippotyphosa), belonging to 3 species (L. interrogans, L. borgpetersenii, L. kirschneri), were found in the examined communities. From both communities, of 12 persons demonstrating positive results in MAT, 9 showed reaction with one serovar, 2 with two serovars and 1 with three serovars. The highest titers found during the examination did not exceeded 800. In conclusion, our results suggest that there is only a slight, if any, hazard of an leptospirosis epidemic after the flood that afflicted eastern Poland in the year 2010 and the general epidemiological situation of leptospirosis in eastern Poland. Although there does not seem to be any cause for concern, further research is needed.

  10. Loi constitutive chimioplastique pour le beton expose aux hautes temperatures

    NASA Astrophysics Data System (ADS)

    Hammoud, Rabah

    Concrete is the most widely used construction material in the world. Even though it has been used for several centuries, its behavior to high temperature remains to be understood. In the light of recent extreme events, including accidents, and arson, special attention has been focused on the performance of concrete in the fire safety assessment of buildings and tunnels. Fire represents one of the most severe conditions encountered during the life-time of a structure. Concrete exposed to high temperature can significantly jeopardize the structural integrity and load bearing capacity of the structure. Spalling of concrete remains one of the main issues to be addressed in the case of fire in buildings and tunnels. Successful modeling of this phenomenon depends not only on the accurate prediction of the temperature distribution through structural concrete but also on its mechanical response to the heating and boundaries restrains conditions and the migration of moisture and associated pore pressures. Therefore, it is necessary to develop a reliable formulation of concrete with all required information to understand its behavior during and after exposure to elevated temperature. It is also necessary to properly assess the effects of thermal degradation in order to develop predictive tools and validate design codes. Many structural problems can be adequately worthy by an elastoplastic model. The ultimate goal of this study is the development of a new constitutive model under a chemoplastic framework. To do this, an experimental program is carried out. The purpose of this program is twofold. First, it is essential to calibrate the proposed constitutive law that will be developed, and, second, for defining an inverse a problem. Usually, uniaxial and triaxial tests, conducted with confining pressure varied between 1.3 and 24 MPa and a temperature up to 700°C, allow us to identify the constitutive law parameters. This law reproduces the reduced field strength due to

  11. Transcriptional profiling of Saccharomyces cerevisiae exposed to propolis

    PubMed Central

    2012-01-01

    Background Propolis is a natural product of plant resins collected by honeybees (Apis mellifera) from various plant sources. Our previous studies indicated that propolis sensitivity is dependent on the mitochondrial function and that vacuolar acidification and autophagy are important for yeast cell death caused by propolis. Here, we extended our understanding of propolis-mediated cell death in the yeast Saccharomyces cerevisiae by applying systems biology tools to analyze the transcriptional profiling of cells exposed to propolis. Methods We have used transcriptional profiling of S. cerevisiae exposed to propolis. We validated our findings by using real-time PCR of selected genes. Systems biology tools (physical protein-protein interaction [PPPI] network) were applied to analyse the propolis-induced transcriptional bevavior, aiming to identify which pathways are modulated by propolis in S. cerevisiae and potentially influencing cell death. Results We were able to observe 1,339 genes modulated in at least one time point when compared to the reference time (propolis untreated samples) (t-test, p-value 0.01). Enrichment analysis performed by Gene Ontology (GO) Term finder tool showed enrichment for several biological categories among the genes up-regulated in the microarray hybridization such as transport and transmembrane transport and response to stress. Real-time RT-PCR analysis of selected genes showed by our microarray hybridization approach was capable of providing information about S. cerevisiae gene expression modulation with a considerably high level of confidence. Finally, a physical protein-protein (PPPI) network design and global topological analysis stressed the importance of these pathways in response of S. cerevisiae to propolis and were correlated with the transcriptional data obtained thorough the microarray analysis. Conclusions In summary, our data indicate that propolis is largely affecting several pathways in the eukaryotic cell. However, the most

  12. Decontamination of carpet exposed to Microsporum canis hairs and spores.

    PubMed

    Moriello, Karen A

    2017-04-01

    Objectives The objective of this study was to evaluate the efficacy of vacuuming and three carpet cleaning methods for the removal of Microsporum canis spores and hairs from experimentally contaminated carpets. Methods Sterile Berber carpeting was artificially contaminated with naturally infective M canis hairs and spores. Carpet swatches were vacuumed for 10 s, 30 s and 60 s, and then cultured. Three carpet cleaning methods were evaluated on area rugs experimentally contaminated with infective material: a beater brush carpet shampooing, beater brush carpet shampooing post-disinfectant application and hot water extraction. Home cleaning products labeled as having efficacy against Trichophyton species were used in addition to 1% potassium peroxymonosulfate. Carpets were cultured at 24 h, 48 h and 7 days after cleaning. Good efficacy was no detectable spores at post-cleaning culture. Results All pretreatment carpet samples were culture positive for M canis (>300 colony-forming units [cfu]/site). Vacuuming did not decontaminate carpets but did remove intact hairs. Spores were not detected by wipe samples after two washings with an upright beater brush carpet shampooer or pretreatment with a disinfectant prior to carpet shampooing. Carpets cleaned with one hot water extraction technique had a decrease from 300 cfu/site to a mean of 5.5 cfu/site at 24 and 48 h post-cleaning and 2 cfu/site at day 7. The use of disinfectants was associated with odor, even when dry, and permanent discoloration. Hot water extraction cleaning was associated with the fastest drying time and no discoloration. Conclusions and relevance Carpets exposed to M canis can be disinfected via carpet shampooing or hot water extraction cleaning. Vacuuming of carpets is recommended to remove infective hairs. For homes, exposed carpeting can be decontaminated by routine washing with a carpet shampooer (twice) or hot water extraction. Use of pretreatment with a disinfectant is recommended when a high level

  13. Engineering a robotic approach to mapping exposed volcanic fissures

    NASA Astrophysics Data System (ADS)

    Parcheta, C. E.; Parness, A.; Mitchell, K. L.

    2014-12-01

    Field geology provides a framework for advanced computer models and theoretical calculations of volcanic systems. Some field terrains, though, are poorly preserved or accessible, making documentation, quantification, and investigation impossible. Over 200 volcanologists at the 2012 Kona Chapman Conference on volcanology agreed that and important step forward in the field over the next 100 years should address the realistic size and shape of volcanic conduits. The 1969 Mauna Ulu eruption of Kīlauea provides a unique opportunity to document volcanic fissure conduits, thus, we have an ideal location to begin addressing this topic and provide data on these geometries. Exposed fissures can be mapped with robotics using machine vision. In order to test the hypothesis that fissures have irregularities with depth that will influence their fluid dynamical behavior, we must first map the fissure vents and shallow conduit to deci- or centimeter scale. We have designed, constructed, and field-tested the first version of a robotic device that will image an exposed volcanic fissure in three dimensions. The design phase included three steps: 1) create the payload harness and protective shell to prevent damage to the electronics and robot, 2) construct a circuit board to have the electronics communicate with a surface-based computer, and 3) prototype wheel shapes that can handle a variety of volcanic rock textures. The robot's mechanical parts were built using 3d printing, milling, casting and laser cutting techniques, and the electronics were assembled from off the shelf components. The testing phase took place at Mauna Ulu, Kīlauea, Hawai'i, from May 5 - 9, 2014. Many valuable design lessons were learned during the week, and the first ever 3D map from inside a volcanic fissure were successfully collected. Three vents had between 25% and 95% of their internal surfaces imaged. A fourth location, a non-eruptive crack (possibly a fault line) had two transects imaging the textures

  14. Pulmonary nodules in workers exposed to urban stressor

    SciTech Connect

    Sancini, A.; Fioravanti, M.; Ciarrocca, M.; Palermo, P.; Fiaschetti, M.; Schifano, M.P.; Tomei, G.; Tomei, F.

    2010-07-15

    By multilayer spiral low-dose computed tomography (LD-CT) of the chest this study assesses the early detection of lung lesions on a sample of 100 traffic policemen of a big Italian city professionally exposed to urban pollutants and 100 controls non-occupationally exposed to urban pollutants matched by sex, age, length of service and cigarette smoking habit. Exposure to urban pollutants in traffic policemen was characterized using the annual average concentrations of PM{sub 10}, NO{sub 2} and benzene in the period 1998-2008 measured by fixed monitoring stations located in different areas of the city. A significant and increasing number of suspicious lung nodules with diameters between 5 and 10 mm was observed: in traffic policemen (including smokers and non-smokers) vs. controls (including smokers and non-smokers); in total smokers (including traffic policemen and controls) vs. total non-smokers (traffic policemen and controls); in smoker traffic policemen vs. smoker controls and vs. non-smoker traffic policemen; in non-smoker traffic policemen vs. non-smoker controls. The RR of finding cases with at least one lung nodule with diameters between 5 and 10 mm in traffic policemen (including smokers and non-smokers) compared to controls (including smokers and non-smokers) is 1.94 (CI 1.13-3.31); in total smokers vs. non-smokers the RR is 1.96 (CI 1.20-3.19). The comparison between the interaction exposure and smoking shows an increase in smoker traffic policemen than in smoker controls (RR=2.14; CI 1.02-4.52). The RR for smoker traffic policemen was higher than in non-smoker traffic policemen (RR=2.09; CI 1.19-3.66). The results of our study show that: (1) while smoker workers have a higher risk for developing solid suspicious lung nodules, the simple routinely exposure to urban pollutants is unable to produce the same kind of increased risk; (2) the interaction of smoking and exposure to urban pollutants greatly increases the risk for the development of solid

  15. Level of DNA damage in lead-exposed workers.

    PubMed

    Olewińska, Elżbieta; Kasperczyk, Aleksandra; Kapka, Lucyna; Kozłowska, Agnieszka; Pawlas, Natalia; Dobrakowski, Michał; Birkner, Ewa; Kasperczyk, Sławomir

    2010-01-01

    Lead plays a significant role in modern industry. This metal is related to a broad range of physiological, biochemical and behavioural dysfunctions. The genotoxic effects of lead have been studied both in animals and humans in in vitro systems but results were contradictory. The aim of this study was to investigate the association between DNA damage and occupational exposure to lead in workers. The study population consisted of 62 employees of metalworks exposed to lead in the southern region of Poland. The control group consisted of 26 office workers with no history of occupational exposure to lead. The concentration of lead (PbB) and zincprotoporphyrin (ZPP) in blood samples were measured. The DNA damage was analyzed in blood lymphocytes using alkaline comet assay. The level of DNA damage was determined as the percentage of DNA in the tail, tail length and tail moment. The lead exposure indicators were significantly higher in lead exposed group: PbB about 8.5 times and ZPP 3.3 times. Also, the percentage of DNA in the tail (60.3 ± 14 vs. 37.1 ± 17.6), comet tail length (86.9 ± 15.49 vs. 73.8 ± 19.12) and TM (57.8 ± 17.82 vs. 33.2 ± 19.13) were significantly higher in the study group when compared with the controls; however, the difference between the subgroups was only 5-10%. Years of lead exposure positively correlated with all comet assay parameters (R = 0.21-0.41). Both mean and current PbB and ZPP were correlated with tail DNA % and TM (R = 0.32; R = 0.33; R = 0.24; R = 0.26 and R = 0.34; R = 0.33; R = 0.28 and R = 0.28, respectively). This study shows that occupational exposure to lead is associated with DNA damage and confirmed that comet assay is a rapid, sensitive method suitable for biomonitoring studies.

  16. Cancer mortality among electric utility workers exposed to polychlorinated biphenyls.

    PubMed Central

    Loomis, D; Browning, S R; Schenck, A P; Gregory, E; Savitz, D A

    1997-01-01

    OBJECTIVES: To assess whether excess mortality from cancer, malignant melanoma of the skin, and cancers of the brain and liver in particular, is associated with long term occupational exposure to polychlorinated biphenyls (PCBs). METHODS: An epidemiological study of mortality was conducted among 138,905 men employed for at least six months between 1950 and 1986 at five electrical power companies in the United States. Exposures were assessed by panels composed of workers, hygienists, and managers at each company, who considered tasks performed by workers in 28 job categories and estimated weekly exposures in hours for each job. Poisson regression was used to examine mortality in relation to exposure to electrical insulating fluids containing PCBs, controlling for demographic and occupational factors. RESULTS: Neither all cause nor total cancer mortality was related to cumulative exposure to PCB insulating fluids. Mortality from malignant melanoma increased with exposure; rate ratios (RRs) relative to unexposed men for melanoma were 1.23 (95% confidence interval (95% CI) 0.56 to 2.52), 1.71 (0.68 to 4.28) and 1.93 (0.52 to 7.14) for men with < 2000, > 2000-10,000, and > 10,000 hours of cumulative exposure to PCB insulating fluids, respectively, without consideration of latency. Lagging exposure by 20 years yielded RRs of 1.29 (0.76 to 2.18), 2.56 (1.09 to 5.97), and 4.81 (1.49 to 15.50) for the same exposure levels. Mortality from brain cancer was modestly increased among men with < 2000 hours (RR 1.61, 95% CI 0.86 to 3.01) and > 2000-10,000 hours exposure (RR 1.79, 95% CI 0.81 to 3.95), but there were no deaths from brain cancer among the most highly exposed men. A lag of five years yielded slightly increased RRs. Mortality from liver cancer was not associated with exposure to PCB insulating fluids. CONCLUSIONS: This study was larger and provided more detailed information on exposure than past investigations of workers exposed to PCBs. The results suggest that PCBs

  17. Reproductive effects in birds exposed to pesticides and industrial chemicals.

    PubMed Central

    Fry, D M

    1995-01-01

    Environmental contamination by agricultural chemicals and industrial waste disposal results in adverse effects on reproduction of exposed birds. The diversity of pollutants results in physiological effects at several levels, including direct effects on breeding adults as well as developmental effects on embryos. The effects on embryos include mortality or reduced hatchability, failure of chicks to thrive (wasting syndrome), and teratological effects producing skeletal abnormalities and impaired differentiation of the reproductive and nervous systems through mechanisms of hormonal mimicking of estrogens. The range of chemical effects on adult birds covers acute mortality, sublethal stress, reduced fertility, suppression of egg formation, eggshell thinning, and impaired incubation and chick rearing behaviors. The types of pollutants shown to cause reproductive effects include organochlorine pesticides and industrial pollutants, organophosphate pesticides, petroleum hydrocarbons, heavy metals, and in a fewer number of reports, herbicides, and fungicides. o,p'-DDT, polychlorinated biphenyls (PCBs), and mixtures of organochlorines have been identified as environmental estrogens affecting populations of gulls breeding in polluted "hot spots" in southern California, the Great Lakes, and Puget Sound. Estrogenic organochlorines represent an important class of toxicants to birds because differentiation of the avian reproductive system is estrogen dependent. PMID:8593865

  18. Exposing the nonlinear viscoelastic behavior of asphalt-aggregate mixes

    NASA Astrophysics Data System (ADS)

    Levenberg, Eyal; Uzan, Jacob

    2012-05-01

    In this study asphalt-aggregate mixes are treated as both viscoelastic and viscoplastic. Following a damage mechanics approach, a nonlinear viscoelastic constitutive formulation is generated from a linear formulation by replacing `applied stresses' with `effective viscoelastic stresses'. A non-dimensional scalar entity called `relative viscoelastic stiffness' is introduced; it is defined as the ratio of applied to effective viscoelastic stress and encapsulates different types of nonlinearities. The paper proposes a computational scheme for exposing these nonlinearities by uncovering, through direct analysis of any test data, changes experienced by the `relative viscoelastic stiffness'. In general terms, the method is based on simultaneous application of creep and relaxation formulations while preserving the interrelationship between the corresponding time functions. The proposed scheme is demonstrated by analyzing a uniaxial tension test and a uniaxial compression test (separately). Results are presented and discussed, unveiling and contrasting the character of viscoelastic nonlinearities in both cases. A conceptual viewpoint is offered to explain the observations, illustrating the requirements from any candidate constitutive theory.

  19. Unique pioneer microbial communities exposed to volcanic sulfur dioxide.

    PubMed

    Fujimura, Reiko; Kim, Seok-Won; Sato, Yoshinori; Oshima, Kenshiro; Hattori, Masahira; Kamijo, Takashi; Ohta, Hiroyuki

    2016-01-21

    Newly exposed volcanic substrates contain negligible amounts of organic materials. Heterotrophic organisms in newly formed ecosystems require bioavailable carbon and nitrogen that are provided from CO2 and N2 fixation by pioneer microbes. However, the knowledge of initial ecosystem developmental mechanisms, especially the association between microbial succession and environmental change, is still limited. This study reports the unique process of microbial succession in fresh basaltic ash, which was affected by long-term exposure to volcanic sulfur dioxide (SO2). Here we compared the microbial ecosystems among deposits affected by SO2 exposure at different levels. The results of metagenomic analysis suggested the importance of autotrophic iron-oxidizing bacteria, particularly those involved in CO2 and N2 fixation, in the heavily SO2 affected site. Changes in the chemical properties of the deposits after the decline of the SO2 impact led to an apparent decrease in the iron-oxidizer abundance and a possible shift in the microbial community structure. Furthermore, the community structure of the deposits that had experienced lower SO2 gas levels showed higher similarity with that of the control forest soil. Our results implied that the effect of SO2 exposure exerted a selective pressure on the pioneer community structure by changing the surrounding environment of the microbes.

  20. Loss of gas from echogenic liposomes exposed to pulsed ultrasound

    NASA Astrophysics Data System (ADS)

    Raymond, Jason L.; Luan, Ying; Peng, Tao; Huang, Shao-Ling; McPherson, David D.; Versluis, Michel; de Jong, Nico; Holland, Christy K.

    2016-12-01

    The destruction of echogenic liposomes (ELIP) in response to pulsed ultrasound excitations has been studied acoustically previously. However, the mechanism underlying the loss of echogenicity due to cavitation nucleated by ELIP has not been fully clarified. In this study, an ultra-high speed imaging approach was employed to observe the destruction phenomena of single ELIP exposed to ultrasound bursts at a center frequency of 6 MHz. We observed a rapid size reduction during the ultrasound excitation in 139 out of 397 (35%) ultra- high-speed recordings. The shell dilation rate, which is defined as the microbubble wall velocity divided by the instantaneous radius, \\dot{{R}}  /R, was extracted from the radius versus time response of each ELIP, and was found to be correlated with the deflation. Fragmentation and surface mode vibrations were also observed and are shown to depend on the applied acoustic pressure and initial radius. Results from this study can be utilized to optimize the theranostic application of ELIP, e.g. by tuning the size distribution or the excitation frequency.

  1. The effect of kinetin on wheat seedlings exposed to boron.

    PubMed

    Eser, Ahmet; Aydemir, Tülin

    2016-11-01

    The objective of this study was to examine relationship between boron (B) induced oxidative stress and antioxidant system in boron sensitive and tolerant wheat cultivars Bezostaya and Kutluk, and also to investigate whether Kinetin (KN) enhances the level of antioxidant system, relative growth, concentration of hydrogen peroxide (H2O2), malondialdehyde (MDA) and proline and chlorophyll content in both cultivars exposed to B stress. B treatments diminished growth and chlorophyll content whereas, it enhanced accumulation of H2O2, MDA and proline, and various antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), guaiacol peroxidase (GPX) and lipoxygenase (LOX) in the shoot and root of both cultivars. However, the follow-up application of KN to the B stressed plants improved growth and chlorophyll content and further enhanced the mentioned antioxidant enzymes and level of H2O2, MDA and proline. This study thus suggests that KN improves B tolerance of the studied cultivars grown under B toxicity.

  2. Chromium distribution in an Amazonian river exposed to tannery effluent.

    PubMed

    de Sousa, Eduardo Araujo; Luz, Cleber Calado; de Carvalho, Dario Pires; Dorea, Caetano Chang; de Holanda, Igor Bruno Barbosa; Manzatto, Ângelo Gilberto; Bastos, Wanderley Rodrigues

    2016-11-01

    This study aims to evaluate the Cr concentrations in surface water, suspended particles, and bottom sediments exposed to tannery effluent releases in the Candeias River. Cr concentrations were compared in relation to environmental thresholds imposed by United States Environmental Protection Agency (USEPA) and the Brazilian Environmental Council (CONAMA), and the geoaccumulation index (Igeo) was calculated in bottom sediment. Samples were collected in flood and dry seasons. Cr extraction was done by an acid extraction and quantified by flame atomic absorption spectrometry. Most samples were found to be below the environmental thresholds imposed by CONAMA and USEPA, except in the one from the discharge zone sampled during the dry season, showing values 1.5 and 6.1 higher than CONAMA in water and bottom sediment, respectively. Cr concentrations were significantly higher (P < 0.001) in suspended particles during dry season than flood season. Surface water and bottom sediment did not show significant differences between the seasons. The Igeo revealed an enrichment of Cr in bottom sediments after discharge zone, indicating that the effluent may be contributing to metal accumulation in the sediment. Apparently, the Candeias River shows a wash behavior on the river bottom, leaching the accumulated metal deposited on the riverbed to other areas during the flood pulses, which decreases Cr concentration in the discharge zone during dry seasons. Thus, this behavior can promote Cr dispersion to unpolluted areas.

  3. Immunological studies on mice exposed subacutely to methyl isocyanate

    SciTech Connect

    Tucker, A.N.; Bucher, J.R.; Germolec, D.R.; Silver, M.T.; Vore, S.J.; Luster, M.I.

    1987-06-01

    The immunotoxicity of methyl isocyanate (MIC) was evaluated in female B6C3F1 mice exposed via inhalation to 0, 1, or 3 ppm for 6 hr per day on 4 consecutive days. The antibody response to sheep erythrocytes and natural killer cell activity were found to be unaffected by MIC exposure. Although lymphoproliferative responses to mitogens were moderately suppressed by MIC, the differences were not statistically significant. The response of splenic lymphocytes to allogeneic leukocytes in a mixed leukocyte response (MLR) was suppressed in a dose-related fashion and was significantly different from the control response at the 3 ppm level. This effect was thought to be secondary and a result of general toxicity rather than a direct effect of MIC on the immune system. Furthermore, resistance to the infectious agents Listeria monocytogenes, mouse malaria parasite, and influenza virus, or to transplantable tumor cells was not compromised by MIC exposure. Thus, the immune system does not appear to be a primary target for MIC toxicity.

  4. Medical monitoring of asbestos-exposed workers: experience from Poland.

    PubMed

    Świątkowska, Beata; Szeszenia-Dąbrowska, Neonila; Wilczyńska, Urszula

    2016-08-01

    In Poland, the use of asbestos was banned in 1997 and asbestos plants have been closed since then. Despite their closure, cases of asbestos-related occupational diseases among former asbestos workers are still being recorded in the Central Register of Occupational Diseases. Between 2001 and 2014, there were 2726 asbestos-related illnesses, classified and reported as diseases associated with occupational exposure to asbestos. In 2000, Poland introduced a programme called Amiantus, targeted at former asbestos-processing plant workers. The programme provided periodic medical examinations to workers and free access to medications for treatment of asbestos-related illnesses. Introduction of the programme provided additional data to generate a reliable estimation of the number of asbestos-related occupational diseases, including cancer. The average latency period for asbestosis, lung cancer and mesothelioma is about 40 years so there may still be some health impact to former workers necessitating follow-up. We present the Polish experience of implementing a medical examination programme for asbestos-exposed workers and provide a list of activities to consider when planning for such a programme.

  5. Morphometric Evaluation of Pulmonary Lesions in Rats Exposed to Ozone

    PubMed Central

    Plopper, C. G.; Dungworth, D. L.; Tyler, W. S.

    1973-01-01

    Four hours exposure to 3 ppm ozone produces morphometrically quantifiable alterations in the lungs of rats. Lungs of exposed rats were fixed either immediately after exposure or after a 12-hour recovery period, and the tissue was evaluated using stereologic technics with both the light and electron microscopes. Immediately after exposure, the volume fraction of nonparenchymal tissue was larger (0.057) than for controls (0.045); that of the lumina of large vessels decreased (0.039) from the control value (0.059). The nonparenchymal tissue fraction was 0.053 12 hours later, while the luminal fraction (0.054) resembled the control value. The volume fractions of parenchyma, total tissue and air space showed only slight changes. Ozone also affects all three components of the air-blood barrier, primarily by the production of intracellular edema. The arithmetic mean thickness of the pulmonary blood-air barrier increased from 1.385 ± 0.095 μ in unexposed rats to 1.700 ± 0.189 μ in rats immediately after exposure. The primary increase was in thickness of membranous epithelial and capillary endothelial cells. Partial recovery of total barrier thickness (1.582 ± 0.292 μ) occurred 12 hours after exposure. ImagesFig 1Fig 2Fig 3Fig 4Fig 5 PMID:4577265

  6. The efficiency of photovoltaic cells exposed to pulsed laser light

    NASA Technical Reports Server (NTRS)

    Lowe, R. A.; Landis, G. A.; Jenkins, P.

    1993-01-01

    Future space missions may use laser power beaming systems with a free electron laser (FEL) to transmit light to a photovoltaic array receiver. To investigate the efficiency of solar cells with pulsed laser light, several types of GaAs, Si, CuInSe2, and GaSb cells were tested with the simulated pulse format of the induction and radio frequency (RF) FEL. The induction pulse format was simulated with an 800-watt average power copper vapor laser and the RF format with a frequency-doubled mode-locked Nd:YAG laser. Averaged current vs bias voltage measurements for each cell were taken at various optical power levels and the efficiency measured at the maximum power point. Experimental results show that the conversion efficiency for the cells tested is highly dependent on cell minority carrier lifetime, the width and frequency of the pulses, load impedance, and the average incident power. Three main effects were found to decrease the efficiency of solar cells exposed to simulated FEL illumination: cell series resistance, LC 'ringing', and output inductance. Improvements in efficiency were achieved by modifying the frequency response of the cell to match the spectral energy content of the laser pulse with external passive components.

  7. Cancer occurrence in shipyard workers exposed to asbestos in Hawaii.

    PubMed

    Kolonel, L N; Yoshizawa, C N; Hirohata, T; Myers, B C

    1985-08-01

    Because large numbers of persons were employed in United States shipyards during World War II, the long-term risks for cancer associated with asbestos exposure in this setting are of great concern. We report here on the mortality findings after up to 29 years of follow-up on a retrospective cohort of 7971 male Pearl Harbor Naval Shipyard workers, which included more than 3000 men whose employment period spanned the World War II years. Compared with the general population of Hawaii, workers in the shipyard cohort had no increase in total mortality or in total cancer mortality irrespective of the duration of their exposure. However, the risk ratio for lung cancer among workers with at least 15 years of asbestos exposure was 1.4 overall (95% confidence interval, 1.0 to 2.0) and 1.7 for those with a latency interval of 30 or more years (95% confidence interval, 1.0 to 2.5). In addition, seven mesotheliomas occurred between 1977 and 1982 in a subset of the cohort, consisting of 7029 Hawaii residents who are being followed prospectively for cancer incidence. This represented an incidence of 67.3 per million men per year, compared with a rate of 5.8 for the state as a whole. These results suggest that the long-term relative increase in risk for mesothelioma may be even greater than that for bronchogenic carcinoma in this and other cohorts of United States shipyard workers exposed to asbestos.

  8. Exposing Middle School Students to Remote Sensing in Alaska

    NASA Astrophysics Data System (ADS)

    Prakash, A.

    2003-12-01

    The need for attracting young minds to scientific research at an early stage is already recognized. Efforts are underway by major organizations to inspire the next generation of scientists. To be effective, there is a need to exploit the potential of the World Wide Web and bring it to a status that printed media have already reached. We find series of theme oriented books for children but websites with such stories are few and scattered. NASA's efforts in generating remote sensing based web stories such as the 'Adventures of Amelia the Pigeon' and 'Echo the Bat' are very good examples and starting points for generating more theme based material for children. 'Alaska: A Bird's Eye View' is a web-based story, specifically designed for grade 5-8 students. The story that is told by a Canada Goose exposes children to the truths of the remote State of Alaska and to the potential of satellite remote sensing. Examples on use remote sensing for monitoring volcanoes and sea ice edge dynamics are related to children in simple and effective ways. The topic of global climate change and its effect on marine animals has also been introduced to children.

  9. Preventing alcohol-exposed pregnancy among American-Indian youth.

    PubMed

    Jensen, Jamie; Baete Kenyon, Den Yelle; Hanson, Jessica D

    Research has determined that the prevention of alcohol-exposed pregnancies (AEP) must occur pre-conceptually with women, either by reducing alcohol intake in women planning pregnancy or at-risk for becoming pregnant, or by preventing pregnancy in women drinking at risky levels. One such AEP prevention programme with non-pregnant American Indian women is the Oglala Sioux Tribe (OST) CHOICES (Changing High-risk alcohOl use and Increasing Contraception Effectiveness Study) Programme, which shows promise in reducing AEP risk in American Indian women aged 18 or older. A community needs assessment was conducted with key informant interviews and focus groups with an emphasis on how to expand OST CHOICES. To identify interconnected themes, a content analysis methodology was used on the qualitative feedback from the focus groups and interviews. Altogether, key informant interviews were completed with 25 health and social service professionals. Eight focus groups were held with 58 American Indian participants, including adult women of child-bearing age, elder women, and adult men. Several sub-themes regarding the prevention of AEP with youth were identified, expanding the OST CHOICES curriculum into the schools, and the role of family and culture within AEP prevention.

  10. Toxicogenomic profiling of chemically exposed humans in risk assessment

    PubMed Central

    McHale, Cliona M.; Zhang, Luoping; Hubbard, Alan E.; Smith, Martyn T.

    2010-01-01

    Gene-environment interactions contribute to complex disease development. The environmental contribution, in particular low-level and prevalent environmental exposures, may constitute much of the risk and contribute substantially to disease. Systematic risk evaluation of the majority of human chemical exposures, has not been conducted and is a goal of regulatory agencies in the U.S. and worldwide. With the recent recognition that toxicological approaches more predictive of effects in humans are required for risk assessment, in vitro human cell line data as well as animal data are being used to identify toxicity mechanisms that can be translated into biomarkers relevant to human exposure studies. In this review, we discuss how data from toxicogenomic studies of exposed human populations can inform risk assessment, by generating biomarkers of exposure, early effect, and/or susceptibility, elucidating mechanisms of action underlying exposure-related disease, and detecting response at low doses. Good experimental design incorporating precise, individual exposure measurements, phenotypic anchors (pre-disease or traditional toxicological markers), and a range of relevant exposure levels, is necessary. Further, toxicogenomic studies need to be designed with sufficient power to detect true effects of the exposure. As more studies are performed and incorporated into databases such as the Comparative Toxicogenomics Database (CTD) and Chemical Effects in Biological Systems (CEBS), data can be mined for classification of newly tested chemicals (hazard identification), and, for investigating the dose-response, inter-relationship among, genes, environment and disease in a systems biology approach (risk characterization). PMID:20382258

  11. Thyroid function in Yusho patients exposed to polychlorinated biphenyls (PCB)

    SciTech Connect

    Murai, K.; Okamura, K.; Tsuji, H.; Kajiwara, E.; Watanabe, H.; Akagi, K.; Fujishima, M.

    1987-12-01

    Thyroid function was investigated in 123 Yusho patients who were exposed to toxic levels of polychlorinated biphenyls (PCBs) 16 years ago. In Yusho patients, compared with the patients without evidence of Yusho or normal controls, the serum triiodothyronine (T/sub 3/) and thyroxine (T/sub 4/) levels were significantly higher, while thyroid stimulating hormone (TSH) levels measured by sensitive assay were normal. There was no difference in serum levels of albumin, alkaline phosphatase, total cholesterol, and thyroxine binding globulin (TBG) between the two groups and the prevalence of positive antithyroid autoantibodies was almost the same, suggesting that hyperthyroxinemia in Yusho patients was not due to increased TBG binding or abnormal autoimmune mechanism. Serum free T/sub 4/ levels, however, were not elevated, although T/sub 4//TBG ratio was significantly higher. The thyroid hormone levels were higher than normal value in 4 of 123 Yusho patients but only 1 case had clinical symptoms such as excessive perspiration. Despite higher serum PCBs in Yusho patients, there was no correlation between PCB levels and levels of T/sub 3/, T/sub 4/, or TSH. The present results suggest hyperthyroxinemia without obvious clinical symptoms in Yusho patients long after exposure to PCBs.

  12. Risk of Hepatocellular Carcinoma in Workers Exposed to Chemicals

    PubMed Central

    Uccello, Mario; Malaguarnera, Giulia; Corriere, Thea; Biondi, Antonio; Basile, Francesco; Malaguarnera, Mariano

    2012-01-01

    Context Studies on experimental animals have shown liver is a common target of chemical carcinogens; this might suggest that occupational exposure to chemicals is another risk factor for HCC. However, the relationship between occupation and liver cancer has not been extensively studied, with the exception of the known association between vinyl chloride and angiosarcoma of the liver. Evidence Acquisition A MEDLINE and conventional search of the past 50 years of the medical literature was performed to identify relevant articles on incidence and mechanisms of HCC due to occupational exposure to chemicals. Several important edited books and monographs were also identified and reviewed. Results While laboratory data clearly indicate that the liver is an important target of chemical carcinogenesis, epidemiological studies provide very limited evidence on occupational risk factors for HCC. Nevertheless, we found some case reports and epidemiological data showing a moderately increased risk of HCC development in people exposed to vinyl chloride, organic solvents, pesticides, polychlorinated biphenyls, and arsenic. Conclusions Occupational exposure to chemicals may be another risk factor for HCC development, but the interpretation of currently available findings is limited by the small number of studies, questionable accuracy of the diagnosis of liver cancer, and potential confounding or modifying factors such as chronic hepatitis virus infection and alcohol consumption. Further relevant investigations are required for clarifying the actual contribution of occupational exposure to chemicals in HCC development. PMID:23162599

  13. Donation to disaster relief campaigns: underlying social cognitive factors exposed.

    PubMed

    Oosterhof, Liesbeth; Heuvelman, Ard; Peters, Oscar

    2009-05-01

    A number of very serious natural disasters have put an enormous pressure on relief organizations in the last few years. The present study exposes underlying social cognitive factors for donation to relief campaigns. A causal model was constructed, based on social cognitive theory, research on attitudes, and the impact of media exposure. The aim was to expand and improve an already existing model by Cheung and Chan [Cheung, C. K., & Chan, C. M. (2000). Social-cognitive factors of donating money to charity, with special attention to an international relief organisation. Evaluation and Program Planning, 23, 241-253]. The expanded model showed a better fit. Furthermore, the expanded model explained two-thirds of the variance of the intention to donate to a disaster relief campaign. The greatest predictor of the intention to donate proved to be "Past donation to disaster relief campaigns." The factor "News exposure" was indicated to be a valuable additional factor, as it had a significant direct effect on "Awareness of a disaster relief campaign" and was the only factor that had a total effect on all other factors, including "Intention to donate to a disaster relief campaign."

  14. Melatonin protects uterus and oviduct exposed to nicotine in mice

    PubMed Central

    Saadat, Seyedeh Nazanin Seyed; Jahromi, Sina Khajeh; Homafar, Mohammad Amin; Haghiri, Mostafa

    2014-01-01

    Smoking is associated with higher infertility risk. The aim of this study was to evaluate protective effects of melatonin on the uterus and oviduct in mice exposed to nicotine. Adult female mice (n=32) were divided into four groups. Group A: control animals received normal saline, Group B: injected with nicotine 40µg/kg, Group C: injected with melatonin 10 µg, Group D: injected with nicotine 40µg/kg and melatonin 10 µg. All animals were treated over 15 days intraperitoneally. On the 16th day, animals in the estrus phase were dissected and their uterus and oviducts were removed. Immunohistochemistry was recruited for studying apoptosis and for detection of estrogen receptor (ER) alpha in luminal epithelium of the uterus and oviduct. Enzyme-linked immunosorbent assay was used for serum estradiol level determination. Nicotine in group B decreased estradiol level and ERalpha numbers both in the uterus and oviduct (p<0.05). Co-administration of melatonin-nicotine in Group D ameliorated the histology of the uterus and oviduct, increased ERalpha numbers and reduced apoptosis in the uterus and oviduct compared with the nicotine Group B (p<0.05). This study indicates that nicotine impairs the histology of the uterus and oviduct and co-administration of melatonin-nicotine ameliorates these findings, partly through alteration in ERalpha numbers and reduction of apoptosis. PMID:26038675

  15. Nimesulide: patients still exposed to a risk of severe hepatitis.

    PubMed

    2011-05-01

    Nimesulide, a nonsteroidal antiinflammatory drug (NSAID) that has been marketed in France since 1998, is neither more effective nor better tolerated than other NSAIDs. Many reports and reviews published by drug regulatory agencies in Spain, Ireland and Italy have warned of the hepatic adverse effects of nimesulide. In early 2008, 17 cases of nimesulide-induced liver damage requiring transplantation had been reported in Ireland, Italy, Spain, Finland and France. An Italian retrospective study conducted between 1997 and 2001, including about 400 000 patients exposed to NSAIDs, showed that the risk of severe liver damage was twice as high with nimesulide as with other NSAIDs. The European pharmacovigilance database shows that nimesulide is associated with more cases of severe liver damage than other NSAIDs, as well as more cases of liver damage than with cox-2 inhibitors. Young women are particularly at risk. In the vast majority of cases of liver damage, the dose of nimesulide used was that recommended in the summary of product characteristics (SPC). Liver damage occurred within 15 days after taking the first dose of nimesulide in one-third of cases. It is unacceptable that nimesulide still remains on the market in France and other countries: reports of severe liver damage continue to accumulate, and many other therapeutic options are available.

  16. Toward Exposing Timing-Based Probing Attacks in Web Applications.

    PubMed

    Mao, Jian; Chen, Yue; Shi, Futian; Jia, Yaoqi; Liang, Zhenkai

    2017-02-25

    Web applications have become the foundation of many types of systems, ranging from cloud services to Internet of Things (IoT) systems. Due to the large amount of sensitive data processed by web applications, user privacy emerges as a major concern in web security. Existing protection mechanisms in modern browsers, e.g., the same origin policy, prevent the users' browsing information on one website from being directly accessed by another website. However, web applications executed in the same browser share the same runtime environment. Such shared states provide side channels for malicious websites to indirectly figure out the information of other origins. Timing is a classic side channel and the root cause of many recent attacks, which rely on the variations in the time taken by the systems to process different inputs. In this paper, we propose an approach to expose the timing-based probing attacks in web applications. It monitors the browser behaviors and identifies anomalous timing behaviors to detect browser probing attacks. We have prototyped our system in the Google Chrome browser and evaluated the effectiveness of our approach by using known probing techniques. We have applied our approach on a large number of top Alexa sites and reported the suspicious behavior patterns with corresponding analysis results. Our theoretical analysis illustrates that the effectiveness of the timing-based probing attacks is dramatically limited by our approach.

  17. Pharmaceuticals Exposed to the Space Environment: Problems and Prospects

    NASA Technical Reports Server (NTRS)

    Jaworske, Donald A.; Myers, Jerry G.

    2016-01-01

    The NASA Human Research Program (HRP) Health Countermeasures Element maintains ongoing efforts to inform detailed risks, gaps, and further questions associated with the use of pharmaceuticals in space. Most recently, the Pharmacology Risk Report, released in 2010, illustrates the problems associated with maintaining pharmaceutical efficacy. Since the report, one key publication includes evaluation of pharmaceutical products stored on the International Space Station (ISS). This study shows that selected pharmaceuticals on ISS have a shorter shelf-life in space than corresponding terrestrial controls. The HRP Human Research Roadmap for planetary exploration identifies the risk of ineffective or toxic medications due to long-term storage during missions to Mars. The roadmap also identifies the need to understand and predict how pharmaceuticals will behave when exposed to radiation for long durations. Terrestrial studies of returned samples offer a start for predictive modeling. This paper shows that pharmaceuticals returned to Earth for post-flight analyses are amenable to a Weibull distribution analysis in order to support probabilistic risk assessment modeling. The paper also considers the prospect of passive payloads of key pharmaceuticals on sample return missions outside of Earth's magnetic field to gather additional statistics. Ongoing work in radiation chemistry suggests possible mitigation strategies where future work could be done at cryogenic temperatures to explore methods for preserving the strength of pharmaceuticals in the space radiation environment, perhaps one day leading to an architecture where pharmaceuticals are cached on the Martian surface and preserved cryogenically.

  18. Transcriptomic and proteomic profiling of maize embryos exposed to camptothecin

    PubMed Central

    2011-01-01

    Background Camptothecin is a plant alkaloid that specifically binds topoisomerase I, inhibiting its activity and inducing double stranded breaks in DNA, activating the cell responses to DNA damage and, in response to severe treatments, triggering cell death. Results Comparative transcriptomic and proteomic analyses of maize embryos that had been exposed to camptothecin were conducted. Under the conditions used in this study, camptothecin did not induce extensive degradation in the genomic DNA but induced the transcription of genes involved in DNA repair and repressed genes involved in cell division. Camptothecin also affected the accumulation of several proteins involved in the stress response and induced the activity of certain calcium-dependent nucleases. We also detected changes in the expression and accumulation of different genes and proteins involved in post-translational regulatory processes. Conclusions This study identified several genes and proteins that participate in DNA damage responses in plants. Some of them may be involved in general responses to stress, but others are candidate genes for specific involvement in DNA repair. Our results open a number of new avenues for researching and improving plant resistance to DNA injury. PMID:21595924

  19. Unique pioneer microbial communities exposed to volcanic sulfur dioxide

    PubMed Central

    Fujimura, Reiko; Kim, Seok-Won; Sato, Yoshinori; Oshima, Kenshiro; Hattori, Masahira; Kamijo, Takashi; Ohta, Hiroyuki

    2016-01-01

    Newly exposed volcanic substrates contain negligible amounts of organic materials. Heterotrophic organisms in newly formed ecosystems require bioavailable carbon and nitrogen that are provided from CO2 and N2 fixation by pioneer microbes. However, the knowledge of initial ecosystem developmental mechanisms, especially the association between microbial succession and environmental change, is still limited. This study reports the unique process of microbial succession in fresh basaltic ash, which was affected by long-term exposure to volcanic sulfur dioxide (SO2). Here we compared the microbial ecosystems among deposits affected by SO2 exposure at different levels. The results of metagenomic analysis suggested the importance of autotrophic iron-oxidizing bacteria, particularly those involved in CO2 and N2 fixation, in the heavily SO2 affected site. Changes in the chemical properties of the deposits after the decline of the SO2 impact led to an apparent decrease in the iron-oxidizer abundance and a possible shift in the microbial community structure. Furthermore, the community structure of the deposits that had experienced lower SO2 gas levels showed higher similarity with that of the control forest soil. Our results implied that the effect of SO2 exposure exerted a selective pressure on the pioneer community structure by changing the surrounding environment of the microbes. PMID:26791101

  20. Discrimination of poorly exposed lithologies in AVIRIS data

    NASA Technical Reports Server (NTRS)

    Farrand, William H.; Harsanyi, Joseph C.

    1993-01-01

    One of the advantages afforded by imaging spectrometers such as AVIRIS is the capability to detect target materials at a sub-pixel scale. This paper presents several examples of the identification of poorly exposed geologic materials - materials which are either subpixel in scale or which, while having some surface expression over several pixels, are partially covered by vegetation or other materials. Sabol et al. (1992) noted that a primary factor in the ability to distinguish sub-pixel targets is the spectral contrast between the target and its surroundings. In most cases, this contrast is best expressed as an absorption feature or features present in the target but absent in the surroundings. Under such circumstances, techniques such as band depth mapping (Clark et al., 1992) are feasible. However, the only difference between a target material and its surroundings is often expressed solely in the continuum. We define the 'continuum' as the reflectance or radiance spanning spectral space between spectral features. Differences in continuum slope and shape can only be determined by reduction techniques which considers the entire spectral range; i.e., techniques such as spectral mixture analysis (Adams et al., 1989) and recently developed techniques which utilize an orthogonal subspace projection operator (Harsanyi, 1993). Two of the three examples considered herein deal with cases where the target material differs from its surroundings only by such a subtle continuum change.

  1. Environmental and biological monitoring of workers exposed to inorganic lead.

    PubMed

    De Medinilla, J; Espigares, M

    1991-01-01

    A total of 20 workers who were exposed to inorganic lead in two local firms (M and N) were studied. Lead concentrations in the air (PbA) at firm M exceeded the threshold limit value (TLV) of 0.150 mg/m3 established by Spanish and EC legislation, while atmospheric lead at firm N exceeded the action level of 0.075 mg/m3. In the same population, biological exposure indices (BEI) were also determined; these included lead in whole blood (PbB), erythrocyte activity of aminolevulinic acid (ALA-D), urinary excretion of aminolevulinic acid (ALA-U) and zinc protoporphyrin (ZPP). The relationship between the exposure parameters (PbA, PbB) and the biological activity indices (ALA-D, ALA-U, ZPP) were analysed statistically in order to obtain levels of significance, coefficients of correlation and regression equations. The high coefficients of correlation found confirm the usefulness of BEI in evaluating exposure to lead fumes and lead dust.

  2. Atmospheric deposition exposes Qinling pandas to toxic pollutants.

    PubMed

    Chen, Yi-Ping; Zheng, Ying-Juan; Liu, Qiang; Song, Yi; An, Zhi-Sheng; Ma, Qing-Yi; Ellison, Aaron M

    2016-12-31

    The giant panda (Ailuropoda melanoleuca) is one of the most endangered animals in the world, and it is recognized worldwide as a symbol for conservation. A previous study showed that wild and captive pandas, especially those of the Qinling subspecies, were exposed to toxicants in their diet of bamboo; the ultimate origin of these toxicants is unknown. Here we show that atmospheric deposition is the most likely origin of heavy metals and persistent organic pollutants (POPs) in the diets of captive and wild Qinling pandas. Average atmospheric deposition was 199, 115 and 49 g∙m(-2) ∙yr(-1) in the center of Xi'an city, at China's Shaanxi Wild Animal Research Center (SWARC), and at Foping National Nature Reserve (FNNR), respectively. Atmospheric deposition of heavy metals (As, Cd, Cr, Pb, Hg, Co, Cu, Zn, Mn and Ni) and POPs was highest at Xi'an city, intermediate at SWARC, and lowest at FNNR. Soil concentrations of the aforementioned heavy metals other than As and Zn also were significantly higher at SWARC than at FNNR. Efforts to conserve Qinling pandas may be compromised by air pollution attendant to China's economic development. Improvement of air quality and reductions of toxic emissions are urgently required to protect China's iconic species. This article is protected by copyright. All rights reserved.

  3. Temperature and adrenocortical responses in rhesus monkeys exposed to microwaves

    SciTech Connect

    Lotz, W.G.; Podgorski, R.P.

    1982-12-01

    To determine if the endocrine response to microwave exposure was similar in a primate to that reported for other animals, rectal temperature and plasma levels of cortisol, thyroxine (T4), and growth hormone (GH) were measured in rhesus monkeys exposed to 1.29-GHz microwave radiation. Exposures were carried out under far-field conditions with the monkey restrained in a chair. Incident power densities of 0, 20, 28, and 38 mW/sq cm were used, with corresponding specific absorption rates of 0, 2.1, 3.0, and 4.1 W/kg. Blood samples were taken hourly via an indwelling jugular venous catheter over a 24-h period before, during, and after an 8-h exposure. Rectal temperature increased an average of 0.5, 0.7, and 1.7 C for the three intensities used. No changes in T4 or GH were observed. Cortisol levels were increased during exposure to 38 mW/sq cm. It was concluded that the temperature and adrenocortical responses to microwave exposure of the rhesus monkey are similar to the corresponding responses of other animals.

  4. Coating concrete secondary containment structures exposed to agrichemicals

    SciTech Connect

    Broder, M.F.; Nguyen, D.T.

    1995-06-01

    Concrete has traditionally been the material of choice for building secondary containment structures because it is relatively inexpensive and has structural properties which make it ideal for supporting the loads of vehicles and large tanks. However, concrete`s chemical properties make it susceptible to corrosion by some common fertilizers. Though fairly impervious to water movement, concrete is easily penetrated by vapors and solvents. It is also prone to cracking. For these reasons, the Environmental Protection Agency (EPA) believes that concrete alone may not provide an effective barrier to pesticide movement and has proposed that concrete in pesticide secondary containment structures be sealed or coated to reduce its permeability. Some state secondary containment regulations require that concrete exposed to fertilizers and pesticides be sealed or protected with a coating. Lacking guidelines, some retailers have used penetrating sealants to satisfy the law, even though these products provide little protection from chemical attack nor do they prevent pesticide egress. Other retailers who have applied thick film coatings which were properly selected have had disastrous results because the application was poorly done. Consequently, much skepticism exists regarding the performance and benefit of protective coatings.

  5. Lubricant retention for liquid infused surfaces exposed to turbulent flow

    NASA Astrophysics Data System (ADS)

    Fu, Matthew; Hultmark, Marcus

    2015-11-01

    Liquid infused surfaces have been proposed as a robust alternative to traditional, air-filled superhydrophobic surfaces. The mobility of the liquid lubricant facilitates a surface slip with the outer turbulent shear flow. However, shear driven drainage in turbulent flow has been found to be a primary failure mechanism for such surfaces, resulting in loss of lubricant and the associated slip effect. A turbulent channel flow facility is used to characterize shear-driven drainage behavior of liquid infused micro-patterned surfaces. Micro-manufactured surfaces can be mounted flush in the channel and exposed to turbulent flows. The retention of fluorescent lubricants is monitored to characterize how surface geometry and lubricant properties affect the steady state retention length. Results are compared with theoretical predictions and experiments for lubricant retention in laminar microchannels, where the shear driven drainage is balanced by a Laplace pressure gradient, to determine the additional drainage induced by turbulent fluctuations. Supported under ONR Grants N00014-12-1-0875 and N00014-12-1-0962 (program manager Ki-Han Kim).

  6. OPC Paste Samples Exposed To Aggressive Solutions. Cementitious Barriers Partnership

    SciTech Connect

    Langton, C.

    2014-11-01

    The study presented in this report focused on a low-activity wasteform containing a high-pH pore solution with a significant level of sulfate. The purpose of the study was to improve understanding of the complex concrete/wasteform reactive transport problem, in particular, the role of pH in sulfate attack. Paste samples prepared at three different water-to-cement ratios were tested. The mixtures were prepared with ASTM Type I cement, without additional admixtures. The samples were exposed to two different sodium sulfate contact solutions. The first solution was prepared at 0.15M Na2SO4. The second solution also incorporated 0.5M NaOH, to mimic the high pH conditions found in Saltstone. The data collected indicated that, in Na2SO4 solution, damage occurs to the pastes. In the case of the high-pH sulfate solution (Na2SO4 + NaOH), no signs of damage were observed on any of the paste mixtures. These results indicate that the high sulfate content found in the wasteform pore solution will not necessarily lead to severe damage to concrete. Good-quality mixtures could thus prove durable over the long term, and act as an effective barrier to prevent radionuclides from reaching the environment.

  7. Heterogeneous ice nucleation of mineral dust particles exposed to ozone

    NASA Astrophysics Data System (ADS)

    Kanji, Zamin A.; Welti, André; Chou, Cédric; Stetzer, Olaf; Lohmann, Ulrike

    2013-05-01

    Deposition and immersion mode ice nucleation studies of kaolinite (Ka) and Arizona Test Dust (ATD) particles exposed to ozone at 430 ppbv, 1.4 and 4.3 ppmv for approximately 2 hours in a stainless steel aerosol tank are presented. The polydisperse particles used have a mode mobility diameter of 800 nm for Ka and 400 nm for ATD. The portable ice nucleation chamber (PINC) and immersion chamber (IMCA-ZINC) were used to study deposition and immersion mode ice nucleation respectively. Both instruments sampled through a particle impactor with a diameter cut-off size of 1 μm. Preliminary results indicate that ice nucleation can be enhanced or inhibited depending on ozone concentration used for the ageing process with higher concentrations suppressing ice nucleation in both immersion and deposition modes. Additionally, Ka and ATD respond differently to the ageing process and to the different modes of ice nucleation. Ozone surface coverage and initial uptake coefficients are presented for the low exposure studies to explain the ice nucleation behavior observed. Ice Active Surface Site Densities (IASSD) are presented as a means of comparison and parameterization of the data to predict potential atmospheric ice nuclei (IN) concentrations.

  8. RADIOLYTIC GAS PRODUCTION RATES OF POLYMERS EXPOSED TO TRITIUM GAS

    SciTech Connect

    Clark, E.

    2013-08-31

    Data from previous reports on studies of polymers exposed to tritium gas is further analyzed to estimate rates of radiolytic gas production. Also, graphs of gas release during tritium exposure from ultrahigh molecular weight polyethylene (UHMW-PE), polytetrafluoroethylene (PTFE, a trade name is Teflon®), and Vespel® polyimide are re-plotted as moles of gas as a function of time, which is consistent with a later study of tritium effects on various formulations of the elastomer ethylene-propylene-diene monomer (EPDM). These gas production rate estimates may be useful while considering using these polymers in tritium processing systems. These rates are valid at least for the longest exposure times for each material, two years for UHMW-PE, PTFE, and Vespel®, and fourteen months for filled and unfilled EPDM. Note that the production “rate” for Vespel® is a quantity of H{sub 2} produced during a single exposure to tritium, independent of length of time. The larger production rate per unit mass for unfilled EPDM results from the lack of filler- the carbon black in filled EPDM does not produce H{sub 2} or HT. This is one aspect of how inert fillers reduce the effects of ionizing radiation on polymers.

  9. Unique pioneer microbial communities exposed to volcanic sulfur dioxide

    NASA Astrophysics Data System (ADS)

    Fujimura, Reiko; Kim, Seok-Won; Sato, Yoshinori; Oshima, Kenshiro; Hattori, Masahira; Kamijo, Takashi; Ohta, Hiroyuki

    2016-01-01

    Newly exposed volcanic substrates contain negligible amounts of organic materials. Heterotrophic organisms in newly formed ecosystems require bioavailable carbon and nitrogen that are provided from CO2 and N2 fixation by pioneer microbes. However, the knowledge of initial ecosystem developmental mechanisms, especially the association between microbial succession and environmental change, is still limited. This study reports the unique process of microbial succession in fresh basaltic ash, which was affected by long-term exposure to volcanic sulfur dioxide (SO2). Here we compared the microbial ecosystems among deposits affected by SO2 exposure at different levels. The results of metagenomic analysis suggested the importance of autotrophic iron-oxidizing bacteria, particularly those involved in CO2 and N2 fixation, in the heavily SO2 affected site. Changes in the chemical properties of the deposits after the decline of the SO2 impact led to an apparent decrease in the iron-oxidizer abundance and a possible shift in the microbial community structure. Furthermore, the community structure of the deposits that had experienced lower SO2 gas levels showed higher similarity with that of the control forest soil. Our results implied that the effect of SO2 exposure exerted a selective pressure on the pioneer community structure by changing the surrounding environment of the microbes.

  10. DNA damage in mouse lymphocytes exposed to curcumin and copper.

    PubMed

    Urbina-Cano, Patricia; Bobadilla-Morales, Lucina; Ramírez-Herrera, Mario A; Corona-Rivera, Jorge R; Mendoza-Magaña, Maria L; Troyo-Sanromán, Rogelio; Corona-Rivera, Alfredo

    2006-01-01

    Dietary polyphenolics, such as curcumin, have shown antioxidant and anti-inflammatory effects. Some antioxidants cause DNA strand breaks in excess of transition metal ions, such as copper. The aim of this study was to evaluate the in vitro effect of curcumin in the presence of increasing concentrations of copper to induce DNA damage in murine leukocytes by the comet assay. Balb-C mouse lymphocytes were exposed to 50 microM curcumin and various concentrations of copper (10 microM, 100 microM and 200 microM). Cellular DNA damage was detected by means of the alkaline comet assay. Our results show that 50 microM curcumin in the presence of 100-200 microM copper induced DNA damage in murine lymphocytes. Curcumin did not inhibit the oxidative DNA damage caused by 50 microM H2O2 in mouse lymphocytes. Moreover, 50 microM curcumin alone was capable of inducing DNA strand breaks under the tested conditions. The increased DNA damage by 50 mM curcumin was observed in the presence of various concentrations of copper, as detected by the alkaline comet assay.

  11. Response of ocean bottom dwellers exposed to underwater shock waves

    NASA Astrophysics Data System (ADS)

    Hosseini, S. H. R.; Kaiho, Kunio; Takayama, Kazuyoshi

    2016-01-01

    The paper reports results of experiments to estimate the mortality of ocean bottom dwellers, ostracoda, against underwater shock wave exposures. This study is motivated to verify the possible survival of ocean bottom dwellers, foraminifera, from the devastating underwater shock waves induced mass extinction of marine creatures which took place at giant asteroid impact events. Ocean bottom dwellers under study were ostracoda, the replacement of foraminifera, we readily sampled from ocean bottoms. An analogue experiment was performed on a laboratory scale to estimate the domain and boundary of over-pressures at which marine creatures' mortality occurs. Ostracods were exposed to underwater shock waves generated by the explosion of 100mg PETN pellets in a chamber at shock over-pressures ranging up to 44MPa. Pressure histories were measured simultaneously on 113 samples. We found that bottom dwellers were distinctively killed against overpressures of 12MPa and this value is much higher than the usual shock over-pressure threshold value for marine-creatures having lungs and balloons.

  12. Cytogenetic monitoring of nuclear workers occupationally exposed to ionising radiation.

    PubMed

    Gricienė, B; Slapšytė, G; Mierauskienė, J

    2014-06-01

    Chromosome aberration (CA) analysis using Giemsa techniques was performed in blood lymphocytes of 84 nuclear workers with cumulative doses of 1-632 mSv during employment periods of 1-25 y. The control group comprised 82 healthy male donors. An estimated CA frequency in the total radiation-exposed group was significantly higher when compared with the controls (2.27 vs. 1.76 CA/100 cells, p < 0.05). CA analyses revealed no significant differences between workers with external gamma radiation exposure and the controls (1.60 vs. 1.76 CA/100 cells, p > 0.05). However, significant increase in the total CA frequency was determined in workers with additional internal exposure (2.54 CA/100 cells, p < 0.05) and those with registered neutron doses (2.95 CA/100 cells, p < 0.01). No correlation was found between CA frequency and occupational exposure dose. Borderline significant correlation was found between duration of employment and total CA (r = 0.218, p = 0.046, Fig. 2) and chromosome-type aberration (r = 0.265, p = 0.015) frequency.

  13. Response of bush bean exposed to acid mist

    SciTech Connect

    Hindawi, I.J.; Rea, J.A.; Griffis, W.L.

    1980-01-01

    Bush bean plants (Phaseolus vulgaris l. Cv. contender) were treated once a week for six weeks with simulated acid mist at five pH levels ranging from 5.5 to 2.0. Leaf injury developed on plants exposed to acid concentrations below pH 3 and many leaves developed a flecking symptom similar to that caused by ozone. An adaxial, interveinal bleached area resembling SO/sub 2/ injury also developed on some trifoliate leaves at the low pH treatments. Microscopic observation of injured trifoliates indicated that the pallisade cells were plasmolyzed and that the chloroplasts lost structural integrity. Reductions in plant weight and chlorophyll content were detected across the pH gradient. Seed and pod growth were reduced at some intermediate acid depositions even though no visible foliar injury developed. Foliar losses of nitrogen, calcium, magnesium and phosphorous increased with decreases in acid mist pH, whereas foliar potassium concentrations were unaffected by acid mist treatment.

  14. Phenolic metabolism of Matricaria chamomilla plants exposed to nickel.

    PubMed

    Kovácik, Jozef; Klejdus, Borivoj; Backor, Martin

    2009-09-01

    We examined accumulation of phenolic acids, total soluble phenolics and flavonoids, and activities of phenolic metabolism-related enzymes (shikimate dehydrogenase (SKDH), phenylalanine ammonia-lyase (PAL), cinnamyl alcohol dehydrogenase (CAD), polyphenol oxidase (PPO)) in Matricaria chamomilla plants exposed to 3, 60 and 120 microM of nickel (Ni) for 10 days. Ni showed low toxicity as indicated by unaltered content of total soluble phenolics in the leaf rosettes. In the roots, the effects of Ni were more visible, including increased total phenolics and PAL activity, but a decrease in PPO activity was observed. CAD activity was not affected by any of the Ni concentrations. Cinnamic acid derivatives were affected more than benzoic acid derivatives. Accumulation of chlorogenic acid, an important antioxidant compound, was enhanced by Ni treatment (ca. 4-fold in 120 microM Ni). Accumulation of protocatechuic acid, a phenol with high chelating strength, even decreased in the leaf rosettes. These observations are discussed in connection to antioxidative properties of phenolic metabolites and previously tested metals (cadmium and copper).

  15. Medical monitoring of asbestos-exposed workers: experience from Poland

    PubMed Central

    Szeszenia-Dąbrowska, Neonila; Wilczyńska, Urszula

    2016-01-01

    Abstract In Poland, the use of asbestos was banned in 1997 and asbestos plants have been closed since then. Despite their closure, cases of asbestos-related occupational diseases among former asbestos workers are still being recorded in the Central Register of Occupational Diseases. Between 2001 and 2014, there were 2726 asbestos-related illnesses, classified and reported as diseases associated with occupational exposure to asbestos. In 2000, Poland introduced a programme called Amiantus, targeted at former asbestos-processing plant workers. The programme provided periodic medical examinations to workers and free access to medications for treatment of asbestos-related illnesses. Introduction of the programme provided additional data to generate a reliable estimation of the number of asbestos-related occupational diseases, including cancer. The average latency period for asbestosis, lung cancer and mesothelioma is about 40 years so there may still be some health impact to former workers necessitating follow-up. We present the Polish experience of implementing a medical examination programme for asbestos-exposed workers and provide a list of activities to consider when planning for such a programme. PMID:27516637

  16. Chromosome aberrations in ataxia telangiectasia cells exposed to heavy ions

    NASA Astrophysics Data System (ADS)

    Kawata, T.; Cucinotta, F.; George, K.; Wu, H.; Shigematsu, N.; Furusawa, Y.; Uno, T.; Isobe, K.; Ito, H.

    Understanding of biological effects of heavy ions is important to assess healt h risk in space. One of the most important issues may be to take into account individual susceptibility. Ataxia telangiectasia (A-T) cells are known to exhibit abnormal responses to radiations but the mechanism of hyper radiosensitivity of A-T still remains unknown. We report chromosome aberrations in normal human fibroblasts and AT fibroblasts exposed to low- and high-LET radiations. A chemical-induced premature chromosome condensation (PCC) technique combined with chromosome- painting technique was applied to score chromosome aberrations in G2/M-phase cells. Following gamma irradiation, GM02052 cells were approximately 5 times more sensitive to g-rays than AG1522 cells. GM02052 cells had a much higher frequency of deletions and misrejoining than AG1522 cells. When the frequency of complex type aberrations was compared, GM02052 cells showed more than 10 times higher frequency than AG1522 cells. The results will be compared with those obtained from high-LET irradiations.

  17. WASTE CHARACTERIZATION OF POLYMERIC COMPONENTS EXPOSED TO TRITIUM GAS

    SciTech Connect

    Clark, E

    2008-02-15

    A recent independent review led to uncertainty about the technical basis for characterizing the residual amount of tritium in polymer components used in the Savannah River Site Tritium Facilities that are sent for waste disposal. A review of a paper published in the open literature firmly establishes the basis of the currently used characterization, 10 Ci/cc. Information provided in that paper about exposure experiments performed at the DOE Mound Laboratory allows the calculation of the currently used characterization. These experiments involved exposure of high density polyethylene (HD-PE) to initially 1 atm tritium gas. In addition, a review of recent research at the Savannah River Site not only further substantiates this characterization, but also establishes its use for ultra-high molecular weight polyethylene (UHMW-PE), polytetrafluoroethylene (PTFE, a trade name is Teflon{reg_sign}), and Vespel{reg_sign} polyimide. 10 Ci/cc tritium is a representative characterization for any type of polymer components exposed at ambient temperature and at approximately 1 atm. tritium gas.

  18. Optimization of Routine Monitoring of Workers Exposed to Plutonium Aerosols.

    PubMed

    Davesne, Estelle; Quesne, Benoit; De Vita, Antoine; Chojnacki, Eric; Blanchardon, Eric; Franck, Didier

    2016-10-01

    In case of incidental confinement failure, mixed oxide (MOX) fuel preparation may expose workers to plutonium aerosols. Due to its potential toxicity, occupational exposure to plutonium compounds should be kept as low as reasonably achievable. To ensure the absence of significant intake of radionuclides, workers at risk of internal contamination are monitored by periodic bioassay planned in a routine monitoring programme. From bioassay results, internal dose may be estimated. However, accurate dose calculation relies on known exposure conditions, which are rarely available when the exposure is demonstrated by routine monitoring only. Therefore, internal dose calculation is subject to uncertainty from unknown exposure conditions and from activity measurement variability. The present study calculates the minimum detectable dose (MDD) for a routine monitoring programme by considering all plausible conditions of exposure and measurement uncertainty. The MDD evaluates the monitoring quality and can be used for optimization. Here, MDDs were calculated for the monitoring of workers preparing MOX fuel. Uncertain parameters were modelled by probability distributions defined according to information provided by experts of routine monitoring, of workplace radiological protection and of bioassay analysis. Results show that the current monitoring is well adapted to potential exposure. A sensitivity study of MDD highlights high dependence on exposure condition modelling. Integrating all expert knowledge is therefore crucial to obtain reliable MDD estimates, stressing the value of a holistic approach to worker monitoring.

  19. The muscle activity of trout exposed to unsteady flow.

    PubMed

    Klein, Adrian; Bleckmann, Horst

    2017-02-23

    In running water trout seek out special regions for station holding. Trout exposed to flow fluctuations caused by a cylinder hold station immediately upstream of the cylinder (bow wake region), adjacent to the cylinder (entraining region) or downstream of the cylinder (Kármán gait). In addition it was shown that the activity of the axial red swimming muscles is reduced during Kármán gaiting. Up to now only the two-dimensional (horizontal) extensions of the above regions have been examined. We determined both, the horizontal and vertical extension of the Kármán gait, entraining and bow wake region by continuously recording the position (spatial resolution 1 cm(3)) of trout for 3 h. In addition we continuously recorded the trunk muscle activity. The Kármán gate region had the smallest vertical extension (13 cm, water level 28-29 cm, length of the submerged cylinder 27 cm), followed by the entraining (21 cm) and bow wake region (25 cm). A fourth so far unknown region used for station holding was immediately below a stationary surface wave which, at flow velocities ≥36 cm s(- 1), developed slightly downstream of the cylinder. While in any of the above regions the activity of the axial swimming muscles was significantly reduced.

  20. Synthesis of protein in intestinal cells exposed to cholera toxin

    SciTech Connect

    Peterson, J.W.; Berg, W.D. Jr.; Coppenhaver, D.H.

    1987-11-01

    The mechanism by which cyclic adenosine monophosphate (AMP), formed by intestinal epithelial cells in response to cholera toxin, ultimately results in alterations in water and electrolyte transport is poorly understood. Several studies have indicated that inhibitors of transcription or translation block much of the transport of ions and water in the intestine and edema formation in tissue elicited by cholera toxin. Data presented in this study confirmed the inhibitory effects of cycloheximide on cholera toxin-induced fluid accumulation in the rabbit intestinal loop model. Neither cycloheximide nor actinomycin D altered the amount of cyclic AMP that accumulated in intestinal cells and Chinese hamster ovary cells exposed to cholera toxin. An increase in (/sup 3/H) leucine incorporation was readily demonstrable in intestinal epithelial cells from rabbits challenged with Vibrio cholerae. Similarly, intestinal epithelial cells incubated with cholera toxin for 4 hr synthesized substantially more protein than controls as determined by relative incorporation of (/sup 35/S) methionine. Most of the new protein synthesized in response to cholera toxin was membrane associated and of high molecular weight. The possible significance of the toxin-induced protein relative to cholera pathogenesis was discussed.

  1. Optical flow estimation on image sequences with differently exposed frames

    NASA Astrophysics Data System (ADS)

    Bengtsson, Tomas; McKelvey, Tomas; Lindström, Konstantin

    2015-09-01

    Optical flow (OF) methods are used to estimate dense motion information between consecutive frames in image sequences. In addition to the specific OF estimation method itself, the quality of the input image sequence is of crucial importance to the quality of the resulting flow estimates. For instance, lack of texture in image frames caused by saturation of the camera sensor during exposure can significantly deteriorate the performance. An approach to avoid this negative effect is to use different camera settings when capturing the individual frames. We provide a framework for OF estimation on such sequences that contain differently exposed frames. Information from multiple frames are combined into a total cost functional such that the lack of an active data term for saturated image areas is avoided. Experimental results demonstrate that using alternate camera settings to capture the full dynamic range of an underlying scene can clearly improve the quality of flow estimates. When saturation of image data is significant, the proposed methods show superior performance in terms of lower endpoint errors of the flow vectors compared to a set of baseline methods. Furthermore, we provide some qualitative examples of how and when our method should be used.

  2. Blistering on tungsten surface exposed to high flux deuterium plasma

    NASA Astrophysics Data System (ADS)

    Xu, H. Y.; Liu, W.; Luo, G. N.; Yuan, Y.; Jia, Y. Z.; Fu, B. Q.; De Temmerman, G.

    2016-04-01

    The blistering behaviour of tungsten surfaces exposed to very high fluxes (1-2 × 1024/m2/s) of low energy (38 eV) deuterium plasmas was investigated as a function of ion fluence (0.2-7 × 1026 D/m2) and surface temperature (423-873 K). Blisters were observed under all conditions, especially up to temperatures of 873 K. The blister parameters are evaluated with blister size, blister density and surface coverage. The blister size always peaked at less than 0.5 μm and no blister larger than 10 μm is observed even at high fluence. The blister densities are found in high magnitude of 106 blisters/m2, with the surface coverages lower than 2%. The formation of cracks in the sub-surface region was observed by cross-section imaging. Changes in blister size and shape with fluence and temperature suggest processes of predominantly nucleation and subsequent growth of blisters. The smaller blister size is considered to be caused by a combination of flux-related effects such as enhanced defect formation in the near surface region, reduced deuterium diffusivity and relatively short exposure times.

  3. Exposing region duplication through local geometrical color invariant features

    NASA Astrophysics Data System (ADS)

    Gong, Jiachang; Guo, Jichang

    2015-05-01

    Many advanced image-processing softwares are available for tampering images. How to determine the authenticity of an image has become an urgent problem. Copy-move is one of the most common image forgery operations. Many methods have been proposed for copy-move forgery detection (CMFD). However, most of these methods are designed for grayscale images without any color information used. They are usually not suitable when the duplicated regions have little structure or have undergone various transforms. We propose a CMFD method using local geometrical color invariant features to detect duplicated regions. The method starts by calculating the color gradient of the inspected image. Then, we directly take the color gradient as the input for scale invariant features transform (SIFT) to extract color-SIFT descriptors. Finally, keypoints are matched and clustered before their geometrical relationship is estimated to expose the duplicated regions. We evaluate the detection performance and computational complexity of the proposed method together with several popular CMFD methods on a public database. Experimental results demonstrate the efficacy of the proposed method in detecting duplicated regions with various transforms and poor structure.

  4. Exposing variation to aid climate change risk assessment

    NASA Astrophysics Data System (ADS)

    Smith, M. J.; Purves, D. W.; Joppa, L. N.; Emmott, S.; Lyutsarev, V.; Bishop, C. M.; Palmer, P. I.; Calderhead, B.; Vanderwel, M. C.

    2015-12-01

    Considerable efforts to quantify different sources of variation in climate change projections (some might say uncertainty) have led to a welcome set of additional information on which to base confidence about what and how different futures might unfold and how different types of mediating efforts might affect the future. Quantifying the impacts of these different sources of variation on key climate change projection metrics should be used in part to guide future model development efforts. I will report on several of my team's recent research projects to better quantify and assess the importance of different sources of variation. I will show how we use inference techniques to estimate parameter uncertainty in land and marine carbon components of earth system models by comparing them with observational evidence and show how we propagate such uncertainty to better assess how such systems might respond to climate change and quantify the impact of reducing uncertainty for different applications. I will also show how we use such techniques on simulation models themselves to identify key sources of variation in their predictions: helping to pinpoint important focal areas for model improvement. Lastly, I will show a new software prototype being designed to enable any user to view climate model projections alongside historical and recent observational evidence while, importantly, also exposing some of the variation / uncertainty in the reported information.

  5. Measuring exposed magnetic fields of welders in working time.

    PubMed

    Yamaguchi-Sekino, Sachiko; Ojima, Jun; Sekino, Masaki; Hojo, Minoru; Saito, Hiroyuki; Okuno, Tsutomu

    2011-01-01

    The assessment of the occupational electromagnetic field exposure of welders is of great importance, especially in shielded-arc welding, which uses relatively high electric currents of up to several hundred amperes. In the present study, we measured the magnetic field exposure level of welders in the course of working. A 3-axis Hall magnetometer was attached to a subject's wrist in order to place the sensor probe at the closest position to the magnetic source (a cable from the current source). Data was acquired every 5 s from the beginning of the work time. The maximum exposed field was 0.35-3.35 mT (Mean ± SD: 1.55 ± 0.93 mT, N=17) and the average value per day was 0.04-0.12 mT (Mean ± SD: 0.07 ± 0.02 mT, N=17). We also conducted a finite element method-based analysis of human hand tissue for the electromagnetic field dosimetry. In addition, the magnetic field associated with grinders, an air hammer, and a drill using electromagnetic anchorage were measured; however, the magnetic fields were much lower than those generated in the welding process. These results agreed well with the results of the electromagnetic field dosimetry (1.49 mT at the wrist position), and the calculated eddy current (4.28 mA/m(2)) was much lower than the well-known guideline thresholds for electrical nerve or muscular stimulation.

  6. Reproductive effects in birds exposed to pesticides and industrial chemicals.

    PubMed

    Fry, D M

    1995-10-01

    Environmental contamination by agricultural chemicals and industrial waste disposal results in adverse effects on reproduction of exposed birds. The diversity of pollutants results in physiological effects at several levels, including direct effects on breeding adults as well as developmental effects on embryos. The effects on embryos include mortality or reduced hatchability, failure of chicks to thrive (wasting syndrome), and teratological effects producing skeletal abnormalities and impaired differentiation of the reproductive and nervous systems through mechanisms of hormonal mimicking of estrogens. The range of chemical effects on adult birds covers acute mortality, sublethal stress, reduced fertility, suppression of egg formation, eggshell thinning, and impaired incubation and chick rearing behaviors. The types of pollutants shown to cause reproductive effects include organochlorine pesticides and industrial pollutants, organophosphate pesticides, petroleum hydrocarbons, heavy metals, and in a fewer number of reports, herbicides, and fungicides. o,p'-DDT, polychlorinated biphenyls (PCBs), and mixtures of organochlorines have been identified as environmental estrogens affecting populations of gulls breeding in polluted "hot spots" in southern California, the Great Lakes, and Puget Sound. Estrogenic organochlorines represent an important class of toxicants to birds because differentiation of the avian reproductive system is estrogen dependent.

  7. Reproductive effects in birds exposed to pesticides and industrial chemicals

    SciTech Connect

    Fry, D.M.

    1995-10-01

    Environmental contamination by agricultural chemicals and industrial waste disposal results in adverse effects on reproduction of exposed birds. The diversity of pollutants results in physiological effects at several levels, including direct effects on breeding adults as well as developmental effects on embryos. The effects on embryos include mortality or reduced hatchability, failure of chicks to thrive (wasting syndrome), and teratological effects producing skeletal abnormalities and impaired differentiation of the reproductive and nervous systems through mechanisms of hormonal mimicking of estrogens. The range of chemical effects on adult birds covers acute mortality, sublethal stress, reduced fertility, suppression of egg formation, eggshell thinning, and impaired incubation and chick rearing behaviors. The types of pollutants shown to cause reproductive effects include organochlorine pesticides and industrial pollutants, organophosphate pesticides, petroleum hydrocarbons, heavy metals, and in a fewer number of reports, herbicides, and fungicides. o,p`-DDT, polychlorinated biphenyls (PCBs), and mixtures of organochlorines have been identified as environmental estrogens affecting populations of gulls breeding in polluted {open_quotes}hot spots{close_quotes} in southern California, the Great Lakes, and Puget Sound. Estrogenic organochlorines represent an important class of toxicants to birds because differentiation of the avian reproductive system is estrogen dependent. 85 refs.

  8. Critical organ concentration of cadmium in occupationally-exposed workers

    SciTech Connect

    Ellis, K.J.; Morgan, W.D.; Yasumura, S.; Vartsky, D.; Zanzi, I.; Cohn, S.H.

    1981-01-01

    This report describes the present Brookhaven facility for in vivo measurements of cadmium in man and provides a comparison with other portable systems. The cadmium detection limits are 2.2 mg in the kidney and 1.5 ppM in the liver for the Brookhaven system. In a recent field study, the cadmium content of the left kidney and concentration in the liver were measured in 82 occupationally exposed workers and 10 control subjects. Organ content ranged up to 57 mg in the kidney and up to 120 ppM in the liver for the industrial group. By contrast, the values for the control group ranged from 0.4 to 11.8 mg for the kidney and 0.7 to 7.9 ppM for the liver. The geometric means were 3.7 mg for the kidney and 2.7 ppM for the liver in the control group. When the data were analyzed to provide an estimate of the critical concentration for the kidney, a range of 300 to 400 ..mu..g/g for the renal cortex was calculated. The corresponding cadmium concentrations in the liver and urine were 30 to 42 ppM (liver) and 22 to 28 ..mu..g/g creatinine (urine), respectively. Blood and urine levels of cadmium and ..beta../sub 2/-microgloubin were also evaluated as possible biological indicators of organ content.

  9. Identifying redundancy and exposing provenance in crowdsourced data analysis.

    PubMed

    Willett, Wesley; Ginosar, Shiry; Steinitz, Avital; Hartmann, Björn; Agrawala, Maneesh

    2013-12-01

    We present a system that lets analysts use paid crowd workers to explore data sets and helps analysts interactively examine and build upon workers' insights. We take advantage of the fact that, for many types of data, independent crowd workers can readily perform basic analysis tasks like examining views and generating explanations for trends and patterns. However, workers operating in parallel can often generate redundant explanations. Moreover, because workers have different competencies and domain knowledge, some responses are likely to be more plausible than others. To efficiently utilize the crowd's work, analysts must be able to quickly identify and consolidate redundant responses and determine which explanations are the most plausible. In this paper, we demonstrate several crowd-assisted techniques to help analysts make better use of crowdsourced explanations: (1) We explore crowd-assisted strategies that utilize multiple workers to detect redundant explanations. We introduce color clustering with representative selection--a strategy in which multiple workers cluster explanations and we automatically select the most-representative result--and show that it generates clusterings that are as good as those produced by experts. (2) We capture explanation provenance by introducing highlighting tasks and capturing workers' browsing behavior via an embedded web browser, and refine that provenance information via source-review tasks. We expose this information in an explanation-management interface that allows analysts to interactively filter and sort responses, select the most plausible explanations, and decide which to explore further.

  10. Antioxidant status in MgO nanoparticle-exposed rats.

    PubMed

    Kiranmai, G; Reddy, A Rama Narsimha

    2013-11-01

    In this present study, antioxidant status was evaluated in rat serum following exposure to magnesium oxide (MgO) nanoparticles. The lungs of rats were intratracheally instilled with (single dose) phosphate-buffered saline (PBS) + 1% of Tween 80 (solvent control) or MgO or carbonyl iron (negative control) or quartz particles (positive control) at a dose of 1 and 5 mg/kg of body weight. The blood samples were collected at 1, 7, and 30 days of postinstillation of nanoparticles after their exposure, and different parameters were estimated to assess the oxidative stress induced by the instillation of MgO. Exposure of rats to MgO produced a significant (p < 0.05) dose-dependent reduction in blood total antioxidant capacity, superoxide dismutase, and catalase activity levels than PBS + 1% Tween 80 control group. This reduction in the antioxidant capacity in MgO nanoparticle-exposed rats indicates the reduction in antioxidant defense mechanisms due to the instillation of MgO. These results indicate that exposure to MgO nanoparticles induces oxidative stress by reducing the total antioxidant capacity in rats. The findings suggest possible occupational health hazard in chronic exposures.

  11. Salivary biomarkers of neural hypervigilance in trauma-exposed women

    PubMed Central

    Yoon, Seungyeon A.; Weierich, Mariann R.

    2015-01-01

    Objectives More than half of all adults will be exposed to a traumatic event at some point in their lives, yet we do not yet have reliable biomarkers to help predict who experiences trauma-related symptoms in response to exposure. We tested the utility of salivary cortisol and salivary alpha amylase as markers of (1) neural reactivity to negative affective information and (2) neural hypervigilance in the absence of threat. Participants 20 women (mean age 23.6 +/− 5.8 years) with a history of trauma exposure. Measures Salivary cortisol and alpha amylase reactivity were measured in response to a trauma reminder during a clinical interview. Neural reactivity to novel and familiar affective scenes was measured in a later session using functional magnetic resonance imaging. Results Salivary alpha amylase, but not cortisol, increased in response to the trauma reminder. Salivary alpha amylase reactivity was associated with neural reactivity in the salience network in response to novel negative scenes and neural hypervigilance as indexed by reactivity to novel neutral scenes. Conclusions Salivary alpha amylase might serve as a more reliable marker of trauma-related reactivity to negative affective information, and also as a marker of hypervigilance in the absence of threatening information. PMID:26398002

  12. Subaerially exposed Holocene coral reef, Enriquillo Valley, Dominican Republic

    NASA Technical Reports Server (NTRS)

    Mann, P.; Taylor, F. W.; Burke, K.; Kulstad, R.

    1984-01-01

    An extremely well-preserved Holocene fringing coral reef occurs at an average elevation of 5 m below sea level around the margins of the central Enriquillo Valley, Dominican Republic. The reef records the latest marine incursion from the east into an 85-km-long, 12-km-wide tectonic depression and appears to represent a unique preservation. Excellent cross sections of the reef exposed in erosional gullies reveal a composition and zonation typical of modern Caribbean reefs that are found in offshore low-energy environments. Radiocarbon age determinations (2) indicate that reef growth coincided with sea-level rise following the last ice age (5,930 + or - 100 to 4,760 + or - 90 yr B.P.). Deltaic deposition and possible vertical movements on active fault scarps dammed the eastern mouth of the valley and created Lago Enriquillo, the level of which was then rapidly lowered by evaporation in an arid climate to produce a saline lake approximately 40 m below sea level. Stratigraphic studies of rocks along the valley edge and data from drill holes in the basin center indicate that there were earlier post-Miocene marine incursions similar to that described here.

  13. An epidemiological study of workers potentially exposed to ethylene oxide.

    PubMed

    Wong, O; Trent, L S

    1993-04-01

    This epidemiological study was of 18,728 employees at 14 United States facilities producing sterilised medical supplies and spices, who were potentially exposed to ethylene oxide (EO) for at least 90 days. The mortality of the cohort was studied to the end of 1988. A total of 1353 deaths was identified. The cohort had a significantly lower mortality than the general population from all causes, all cancers, and non-malignant diseases. In the entire cohort, mortality was not significantly increased from any of the cancer sites examined. In particular, no significant increase in mortality was found in the cancer sites of interest based on previous studies--namely, stomach, leukaemia (including major specific cell types), pancreas, and brain. The lack of an increased mortality for these cancer sites was further strengthened by the lack of a dose-response relation with duration of employment and latency. Among the men, a statistically significant increase in mortality from non-Hodgkin's lymphoma was found. There was no indication for a dose-response relation for non-Hodgkin's lymphoma and no specific job categories seemed to be responsible for the increase. Among the women, a deficit of non-Hodgkin's lymphoma was found, which was not consistent with the finding in the men. Therefore, the increase among the men did not seem to be related to exposure to EO.

  14. An epidemiological study of workers potentially exposed to ethylene oxide.

    PubMed Central

    Wong, O; Trent, L S

    1993-01-01

    This epidemiological study was of 18,728 employees at 14 United States facilities producing sterilised medical supplies and spices, who were potentially exposed to ethylene oxide (EO) for at least 90 days. The mortality of the cohort was studied to the end of 1988. A total of 1353 deaths was identified. The cohort had a significantly lower mortality than the general population from all causes, all cancers, and non-malignant diseases. In the entire cohort, mortality was not significantly increased from any of the cancer sites examined. In particular, no significant increase in mortality was found in the cancer sites of interest based on previous studies--namely, stomach, leukaemia (including major specific cell types), pancreas, and brain. The lack of an increased mortality for these cancer sites was further strengthened by the lack of a dose-response relation with duration of employment and latency. Among the men, a statistically significant increase in mortality from non-Hodgkin's lymphoma was found. There was no indication for a dose-response relation for non-Hodgkin's lymphoma and no specific job categories seemed to be responsible for the increase. Among the women, a deficit of non-Hodgkin's lymphoma was found, which was not consistent with the finding in the men. Therefore, the increase among the men did not seem to be related to exposure to EO. PMID:8494770

  15. Exposing SAMOS Data and Vocabularies within the Semantic Web

    NASA Astrophysics Data System (ADS)

    Dockery, Nkemdirim; Elya, Jocelyn; Smith, Shawn

    2014-05-01

    As part of the Ocean Data Interoperability Platform (ODIP), we at the Center for Ocean-Atmospheric Prediction Studies (COAPS) will present the development process for the exposure of quality-controlled data and core vocabularies managed by the Shipboard Automated Meteorological Oceanographic System (SAMOS) initiative using Semantic Web technologies. Participants in the SAMOS initiative collect continuous navigational (position, course, heading, speed), meteorological (winds, pressure, temperature, humidity, radiation), and near-surface oceanographic (sea temperature, salinity) parameters while at sea. One-minute interval observations are packaged and transmitted back to COAPS via daily emails, where they undergo standardized formatting and quality control. The authors will present methods used to expose these daily datasets. The Semantic Web, a vision of the World Wide Web Consortium, focuses on extending the principles of the web from connecting documents to connecting data. The creation of a web of Linked Data that can be used across different applications in a machine-readable way is the ultimate goal. The Resource Description Framework (RDF) is the standard language and format used in the Semantic Web. RDF pages may be queried using the SPARQL Protocol and RDF Query Language (SPARQL). The authors will showcase the development of RDF resources that map SAMOS vocabularies to internationally served vocabularies such as those found in the Natural Environment Research Council (NERC) Vocabulary Server. Each individual SAMOS vocabulary term (data parameter and quality control flag) will be described in an RDF resource page. These RDF resources will define each SAMOS vocabulary term and provide a link to the mapped vocabulary term (or multiple terms) served externally. Along with enhanced retrieval by parameter, time, and location, we will be able to add additional parameters with the confidence that they follow an international standard. The production of RDF

  16. Aquatic plants exposed to pharmaceuticals: effects and risks.

    PubMed

    Brain, Richard A; Hanson, Mark L; Solomon, Keith R; Brooks, Bryan W

    2008-01-01

    largely overlooked in the risk assessment process to date, which typically relies heavily on physiological and/or morphological endpoints for deriving toxicity data. However, a small number of studies have indicated that measuring the response of a pathway- or receptor-specific target in conjunction with a physiological endpoint with direct relatedness can yield sublethal responses that are two to three times more sensitive that the traditional gross morphological endpoints typically employed in risk assessment. The risk assessment for this review was based almost entirely on evaluations of gross morphological endpoints, which generally indicated that the risk pharmaceuticals pose to aquatic plants is generally low, with a few exceptions, particularly blue-green algae exposed to antibiotics, and both green and blue-green algae exposed to triclosan. It is critical to note, however, that the application of sublethal pathway or receptor-specific responses in risk assessment has largely been unconsidered, and future research is needed to elucidate whether evaluating the toxicity of pharmaceuticals using these endpoints provides a more sensitive, subtle, yet meaningful indication of toxicity than the traditional endpoints used in prospective and retrospective risk assessments for aquatic plants.

  17. Polyamines and polyamine biosynthesis in cells exposed to hyperthermia

    SciTech Connect

    Gerner, E.W.; Stickney, D.G.; Herman, T.S.; Fuller, D.J.

    1983-02-01

    The issue of how polyamines act to sensitize cultured cells to the lethal effects of hyperthermia was investigated using Chinese hamster cells which were induced to express thermotolerance. Intracellular levels of these naturally occurring polycations were manipulated in certain situations by treating whole cells with methylglyoxal bis-(guanylhydrazone), an inhibitor of the S-adenosyl-L-methionine decarboxylases. Exogenous spermine as low as 100 ..mu..M in the culture media dramatically sensitized cells expressing thermotolerance to the lethal effects of subsequent 42/sup 0/C exposures. When thermotolerance was differentially induced in cultures exposed to 42.4/sup 0/C by varying the rate of heating from 37 to 42.4/sup 0/C, the most resistant cells and the highest levels of intracellular spermidine and spermine. This finding was explainable in part by the observation that the putrescine-dependent S-adenosyl-L-methionine decarboxylase activity was minimally affected in cells expressng the greatest degree of thermotolerance. When this enzyme activity was inhibited by drug, lowered intracellular polyamine levels did not correspond with subsequent survival responses to heat. Interestingly, cultures treated with methylglyoxal bis-(guanylhydrazone) 24 hr previous to heat exposure showed a reduced capacity to express rate of heating-induced thermotolerance. Together, these results demonstrate that the polyamines, especially spermidine and spermine, enhance hyperthermia-induced cell killing by some mechanism involving the plasma membrane. Further, our data suggest that methylglyoxal bis-(guanylhydrazone) can act to affect thermal responses by a mechanism(s) other than modification of intracellular polyamine levels.

  18. Dating and quantification of erosion processes based on exposed roots

    NASA Astrophysics Data System (ADS)

    Stoffel, Markus; Corona, Christophe; Ballesteros-Cánovas, Juan Antonio; Bodoque, José Maria

    2013-08-01

    Soil erosion is a key driver of land degradation and heavily affects sustainable land management in various environments worldwide. An appropriate quantification of rates of soil erosion and a localization of hotspots are therefore critical, as sediment loss has been demonstrated to have drastic consequences on soil productivity and fertility. A consistent body of evidence also exists for a causal linkage between global changes and the temporal frequency and magnitude of erosion, and thus calls for an improved understanding of dynamics and rates of soil erosion for an appropriate management of landscapes and for the planning of preventive or countermeasures. Conventional measurement techniques to infer erosion rates are limited in their temporal resolution or extent. Long-term erosion rates in larger basins have been analyzed with cosmogenic nuclides, but with lower spatial and limited temporal resolutions, thus limiting the possibility to infer micro-geomorphic and climatic controls on the timing, amount and localization of erosion. If based on exposed tree roots, rates of erosion can be inferred with up to seasonal resolution, over decades to centuries of the past and for larger surfaces with homogenous hydrological response units. Root-based erosion rates, thus, constitute a valuable alternative to empirical or physically-based approaches, especially in ungauged basins, but will be controlled by individual or a few extreme events, so that average annual rates of erosion might be highly skewed. In this contribution, we review the contribution made by this biomarker to the understanding of erosion processes and related landform evolution. We report on recent progress in root-based erosion research, illustrate possibilities, caveats and limitations of reconstructed rates, and conclude with a call for further research on various aspects of root-erosion research and for work in new geographic regions.

  19. Ethnic minority health in Vietnam: a review exposing horizontal inequity

    PubMed Central

    Målqvist, Mats; Hoa, Dinh Thi Phuong; Liem, Nguyen Thanh; Thorson, Anna; Thomsen, Sarah

    2013-01-01

    Background Equity in health is a pressing concern and reaching disadvantaged populations is necessary to close the inequity gap. To date, the discourse has predominately focussed on reaching the poor. At the same time and in addition to wealth, other structural determinants that influence health outcomes exist, one of which is ethnicity. Inequities based on group belongings are recognised as ‘horizontal’, as opposed to the more commonly used notion of ‘vertical’ inequity based on individual characteristics. Objective The aim of the present review is to highlight ethnicity as a source of horizontal inequity in health and to expose mechanisms that cause and maintain this inequity in Vietnam. Design Through a systematic search of available academic and grey literature, 49 publications were selected for review. Information was extracted on: a) quantitative measures of health inequities based on ethnicity and b) qualitative descriptions explaining potential reasons for ethnicity-based health inequities. Results Five main areas were identified: health-care-seeking and utilization, maternal and child health, nutrition, infectious diseases, and oral health and hygiene. Evidence suggests the presence of severe health inequity in health along ethnic lines in all these areas. Research evidence also offers explanations derived from both external and internal group dynamics to this inequity. It is reported that government policies and programs appear to be lacking in culturally adaptation and sensitivity, and examples of bad attitudes and discrimination from health staff toward minority persons were identified. In addition, traditions and patriarchal structures within ethnic minority groups were seen to contribute to the maintenance of harmful health behaviors within these groups. Conclusion Better understandings of the scope and pathways of horizontal inequities are required to address ethnic inequities in health. Awareness of ethnicity as a determinant of health, not

  20. Respiratory Kinetics of Marine Bacteria Exposed to Decreasing Oxygen Concentrations

    PubMed Central

    Gong, Xianzhe; Garcia-Robledo, Emilio; Schramm, Andreas

    2015-01-01

    During aerobic respiration, microorganisms consume oxygen (O2) through the use of different types of terminal oxidases which have a wide range of affinities for O2. The Km values for O2 of these enzymes have been determined to be in the range of 3 to 200 nmol liter−1. In this study, we examined the time course of development of aerobic respiratory kinetics of four marine bacterial species (Dinoroseobacter shibae, Roseobacter denitrificans, Idiomarina loihiensis, and Marinobacter daepoensis) during exposure to decreasing O2 concentrations. The genomes of all four species have genes for both high-affinity and low-affinity terminal oxidases. The respiration rate of the bacteria was measured by the use of extremely sensitive optical trace O2 sensors (range, 1 to 1,000 nmol liter−1). Three of the four isolates exhibited apparent Km values of 30 to 60 nmol liter−1 when exposed to submicromolar O2 concentrations, but a decrease to values below 10 nmol liter−1 was observed when the respiration rate per cell was lowered and the cell size was decreased due to starvation. The fourth isolate did not reach a low respiration rate per cell during starvation and exhibited apparent Km values of about 20 nmol liter−1 throughout the experiment. The results clearly demonstrate not only that enzyme kinetics may limit O2 uptake but also that even individual cells may be diffusion limited and that this diffusion limitation is the most pronounced at high respiration rates. A decrease in cell size by starvation, due to limiting organic carbon, and thereby more efficient diffusion uptake may also contribute to lower apparent Km values. PMID:26682857

  1. Magnetic behavioural change of silane exposed graphene nanoflakes

    SciTech Connect

    Ray, Sekhar C.; Mishra, D. K.; Strydom, A. M.; Papakonstantinou, P.

    2015-09-21

    The electronic structures and magnetic properties of graphene nanoflakes (GNFs) exposed to an organo-silane precursor [tetra-methyl-silane, Si(CH{sub 3}){sub 4}] were studied using atomic force microscopy, electron field emission (EFE), x-ray photoelectron spectroscopy (XPS), and magnetization. The result of XPS indicates that silyl radical based strong covalent bonds were formed in GNFs, which induced local structural relaxations and enhanced sp{sup 3} hybridization. The EFE measurements show an increase in the turn-on electric field from 9.8 V/μm for pure GNFs to 26.3 V/μm for GNFs:Si having highest Si/(Si + C) ratio ( ≅ 0.35) that also suggests an enhancement of the non-metallic sp{sup 3} bonding in the GNFs matrix. Magnetic studies show that the saturation magnetization (Ms) is decreased from 172.53 × 10{sup −6} emu/g for pure GNFs to 13.00 × 10{sup −6} emu/g for GNFs:Si with the highest Si/(Si + C) ratio 0.35, but on the other side, the coercivity (Hc) increases from 66 to 149 Oe due to conversion of sp{sup 2} → sp{sup 3}-hybridization along with the formation of SiC and Si-O bonding in GNFs. The decrease in saturation magnetization and increase in coercivity (Hc) in GNFs on Si-functionalization are another routes to tailor the magnetic properties of graphene materials for magnetic device applications.

  2. Immunotoxicity Monitoring in a Population Exposed to Polychlorinated Biphenyls.

    PubMed

    Haase, Hajo; Fahlenkamp, Astrid; Schettgen, Thomas; Esser, Andre; Gube, Monika; Ziegler, Patrick; Kraus, Thomas; Rink, Lothar

    2016-03-08

    The relationship between polychlorinated biphenyl (PCB) burden and several indicators of immune function was investigated as part of the HELPcB (Health Effects in High-Level Exposure to PCB) program, offering bio-monitoring to workers, relatives, and neighbors exposed to PCBs by a German transformers and capacitors recycling company. The present retrospective observational study evaluates the correlation of plasma levels of total PCBs, five indicator congeners (28, 101, 138, 153, 180), and seven dioxin-like congeners (105, 114, 118, 156, 157, 167, 189) with several parameters of immune function. The cross-sectional study was performed immediately after the end of exposure (258 subjects), and one (218 subjects), and two (177 subjects) years later. At the first time point, measurements showed significant positive correlation between congeners with low to medium chlorination and the relative proportion of CD19 positive B-cells among lymphocytes, as well as a negative correlation of PCB114 with serum IgM, and of PCB 28 with suppressor T-cell and NK-cell numbers. Congeners with a high degree of chlorination, in particular PCB157 and 189, were positively associated with expression of the activation marker CD25 on T-cells in the cohort of the second time point. No associations between PCB levels and IFN-y production by T-cells and killing by NK-cells were found. In conclusion, there were several effects on the cellular composition of adaptive immunity, affecting both T- and B-cells. However, the values were not generally outside the reference ranges for healthy adult individuals and did not indicate overt functional immunodeficiency, even in subjects with the uppermost PCB burden.

  3. Ultrasonic emissions from conifer xylem exposed to repeated freezing.

    PubMed

    Mayr, Stefan; Zublasing, Verena

    2010-01-01

    Ultrasonic emission measurements enable the analysis of xylem cavitation induced by drought and freeze-thaw events. Several studies have indicated that ultrasonic acoustic emissions (UAE) in conifers occur upon freezing and not upon thawing, although classical theory has postulated gas bubble formation during freezing and cavitation during thawing. We analyzed the pattern and quality of freeze-thaw-induced UAE in seven conifers (Abies alba, Larix decidua, Juniperus communis, Picea abies, Pinus cembra, Pinus mugo, Pinus sylvestris). Axes samples dehydrated to different water potentials were exposed to repeated frost cycles. The number, amplitude and energy of UAE signals were registered and related to water potential, temperature course and wood characteristics (wood density, tracheid diameter). For P. abies, ultrasonic emission analysis was also performed on bark samples, xylem samples without bark, as well as on stems of young potted trees. In all conifers, UAE were registered in water-stressed samples but not in saturated or dehydrated samples. No signals were emitted by the bark of P. abies. Ultrasonic activity occurred only upon freezing, and identical patterns were observed in axes samples and stems of potted P. abies trees. A weak positive relationship between tracheid diameter and UAE energy was observed, indicating wide tracheids to emit signals with higher energy. The classical bubble formation hypothesis cannot sufficiently explain the occurrence of UAE during freezing and upon repeated temperature cycles, as demonstrated in this study. We suggest that the low water potential of ice induces air-seeding near the ice-water interface, and consequently, causes UAE.

  4. Cloning assay thresholds on cells exposed to ultrafast laser pulses

    NASA Astrophysics Data System (ADS)

    Koenig, Karsten; Riemann, Iris; Fischer, Peter; Becker, Thomas P.; Oehring, Hartmut; Halbhuber, Karl-Juergen

    1999-06-01

    The influence of the peak power, laser wavelength and the pulse duration of near infrared (NIR) ultrashort laser pulses on the reproduction behavior of Chinese hamster ovary (CHO) cells has been studied. In particular we determined the cloning efficiency of single cell pairs after exposure to ultrashort laser pulses with an intensity in the range of GW/cm2 and TW/cm2. A total of more than 3500 non- labeled cells were exposed to a highly focused scanning beam of a multiphoton laser microscope with 60 microsecond pixel dwell time per scan. The beam was provided by a tunable argon ion laser pumped mode-locked 76 MHz Titanium:Sapphire laser as well as by a compact solid-state laser based system (Vitesse) at a fixed wavelength of 800 nm. Pulse duration (tau) was varied in the range of 100 fs to 4 ps by out-of-cavity pulse- stretching units consisting of SF14 prisms and blazed gratings. Within an optical (laser power) window CHO cells could be scanned for hours without severe impact on reproduction behavior, morphology and vitality. Ultrastructural studies reveal that mitochondria are the major targets of intense destructive laser pulses. Above certain laser power P thresholds, CHO cells started to delay or failed to undergo cell division and, in part, to develop uncontrolled cell growth (giant cell formation). The damage followed a P2/(tau) relation which is typical for a two-photon excitation process. Therefore, cell damage was found to be more pronounced at shorter pulses. Due to the same P2/(tau) relation for the efficiency of fluorescence excitation, two- photon microscopy of living cells does not require extremely short femtosecond laser pulses nor pulse compression units. Picosecond as well as femtosecond layers can be used as efficient light sources in safe two photon fluorescence microscopy. Only in three photon fluorescence microscopy, femtosecond laser pulses are advantageous over picosecond pulses.

  5. Cloning assay thresholds on cells exposed to ultrafast laser pulses

    NASA Astrophysics Data System (ADS)

    Koenig, Karsten; Riemann, Iris; Fischer, Peter; Becker, Thomas P.; Oehring, Hartmut; Halbhuber, Karl-Juergen

    1999-06-01

    The influence of the peak power, laser wavelength and the pulse duration of near infrared ultrashort laser pulses on the reproduction behavior of Chinese hamster ovary (CHO) cells has been studied. In particular, we determined the cloning efficiency of single cell pairs after exposure to ultrashort laser pulses with an intensity in the range of GW/cm2 and TW/cm2. A total of more than 3500 non- labeled cells were exposed to a highly focused scanning beam of a multiphoton laser microscope with 60 microsecond(s) pixel dwell time per scan. The beam was provided by a tunable argon ion laser pumped mode-locked 76 MHz Titanium:Sapphire laser as well as by a compact solid-state laser based system (Vitesse) at a fixed wavelength of 800 nm. Pulse duration (tau) was varied in the range of 100 fs to 4 ps by out-of- cavity pulse-stretching units consisting of SF14 prisms and blazed gratings. Within an optical (laser power) window CHO cells could be scanned for hours without severe impact on reproduction behavior, morphology and vitality. Ultrastructural studies reveal that mitochondria are the major targets of intense destructive laser pulses. Above certain laser power P thresholds, CHO cells started to delay or failed to undergo cell division and, in part, to develop uncontrolled cell growth (giant cell formation). The damage followed a P2/(tau) relation which is typical for a two- photon excitation process. Therefore, cell damage was found to be more pronounced at shorter pulses. Due to the same P2/(tau) relation for the efficiency of fluorescence excitation, two-photon microscopy of living cells does not require extremely short femtosecond laser pulses nor pulse compression units. Picosecond as well as femtosecond lasers can be used as efficient light sources in safe two photon fluorescence microscopy. Only in three photon fluorescence microscopy, femtosecond laser pulses are advantageous over picosecond pulses.

  6. Acetylcholine and choline levels in rabbit fetuses exposed to anticholinergics.

    PubMed

    McBride, W G; Hicks, L J

    1987-01-01

    It has been hypothesized that acetylcholine, choline acetylase and acetylcholinesterase may have an ontogenic and trophic influence in the embryo, and that therefore certain drugs may produce malformations via their effect on the acetylcholine and choline levels in the fetus. Thalidomide and the anticholinergics, scopolamine hydrobromide and orphenadrine hydrochloride, and doxylamine succinate, an antihistamine with secondary anticholinergic action, were administered to pregnant New Zealand White rabbit does from day 8 to day 15 of gestation. Cesarean sections were performed on gestational day 16, the fetuses removed and the acetylcholine and choline contents of the fetuses and placentas were estimated by organic extraction and derivation for injection into a GCMS. These acetylcholine and choline levels were compared with those of the fetuses and placentas of the control animals mated with the same buck on the same day as the treated animals. Thalidomide (50 mg/kg) did not affect acetylcholine or choline levels in the fetuses or the placentas obtained from the treated animal. Scopolamine (approximately 100 micrograms/kg) reduced the choline level in the placenta and fetus but not the acetylcholine levels. Orphenadrine (approximately 24 mg/kg) reduced acetylcholine and choline levels in the fetus and choline levels in the placenta. Doxylamine succinate (10 mg/kg) reduced the acetylcholine levels in the fetus and the choline levels in the placenta. The placenta is a fetal organ and the significance of acetylcholine production by the placenta is as yet unknown. The reduction in acetylcholine levels in the fetus exposed to drugs with an anticholinergic action may be of significance in the production of malformations.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Asymmetric Hearing Loss in Chinese Workers Exposed to Complex Noise

    PubMed Central

    Wang, Xiaoxiao; Li, Nan; Zeng, Lin; Tao, Liyuan; Zhang, Hua; Yang, Qiuling; Qiu, Wei; Zhu, Liangliang; Zhao, Yiming

    2015-01-01

    Objectives Evaluate audiometric asymmetry in Chinese industrial workers and investigate the effects of noise exposure, sex, and binaural average thresholds on audiometric asymmetry. Design Data collected from Chinese industrial workers during a cross-sectional study were re-analyzed. Of the 1388 workers, 266 met the inclusion criteria for this study. Each subject underwent a physical examination and an otologic examination and completed a health-related questionnaire. χ2 and t tests were used to examine the differences between the asymmetric and symmetric hearing loss groups. Results One hundred thirty-one (49.2%) subjects had a binaural hearing threshold difference of 15 dB or more for at least one frequency, and there was no statistically significant difference between the left and right ears. The asymmetric hearing loss group was not exposed to higher cumulative noise levels (t = 0.522, p = 0.602), and there was no dose-response relationship between asymmetry and cumulative noise levels (χ2 = 6.502, p = 0.165). Men were 1.849 times more likely to have asymmetry than women were [95% confidence interval (CI), 1.051–3.253]. Among the workers with higher high-frequency hearing thresholds (HFHTs), audiometric asymmetry was 1.024 times more prevalent than that among those with lower HFHTs (95% CI, 1.004–1.044). Conclusions The results indicated that occupational noise exposure contributed minimally to asymmetry, while sex and binaural average thresholds significantly affected audiometric asymmetry. There was no evidence that the left ears were worse than the right ears. PMID:26502292

  8. Transcriptome analysis of zebrafish embryos exposed to deltamethrin.

    PubMed

    Chueh, Tsung-Cheng; Hsu, Li-Sung; Kao, Chin-Ming; Hsu, Tung-Wei; Liao, Hung-Yu; Wang, Kuan-Yi; Chen, Ssu Ching

    2016-10-27

    Deltamethrin (DTM), a type II pyrethroid, is one of the most commonly used insecticides. The increased use of pyrethroid leads to potential adverse effects, particularly in sensitive populations such as children and pregnant women. None of the related studies was focused on the transcriptome responses in zebrafish embryos after treatment with DTM; therefore, RNA-seq, a high-throughput method, was performed to analyze the global expression of differential expressed genes (DEGs) in zebrafish embryos treated with DTM (40 and 80 μg/L) from fertilization to 48 h postfertilization (hpf) as compared with that in the control group (without DTM treatment). Two cDNA libraries were generated from treated embryos and one cDNA library from nontreated embryos, respectively. Over 92% of reads mapped to the reference in these three libraries. It was observed that many differential genes were expressed in comparison with embryos before and after DTM. The 20 most differentially expressed upregulated or downregulated genes were majorly involved in the signaling transduction. Validation of selected nine genes expression using qRT-PCR confirmed RNA-seq results. The transcriptome sequences were further subjected to gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, showing G-protein-coupled receptor signaling pathway and neuroactive ligand-receptor interaction, respectively, were most enriched. The data from this study contributed to a better understanding of the potential consequences of fish exposed to DTM, to an evaluation of the potential threat of DTM to fish populations in aquatic environments. © 2016 Wiley Periodicals, Inc. Environ Toxicol, 2016.

  9. Helium segregation on surfaces of plasma-exposed tungsten

    SciTech Connect

    Maroudas, Dimitrios; Blondel, Sophie; Hu, Lin; Hammond, Karl D.; Wirth, Brian D.

    2016-01-21

    Here we report a hierarchical multi-scale modeling study of implanted helium segregation on surfaces of tungsten, considered as a plasma facing component in nuclear fusion reactors. We employ a hierarchy of atomic-scale simulations based on a reliable interatomic interaction potential, including molecular-statics simulations to understand the origin of helium surface segregation, targeted molecular-dynamics (MD) simulations of near-surface cluster reactions, and large-scale MD simulations of implanted helium evolution in plasma-exposed tungsten. We find that small, mobile He-n (1 <= n <= 7) clusters in the near-surface region are attracted to the surface due to an elastic interaction force that provides the thermodynamic driving force for surface segregation. Elastic interaction force induces drift fluxes of these mobile Hen clusters, which increase substantially as the migrating clusters approach the surface, facilitating helium segregation on the surface. Moreover, the clusters' drift toward the surface enables cluster reactions, most importantly trap mutation, in the near-surface region at rates much higher than in the bulk material. Moreover, these near-surface cluster dynamics have significant effects on the surface morphology, near-surface defect structures, and the amount of helium retained in the material upon plasma exposure. We integrate the findings of such atomic-scale simulations into a properly parameterized and validated spatially dependent, continuum-scale reaction-diffusion cluster dynamics model, capable of predicting implanted helium evolution, surface segregation, and its near-surface effects in tungsten. This cluster-dynamics model sets the stage for development of fully atomistically informed coarse-grained models for computationally efficient simulation predictions of helium surface segregation, as well as helium retention and surface morphological evolution, toward optimal design of plasma facing components.

  10. Nickel and blood counts in workers exposed to urban stressors.

    PubMed

    Rosati, Maria Valeria; Casale, Teodorico; Ciarrocca, Manuela; Weiderpass, Elisabete; Capozzella, Assunta; Schifano, Maria Pia; Tomei, Francesco; Nieto, Hector Alberto; Marrocco, Mariasilvia; Tomei, Gianfranco; Caciari, Tiziana; Sancini, Angela

    2016-06-01

    Nickel (Ni) and Ni compounds are widely present in the urban air. The purpose of this study is to estimate exposure of individuals to Ni and the correlation between this exposure and the values of blood counts in outdoor workers. This study focused on a sample of 101 outdoor workers (55 male and 46 female; 65 nonsmokers and 36 smokers), all employed in the municipal police in a large Italian city. The personal levels of exposure to Ni were assessed through (a) environmental monitoring of Ni present in the urban air obtained from individual samples and (b) biological monitoring of urinary and blood Ni. The blood count parameters were obtained from the hemochromocytometric tests. Pearson correlation coefficients (r) were calculated to assess the association between the blood and urinary Ni and the complete blood count. Multiple linear regression models were used to examine the associations between the complete blood count and the independent variables (age, gender, years of work for current tasks, cigarette smoking habit (current and never smoker), values of airborne Ni, and blood and urinary Ni). Multiple linear regression analysis performed on the total group of 101 subjects confirms the association among the red blood cells count, the hematocrit, and the urinary Ni (R(2) = 0.520, p = 0.025 and R(2) = 0.530, p = 0.030). These results should lead to further studies on the effects of Ni in working populations exposed to urban pollutants. The possibility that the associations found in our study may be partially explained by other urban pollutants (such as benzene, toluene, and other heavy metals) not taken into consideration in this study cannot be ruled out.

  11. Brain injury and development in preterm infants exposed to fentanyl

    PubMed Central

    McPherson, Christopher; Haslam, Matthew; Pineda, Roberta; Rogers, Cynthia; Neil, Jeffrey J.; Inder, Terrie E.

    2015-01-01

    Background Fentanyl is commonly utilized in preterm infants. Relatively little is known regarding the neurodevelopmental outcomes of preterm infants exposed to fentanyl. Objective To investigate the association between cumulative fentanyl dose and brain injury and diameters in a cohort of preterm infants Methods Data on demographics, perinatal course, and neonatal course, including total fentanyl exposure prior to term equivalent age, were retrospectively evaluated for 103 infants born at ≤ 30 weeks gestational age who underwent magnetic resonance imaging at term equivalent age (mean gestational age 26.9 ± 1.8 weeks). Magnetic resonance images were evaluated for brain injury and regional brain diameters. Developmental testing was conducted at term equivalent and 2 years of age. Results Seventy-eight infants (76%) received fentanyl (median cumulative dose 3 μg/kg, interquartile range 1 – 441 μg/kg). Cumulative fentanyl dose in the first week of life correlated with the incidence of cerebellar hemorrhage after correction for covariates (OR 2.1, 95% confidence interval 1.1 – 4.1). Cumulative fentanyl dose before term equivalent age correlated with reductions in transverse cerebellar diameter after correction for covariates including the presence of cerebellar hemorrhage (r = 0.461, p = 0.002). No correlation was detected between cumulative fentanyl dose and development at 2 years of age. Conclusions Higher cumulative fentanyl dose in preterm infants correlated with a higher incidence of cerebellar injury and lower cerebellar diameter at term equivalent age. Our findings must be taken with caution, but emphasize the need for future prospective trials examining the risks and benefits of commonly utilized analgesic agents in preterm infants. PMID:26369570

  12. Limited transcriptional responses of Rickettsia rickettsii exposed to environmental stimuli.

    PubMed

    Ellison, Damon W; Clark, Tina R; Sturdevant, Daniel E; Virtaneva, Kimmo; Hackstadt, Ted

    2009-01-01

    Rickettsiae are strict obligate intracellular pathogens that alternate between arthropod and mammalian hosts in a zoonotic cycle. Typically, pathogenic bacteria that cycle between environmental sources and mammalian hosts adapt to the respective environments by coordinately regulating gene expression such that genes essential for survival and virulence are expressed only upon infection of mammals. Temperature is a common environmental signal for upregulation of virulence gene expression although other factors may also play a role. We examined the transcriptional responses of Rickettsia rickettsii, the agent of Rocky Mountain spotted fever, to a variety of environmental signals expected to be encountered during its life cycle. R. rickettsii exposed to differences in growth temperature (25 degrees C vs. 37 degrees C), iron limitation, and host cell species displayed nominal changes in gene expression under any of these conditions with only 0, 5, or 7 genes, respectively, changing more than 3-fold in expression levels. R. rickettsii is not totally devoid of ability to respond to temperature shifts as cold shock (37 degrees C vs. 4 degrees C) induced a change greater than 3-fold in up to 56 genes. Rickettsiae continuously occupy a relatively stable environment which is the cytosol of eukaryotic cells. Because of their obligate intracellular character, rickettsiae are believed to be undergoing reductive evolution to a minimal genome. We propose that their relatively constant environmental niche has led to a minimal requirement for R. rickettsii to respond to environmental changes with a consequent deletion of non-essential transcriptional response regulators. A minimal number of predicted transcriptional regulators in the R. rickettsii genome is consistent with this hypothesis.

  13. Hypoxia markers are expressed in interneurons exposed to recurrent seizures.

    PubMed

    Gualtieri, Fabio; Marinelli, Carla; Longo, Daniela; Pugnaghi, Matteo; Nichelli, Paolo F; Meletti, Stefano; Biagini, Giuseppe

    2013-03-01

    An early but transient decrease in oxygen availability occurs during experimentally induced seizures. Using pimonidazole, which probes hypoxic insults, we found that by increasing the duration of pilocarpine-induced status epilepticus (SE) from 30 to 120 min, counts of pimonidazole-immunoreactive neurons also increased (P < 0.01, 120 vs 60 and 30 min). All the animals exposed to SE were immunopositive to pimonidazole, but a different scenario emerged during epileptogenesis when a decrease in pimonidazole-immunostained cells occurred from 7 to 14 days, so that only 1 out of 4 rats presented with pimonidazole-immunopositive cells. Pimonidazole-immunoreactive cells robustly reappeared at 21 days post-SE induction when all animals (7 out of 7) had developed spontaneous recurrent seizures. Specific neuronal markers revealed that immunopositivity to pimonidazole was present in cells identified by neuropeptide Y (NPY) or somatostatin antibodies. At variance, neurons immunopositive to parvalbumin or cholecystokinin were not immunopositive to pimonidazole. Pimonidazole-immunopositive neurons expressed remarkable immunoreactivity to hypoxia-inducible factor 1α (HIF-1α). Interestingly, surgical samples obtained from pharmacoresistant patients showed neurons co-labeled by HIF-1α and NPY antibodies. These interneurons, along with parvalbumin-positive interneurons that were negative to HIF-1α, showed immunopositivity to markers of cell damage, such as high-mobility group box 1 in the cytoplasm and cleaved caspase-3 in the nucleus. These findings suggest that interneurons are continuously endangered in rodent and human epileptogenic tissue. The presence of hypoxia and cell damage markers in NPY interneurons of rats and patients presenting with recurrent seizures indicates a mechanism of selective vulnerability in a specific neuronal subpopulation.

  14. Helium segregation on surfaces of plasma-exposed tungsten

    DOE PAGES

    Maroudas, Dimitrios; Blondel, Sophie; Hu, Lin; ...

    2016-01-21

    Here we report a hierarchical multi-scale modeling study of implanted helium segregation on surfaces of tungsten, considered as a plasma facing component in nuclear fusion reactors. We employ a hierarchy of atomic-scale simulations based on a reliable interatomic interaction potential, including molecular-statics simulations to understand the origin of helium surface segregation, targeted molecular-dynamics (MD) simulations of near-surface cluster reactions, and large-scale MD simulations of implanted helium evolution in plasma-exposed tungsten. We find that small, mobile He-n (1 <= n <= 7) clusters in the near-surface region are attracted to the surface due to an elastic interaction force that provides themore » thermodynamic driving force for surface segregation. Elastic interaction force induces drift fluxes of these mobile Hen clusters, which increase substantially as the migrating clusters approach the surface, facilitating helium segregation on the surface. Moreover, the clusters' drift toward the surface enables cluster reactions, most importantly trap mutation, in the near-surface region at rates much higher than in the bulk material. Moreover, these near-surface cluster dynamics have significant effects on the surface morphology, near-surface defect structures, and the amount of helium retained in the material upon plasma exposure. We integrate the findings of such atomic-scale simulations into a properly parameterized and validated spatially dependent, continuum-scale reaction-diffusion cluster dynamics model, capable of predicting implanted helium evolution, surface segregation, and its near-surface effects in tungsten. This cluster-dynamics model sets the stage for development of fully atomistically informed coarse-grained models for computationally efficient simulation predictions of helium surface segregation, as well as helium retention and surface morphological evolution, toward optimal design of plasma facing components.« less

  15. Immunotoxicity Monitoring in a Population Exposed to Polychlorinated Biphenyls

    PubMed Central

    Haase, Hajo; Fahlenkamp, Astrid; Schettgen, Thomas; Esser, Andre; Gube, Monika; Ziegler, Patrick; Kraus, Thomas; Rink, Lothar

    2016-01-01

    The relationship between polychlorinated biphenyl (PCB) burden and several indicators of immune function was investigated as part of the HELPcB (Health Effects in High-Level Exposure to PCB) program, offering bio-monitoring to workers, relatives, and neighbors exposed to PCBs by a German transformers and capacitors recycling company. The present retrospective observational study evaluates the correlation of plasma levels of total PCBs, five indicator congeners (28, 101, 138, 153, 180), and seven dioxin-like congeners (105, 114, 118, 156, 157, 167, 189) with several parameters of immune function. The cross-sectional study was performed immediately after the end of exposure (258 subjects), and one (218 subjects), and two (177 subjects) years later. At the first time point, measurements showed significant positive correlation between congeners with low to medium chlorination and the relative proportion of CD19 positive B-cells among lymphocytes, as well as a negative correlation of PCB114 with serum IgM, and of PCB 28 with suppressor T-cell and NK-cell numbers. Congeners with a high degree of chlorination, in particular PCB157 and 189, were positively associated with expression of the activation marker CD25 on T-cells in the cohort of the second time point. No associations between PCB levels and IFN-y production by T-cells and killing by NK-cells were found. In conclusion, there were several effects on the cellular composition of adaptive immunity, affecting both T- and B-cells. However, the values were not generally outside the reference ranges for healthy adult individuals and did not indicate overt functional immunodeficiency, even in subjects with the uppermost PCB burden. PMID:27005643

  16. Transcriptomic profiling in Silurana tropicalis testes exposed to finasteride.

    PubMed

    Bissegger, Sonja; Martyniuk, Christopher J; Langlois, Valérie S

    2014-07-01

    Investigations of endocrine disrupting chemicals found in aquatic ecosystems with estrogenic and androgenic modes of action have increased over the past two decades due to a surge of evidence of adverse effects in wildlife. Chemicals that disrupt androgen signalling and steroidogenesis can result in an imbalanced conversion of testosterone (T) into 17β-estradiol (E2) and other androgens such as 5α-dihydrotestosterone (5α-DHT). Therefore, a better understanding of how chemicals perturb these pathways is warranted. In this study, the brain, liver, and testes of Silurana tropicalis were exposed ex vivo to the human drug finasteride, a potent steroid 5α-reductase inhibitor and a model compound to study the inhibition of the conversion of T into 5α-DHT. These experiments were conducted (1) to determine organ specific changes in sex steroid production after treatment, and (2) to elucidate the transcriptomic response to finasteride in testicular tissue. Enzyme-linked immunosorbent assays were used to measure hormone levels in media following finasteride incubation for 6 h. Finasteride significantly increased T levels in the media of liver and testis tissue, but did not induce any changes in E2 and 5α-DHT production. Gene expression analysis was performed in frog testes and data revealed that finasteride treatment significantly altered 1,434 gene probes. Gene networks associated with male reproduction such as meiosis, hormone biosynthesis, sperm entry, gonadotropin releasing hormone were affected by finasteride exposure as well as other pathways such as oxysterol synthesis, apoptosis, and epigenetic regulation. For example, this study suggests that the mode of action by which finasteride induces cellular damage in testicular tissue as reported by others, is via oxidative stress in testes. This data also suggests that 5-reductase inhibition disrupts the expression of genes related to reproduction. It is proposed that androgen-disrupting chemicals may mediate their

  17. Helium segregation on surfaces of plasma-exposed tungsten

    NASA Astrophysics Data System (ADS)

    Maroudas, Dimitrios; Blondel, Sophie; Hu, Lin; Hammond, Karl D.; Wirth, Brian D.

    2016-02-01

    We report a hierarchical multi-scale modeling study of implanted helium segregation on surfaces of tungsten, considered as a plasma facing component in nuclear fusion reactors. We employ a hierarchy of atomic-scale simulations based on a reliable interatomic interaction potential, including molecular-statics simulations to understand the origin of helium surface segregation, targeted molecular-dynamics (MD) simulations of near-surface cluster reactions, and large-scale MD simulations of implanted helium evolution in plasma-exposed tungsten. We find that small, mobile He n (1  ⩽  n  ⩽  7) clusters in the near-surface region are attracted to the surface due to an elastic interaction force that provides the thermodynamic driving force for surface segregation. This elastic interaction force induces drift fluxes of these mobile He n clusters, which increase substantially as the migrating clusters approach the surface, facilitating helium segregation on the surface. Moreover, the clusters’ drift toward the surface enables cluster reactions, most importantly trap mutation, in the near-surface region at rates much higher than in the bulk material. These near-surface cluster dynamics have significant effects on the surface morphology, near-surface defect structures, and the amount of helium retained in the material upon plasma exposure. We integrate the findings of such atomic-scale simulations into a properly parameterized and validated spatially dependent, continuum-scale reaction-diffusion cluster dynamics model, capable of predicting implanted helium evolution, surface segregation, and its near-surface effects in tungsten. This cluster-dynamics model sets the stage for development of fully atomistically informed coarse-grained models for computationally efficient simulation predictions of helium surface segregation, as well as helium retention and surface morphological evolution, toward optimal design of plasma facing components.

  18. Compatibility and Decontamination of High-Density Polyethylene Exposed to Sulfur Mustard

    DTIC Science & Technology

    2014-05-01

    COMPATIBILITY AND DECONTAMINATION OF HIGH-DENSITY POLYETHYLENE EXPOSED TO SULFUR MUSTARD ECBC-TR-1235...Decontamination of High-Density Polyethylene Exposed to Sulfur Mustard 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...study to determine the compatability of high-density polyethylene (HDPE) with liquid mustard (HD) material and decontamination of HDPE when exposed

  19. What's exposed? Mapping elements at risk from space

    NASA Astrophysics Data System (ADS)

    Taubenböck, Hannes; Klotz, Martin; Geiß, Christian

    2014-05-01

    The world has suffered from severe natural disasters over the last decennium. The earthquake in Haiti in 2010 or the typhoon "Haiyan" hitting the Philippines in 2013 are among the most prominent examples in recent years. Especially in developing countries, knowledge on amount, location or type of the exposed elements or people is often not given. (Geo)-data are mostly inaccurate, generalized, not up-to-date or even not available at all. Thus, fast and effective disaster management is often delayed until necessary geo-data allow an assessment of effected people, buildings, infrastructure and their respective locations. In the last decade, Earth observation data and methods have developed a product portfolio from low resolution land cover datasets to high resolution spatially accurate building inventories to classify elements at risk or even assess indirectly population densities. This presentation will give an overview on the current available products and EO-based capabilities from global to local scale. On global to regional scale, remote sensing derived geo-products help to approximate the inventory of elements at risk in their spatial extent and abundance by mapping and modelling approaches of land cover or related spatial attributes such as night-time illumination or fractions of impervious surfaces. The capabilities and limitations for mapping physical exposure will be discussed in detail using the example of DLR's 'Global Urban Footprint' initiative. On local scale, the potential of remote sensing particularly lies in the generation of spatially and thematically accurate building inventories for the detailed analysis of the building stock's physical exposure. Even vulnerability-related indicators can be derived. Indicators such as building footprint, height, shape characteristics, roof materials, location, and construction age and structure type have already been combined with civil engineering approaches to assess building stability for large areas

  20. Integrity of disposable nitrile exam gloves exposed to simulated movement.

    PubMed

    Phalen, Robert N; Wong, Weng Kee

    2011-05-01

    Every year, millions of health care, first responder, and industry workers are exposed to chemical and biological hazards. Disposable nitrile gloves are a common choice as both a chemical and physical barrier to these hazards, especially as an alternative to natural latex gloves. However, glove selection is complicated by the availability of several types or formulations of nitrile gloves, such as low-modulus, medical grade, low filler, and cleanroom products. This study evaluated the influence of simulated movement on the physical integrity (i.e., holes) of different nitrile exam glove brands and types. Thirty glove products were evaluated out-of-box and after exposure to simulated whole-glove movement for 2 hr. In lieu of the traditional 1 L water-leak test, a modified water-leak test, standardized to detect a 0.15 ± 0.05 mm hole in different regions of the glove, was developed. A specialized air inflation method simulated bidirectional stretching and whole-glove movement. A worst-case scenario with maximum stretching was evaluated. On average, movement did not have a significant effect on glove integrity (chi-square; p=0.068). The average effect was less than 1% between no movement (1.5%) and movement (2.1%) exposures. However, there was significant variability in glove integrity between different glove types (p≤0.05). Cleanroom gloves, on average, had the highest percentage of leaks, and 50% failed the water-leak test. Low-modulus and medical grade gloves had the lowest percentages of leaks, and no products failed the water-leak test. Variability in polymer formulation was suspected to account for the observed discrepancies, as well as the inability of the traditional 1 L water-leak test to detect holes in finger/thumb regions. Unexpectedly, greater than 80% of the glove defects were observed in the finger and thumb regions. It is recommended that existing water-leak tests be re-evaluated and standardized to account for product variability.

  1. Electrocardiologic and echocardiographic features of patients exposed to scorpion bite.

    PubMed

    Alan, Sait; Ulgen, Mehmet S; Soker, Murat; Geyik, Faruk; Karabulut, Aziz; Toprak, Nizamettin

    2004-01-01

    The purpose of this study is to examine clinical progress and hemodynamic and electrocardiologic features (QT depression and heart rate variability [HRV]) of patients exposed to a scorpion bite. Seventeen patients bitten by scorpions, and, as a control group, 15 healthy subjects were included in the study. Standard electrocardiograph (ECG) records, 24-hour Holter-ECG, and Doppler echocardiographic examinations were performed. Holter ECG indicated sinus tachycardia, sinus bradycardia, paroxysmal supraventricular tachycardia, atrial fibrillation, first-degree and second-degree atrioventricular block not requiring treatment, early atrial beats, and early ventricular beats in the patients at frequencies of 82%, 12%, 35%, 12%, 8%, 70%, and 47%, respectively. HRV parameters that reflected parasympathetic activity (SD 35+/-13-43+/-16, RMS-SD: 20+/-9-30+/-12, high frequency: 7.8+/-2-4.3+/-3, p<0.05) were significantly lower (p<0.05). Low frequency, which especially showed sympathetic activity (LF: 11+/-13-11+/-23, p>0.05), was similar in both groups. In addition, the LF/HF ratio, which reflected sympathovagal balance, was significantly increased in the patient group (1.5+/-1-3.0+/-2, p=0.005). Corrected QT and QT dispersion values were not significantly different with respect to the control (p>0.05). In the patient group compared to the control, a significant decrease was determined in the proportion of mitral E velocity to mitral A velocity (mEv/mAv), diastolic filling period (DFP), and left ventricular ejection fraction (LVEF), while a significant increase was noticed in pulmonary artery pressure (PAP) (mEv/mAv: 0.9+/-0.4-1.7+/-0.6, DFP: 362+/-8.5-425+/-89, LVEF: 53.1+/-6.7-68.6+/-5.8, PAP: 38.1+/-13-27.2+/-6, p<0.05). Scorpion bite leads to serious cardiovascular disorders, associated with decreased HRV, decreased systolic and diastolic functions, increased arrhythmic events, and hemodynamic disturbance with sympathetic and parasympathetic balance disturbance.

  2. Mortality patterns among workers exposed to acrylamide: 1994 follow up

    PubMed Central

    Marsh, G. M.; Lucas, L. J.; Youk, A. O.; Schall, L. C.

    1999-01-01

    OBJECTIVE: To update the mortality experience of a cohort of 8508 workers with potential exposure to acrylamide at three plants in the United States from 1984-94. METHODS: Analyses of standardised mortality ratios (SMR) with national and local rates and relative risk (RR) regression modelling were performed to assess site specific cancer risks by demographic and work history factors, and exposure indicators for acrylamide and muriatic acid. RESULTS: For the 1925-94 study period, excess and deficit overall mortality risks were found for cancer sites of interest: brain and other central nervous system (CNS) (SMR 0.65, 95% confidence interval (95% CI) 0.36 to 1.09), thyroid gland (SMR 2.11, 95% CI 0.44 to 6.17), testis and other male genital organs (SMR 0.28, 95% CI 0.01 to 1.59), and cancer of the respiratory system (SMR 1.10, 95% CI 0.99 to 1.22); however, none was significant or associated with exposure to acrylamide. A previously reported excess mortality risk of cancer of the respiratory system at one plant remained increased among workers with potential exposure to muriatic acid (RR 1.50, 95% CI 0.86 to 2.59), but was only slightly increased among workers exposed or unexposed to acrylamide. In an exploratory exposure-response analysis of rectal, oesophageal, pancreatic, and kidney cancer, we found increased SMRs for some categories of exposure to acrylamide, but little evidence of an exposure-response relation. A significant 2.26-fold risk (95% CI 1.03 to 4.29) was found for pancreatic cancer among workers with cumulative exposure to acrylamide > 0.30 mg/m3.years; however, no consistent exposure-response relations were detected with the exposure measures considered when RR regression models were adjusted for time since first exposure to acrylamide. CONCLUSION: The contribution of 1115 additional deaths and nearly 60,000 person-years over the 11 year follow up period corroborate the original cohort study findings of little evidence for a causal relation between

  3. Polymorphic trial in oxidative damage of arsenic exposed Vietnamese

    SciTech Connect

    Fujihara, Junko; Soejima, Mikiko; Yasuda, Toshihiro; Koda, Yoshiro; Kunito, Takashi; Iwata, Hisato; Tanabe, Shinsuke; Takeshita, Haruo

    2011-10-15

    Arsenic causes DNA damage and changes the cellular capacity for DNA repair. Genes in the base excision repair (BER) pathway influence the generation and repair of oxidative lesions. Single nucleotide polymorphisms (SNPs) in human 8-oxoguanine DNA glycosylase (hOGG1) Ser326Cys; apurinic/apyrimidinic endonuclease (APE1) Asp148Glu; X-ray and repair and cross-complementing group 1 (XRCC1) Arg280His and Arg399Gln in the BER genes were analyzed, and the relationship between these 4 SNPs and the urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) concentrations of 100 Vietnamese population exposed to arsenic was investigated. Individuals with hOGG1 326Cys/Cys showed significantly higher urinary 8-OHdG concentrations than did those with 326 Ser/Cys and Ser/Ser. As for APE1 Asp148Glu, heterozygous subjects showed significantly higher urinary 8-OHdG concentrations than did those homozygous for Asp/Asp. Moreover, global ethnic comparison of the allelic frequencies of the 4SNPs was performed in 10 population and previous reported data. The mutant allele frequencies of hOGG1 Ser326Cys in the Asian populations were higher than those in the African and Caucasian populations. As for APE1 Asp148Glu, Caucasians showed higher mutant frequencies than those shown by African and Asian populations. Among Asian populations, the Bangladeshi population showed relatively higher mutant allele frequencies of the APE1 Asp148Glu polymorphism. This study is the first to demonstrate the existence of genetic heterogeneity in a worldwide distribution of SNPs (hOGG1 Ser326Cys, APE1 Asp148Glu, XRCC1 Arg280His, and XRCC1 Arg399Gln) in the BER genes. - Highlights: > We showed that hOGG1 and APE1 are associated with urinary 8-OHdG concentrations. > We showed the existence of inter-ethnic differences in hOGG1 and APE1 polymorphism. > These polymorphisms is a genetic marker of susceptibility to oxidative stress.

  4. Hippocampal phosphoproteomics of F344 rats exposed to 1-bromopropane

    SciTech Connect

    Huang, Zhenlie; Ichihara, Sahoko; Oikawa, Shinji; Chang, Jie; Zhang, Lingyi; Hu, Shijie; Huang, Hanlin; Ichihara, Gaku

    2015-01-15

    1-Bromopropane (1-BP) is neurotoxic in both experimental animals and human. To identify phosphorylated modification on the unrecognized post-translational modifications of proteins and investigate their role in 1-BP-induced neurotoxicity, changes in hippocampal phosphoprotein expression levels were analyzed quantitatively in male F344 rats exposed to 1-BP inhalation at 0, 400, or 1000 ppm for 8 h/day for 1 or 4 weeks. Hippocampal protein extracts were analyzed qualitatively and quantitatively by Pro-Q Diamond gel staining and SYPRO Ruby staining coupled with two-dimensional difference in gel electrophoresis (2D-DIGE), respectively, as well as by matrix-assisted laser-desorption ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) to identify phosphoproteins. Changes in selected proteins were further confirmed by Manganese II (Mn{sup 2+})-Phos-tag SDS-polyacrylamide gel electrophoresis (SDS-PAGE). Bax and cytochrome c protein levels were determined by western blotting. Pro-Q Diamond gel staining combined with 2D-DIGE identified 26 phosphoprotein spots (p < 0.05), and MALDI-TOF/MS identified 18 up-regulated proteins and 8 down-regulated proteins. These proteins are involved in the biological process of response to stimuli, metabolic processes, and apoptosis signaling. Changes in the expression of phosphorylated 14-3-3 θ were further confirmed by Mn{sup 2+}-Phos-tag SDS-PAGE. Western blotting showed overexpression of Bax protein in the mitochondria with down-regulation in the cytoplasm, whereas cytochrome c expression was high in the cytoplasm but low in the mitochondria after 1-BP exposure. Our results suggest that the pathogenesis of 1-BP-induced hippocampal damage involves inhibition of antiapoptosis process. Phosphoproteins identified in this study can potentially serve as biomarkers for 1-BP-induced neurotoxicity. - Highlights: • 1-BP modified hippocampal phosphoproteome in rat and 23 altered proteins were identified. • 1-BP changed phosphorylation

  5. Cytogenetic evaluation of cataract patients occupationally exposed to ionizing radiation in northeast China.

    PubMed

    Zhou, D D; Yao, L; Guo, K M; Lu, C W

    2016-09-16

    Long-term radiation exposure is hazardous to health; late-onset effects of exposure to ionizing radiation (IR) pose risks to the lens, and are associated with other non-cancerous diseases. Individuals occupationally exposed to low-dose IR are prone to developing eye cataracts. Cytogenetic evaluations suggest that IR is associated with chromosomal aberrations in occupationally exposed individuals. However, data regarding the association between chromosomal aberrations in cataract patients and occupational exposure to IR is scarce. Therefore, we aimed to report the characteristics of chromosomal aberrations in cataract patients from a Chinese population, occupationally exposed to IR. We found that the average age and frequency of numerical chromosomal aberrations were significantly lower in the exposed patients as compared with that in the non-exposed patients. In addition, the frequencies of dicentric and acentric chromosomes were significantly higher in the exposed patients as compared with those in the non-exposed patients. Therefore, chronic occupational exposure to IR affects cataract development in the Chinese population. The age of cataract patients exposed to IR was significantly lower than the age of cataract onset in normal individuals. Based on this study, we suggest that there is an urgent need for improved radiation safety and eye protection in individuals exposed to IR in the work place.

  6. Aggression, physical activity levels and sex role identity in teenagers exposed in utero to MPA.

    PubMed

    Jaffe, B; Shye, D; Harlap, S; Baras, M; Lieblich, A

    1989-09-01

    Sex-dimorphic traits and behavior were measured in a 17-year old prospective study of 74 teenager boys and 98 girls who had been exposed to medroxyprogesterone acetate in utero compared with 459 boys and 546 girls not exposed. Bem Sex Role Identity scores were identical in exposed and non-exposed teenagers of each sex. There were no significant differences between MPA-exposed and non-exposed males or females on the Buss-Durkee overall aggression scale and on its assaultiveness subscale. Mothers of exposed males more often reported that teachers had complained that their offspring were naughty in school. No such difference was reported for females, nor for other school behaviors of dominance/aggression, activity, shyness and quietness. Exposed and non-exposed children were similar in the number of accidents experienced in childhood, as reported by their mothers, and in participation in competitive sports. These findings fail to support hypotheses posed by earlier researchers that exposure in utero to medroxyprogesterone acetate might alter sex-dimorphic behavior or traits in later life.

  7. Electrophoresis pattern of serum from mice exposed to different concentrations of sulfur dioxide

    NASA Technical Reports Server (NTRS)

    Singh, J.

    1977-01-01

    Three day old mice were continuously exposed to sulphur dioxide concentrations at 0ppm, 0.05ppm, 0.15ppm and 1ppm for eight weeks. At the end of the experiment, blood samples were collected and centrifuged for electrophoresis studies of the serum in 5 percent acrylamide gel. The length of bands of different serum proteins from the SO2 exposed mice was at a variance as compared with the length of bands from the control exposed mice and alpha-1 band seems to be missing from the serum of SO2 exposed mice.

  8. The Affect of the Space Environment on the Survival of Halorubrum Chaoviator and Synechococcus (Nageli): Data from the Space Experiment OSMO on EXPOSE-R

    NASA Technical Reports Server (NTRS)

    Mancinelli, R. L.

    2014-01-01

    We have shown using ESA's Biopan facility flown in Earth orbit that when exposed to the space environment for 2 weeks the survival rate of Synechococcus (Nageli), a halophilic cyanobacterium isolated from the evaporitic gypsum-halite crusts that form along the marine intertidal, and Halorubrum chaoviator a member of the Halobacteriaceae isolated from an evaporitic NaCl crystal obtained from a salt evaporation pond, were higher than all other test organisms except Bacillus spores. These results led to the EXPOSE-R mission to extend and refine these experiments as part of the experimental package for the external platform space exposure facility on the ISS. The experiment was flown in February 2009 and the organisms were exposed to low-Earth orbit for nearly 2 years. Samples were either exposed to solar ultraviolet (UV)-radiation (lambda is greater than 110 nm or lambda is greater than 200 nm, cosmic radiation (dosage range 225-320 mGy), or kept in darkness shielded from solar UV-radiation. Half of each of the UV-radiation exposed samples and dark samples were exposed to space vacuum and half kept at 105 pascals in argon. Duplicate samples were kept in the laboratory to serve as unexposed controls. Ground simulation control experiments were also performed. After retrieval, organism viability was tested using Molecular Probes Live-Dead Bac-Lite stain and by their reproduction capability. Samples kept in the dark, but exposed to space vacuum had a 90 +/- 5% survival rate compared to the ground controls. Samples exposed to full UV-radiation for over a year were bleached and although results from Molecular Probes Live-Dead stain suggested approximately 10% survival, the data indicate that no survival was detected using cell growth and division using the most probable number method. Those samples exposed to attenuated UV-radiation exhibited limited survival. Results from of this study are relevant to understanding adaptation and evolution of life, the future of life

  9. The affect of the space environment on the survival of Halorubrum chaoviator and Synechococcus (Nägeli): data from the Space Experiment OSMO on EXPOSE-R

    NASA Astrophysics Data System (ADS)

    Mancinelli, R. L.

    2015-01-01

    We have shown using ESA's Biopan facility flown in Earth orbit that when exposed to the space environment for 2 weeks the survival rate of Synechococcus (Nägeli), a halophilic cyanobacterium isolated from the evaporitic gypsum-halite crusts that form along the marine intertidal, and Halorubrum chaoviator a member of the Halobacteriaceae isolated from an evaporitic NaCl crystal obtained from a salt evaporation pond, were higher than all other test organisms except Bacillus spores. These results led to the EXPOSE-R mission to extend and refine these experiments as part of the experimental package for the external platform space exposure facility on the ISS. The experiment was flown in February 2009 and the organisms were exposed to low-Earth orbit for nearly 2 years. Samples were either exposed to solar ultraviolet (UV)-radiation (λ > 110 nm or λ > 200 nm, cosmic radiation (dosage range 225-320 mGy), or kept in darkness shielded from solar UV-radiation. Half of each of the UV-radiation exposed samples and dark samples were exposed to space vacuum and half kept at 105 pascals in argon. Duplicate samples were kept in the laboratory to serve as unexposed controls. Ground simulation control experiments were also performed. After retrieval, organism viability was tested using Molecular Probes Live-Dead Bac-Lite stain and by their reproduction capability. Samples kept in the dark, but exposed to space vacuum had a 90 +/- 5% survival rate compared to the ground controls. Samples exposed to full UV-radiation for over a year were bleached and although results from Molecular Probes Live-Dead stain suggested ~10% survival, the data indicate that no survival was detected using cell growth and division using the most probable number method. Those samples exposed to attenuated UV-radiation exhibited limited survival. Results from of this study are relevant to understanding adaptation and evolution of life, the future of life beyond earth, the potential for interplanetary

  10. A well-preserved Cambrian impact exposed in Central Sweden

    NASA Astrophysics Data System (ADS)

    Lindström, Maurits; Ekvall, Johan; Hagenfeldt, Stefan E.; Säwe, Brigitta; Sturkell, Erik F. F.

    1991-02-01

    The Lockne impact crater south of Östersund formed in the early Middle Cambrian with a diameter of 7 km. It is identified by its rim wall of crushed Precambrian basement granite, by fragments of impact melt, and by grains of shocked quartz. The exceptional preservation, in particular of the rim wall, is due to a complicated geological history, the first stage of which consisted of burial by marine sediments. This stage lasted until the Middle Ordovician, or over 50 million years. An early Caradoc lowering of the sea-level may have induced debris flows that stripped the rim wall of much of its sedimentary cover. Because normal marine sedimentation recommenced soon after this event, the structure was not seriously damaged, as it was buried again. The Caledonian orogeny emplaced an overthrust nappe as ultimate protection, which was removed by a recent erosion episode from all but the center of the structure. Structures formed by the impact of extraterrestrial bodies are very rare throughout much of Europe, because such structures are neither well preserved nor displayed in young mountain belts or sedimentary basins. However, northern Europe has several ascertained structures of this kind ( Svensson & Wickman, 1965; Svensson, 1968; Bruun & Dahlman, 1982; Kala et al., 1984; Flodén et al., 1986; Wickman, 1988). Unfortunately, the hitherto known structures are either poorly preserved or hidden by younger deposits. We are reporting the discovery of a well-preserved exposed and accessible impact structure that has escaped the notice of geologists although important features of it have been described and puzzled over by generations of researchers ( Wiman, 1900; Hadding, 1927; Thorslund, 1940; Lindström et al., 1983). The structure is located in the Lockne area to the south of Östersund in central Sweden. It has a diameter of 7 km and its center is near Tramsta on the northwest shore of Lake Locknesjön (Fig. 1). Its middle is covered by folded Lower to Middle Ordovician

  11. SCM Paste Samples Exposed To Aggressive Solutions. Cementitious Barriers Partnership

    SciTech Connect

    Foster, T.

    2014-12-01

    This report summarizes experimental work performed by SIMCO Technologies Inc. (SIMCO) as part of the Cementitious Barriers Partnership (CBP) project. The test series followed an experimental program dedicated to the study of ordinary Portland cement (OPC) hydrated cement pastes exposed to aggressive solutions. In the present study, the scope is extended to hydrated cement pastes incorporating supplementary cementitious materials (SCM) such as fly ash and ground granulated blast furnace slag (GGBFS). Also, the range of aggressive contact solutions was expanded. The experimental program aimed at testing aggressive contact solutions that more closely mimic the chemical composition of saltstone pore solution. Five different solutions, some of which incorporated high levels of carbonate and nitrate, were placed in contact with four different hydrated cement paste mixes. In all solutions, 150 mmol/L of SO42– (14 400 ppm) were present. The solutions included different pH conditions and different sodium content. Two paste mixes were equivalent to Vault 1/4 and Vault 2 concrete mixes used at SRS in storage structures. Two additional paste mixes, cast at the same water-to-cement ratio and using the same cements but without SCMs, were also tested. The damage evolution in samples was monitored using ultrasonic pulse velocity (UPV) and mass measurements. After three and twelve months of exposure conditions, samples were taken out of solution containers and analyzed to perform migration tests and porosity measurements. Globally, results were in line with the previous study and confirmed that high pH may limit the formation of some deleterious phases like gypsum. In this case, ettringite may form but is not necessarily associated with damage. However, the high concentration of sodium may be associated with the formation of an AFm-like mineral called U-phase. The most significant evidences of damage were all associated with the Vault 2 paste analog. This

  12. [Medical examination of workers exposed to lead in the Philippines].

    PubMed

    Makino, S; Matsuno, K; Hisanaga, N; Seki, Y; Ortega, V S; Villanueva, M B; Cucueco, M T; Yu-Sison, S; Castro, F T

    1994-03-01

    The medical examination of workers exposed to lead was conducted as part of the activity of the Occupational Safety and Health Center (OSHC) Project in the Philippines (JICA Project). The subjects of the medical examination were 21 male and 193 female workers of a semi-conductor plant (abbreviated A company), 59 male and 6 female workers of a refrigerator manufacture (B company); 199 male workers of a storage battery manufacturer (C company); and 107 male and 6 female workers of a lead smelter (D company). Among the examination items were questions regarding occupational history, subjective complaints and objective signs, determination of blood lead levels, urine delta aminolevulinic acid levels, and examination for anemia. The survey was conducted from June to September in 1990. The following results were obtained: 1) The mean age of the workers ranged from 21.8 to 33.8 years. Those of companies A and B were younger than those of companies C and D. The mean employment duration of males at C company was 10.7 yr, and the longest among the four companies. That in both sexes for A company was 1.8 yr and the shortest among the above mentioned companies. 2) The blood lead geometric mean levels of companies C and D showed the highest concentration. The level in males of C company was 64.5 micrograms/dl and that of D company was 80.8 micrograms/dl. The level in females of A company was 9.9 micrograms/dl and the lowest in concentration. The urine delta aminolevulinic acid geometric mean levels were less than 6.0 mg/l in the four companies. There was no company having hemoglobin mean values less than 14.0 g/dl in males or less than 12.0 g/dl in females. 3) The proportion of blood lead levels of 60 micrograms/dl or more was 67.3% in males of C company, and 89.7% in males and 16.7% in females of D company. The proportion of urine delta aminolevulinic acid levels of 6 mg/l or more was 1.0% in females of A company, 20.1% in males of C company, and 43.0% in males of D company

  13. Conservation and management of crayfishes: Lessons from Pennsylvania

    USGS Publications Warehouse

    Lieb, D.A.; Bouchard, R.W.; Carline, R.F.; Nuttall, T.R.; Wallace, J.R.; Burkholder, C.L.

    2011-01-01

    North America's crayfish fauna is diverse, ecologically important, and highly threatened. Unfortunately, up-to-date information is scarce, hindering conservation and management efforts. In Pennsylvania and nearby states, recent efforts allowed us to determine the conservation status of several native crayfishes and develop management strategies for those species. Due to rarity and proximity to urban centers and introduced (exotic) crayfishes, Cambarus (Puncticambarus) sp., an undescribed member of the Cambarus acuminatus complex, is critically imperiled in Pennsylvania and possibly range-wide. Orconectes limosus is more widespread; however, recent population losses have been substantial, especially in Pennsylvania and northern Maryland, where its range has declined (retreated eastward) by greater than 200 km. Introduced congeners likely played a major role in those losses. Although extirpated from some areas, Cambarus bartonii bartonii remains widespread and is not an immediate conservation concern. In light of these findings, the role of barriers (e.g., dams), environmental protection, educational programs, and regulations in preventing crayfish invasions and conserving native crayfishes is discussed, and management initiatives centered on those factors are presented. The need for methods to eliminate exotics and monitor natives is highlighted. Although tailored to a specific regional fauna, these ideas have broad applicability and would benefit many North American crayfishes. ?? copyright 2011. Periodicals postage paid at Bethesda.

  14. The significance of droughts for hyporheic dwellers: evidence from freshwater crayfish

    PubMed Central

    Kouba, Antonín; Tíkal, Jan; Císař, Petr; Veselý, Lukáš; Fořt, Martin; Příborský, Josef; Patoka, Jiří; Buřič, Miloš

    2016-01-01

    Freshwater biodiversity is globally threatened by various factors while severe weather events like long-term droughts may be substantially devastating. In order to remain in contact with the water or stay in a sufficiently humid environment at drying localities, the ability to withstand desiccation by dwelling in the hyporheic zone, particularly through vertical burrowing is crucial. We assessed the ability of three European native and five non-native crayfish as models to survive and construct vertical burrows in a humid sandy-clayey substrate under a simulated one-week drought. Three native species (Astacus astacus, A. leptodactylus, and Austropotamobius torrentium) suffered extensive mortalities. Survival of non-native species was substantially higher while all specimens of Cherax destructor and Procambarus clarkii survived. The native species and Pacifastacus leniusculus exhibited no ability to construct vertical burrows. Procambarus fallax f. virginalis and P. clarkii constructed bigger and deeper burrows than C. destructor and Orconectes limosus. In the context of predicted weather fluctuations, the ability to withstand desiccation through constructing vertical burrows into the hyporheic zone under drought conditions might play a significant role in the success of particular crayfish species, as well as a wide range of further hyporheic-dwelling aquatic organisms in general. PMID:27225308

  15. The significance of droughts for hyporheic dwellers: evidence from freshwater crayfish

    NASA Astrophysics Data System (ADS)

    Kouba, Antonín; Tíkal, Jan; Císař, Petr; Veselý, Lukáš; Fořt, Martin; Příborský, Josef; Patoka, Jiří; Buřič, Miloš

    2016-05-01

    Freshwater biodiversity is globally threatened by various factors while severe weather events like long-term droughts may be substantially devastating. In order to remain in contact with the water or stay in a sufficiently humid environment at drying localities, the ability to withstand desiccation by dwelling in the hyporheic zone, particularly through vertical burrowing is crucial. We assessed the ability of three European native and five non-native crayfish as models to survive and construct vertical burrows in a humid sandy-clayey substrate under a simulated one-week drought. Three native species (Astacus astacus, A. leptodactylus, and Austropotamobius torrentium) suffered extensive mortalities. Survival of non-native species was substantially higher while all specimens of Cherax destructor and Procambarus clarkii survived. The native species and Pacifastacus leniusculus exhibited no ability to construct vertical burrows. Procambarus fallax f. virginalis and P. clarkii constructed bigger and deeper burrows than C. destructor and Orconectes limosus. In the context of predicted weather fluctuations, the ability to withstand desiccation through constructing vertical burrows into the hyporheic zone under drought conditions might play a significant role in the success of particular crayfish species, as well as a wide range of further hyporheic-dwelling aquatic organisms in general.

  16. Comparing Early Language Development in Monolingual- and Bilingual- Exposed Young Children with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Ohashi, J. Kaori; Mirenda, Pat; Marinova-Todd, Stefka; Hambly, Catherine; Fombonne, Eric; Szatmari, Peter; Bryson, Susan; Roberts, Wendy; Smith, Isabel; Vaillancourt, Tracy; Volden, Joanne; Waddell, Charlotte; Zwaigenbaum, Lonnie; Georgiades, Stelios; Duku, Eric; Thompson, Ann

    2012-01-01

    The purpose of this study was to compare a group of recently diagnosed bilingual-exposed children with autism (n = 20) aged 24-2 months with a matched group of monolingual-exposed children with autism (n = 40). The groups were matched with regard to chronological age at the time of language assessment and nonverbal IQ score, then compared with…

  17. 30 CFR 77.508 - Lightning arresters, ungrounded and exposed power conductors and telephone wires.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... power conductors and telephone wires. 77.508 Section 77.508 Mineral Resources MINE SAFETY AND HEALTH... arresters, ungrounded and exposed power conductors and telephone wires. All ungrounded, exposed power conductors and telephone wires shall be equipped with suitable lightning arresters which are...

  18. 30 CFR 77.508 - Lightning arresters, ungrounded and exposed power conductors and telephone wires.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... power conductors and telephone wires. 77.508 Section 77.508 Mineral Resources MINE SAFETY AND HEALTH... arresters, ungrounded and exposed power conductors and telephone wires. All ungrounded, exposed power conductors and telephone wires shall be equipped with suitable lightning arresters which are...

  19. 30 CFR 77.508 - Lightning arresters, ungrounded and exposed power conductors and telephone wires.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... power conductors and telephone wires. 77.508 Section 77.508 Mineral Resources MINE SAFETY AND HEALTH... arresters, ungrounded and exposed power conductors and telephone wires. All ungrounded, exposed power conductors and telephone wires shall be equipped with suitable lightning arresters which are...

  20. 30 CFR 77.508 - Lightning arresters, ungrounded and exposed power conductors and telephone wires.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... power conductors and telephone wires. 77.508 Section 77.508 Mineral Resources MINE SAFETY AND HEALTH... arresters, ungrounded and exposed power conductors and telephone wires. All ungrounded, exposed power conductors and telephone wires shall be equipped with suitable lightning arresters which are...

  1. 30 CFR 77.508 - Lightning arresters, ungrounded and exposed power conductors and telephone wires.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... power conductors and telephone wires. 77.508 Section 77.508 Mineral Resources MINE SAFETY AND HEALTH... arresters, ungrounded and exposed power conductors and telephone wires. All ungrounded, exposed power conductors and telephone wires shall be equipped with suitable lightning arresters which are...

  2. Attachment Status in Children Prenatally Exposed to Cocaine and Other Substances

    ERIC Educational Resources Information Center

    Seifer, Ronald; LaGasse, Linda L.; Lester, Barry; Bauer, Charles R.; Shankaran, Seetha; Bada, Henrietta S.; Wright, Linda L.; Smeriglio, Vincent L.; Liu, Jing

    2004-01-01

    Attachment status of children exposed in utero to cocaine, opiates, and other substances was examined at 18 months (n=860) and 36 months (n=732) corrected age. Children exposed to cocaine and opiates had slightly lower rates of attachment security (but not disorganization), and their insecurity was skewed toward ambivalent, rather than avoidant,…

  3. 77 FR 39264 - Meeting of the Attorney General's National Task Force on Children Exposed to Violence

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-02

    ... Violence AGENCY: Office of Justice Programs (OJP), Justice. ACTION: Notice of meeting. SUMMARY: This is an announcement of a meeting of the Attorney General's National Task Force on Children Exposed to Violence (the..., with valuable advice in the areas of children exposed to violence for the purpose of addressing...

  4. 77 FR 12881 - Hearing of the Attorney General's National Task Force on Children Exposed to Violence

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-02

    ... Violence AGENCY: Office of Justice Programs (OJP), Justice. ACTION: Notice of hearing. SUMMARY: This is an announcement of the third hearing of the Attorney General's National Task Force on Children Exposed to Violence... Justice, with valuable advice in the areas of children exposed to violence for the purpose of...

  5. 49 CFR 195.569 - Do I have to examine exposed portions of buried pipelines?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.569 Do I have to examine... exposed, you must examine the exposed portion for evidence of external corrosion if the pipe is bare, or if the coating is deteriorated. If you find external corrosion requiring corrective action...

  6. 49 CFR 195.569 - Do I have to examine exposed portions of buried pipelines?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.569 Do I have to examine... exposed, you must examine the exposed portion for evidence of external corrosion if the pipe is bare, or if the coating is deteriorated. If you find external corrosion requiring corrective action...

  7. 49 CFR 195.569 - Do I have to examine exposed portions of buried pipelines?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.569 Do I have to examine... exposed, you must examine the exposed portion for evidence of external corrosion if the pipe is bare, or if the coating is deteriorated. If you find external corrosion requiring corrective action...

  8. Membrane stability of winter wheat plants exposed to subzero temperatures for variable lengths of time

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ability to survive episodes of subfreezing temperature is essential to winter wheat. Fully cold-acclimated plants of six lines of winter wheat were exposed to -12, -14, -16 or -18° C, four 1-5 hours. Electrolyte leakage and plant survival were used to assess damage to the plants. Plants exposed ...

  9. 9 CFR 73.8 - Cattle infected or exposed during transit.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... transit. 73.8 Section 73.8 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... SCABIES IN CATTLE § 73.8 Cattle infected or exposed during transit. (a) Healthy cattle from unquarantined State exposed en route. Should healthy cattle in transit from a State not quarantined by the...

  10. 9 CFR 73.8 - Cattle infected or exposed during transit.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... transit. 73.8 Section 73.8 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... SCABIES IN CATTLE § 73.8 Cattle infected or exposed during transit. (a) Healthy cattle from unquarantined State exposed en route. Should healthy cattle in transit from a State not quarantined by the...

  11. 9 CFR 73.8 - Cattle infected or exposed during transit.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... transit. 73.8 Section 73.8 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... SCABIES IN CATTLE § 73.8 Cattle infected or exposed during transit. (a) Healthy cattle from unquarantined State exposed en route. Should healthy cattle in transit from a State not quarantined by the...

  12. 9 CFR 73.8 - Cattle infected or exposed during transit.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... transit. 73.8 Section 73.8 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... SCABIES IN CATTLE § 73.8 Cattle infected or exposed during transit. (a) Healthy cattle from unquarantined State exposed en route. Should healthy cattle in transit from a State not quarantined by the...

  13. 9 CFR 73.8 - Cattle infected or exposed during transit.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... transit. 73.8 Section 73.8 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... SCABIES IN CATTLE § 73.8 Cattle infected or exposed during transit. (a) Healthy cattle from unquarantined State exposed en route. Should healthy cattle in transit from a State not quarantined by the...

  14. 9 CFR 85.5 - Interstate movement of infected swine or exposed swine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Interstate movement of infected swine or exposed swine. 85.5 Section 85.5 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION... PRODUCTS PSEUDORABIES § 85.5 Interstate movement of infected swine or exposed swine. Infected swine...

  15. 9 CFR 85.5 - Interstate movement of infected swine or exposed swine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Interstate movement of infected swine or exposed swine. 85.5 Section 85.5 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION... PRODUCTS PSEUDORABIES § 85.5 Interstate movement of infected swine or exposed swine. Infected swine...

  16. 9 CFR 85.5 - Interstate movement of infected swine or exposed swine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Interstate movement of infected swine or exposed swine. 85.5 Section 85.5 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION... PRODUCTS PSEUDORABIES § 85.5 Interstate movement of infected swine or exposed swine. Infected swine...

  17. 9 CFR 85.5 - Interstate movement of infected swine or exposed swine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Interstate movement of infected swine or exposed swine. 85.5 Section 85.5 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION... PRODUCTS PSEUDORABIES § 85.5 Interstate movement of infected swine or exposed swine. Infected swine...

  18. 9 CFR 85.5 - Interstate movement of infected swine or exposed swine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Interstate movement of infected swine or exposed swine. 85.5 Section 85.5 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION... PRODUCTS PSEUDORABIES § 85.5 Interstate movement of infected swine or exposed swine. Infected swine...

  19. 49 CFR 195.569 - Do I have to examine exposed portions of buried pipelines?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.569 Do I have to examine... exposed, you must examine the exposed portion for evidence of external corrosion if the pipe is bare, or if the coating is deteriorated. If you find external corrosion requiring corrective action...

  20. 49 CFR 195.569 - Do I have to examine exposed portions of buried pipelines?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.569 Do I have to examine... exposed, you must examine the exposed portion for evidence of external corrosion if the pipe is bare, or if the coating is deteriorated. If you find external corrosion requiring corrective action...

  1. [Peculiarities of nervous system functional state in electric welders exposed to manganese compounds].

    PubMed

    Chashchin, M V; Ellingsen, D G; Zibarev, E V; Kusraeva, Z S; Konstantinov, R V; Kuz'min, A V; Thomassen, Y

    2009-01-01

    Peculiarities of nervous system functional state in electric welders exposed to manganese compounds. To evaluate nervous system functional state in electric welders exposed to manganese compounds, the authors conducted transverse study with matched pairs. The electric welders' tests for response rate, diadochokinesis and grasping power were not reliable. No changes were found in tremor characteristics and posture steadiness. Bradykinesia appeared to prevail in welders.

  2. Resilience among Children Exposed to Domestic Violence: The Role of Risk and Protective Factors

    ERIC Educational Resources Information Center

    Martinez-Torteya, Cecilia; Bogat, G. Anne; von Eye, Alexander; Levendosky, Alytia A.

    2009-01-01

    Individual and family characteristics that predict resilience among children exposed to domestic violence (DV) were examined. Mother-child dyads (n = 190) were assessed when the children were 2, 3, and 4 years of age. DV-exposed children were 3.7 times more likely than nonexposed children to develop internalizing or externalizing problems.…

  3. 46 CFR 169.721 - Storm sails and halyards (exposed and partially protected waters only).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Storm sails and halyards (exposed and partially... § 169.721 Storm sails and halyards (exposed and partially protected waters only). (a) Unless clearly unsuitable, each vessel must have one storm trysail of appropriate size. It must be sheeted independently...

  4. 46 CFR 169.721 - Storm sails and halyards (exposed and partially protected waters only).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Storm sails and halyards (exposed and partially... § 169.721 Storm sails and halyards (exposed and partially protected waters only). (a) Unless clearly unsuitable, each vessel must have one storm trysail of appropriate size. It must be sheeted independently...

  5. 46 CFR 169.721 - Storm sails and halyards (exposed and partially protected waters only).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Storm sails and halyards (exposed and partially... § 169.721 Storm sails and halyards (exposed and partially protected waters only). (a) Unless clearly unsuitable, each vessel must have one storm trysail of appropriate size. It must be sheeted independently...

  6. 46 CFR 169.721 - Storm sails and halyards (exposed and partially protected waters only).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Storm sails and halyards (exposed and partially... § 169.721 Storm sails and halyards (exposed and partially protected waters only). (a) Unless clearly unsuitable, each vessel must have one storm trysail of appropriate size. It must be sheeted independently...

  7. 46 CFR 169.721 - Storm sails and halyards (exposed and partially protected waters only).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Storm sails and halyards (exposed and partially... § 169.721 Storm sails and halyards (exposed and partially protected waters only). (a) Unless clearly unsuitable, each vessel must have one storm trysail of appropriate size. It must be sheeted independently...

  8. Induction of adaptive response in mice exposed to 900MHz radiofrequency fields: application of micronucleus assay.

    PubMed

    Jiang, Bingcheng; Zong, Chunyan; Zhao, Hua; Ji, Yongxin; Tong, Jian; Cao, Yi

    2013-03-18

    Adult male ICR mice were pre-exposed to non-ionizing radiofrequency fields (RF), 900MHz at 120μW/cm(2) power density for 4h/day for 7 days (adaptation dose, AD) and then subjected to an acute whole body dose of 3Gy γ-radiation (challenge dose, CD). The classical micronucleus (MN) assay was used to determine the extent of genotoxicity in immature erythrocytes in peripheral blood and bone marrow. The data obtained in mice exposed to AD+CD were compared with those exposed to CD alone. The results indicated that in both tissues, the MN indices were similar in un-exposed controls and those exposed to AD alone while a significantly increased MN frequency was observed in mice exposed to CD alone. Exposure of mice to AD+CD resulted in a significant decrease in MN indices compared to those exposed to CD alone. Thus, the data suggested that pre-exposure of mice to non-ionizing RF is capable of 'protecting' the erythrocytes in the blood and bone marrow from genotoxic effects of subsequent γ-radiation. Such protective phenomenon is generally described as 'adaptive response' (AR) and is well documented in human and animal cells which were pre-exposed to very low doses of ionizing radiation. It is interesting to observe AR being induced by non-ionizing RF.

  9. An Exploratory Study of Drug-Exposed Infants: Case Substantiation and Subsequent Child Maltreatment

    ERIC Educational Resources Information Center

    Sun, An-Pyng; Freese, Margaret P.; Fitzgerald, Mark

    2007-01-01

    This study explores factors related to drug-exposed infants' case substantiation and subsequent child maltreatment. Child protective services computerized administrative data (from January 1998 to October 2001) were obtained from an urban Nevada county. The data included 457 drug-exposed infant cases. Chi-square, t-test, one-way ANOVA, and…

  10. Modeling lung cancer risks in laboratory dogs exposed to inhaled plutonium

    SciTech Connect

    Gilbert, E.S.; Park, J.F.; Buschbom, R.L.

    1990-06-01

    These analyses are based on data from a lifespan study of beagle dogs exposed to inhaled plutonium being conducted at Pacific Northwest Laboratory. An important goal of this study is to increase understanding of health risk resulting from this exposure, with particular attention to lung cancer risks. Data on humans exposed to plutonium are inadequate for achieving this goal.

  11. Response inhibition among early adolescents prenatally exposed to tobacco: An fMRI study

    PubMed Central

    Bennett, David S.; Mohamed, Feroze B.; Carmody, Dennis P.; Bendersky, Margaret; Patel, Sunil; Khorrami, Maryam; Faro, Scott H.; Lewis, Michael

    2009-01-01

    Children prenatally exposed to tobacco have been found to exhibit increased rates of behavior problems related to response inhibition deficits. The present study compared the brain function of tobacco-exposed (n = 7) and unexposed (n = 11) 12-year-olds during a Go/No-Go response inhibition task using an event-related functional MRI (fMRI) design. Prenatal alcohol exposure, neonatal medical problems, environmental risk, IQ, current environmental smoke exposure, and handedness were statistically controlled. Tobacco-exposed children showed greater activation in a relatively large and diverse set of regions, including left frontal, right occipital, and bilateral temporal, and parietal regions. In contrast, unexposed but not exposed children showed activation in the cerebellum, which prior research has indicated is important for attention and motor preparation. The diversity of regions showing greater activation among tobacco-exposed children suggests that their brain function is characterized by an inefficient recruitment of regions required for response inhibition. PMID:19351556

  12. Respiratory symptoms and lung function in oil mist-exposed workers

    SciTech Connect

    Jarvholm, B.; Bake, B.; Lavenius, B.; Thiringer, G.; Vokmann, R.

    1982-06-01

    The prevalence of respiratory symptoms was registered and ventilatory function was determined in 164 men exposed to oil mist. The average exposure time was 16.2 years. One hundred fifty-nine office workers served as controls. The exposed men reported more respiratory symptoms: 14% of the exposed nonsmokers v. 2% of the nonsmoking controls having cough at least three months a year. There were non significant differences between spirometric measurements and chest roentgenograms of the men exposed to oil mist and those of the office workers. The lung function of 25 nonsmoking exposed men was further examined with other lung function tests. The mean values for closing volume, slope of the alveolar plateau, total lung capacity, residual volume, elastic recoil at various lung volumes, and diffusion capacity did not differ significantly.

  13. Theoretical study of liquid-immersed exposed-core microstructured optical fibers for sensing.

    PubMed

    Warren-Smith, S C; Afshar, S; Monro, T M

    2008-06-09

    The absorption and fluorescence sensing properties of liquid-immersed exposed-core microstructured optical fibers are explored for the regime where these structures act as supported nanowires with direct access to the sensing environment. For absorption-based sensing we demonstrate that the amount of power propagating in the sensing region of the exposed-core fiber can compete with that of traditional MOFs. For fluorescence-based sensing, we see that in addition to the enhanced fluorescence capture efficiency already predicted for small-core, high refractive index contrast fibers, an improvement of up to 29% can be gained by using liquid-immersed exposed-core fibers. Additionally, calculation of the losses associated with interfaces between filled and unfilled sections predict significant benefit in using high refractive index substrate glasses for liquid-immersed exposed-core fiber sensing. This work demonstrates that, for fiber dimensions of interest, the exposed-core fiber is an attractive new sensor technology.

  14. Bone lead content assessed by L-line x-ray fluorescence in lead-exposed and non-lead-exposed suburban populations in the United States.

    PubMed Central

    Rosen, J F; Crocetti, A F; Balbi, K; Balbi, J; Bailey, C; Clemente, I; Redkey, N; Grainger, S

    1993-01-01

    Measurements of lead (Pb) in bone reflect cumulative Pb exposure, whereas blood Pb levels are indices of absorption during the previous 21-30 days. This study was undertaken to estimate bone Pb concentrations by L-line x-ray fluorescence (LXRF) in a United States suburban population which was exposed to unusually high levels of Pb in emissions from an adjacent factory during 1963-1981, compared with concentrations similarly estimated in a matched suburban community without unusual Pb exposure. The mean bone Pb value in 269 residents of the highly exposed suburb (15 ppm) was 3-fold greater than that of the reference suburb (5 ppm). LXRF estimates of bone Pb identified those individuals at risk for adverse effects of Pb, whereas blood Pb levels were uninformative. Average LXRF-estimated bone Pb concentrations in residents of the unusually exposed suburb approximated estimated values in workers at Pb-processing factories. Images Fig. 1 PMID:8464891

  15. Bone lead content assessed by L-line x-ray fluorescence in lead-exposed and non-lead-exposed suburban populations in the United States

    SciTech Connect

    Rosen, J.F.; Balbi, K.; Balbi, J.; Bailey, C.; Clemente, I.; Redkey, N.; Grainger, S. ); Crocetti, A.F. )

    1993-04-01

    Measurements of lead (Pb) in bone reflect cumulative Pb exposure, whereas blood Pb levels are indices of absorption during the previous 21-30 days. This study was undertaken to estimate bone Pb concentrations by L-line x-ray fluorescence (LXRF) in a United States suburban population which was exposed to unusually high levels of Pb in emissions from an adjacent factory during 1963-1981, compared with concentrations similarly estimated in a matched suburban community without unusual Pb exposure. The mean bone Pb value in 269 residents of the highly exposed suburb (15 ppm) was 3-fold greater than that of the reference suburb (5 ppm). LXRF estimates of bone Pb identified those individuals at risk for adverse effects of Pb, whereas blood Pb levels were uninformative. Average LXRF-estimated bone Pb concentrations in residents of the unusually exposed suburb approximated estimated values in workers at Pb-processing factories. 44 refs., 1 fig., 1 tab.

  16. Cytogenetic biomonitoring in a Mexican floriculture worker group exposed to pesticides.

    PubMed

    Gómez-Arroyo, S; Díaz-Sánchez, Y; Meneses-Pérez, M A; Villalobos-Pietrini, R; De León-Rodríguez, J

    2000-03-03

    The cytogenetic damage in floriculturists of Morelos State, Mexico, exposed to pesticides, was evaluated by mean of biological tests based on sister chromatid exchanges (SCE) in lymphocytes of peripheral blood and micronuclei (MN) in exfoliated cells of the buccal mucosa. Besides the cytogenetic analysis, the effects of pesticides exposure on the cell proliferation kinetics (CPK) by the replication index (RI) were also studied. The mitotic index (MI) to detect cytotoxic effects was also determined. Greenhouses of the towns of Santa Catarina, Jiutepec and Yecapixtla were selected for the study, because the application of chemicals to the flowers is uncontrolled. As non-exposed group, people of the town of Temisco were chosen; their activity was not related to pesticides. The SCE were analyzed in the peripheral blood of 30 persons, 22 women and 8 men, with 10 and 1.5 years of exposure to pesticides, respectively, and of 30 persons, 28 women and 2 men, that were considered as the non-exposed group. Samples of buccal mucosa were also taken from each person. Significant differences between exposed and non-exposed groups were found in SCE, CKP and MI. Besides, the MN frequencies in the exposed group were three times higher than in the non-exposed group.

  17. Dysregulation of cardiac autonomic function in offspring exposed to alcohol during antenatal period.

    PubMed

    Chandran, Sajish; Abhishekh, Hulegar A; Murthy, Pratima; Raju, Trichur R; Sathyaprabha, Talakad N

    2015-10-01

    Several lines of investigations have shown the deleterious effect of an alcohol on the autonomic nervous system. Recent evidence shows that infants exposed to alcohol during the antenatal period displayed aberration in the cardiac autonomic function after the birth. However, there is dearth of literature on the long term influence of antenatal alcohol exposure. In this study we measured the cardiac autonomic functions in children who were exposed to alcohol in the antenatal period and compared them with non-exposed control children. Twenty eight children (age: 9±2 years) in the antenatal alcohol exposed group and age, gender matched 30 non exposed healthy volunteers as a control (age: 10±2 years) were recruited. Electrocardiogram was recorded in all subjects at rest in the supine position. HRV parameters were analyzed in the time and frequency domains using customized software. The average heart rate was similar between both the groups. There was no statistical significant difference in the time domain measures between the groups. However, the low frequency power, normalized units and low frequency to high frequency ratio were significantly higher in the antenatal alcohol exposed children compared to the controls. This suggests sympathetic predominance in children who were exposed to alcohol in the antenatal period. In this study we provide evidence for the deleterious long lasting effect of antenatal exposure of alcohol on cardiac autonomic regulation. Further prospective studies are needed to confirm the causal relationship between antenatal alcohol exposure and autonomic dysregulation.

  18. Dominant lethal mutation test in male mice exposed to 900MHz radiofrequency fields.

    PubMed

    Zhu, Shunxing; Zhang, Jie; Liu, Chun; He, Qina; Vijayalaxmi; Prihoda, Thomas J; Tong, Jian; Cao, Yi

    2015-10-01

    Adult male ICR mice were exposed to continuous wave 900MHz radiofrequency fields (RF) at 1.6mW/cm(2) power intensity (whole body average specific absorption rate of 0.731W/kg) for 4 hour/day for 15 days. At the end of exposure, each mouse was caged with 3 mature virgin female mice for mating. After 7 days, each male mouse was transferred to a fresh cage and mated with a second batch of 3 females. This process was repeated for a total of 4 consecutive weeks. Sham exposed male mice and those subjected to an acute 2Gy γ-irradiation (GR) were handled similarly and used as un-exposed and positive controls, respectively. All females were sacrificed on the 18th day of gestation and presumptive mating and, the contents in their uteri were examined. The overall observations during the 4 weeks of mating indicated that the un-exposed female mice mated to RF-exposed male mice showed no significant differences in the percentage of pregnancies, total implants, live implants and dead implants when compared with those mated with sham-exposed mice. In contrast, female mice mated with GR-exposed males showed a consistent pattern of significant differences in the above indices in each and all 4 weeks of mating. Thus, the data indicated an absence of mutagenic potential of RF exposure in the germ cells of male mice.

  19. Adaptive Response in Mice Exposed to 900 MHz Radiofrequency Fields: Primary DNA Damage

    PubMed Central

    Zhou, Zhen; Zhang, Jie; Tong, Jian; Cao, Yi

    2012-01-01

    The phenomenon of adaptive response (AR) in animal and human cells exposed to ionizing radiation is well documented in scientific literature. We have examined whether such AR could be induced in mice exposed to non-ionizing radiofrequency fields (RF) used for wireless communications. Mice were pre-exposed to 900 MHz RF at 120 µW/cm2 power density for 4 hours/day for 1, 3, 5, 7 and 14 days and then subjected to an acute dose of 3 Gy γ-radiation. The primary DNA damage in the form of alkali labile base damage and single strand breaks in the DNA of peripheral blood leukocytes was determined using the alkaline comet assay. The results indicated that the extent of damage in mice which were pre-exposed to RF for 1 day and then subjected to γ-radiation was similar and not significantly different from those exposed to γ-radiation alone. However, mice which were pre-exposed to RF for 3, 5, 7 and 14 days showed progressively decreased damage and was significantly different from those exposed to γ-radiation alone. Thus, the data indicated that RF pre-exposure is capable of inducing AR and suggested that the pre-exposure for more than 4 hours for 1 day is necessary to elicit such AR. PMID:22389679

  20. Analysis of emotionality and locomotion in radio-frequency electromagnetic radiation exposed rats.

    PubMed

    Narayanan, Sareesh Naduvil; Kumar, Raju Suresh; Paval, Jaijesh; Kedage, Vivekananda; Bhat, M Shankaranarayana; Nayak, Satheesha; Bhat, P Gopalakrishna

    2013-07-01

    In the current study the modulatory role of mobile phone radio-frequency electromagnetic radiation (RF-EMR) on emotionality and locomotion was evaluated in adolescent rats. Male albino Wistar rats (6-8 weeks old) were randomly assigned into the following groups having 12 animals in each group. Group I (Control): they remained in the home cage throughout the experimental period. Group II (Sham exposed): they were exposed to mobile phone in switch-off mode for 28 days, and Group III (RF-EMR exposed): they were exposed to RF-EMR (900 MHz) from an active GSM (Global system for mobile communications) mobile phone with a peak power density of 146.60 μW/cm(2) for 28 days. On 29th day, the animals were tested for emotionality and locomotion. Elevated plus maze (EPM) test revealed that, percentage of entries into the open arm, percentage of time spent on the open arm and distance travelled on the open arm were significantly reduced in the RF-EMR exposed rats. Rearing frequency and grooming frequency were also decreased in the RF-EMR exposed rats. Defecation boli count during the EPM test was more with the RF-EMR group. No statistically significant difference was found in total distance travelled, total arm entries, percentage of closed arm entries and parallelism index in the RF-EMR exposed rats compared to controls. Results indicate that mobile phone radiation could affect the emotionality of rats without affecting the general locomotion.

  1. Genetic and demographic responses of mosquitofish (Gambusia holbrooki) populations exposed to mercury for multiple generations

    SciTech Connect

    Tatara, C.P.; Mulvey, M.; Newman, M.C.

    1999-12-01

    Genetic and demographic responses of mosquitofish were examined after multiple generations of exposure to mercury. Previous studies of acute lethal exposures of mosquitofish to either mercury or arsenic demonstrated a consistent correlation between time to death and genotype at the glucosephosphate isomerase-2 (Gpi-2) locus. A mesocosm study involving mosquitofish populations exposed to mercury for 111 d showed significant female sexual selection and fecundity selection at the Gpi-2 locus. Here the mesocosm study was extended to populations exposed to mercury for several (approx. four) generations. After 2 years, control and mercury-exposed populations met Hardy-Weinberg expectations and showed no evidence of genetic bottlenecks. The mean number of heterozygous loci did not differ significantly between the mercury-exposed and control populations. Significant differences in allele frequencies at the Gpi-2 locus were observed between the mercury-exposed and control populations. Relative to the initial and control allele frequencies, the GPI-2{sup 100} allele frequency was lower, the Gpi-2{sup 66} allele frequency increased, but the Gpi-2{sup 38} allele frequency did not change in mercury-exposed populations. No significant differences were found in standard length, weight, sex ratio, or age class ratio between the control and mercury-exposed populations. Allele frequency changes at the Gpi-2 locus suggest population-level response to chronic mercury exposure. Changes in allele frequency may be useful as indicators of population response to contaminants, provided that the population in question is well understood.

  2. Blood level of cadmium and lead in occupationally exposed persons in Gwagwalada, Abuja, Nigeria

    PubMed Central

    2015-01-01

    This study was designed to assess the blood levels of cadmium and lead in some occupationally exposed individuals and compare the values with non-exposed individuals, with the aim of increasing the awareness of health risk caused by these heavy metals. A total of 120 subjects (64 occupationally exposed and 56 non-exposed subjects) with the age range of 15–40 years were studied in cross-sectional study conducted between September 2012 and February 2013 in Gwagwalada area of Abuja, Nigeria. Blood cadmium and lead were analyzed using an atomic absorption spectrophotometer (AAS). The respective mean blood levels of cadmium and lead were 11.63±1.73 μg/dl and 45.43±6.93 μg/dl in occupationally-exposed subjects, while in non-exposed subjects 2.03±0.55 μg/dl and 12.08±2.87 μg/dl. The results show that occupational exposure increases the blood level of cadmium and lead, which consequently increases the health risk of the exposed individuals. PMID:27486374

  3. Forced exercise improves passive avoidance memory in morphine-exposed rats.

    PubMed

    Saadipour, K; Sarkaki, A; Alaei, H; Badavi, M; Rahim, F

    2009-09-01

    The aim of this study was to investigate the effect of short-term forced exercise protocol on passive avoidance retention in morphine-exposed rats. Effects of morphine on acquisition and retrieval of retention have been proven in the avoidance paradigms. Twenty four male Wistar rats weighing 250-300 g were used in this study. Animals were randomly divided into four groups including: (1) non-morphine-exposed without exercise (nA.nE) (2) non-morphine-exposed with exercise (nA.E) (3) morphine-exposed without exercise (A.nE) and (4) morphine-exposed with exercise (A.E). Rats ran as forced exercise on the motorized treadmill 1 h daily for ten days. Morphine-exposed animals received intraperitoneal morphine during first 5 days of the exercise period and their dependence to morphine was confirmed by naloxane admistration (10 mg kg(-1), i.p.) and withdrawal test. After 10 days of forced exercise, step down latency was tested and Inflexion Ratio (IR) was evaluated in each rat. Baseline step down latencies before any morphine exposing or exercise have shown no significant alteration in all groups. Inflexion Ratio (IR) ofnA.E group has increased significantly (p<0.001) at 1, 3, 7 and 14 days after receiving shock (learning) compared to nA.nE and A.E groups. Our data showed that short-term forced exercise on treadmill improved retention in both morphine-exposed and non morphine-exposed rats at least up to 7 days and more than 14 days, respectively. Alteration in retention between exercised groups may attribute the release of adrenal stress hormones such as epinephrine and corticosterone because of the emotional arousal.

  4. Proliferation and cytogenetic studies in human blood lymphocytes exposed in vitro to 2450 MHz radiofrequency radiation.

    PubMed

    Vijayalaxmi; Mohan, N; Meltz, M L; Wittler, M A

    1997-12-01

    Aliquots of human peripheral blood collected from two healthy human volunteers were exposed in vitro to continuous wave 2450 MHz radiofrequency radiation (RFR), either continuously for a period of 90 min or intermittently for a total exposure period of 90 min (30 min on and 30 min off, repeated three times). Blood aliquots which were sham-exposed or exposed in vitro to 150 cGy gamma radiation served as controls. The continuous wave 2450 MHz RFR was generated with a net forward power of 34.5 W and transmitted from a standard gain rectangular antenna horn in a vertically downward direction. The mean power density at the position of the cells was 5.0 mW/cm2. The mean specific absorption rate calculated by Finite Difference Time Domain analysis was 12.46 W/kg. Immediately after exposure, lymphocytes were cultured for 48 and 72 h to determine the incidence of chromosomal aberrations and micronuclei, respectively. Proliferation indices were also recorded. There were no significant differences between RFR-exposed and sham-exposed lymphocytes with respect to; (a) mitotic indices; (b) incidence of cells showing chromosome damage; (c) exchange aberrations; (d) acentric fragments; (e) binucleate lymphocytes, and (f) micronuclei, for either the continuous or intermittent RFR exposures. In contrast, the response of positive control cells exposed to 150 cGy gamma radiation was significantly different from RFR-exposed and sham-exposed lymphocytes. Thus, there is no evidence for an effect on mitogen-stimulated proliferation kinetics or for excess genotoxicity within 72 h in human blood lymphocytes exposed in vitro to 2450 MHz RFR.

  5. An update of corrosion inhibitors for mild steel exposed to 32-0-0 UAN solution

    SciTech Connect

    Nguyen, D.T.; Nichols, D.E.; Lohry, E.J.

    1994-10-01

    This is a continuation of corrosion studies on the effectiveness of commercial and newly-developed corrosion inhibitors for use with mild steel exposed to urea-ammonium nitrate (UAN) solution. This paper provides updated information on five newly-developed corrosion inhibitors. Tests were conducted with mild steel exposed to 32-0-0 UAN solution containing each corrosion inhibitor at ambient temperature and under static conditions. Real-time corrosion of the test specimens was monitored using AC impedance techniques. Corrosion performance of the inhibitors was evaluated based on comparison of the corrosion rate of specimens exposed to 32-0-0 UAN solution with and without a corrosion inhibitor.

  6. General guidelines for medically screening mixed population groups potentially exposed to nerve or vesicant agents

    SciTech Connect

    Watson, A.P.; Munro, N.B. ); Sidell, F.R. ); Leffingwell, S.S. . Center for Environmental Health and Injury Control)

    1992-01-01

    A number of state and local planners have requested guidance on screening protocols and have expressed interest in sampling body fluids from exposed or potentially exposed individuals as a means of estimating agent dose. These guidelines have been developed to provide a clear statement that could be used by state and local emergency response personnel in the event of a nerve or vesicant agent incident resulting in off-post contamination; maximum protection from harm is the goal. The assumption is that any population group so exposed would be heterogeneous for age, gender, reproductive status, and state of health.

  7. Transcriptomic responses of germinating Bacillus subtilis spores exposed to 1.5 years of space and simulated martian conditions on the EXPOSE-E experiment PROTECT.

    PubMed

    Nicholson, Wayne L; Moeller, Ralf; Horneck, Gerda

    2012-05-01

    Because of their ubiquity and resistance to spacecraft decontamination, bacterial spores are considered likely potential forward contaminants on robotic missions to Mars. Thus, it is important to understand their global responses to long-term exposure to space or martian environments. As part of the PROTECT experiment, spores of B. subtilis 168 were exposed to real space conditions and to simulated martian conditions for 559 days in low-Earth orbit mounted on the EXPOSE-E exposure platform outside the European Columbus module on the International Space Station. Upon return, spores were germinated, total RNA extracted, fluorescently labeled, and used to probe a custom Bacillus subtilis microarray to identify genes preferentially activated or repressed relative to ground control spores. Increased transcript levels were detected for a number of stress-related regulons responding to DNA damage (SOS response, SPβ prophage induction), protein damage (CtsR/Clp system), oxidative stress (PerR regulon), and cell envelope stress (SigV regulon). Spores exposed to space demonstrated a much broader and more severe stress response than spores exposed to simulated martian conditions. The results are discussed in the context of planetary protection for a hypothetical journey of potential forward contaminant spores from Earth to Mars and their subsequent residence on Mars.

  8. The AMINO experiment: exposure of amino acids in the EXPOSE-R experiment on the International Space Station and in laboratory

    NASA Astrophysics Data System (ADS)

    Bertrand, Marylène; Chabin, Annie; Colas, Cyril; Cadène, Martine; Chaput, Didier; Brack, Andre; Cottin, Herve

    2015-01-01

    In order to confirm the results of previous experiments concerning the chemical behaviour of organic molecules in the space environment, organic molecules (amino acids and a dipeptide) in pure form and embedded in meteorite powder were exposed in the AMINO experiment in the EXPOSE-R facility onboard the International Space Station. After exposure to space conditions for 24 months (2843 h of irradiation), the samples were returned to the Earth and analysed in the laboratory for reactions caused by solar ultraviolet (UV) and other electromagnetic radiation. Laboratory UV exposure was carried out in parallel in the Cologne DLR Center (Deutsches Zentrum für Luft und Raumfahrt). The molecules were extracted from the sample holder and then (1) derivatized by silylation and analysed by gas chromatography coupled to a mass spectrometer (GC-MS) in order to quantify the rate of degradation of the compounds and (2) analysed by high-resolution mass spectrometry (HRMS) in order to understand the chemical reactions that occurred. The GC-MS results confirm that resistance to irradiation is a function of the chemical nature of the exposed molecules and of the wavelengths of the UV light. They also confirm the protective effect of a coating of meteorite powder. The most altered compounds were the dipeptides and aspartic acid while the most robust were compounds with a hydrocarbon chain. The MS analyses document the products of reactions, such as decarboxylation and decarbonylation of aspartic acid, taking place after UV exposure. Given the universality of chemistry in space, our results have a broader implication for the fate of organic molecules that seeded the planets as soon as they became habitable as well as for the effects of UV radiation on exposed molecules at the surface of Mars, for example.

  9. Evolution of organic molecules under Mars-like UV radiation with EXPOSE-R2, a photochemistry experiment outside the International Space Station

    NASA Astrophysics Data System (ADS)

    Rouquette, Laura; Stalport, Fabien; Cottin, Hervé; Coll, Patrice; Szopa, Cyril; Saiagh, Kafila; Poch, Olivier; Khalaf, Diana; Chaput, Didier; Grira, Katia; Chaouche, Naila; Dequaire, Tristan

    2016-10-01

    The detection and identification of organic molecules on Mars are of prime importance, as some of these molecules are life precursors and components. While in situ planetary missions are searching for them, it is essential to understand how organic molecules evolve and are preserved at the surface of Mars. Indeed the harsh conditions of the environment of Mars such as ultraviolet (UV) radiation or oxidative processes could explain the low abundance and diversity of organic molecules detected by now.The EXPOSE R2 facility has been placed in low Earth orbit (LEO) under solar radiation, outside the International Space Station (ISS) in 2014. One of the EXPOSE R2 experiment, called PSS (Photochemistry on the Space Station), is dedicated to astrobiology- and astrochemistry-related studies. Part of PSS samples have been dedicated to the study of the evolution of organic molecules under Mars-like surface radiation conditions. Indeed, UV radiation above 200 nm reaches the surface of Mars and could degrade organic matter. Organic samples have been exposed directly to the Sun under KBr filters (>200 nm) from November 2014 to February 2016, mimicking the UV radiation conditions of the surface of Mars. Four types of samples were exposed as thin layers of solid molecules: adenine, adenine with nontronite (a kind of clay mineral detected on Mars), chrysene and glycine with nontronite.To characterize the evolution of our samples under irradiation, infrared (IR) transmission analyses were performed, before the launch of EXPOSE R2 to the ISS in 2014, and after the exposure in space and the return on Earth, this year. These analyses allowed determining whether each molecule is preserved or photodegraded, and if so, its photolysis rate. The effect of nontronite on organic molecules preservation has been investigated as well. We also compared these results from LEO with laboratory data, obtained by irradiating organic samples under a UV lamp.

  10. USING PROTEOMICS TO MONITOR PROTEIN EXPRESSION IN HUMAN CELLS EXPOSED TO CARCINOGENS

    EPA Science Inventory

    People are continuously exposed exogenously to varying amounts of chemicals that have been shown to have carcinogenic properties in experimental systems. It has been estimated that exposure to environmental chemical carcinogens in the environment may contribute significantly to t...

  11. 20. Top 30/3. Plan of exposed substructure elevations. Wyoming ...

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

    20. Top 30/3. Plan of exposed substructure elevations. - Wyoming Valley Flood Control System, Woodward Pumping Station, East of Toby Creek crossing by Erie-Lackawanna Railroad, Edwardsville, Luzerne County, PA

  12. An Atypical Withdrawal Syndrome in Neonates Prenatally Exposed to Gabapentin and Opioids.

    PubMed

    Loudin, Sean; Murray, Sara; Prunty, Leesa; Davies, Todd; Evans, Joseph; Werthammer, Joseph

    2017-02-01

    We report a retrospective case series of 19 infants exposed to both opioids and gabapentin prenatally. We describe a unique behavioral phenotype in 15 of these infants and report a treatment strategy.

  13. 1 in 4 Teens Exposed to Secondhand E-Cig Vapors: Report

    MedlinePlus

    ... also much more likely to be around e-cigarettes To use the sharing features on this page, ... ve been exposed to potentially dangerous secondhand e-cigarette vapors, a federal government study shows. E-cigarette ...

  14. COMPARISON OF BIOMARKERS IN WORKERS EXPOSED TO 2,4,6-TRINITROTOLUENE

    EPA Science Inventory

    2,4,6-Trinitrotoluene (TNT) is an important occupational and environmental pollutant. In TNT-exposed humans, the notable toxic manifestations have included aplastic anemia, toxic hepatitis, cataracts, hepatomegaly, and liver cancer. Therefore, we developed methods to biomonitor w...

  15. OOCYTE ENVELOPE PROTEINS AND VITELLOGENIN IN MALE SHEEPHEAD MINNOW EXPOSED TO ESTRADIOL

    EPA Science Inventory

    Oocyte Envelope Proteins and Vitellogenin Expression in Male Sheepshead Minnows Exposed to Estradiol (Abstract). To be presented at the 22nd Annual Meeting of the Society of Environmental Toxicology and Chemistry: Changing Environmental Awareness: Societal Concerns and Scientifi...

  16. ANTIOXIDANT SUPPLEMENTATION AND NASAL INFLAMMATORY RESPONSES AMONG YOUNG ASTHMATICS EXPOSED TO HIGH LEVELS OF OZONE

    EPA Science Inventory

    Background: Recent studies examining the inflammatory response in atopic asthma to ozone suggest a release of soluble mediators of inflammation factors that might be related to reactive oxygen species (ROS). Antioxidant could prove useful in subjects exposed to additional oxidati...

  17. Gene Expression Responses in Male Fathead Minnows Exposed to Binary Mixtures of an Estrogen and Antiestrogen

    EPA Science Inventory

    Aquatic organisms are continuously exposed to complex mixtures of chemicals, many of which can interfere with their endocrine system, resulting in impaired reproduction, development or survival, among others. In order to analyze the effects and mechanisms of action of estrogen...

  18. Exploring a partially enclosed space by lead-exposed female rhesus monkeys.

    PubMed

    Lasky, R E; Laughlin, N K

    2001-01-01

    Beginning on Day 8 postpartum, lead acetate was administered to female rhesus monkeys (n=48). Their blood lead levels rose to 35-40 microg/dl (the level maintained for the duration of the study period) by 12 weeks of age. Weekly, these lead-exposed monkeys and their controls (n=23) were placed in a partially enclosed space from the second postnatal week until they escaped three times or were 26 weeks old. The lead-exposed monkeys exhibited more fear, were more likely to be agitated, and climbed more frequently during the first testing session. In subsequent sessions, they more frequently explored the periphery of the test area than the controls. The lead-exposed monkeys also tended to escape sooner although that trend did not consistently reach the.05 level of significance. The increased activity and agitation of the lead-exposed monkeys is suggestive of deficits reported in human children with high blood lead levels.

  19. Autosomal mutants of proton-exposed kidney cells display frequent loss of heterozygosity on nonselected chromosomes.

    PubMed

    Grygoryev, Dmytro; Dan, Cristian; Gauny, Stacey; Eckelmann, Bradley; Ohlrich, Anna P; Connolly, Marissa; Lasarev, Michael; Grossi, Gianfranco; Kronenberg, Amy; Turker, Mitchell S

    2014-05-01

    High-energy protons found in the space environment can induce mutations and cancer, which are inextricably linked. We hypothesized that some mutants isolated from proton-exposed kidneys arose through a genome-wide incident that causes loss of heterozygosity (LOH)-generating mutations on multiple chromosomes (termed here genomic LOH). To test this hypothesis, we examined 11 pairs of nonselected chromosomes for LOH events in mutant cells isolated from the kidneys of mice exposed to 4 or 5 Gy of 1 GeV protons. The mutant kidney cells were selected for loss of expression of the chromosome 8-encoded Aprt gene. Genomic LOH events were also assessed in Aprt mutants isolated from isogenic cultured kidney epithelial cells exposed to 5 Gy of protons in vitro. Control groups were spontaneous Aprt mutants and clones isolated without selection from the proton-exposed kidneys or cultures. The in vivo results showed significant increases in genomic LOH events in the Aprt mutants from proton-exposed kidneys when compared with spontaneous Aprt mutants and when compared with nonmutant (i.e., nonselected) clones from the proton-exposed kidneys. A bias for LOH events affecting chromosome 14 was observed in the proton-induced Aprt mutants, though LOH for this chromosome did not confer increased radiation resistance. Genomic LOH events were observed in Aprt mutants isolated from proton-exposed cultured kidney cells; however the incidence was fivefold lower than in Aprt mutants isolated from exposed intact kidneys, suggesting a more permissive environment in the intact organ and/or the evolution of kidney clones prior to their isolation from the tissue. We conclude that proton exposure creates a subset of viable cells with LOH events on multiple chromosomes, that these cells form and persist in vivo, and that they can be isolated from an intact tissue by selection for a mutation on a single chromosome.

  20. Prenatal substance abuse: short- and long-term effects on the exposed fetus.

    PubMed

    Behnke, Marylou; Smith, Vincent C

    2013-03-01

    Prenatal substance abuse continues to be a significant problem in this country and poses important health risks for the developing fetus. The primary care pediatrician's role in addressing prenatal substance exposure includes prevention, identification of exposure, recognition of medical issues for the exposed newborn infant, protection of the infant, and follow-up of the exposed infant. This report will provide information for the most common drugs involved in prenatal exposure: nicotine, alcohol, marijuana, opiates, cocaine, and methamphetamine.